Actually make use of ApplicationURLOpener

Progress on #4

README.md

@@ -1,4 +1,13 @@
 # nasin
 
-Nasin provides an easy way to write applications with Tomo. Parts of Tomo that
+[![Go Reference](https://pkg.go.dev/badge/git.tebibyte.media/tomo/nasin.svg)](https://pkg.go.dev/git.tebibyte.media/tomo/nasin)
-aren't the GUI toolkit may be found here.
+
+Nasin provides an easy way to write applications with Tomo. To get started, take
+a look at the [examples](examples) directory and the
+[online documentation](https://pkg.go.dev/git.tebibyte.media/tomo/nasin).
+
+Related repositories:
+- [Tomo API](https://git.tebibyte.media/tomo/tomo): The API that all other parts
+  of the toolkit agree on
+- [Objects](https://git.tebibyte.media/tomo/objects): A standard collection of
+  re-usable objects and other GUI components

application.go

@@ -1,7 +1,15 @@
 package nasin
 
+import "fmt"
+import "log"
+import "flag"
 import "image"
+import "strings"
+import "net/url"
 import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/objects"
+import "git.tebibyte.media/tomo/tomo/canvas"
+import "git.tebibyte.media/tomo/nasin/internal/registrar"
 
 // Application represents an application object.
 type Application interface {
@@ -9,7 +17,36 @@ type Application interface {
 	Describe () ApplicationDescription
 
 	// Init performs the initial setup of the application.
-	Init ()
+	Init () error
+}
+
+// ApplicationURLOpener is an application that can open a URL.
+type ApplicationURLOpener interface {
+	Application
+
+	// OpenURL opens a new window with the contents of the given URL. If the
+	// given URL is unsupported, it returns an error (for example, an image
+	// viewer is not expected to open a text file).
+	//
+	// Applications should support the file:// scheme at the very least, and
+	// should also support others like http:// and https:// if possible.
+	OpenURL (*url.URL) error
+
+	// OpenNone is called when the application is launched without any URLs
+	// to open. The application may create some sort of default starting
+	// window, or call tomo.Stop().
+	OpenNone ()
+}
+
+// ApplicationFlagAdder is an application that supports reading command line
+// flags.
+type ApplicationFlagAdder interface {
+	Application
+
+	// AddFlags is called before Init and given the default flag set that
+	// Nasin uses to parse command line arguments. Note that when this
+	// method is called, Tomo will not yet be initialized.
+	AddFlags (*flag.FlagSet)
 }
 
 // ApplicationDescription describes the name and type of an application.
@@ -74,17 +111,111 @@ type ApplicationRole string; const (
 	RoleChecklist         ApplicationRole = "Checklist"
 )
 
-// RunApplication is like Run, but runs an application.
+// Icon returns the icon ID for this role.
-func RunApplication (application Application) error {
+func (role ApplicationRole) Icon () tomo.Icon {
-	return tomo.Run(application.Init)
+	if role == "" {
+		return tomo.IconApplication
+	} else {
+		return tomo.Icon("Application" + strings.ReplaceAll(string(role), " ", ""))
+	}
+}
+
+// RunApplication is like tomo.Run, but runs an application. If something fails
+// to initialize, an error is written to the standard logger.
+func RunApplication (application Application) {
+	// TODO: see #4
+
+	if application, ok := application.(ApplicationFlagAdder); ok {
+		application.AddFlags(flag.CommandLine)
+	}
+	flag.Parse()
+
+	err := registrar.RegisterBackend()
+	if err != nil { log.Fatalln("nasin: could not register backend:", err) }
+	err = tomo.Run(func () {
+		err := registrar.SetTheme()
+		if err != nil { log.Fatalln("nasin: could not set theme:", err) }
+		err = application.Init()
+		if err != nil { log.Fatalln("nasin: could not run application:", err) }
+
+		// open URLs
+		args := flag.Args()
+		applicationOpenUrls(application, args...)
+	})
+	if err != nil { log.Fatalln("nasin: could not run application:", err) }
 }
 
 // NewApplicationWindow creates a window for an application. It will
 // automatically set window information to signal to the OS that the window is
-// owned by the application.
+// owned by the application. The window's icon will be automatically set by
-func NewApplicationWindow (application Application, bounds image.Rectangle) (tomo.MainWindow, error) {
+// looking for an icon with the name of the application's ID. If that is not
+// found, the default icon for the application's ApplicationRole will used.
+func NewApplicationWindow (application Application, bounds image.Rectangle) (tomo.Window, error) {
 	window, err := tomo.NewWindow(bounds)
 	if err != nil { return nil, err }
-	window.SetTitle(application.Describe().String())
+	description := application.Describe()
+	window.SetTitle(description.Name)
+
+	setApplicationWindowIcon(window, description)
 	return window, nil
 }
+
+func applicationOpenUrls (application Application, args ...string) {
+	if application, ok := application.(ApplicationURLOpener); ok {
+		if len(args) <= 0 {
+			application.OpenNone()
+		}
+
+		openedAny := false
+		for _, arg := range flag.Args() {
+			ur, err := url.Parse(arg)
+			if err != nil {
+				log.Fatalf (
+					"nasin: invalid URL %v: %v",
+					arg, err)
+			}
+			if ur.Scheme == "" {
+				ur.Scheme = "file"
+			}
+			err = application.OpenURL(ur)
+			if err != nil {
+				dialog, err := objects.NewDialogOk (
+					objects.DialogError, nil,
+					"Could Not Open URL",
+					fmt.Sprintf (
+						"Could not open %v: %v",
+						arg, err),
+					func () {
+						if !openedAny {
+							application.OpenNone()
+						}
+					})
+				if err != nil { log.Fatal(err) }
+				dialog.SetVisible(true)
+			}
+		}
+	} else {
+		log.Fatal("nasin: this application cannot open URLs")
+	}
+}
+
+func setApplicationWindowIcon (window tomo.Window, description ApplicationDescription) {
+	allSizes := func (icon tomo.Icon) (sizes []canvas.Texture) {
+		small  := icon.Texture(tomo.IconSizeSmall)
+		medium := icon.Texture(tomo.IconSizeMedium)
+		large  := icon.Texture(tomo.IconSizeLarge)
+		if small  != nil { sizes = append(sizes,  small) }
+		if medium != nil { sizes = append(sizes, medium) }
+		if large  != nil { sizes = append(sizes,  large) }
+		return sizes
+	}
+
+	if sizes := allSizes(tomo.Icon(description.ID)); len(sizes) > 0 {
+		window.SetIcon(sizes...)
+		return
+	}
+	if sizes := allSizes(description.Role.Icon()); len(sizes) > 0 {
+		window.SetIcon(sizes...)
+		return
+	}
+}

backend.go

@@ -1,8 +0,0 @@
-package nasin
-
-import "git.tebibyte.media/tomo/x"
-import "git.tebibyte.media/tomo/tomo"
-
-func init () {
-	tomo.Register(1, x.NewBackend)
-}

go.mod

@@ -3,17 +3,18 @@ module git.tebibyte.media/tomo/nasin
 go 1.20
 
 require (
-	git.tebibyte.media/tomo/tomo v0.30.0
+	git.tebibyte.media/tomo/backend v0.4.1
-	git.tebibyte.media/tomo/x v0.6.0
+	git.tebibyte.media/tomo/objects v0.19.0
+	git.tebibyte.media/tomo/tomo v0.38.0
 	git.tebibyte.media/tomo/xdg v0.1.0
+	golang.org/x/image v0.11.0
 )
 
 require (
-	git.tebibyte.media/tomo/typeset v0.7.0 // indirect
+	git.tebibyte.media/tomo/typeset v0.7.1 // indirect
 	git.tebibyte.media/tomo/xgbkb v1.0.1 // indirect
 	github.com/BurntSushi/freetype-go v0.0.0-20160129220410-b763ddbfe298 // indirect
 	github.com/BurntSushi/graphics-go v0.0.0-20160129215708-b43f31a4a966 // indirect
-	github.com/jezek/xgb v1.1.0 // indirect
+	github.com/jezek/xgb v1.1.1 // indirect
-	github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0 // indirect
+	github.com/jezek/xgbutil v0.0.0-20231116234834-47f30c120111 // indirect
-	golang.org/x/image v0.11.0 // indirect
 )

go.sum

@@ -1,10 +1,12 @@
 git.tebibyte.media/sashakoshka/xgbkb v1.0.0/go.mod h1:pNcE6TRO93vHd6q42SdwLSTTj25L0Yzggz7yLe0JV6Q=
-git.tebibyte.media/tomo/tomo v0.30.0 h1:JoTklJ7yFVrzre4AwuKBMwzho9GomC9ySw354wDB4f4=
+git.tebibyte.media/tomo/backend v0.4.1 h1:rpkyTAfp/PE56aSqKNxtSN+D/aBSW8wjJ/vTtSgqQhE=
-git.tebibyte.media/tomo/tomo v0.30.0/go.mod h1:C9EzepS9wjkTJjnZaPBh22YvVPyA4hbBAJVU20Rdmps=
+git.tebibyte.media/tomo/backend v0.4.1/go.mod h1:2G04zmKbzf5fA/xzsjoQRrN55BWZkB+vknFxd3ialZ0=
-git.tebibyte.media/tomo/typeset v0.7.0 h1:JFpEuGmN6R2XSCvkINYxpH0AyYUqqs+dZYr6OSd91y0=
+git.tebibyte.media/tomo/objects v0.19.0 h1:ibnAoPvkPTiuJGlqQDnoGVZBQiUT/GZo1qqvDDUCK4w=
-git.tebibyte.media/tomo/typeset v0.7.0/go.mod h1:PwDpSdBF3l/EzoIsa2ME7QffVVajnTHZN6l3MHEGe1g=
+git.tebibyte.media/tomo/objects v0.19.0/go.mod h1:GP5BZ6lc2F2D0OxERfr9r46PIk7jFlpq2/BWOpoQDqc=
-git.tebibyte.media/tomo/x v0.6.0 h1:80BRiSwhZCqu6IPKZoQj7t1puKXXJpMB9eWVHQliTHM=
+git.tebibyte.media/tomo/tomo v0.38.0 h1:K5TP67RxnszudeNfmGZiU5cFTRjFueXiI3NCsgw+05U=
-git.tebibyte.media/tomo/x v0.6.0/go.mod h1:6INfDGlcPyoYVMem64ScD5AZb43PkXDGkfgaNa5GCqQ=
+git.tebibyte.media/tomo/tomo v0.38.0/go.mod h1:C9EzepS9wjkTJjnZaPBh22YvVPyA4hbBAJVU20Rdmps=
+git.tebibyte.media/tomo/typeset v0.7.1 h1:aZrsHwCG5ZB4f5CruRFsxLv5ezJUCFUFsQJJso2sXQ8=
+git.tebibyte.media/tomo/typeset v0.7.1/go.mod h1:PwDpSdBF3l/EzoIsa2ME7QffVVajnTHZN6l3MHEGe1g=
 git.tebibyte.media/tomo/xdg v0.1.0 h1:6G2WYPPiM2IXleCpKKHuJA34BxumwNWuLsUoX3yu5zA=
 git.tebibyte.media/tomo/xdg v0.1.0/go.mod h1:tuaRwRkyYW7mqlxA7P2+V+e10KzcamNoUzcOgaIYKAY=
 git.tebibyte.media/tomo/xgbkb v1.0.1 h1:b3HDUopjdQp1MZrb5Vpil4bOtk3NnNXtfQW27Blw2kE=
@@ -13,10 +15,12 @@ github.com/BurntSushi/freetype-go v0.0.0-20160129220410-b763ddbfe298 h1:1qlsVAQJ
 github.com/BurntSushi/freetype-go v0.0.0-20160129220410-b763ddbfe298/go.mod h1:D+QujdIlUNfa0igpNMk6UIvlb6C252URs4yupRUV4lQ=
 github.com/BurntSushi/graphics-go v0.0.0-20160129215708-b43f31a4a966 h1:lTG4HQym5oPKjL7nGs+csTgiDna685ZXjxijkne828g=
 github.com/BurntSushi/graphics-go v0.0.0-20160129215708-b43f31a4a966/go.mod h1:Mid70uvE93zn9wgF92A/r5ixgnvX8Lh68fxp9KQBaI0=
-github.com/jezek/xgb v1.1.0 h1:wnpxJzP1+rkbGclEkmwpVFQWpuE2PUGNUzP8SbfFobk=
 github.com/jezek/xgb v1.1.0/go.mod h1:nrhwO0FX/enq75I7Y7G8iN1ubpSGZEiA3v9e9GyRFlk=
-github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0 h1:Pf/0BAbppEOq4azPH6fnvUX2dycAwZdGkdxFn25j44c=
+github.com/jezek/xgb v1.1.1 h1:bE/r8ZZtSv7l9gk6nU0mYx51aXrvnyb44892TwSaqS4=
+github.com/jezek/xgb v1.1.1/go.mod h1:nrhwO0FX/enq75I7Y7G8iN1ubpSGZEiA3v9e9GyRFlk=
 github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0/go.mod h1:AHecLyFNy6AN9f/+0AH/h1MI7X1+JL5bmCz4XlVZk7Y=
+github.com/jezek/xgbutil v0.0.0-20231116234834-47f30c120111 h1:cX/mTy4LgFtWqr5dCadtdJ4zdh/KtPco5yFLsliaFyU=
+github.com/jezek/xgbutil v0.0.0-20231116234834-47f30c120111/go.mod h1:AHecLyFNy6AN9f/+0AH/h1MI7X1+JL5bmCz4XlVZk7Y=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=

internal/icons/fallback/icon.go

@@ -0,0 +1,455 @@
+package fallbackIcons
+
+import "bytes"
+import "image"
+import _ "embed"
+import _ "image/png"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/tomo/data"
+import "git.tebibyte.media/tomo/tomo/canvas"
+
+//go:embed assets/icons-small.png
+var atlasSmallBytes []byte
+//go:embed assets/icons-large.png
+var atlasLargeBytes []byte
+
+func generateSource (data []byte, width int) map[tomo.Icon] canvas.Texture {
+	atlasImage, _, err := image.Decode(bytes.NewReader(data))
+	if err != nil { panic(err) }
+	atlasTexture := tomo.NewTexture(atlasImage)
+
+	source := make(map[tomo.Icon] canvas.Texture)
+	x := 0
+	y := 0
+	
+	row := func () {
+		x = 0
+		y ++
+	}
+	col := func (id tomo.Icon) {
+		source[id] = atlasTexture.SubTexture(image.Rect (
+			x * width,
+			y * width,
+			(x + 1) * width,
+			(y + 1) * width))
+		x++
+	}
+
+	col(tomo.IconUnknown)
+	col(tomo.Icon("File"))
+
+	row()
+	// actions
+	col(tomo.IconAddressBookNew)
+	col(tomo.IconApplicationExit)
+	col(tomo.IconAppointmentNew)
+	col(tomo.IconCallStart)
+	col(tomo.IconCallStop)
+	col(tomo.IconContactNew)
+	// actions: dialog
+	col(tomo.IconDialogOkay)
+	col(tomo.IconDialogCancel)
+	// actions: edit
+	col(tomo.IconEditClear)
+	col(tomo.IconEditCopy)
+	col(tomo.IconEditCut)
+	col(tomo.IconEditDelete)
+	col(tomo.IconEditFind)
+	col(tomo.IconEditFindReplace)
+	col(tomo.IconEditPaste)
+	col(tomo.IconEditRedo)
+	col(tomo.IconEditSelectAll)
+	col(tomo.IconEditUndo)
+	// actions: file
+	col(tomo.IconFileNew)
+	col(tomo.IconDirectoryNew)
+	col(tomo.IconFileOpen)
+	col(tomo.IconFileOpenRecent)
+	col(tomo.IconFilePageSetup)
+	col(tomo.IconFilePrint)
+	col(tomo.IconFilePrintPreview)
+	col(tomo.IconFilePermissions)
+	col(tomo.IconFileProperties)
+	col(tomo.IconFileRename)
+	col(tomo.IconFileRevert)
+	col(tomo.IconFileSave)
+	col(tomo.IconFileSaveAs)
+	col(tomo.IconFileSend)
+
+	row()
+	// actions: format
+	col(tomo.IconFormatIndentLess)
+	col(tomo.IconFormatIndentMore)
+	col(tomo.IconFormatAlignCenter)
+	col(tomo.IconFormatAlignEven)
+	col(tomo.IconFormatAlignLeft)
+	col(tomo.IconFormatAlignRight)
+	col(tomo.IconFormatTextDirectionLtr)
+	col(tomo.IconFormatTextDirectionRtl)
+	col(tomo.IconFormatTextBold)
+	col(tomo.IconFormatTextItalic)
+	col(tomo.IconFormatTextUnderline)
+	col(tomo.IconFormatTextStrikethrough)
+	// actions: go
+	col(tomo.IconGoBottom)
+	col(tomo.IconGoDown)
+	col(tomo.IconGoFirst)
+	col(tomo.IconGoHome)
+	col(tomo.IconGoJump)
+	col(tomo.IconGoLast)
+	col(tomo.IconGoNext)
+	col(tomo.IconGoPrevious)
+	col(tomo.IconGoTop)
+	col(tomo.IconGoUp)
+	// actions: help
+	col(tomo.IconHelpAbout)
+	col(tomo.IconHelpContents)
+	col(tomo.IconHelpFaq)
+	// actions: insert
+	col(tomo.IconInsertImage)
+	col(tomo.IconInsertLink)
+	col(tomo.IconInsertObject)
+	col(tomo.IconInsertText)
+	// actions: list
+	col(tomo.IconListAdd)
+	col(tomo.IconListRemove)
+
+	row()
+	// actions: mail
+	col(tomo.IconMailForward)
+	col(tomo.IconMailMarkImportant)
+	col(tomo.IconMailMarkJunk)
+	col(tomo.IconMailMarkNotJunk)
+	col(tomo.IconMailMarkRead)
+	col(tomo.IconMailMarkUnread)
+	col(tomo.IconMailMessageNew)
+	col(tomo.IconMailReplyAll)
+	col(tomo.IconMailReplySender)
+	col(tomo.IconMailSend)
+	col(tomo.IconMailReceive)
+	// actions: media
+	col(tomo.IconMediaEject)
+	col(tomo.IconMediaPlaybackPause)
+	col(tomo.IconMediaPlaybackStart)
+	col(tomo.IconMediaPlaybackStop)
+	col(tomo.IconMediaRecord)
+	col(tomo.IconMediaSeekBackward)
+	col(tomo.IconMediaSeekForward)
+	col(tomo.IconMediaSkipBackward)
+	col(tomo.IconMediaSkipForward)
+	// actions: object
+	col(tomo.IconObjectFlipHorizontal)
+	col(tomo.IconObjectFlipVertical)
+	col(tomo.IconObjectRotateLeft)
+	col(tomo.IconObjectRotateRight)
+	// actions: process
+	col(tomo.IconProcessStop)
+	// actions: system
+	col(tomo.IconSystemLockScreen)
+	col(tomo.IconSystemLogOut)
+	col(tomo.IconSystemRun)
+	col(tomo.IconSystemSearch)
+	col(tomo.IconSystemReboot)
+	col(tomo.IconSystemShutdown)
+
+	row()
+	// actions: tools
+	col(tomo.IconToolsCheckSpelling)
+	// actions: value
+	col(tomo.IconValueIncrement)
+	col(tomo.IconValueDecrement)
+	col(tomo.IconValueReset)
+	// actions: view
+	col(tomo.IconViewFullscreen)
+	col(tomo.IconViewRefresh)
+	col(tomo.IconViewRestore)
+	col(tomo.IconViewSortAscending)
+	col(tomo.IconViewSortDescending)
+	// actions: window
+	col(tomo.IconWindowClose)
+	col(tomo.IconWindowNew)
+	// actions: zoom
+	col(tomo.IconZoomFitBest)
+	col(tomo.IconZoomIn)
+	col(tomo.IconZoomOriginal)
+	col(tomo.IconZoomOut)
+
+	row()
+	// applications
+	// Keep these in sync with nasin.ApplicationRole!
+	col(tomo.IconApplication)
+	col(tomo.IconApplicationWebBrowser)
+	col(tomo.IconApplicationMesssanger)
+	col(tomo.IconApplicationPhone)
+	col(tomo.IconApplicationMail)
+	col(tomo.IconApplicationTerminalEmulator)
+	col(tomo.IconApplicationFileBrowser)
+	col(tomo.IconApplicationTextEditor)
+	col(tomo.IconApplicationDocumentViewer)
+	col(tomo.IconApplicationWordProcessor)
+	col(tomo.IconApplicationSpreadsheet)
+	col(tomo.IconApplicationSlideshow)
+	col(tomo.IconApplicationCalculator)
+	col(tomo.IconApplicationPreferences)
+	col(tomo.IconApplicationProcessManager)
+	col(tomo.IconApplicationSystemInformation)
+	col(tomo.IconApplicationManual)
+	col(tomo.IconApplicationCamera)
+	col(tomo.IconApplicationImageViewer)
+	col(tomo.IconApplicationMediaPlayer)
+	col(tomo.IconApplicationImageEditor)
+	col(tomo.IconApplicationAudioEditor)
+	col(tomo.IconApplicationVideoEditor)
+	col(tomo.IconApplicationClock)
+	col(tomo.IconApplicationCalendar)
+	col(tomo.IconApplicationChecklist)
+
+	row()
+	// categories: applications
+	col(tomo.IconApplications)
+	col(tomo.IconApplicationsAccessories)
+	col(tomo.IconApplicationsDevelopment)
+	col(tomo.IconApplicationsEngineering)
+	col(tomo.IconApplicationsGames)
+	col(tomo.IconApplicationsGraphics)
+	col(tomo.IconApplicationsInternet)
+	col(tomo.IconApplicationsMultimedia)
+	col(tomo.IconApplicationsOffice)
+	col(tomo.IconApplicationsScience)
+	col(tomo.IconApplicationsSystem)
+	col(tomo.IconApplicationsUtilities)
+	// categories: preferences
+	col(tomo.IconPreferences)
+	col(tomo.IconPreferencesDesktop)
+	col(tomo.IconPreferencesPeripherals)
+	col(tomo.IconPreferencesPersonal)
+	col(tomo.IconPreferencesSystem)
+	col(tomo.IconPreferencesNetwork)
+
+	row()
+	// devices
+	col(tomo.IconDevice)
+	col(tomo.IconDeviceCamera)
+	col(tomo.IconDeviceWebCamera)
+	col(tomo.IconDeviceComputer)
+	col(tomo.IconDevicePda)
+	col(tomo.IconDevicePhone)
+	col(tomo.IconDevicePrinter)
+	col(tomo.IconDeviceScanner)
+	col(tomo.IconDeviceMultimediaPlayer)
+	col(tomo.IconDeviceVideoDisplay)
+	col(tomo.IconDeviceAudioInput)
+	col(tomo.IconDeviceAudioOutput)
+	// devices: hardware
+	col(tomo.IconHardware)
+	col(tomo.IconHardwareCPU)
+	col(tomo.IconHardwareGPU)
+	col(tomo.IconHardwareRAM)
+	col(tomo.IconHardwareSoundCard)
+	col(tomo.IconHardwareNetworkAdapter)
+	// devices: power
+	col(tomo.IconPowerBattery)
+	// devices: storage
+	col(tomo.IconStorageHardDisk)
+	col(tomo.IconStorageFloppyDisk)
+	col(tomo.IconStorageSolidState)
+	col(tomo.IconStorageOptical)
+	col(tomo.IconStorageFlashStick)
+	col(tomo.IconStorageFlashCard)
+	col(tomo.IconStorageMagneticTape)
+	// devices: input
+	col(tomo.IconInputGaming)
+	col(tomo.IconInputKeyboard)
+	col(tomo.IconInputMouse)
+	col(tomo.IconInputTablet)
+
+	row()
+	// devices: network
+	col(tomo.IconNetworkWired)
+	col(tomo.IconNetworkWireless)
+	col(tomo.IconNetworkCellular)
+	col(tomo.IconNetworkLocal)
+	col(tomo.IconNetworkInternet)
+	col(tomo.IconNetworkVPN)
+	col(tomo.IconNetworkServer)
+	col(tomo.IconNetworkWorkgroup)
+
+	row()
+	// emblems
+	col(tomo.IconEmblemDefault)
+	col(tomo.IconEmblemEncrypted)
+	col(tomo.IconEmblemFavorite)
+	col(tomo.IconEmblemImportant)
+	col(tomo.IconEmblemReadOnly)
+	col(tomo.IconEmblemShared)
+	col(tomo.IconEmblemSymbolicLink)
+	col(tomo.IconEmblemSynchronized)
+	col(tomo.IconEmblemSystem)
+	col(tomo.IconEmblemUnreadable)
+
+	row()
+	// places
+	col(tomo.IconPlaceDirectory)
+	col(tomo.IconPlaceRemote)
+	col(tomo.IconPlaceHome)
+	col(tomo.IconPlaceDownloads)
+	col(tomo.IconPlaceDesktop)
+	col(tomo.IconPlacePhotos)
+	col(tomo.IconPlaceBooks)
+	col(tomo.IconPlaceBookmarks)
+	col(tomo.IconPlaceTrash)
+	col(tomo.IconPlaceDocuments)
+	col(tomo.IconPlaceRepositories)
+	col(tomo.IconPlaceMusic)
+	col(tomo.IconPlaceArchives)
+	col(tomo.IconPlaceFonts)
+	col(tomo.IconPlaceBinaries)
+	col(tomo.IconPlaceVideos)
+	col(tomo.IconPlace3DObjects)
+	col(tomo.IconPlaceHistory)
+	col(tomo.IconPlacePreferences)
+
+	row()
+	// status: checkbox
+	col(tomo.IconCheckboxChecked)
+	col(tomo.IconCheckboxUnchecked)
+	// status: appointments
+	col(tomo.IconAppointmentMissed)
+	col(tomo.IconAppointmentSoon)
+	// status: dialogs
+	col(tomo.IconDialogError)
+	col(tomo.IconDialogInformation)
+	col(tomo.IconDialogPassword)
+	col(tomo.IconDialogQuestion)
+	col(tomo.IconDialogWarning)
+	// status: directories
+	col(tomo.IconDirectoryDragAccept)
+	col(tomo.IconDirectoryFull)
+	col(tomo.IconDirectoryOpen)
+	col(tomo.IconDirectoryVisiting)
+	// status: trash
+	col(tomo.IconTrashFull)
+	// status: resource
+	col(tomo.IconResourceLoading)
+	col(tomo.IconResourceMissing)
+	// status: mail
+	col(tomo.IconMailAttachment)
+	col(tomo.IconMailUnread)
+	col(tomo.IconMailReplied)
+	col(tomo.IconMailSigned)
+	col(tomo.IconMailSignedVerified)
+
+	row()
+	// status: network
+	col(tomo.IconCellularSignal0)
+	col(tomo.IconCellularSignal1)
+	col(tomo.IconCellularSignal2)
+	col(tomo.IconCellularSignal3)
+	col(tomo.IconWirelessSignal0)
+	col(tomo.IconWirelessSignal1)
+	col(tomo.IconWirelessSignal2)
+	col(tomo.IconWirelessSignal3)
+	col(tomo.IconNetworkError)
+	col(tomo.IconNetworkIdle)
+	col(tomo.IconNetworkOffline)
+	col(tomo.IconNetworkReceive)
+	col(tomo.IconNetworkTransmit)
+	col(tomo.IconNetworkTransmitReceive)
+	// status: print
+	col(tomo.IconPrintError)
+	col(tomo.IconPrintPrinting)
+	// status: security
+	col(tomo.IconSecurityHigh)
+	col(tomo.IconSecurityMedium)
+	col(tomo.IconSecurityLow)
+	// status: software
+	col(tomo.IconSoftwareUpdateAvailable)
+	col(tomo.IconSoftwareUpdateUrgent)
+	col(tomo.IconSoftwareInstalling)
+	// status: sync
+	col(tomo.IconSyncError)
+	col(tomo.IconSyncSynchronizing)
+	// status: tasks
+	col(tomo.IconTaskDue)
+	col(tomo.IconTaskPastDue)
+	// status: users
+	col(tomo.IconUserAvailable)
+	col(tomo.IconUserAway)
+	col(tomo.IconUserIdle)
+	col(tomo.IconUserOffline)
+
+	row()
+	// status: power
+	col(tomo.IconBattery0)
+	col(tomo.IconBattery1)
+	col(tomo.IconBattery2)
+	col(tomo.IconBattery3)
+	col(tomo.IconBrightness0)
+	col(tomo.IconBrightness1)
+	col(tomo.IconBrightness2)
+	col(tomo.IconBrightness3)
+	// status: media
+	col(tomo.IconVolume0)
+	col(tomo.IconVolume1)
+	col(tomo.IconVolume2)
+	col(tomo.IconVolume3)
+	col(tomo.IconPlaylistRepeat)
+	col(tomo.IconPlaylistShuffle)
+	// status: weather
+	col(tomo.IconWeatherClear)
+	col(tomo.IconWeatherClearNight)
+	col(tomo.IconWeatherFewClouds)
+	col(tomo.IconWeatherFewCloudsNight)
+	col(tomo.IconWeatherFog)
+	col(tomo.IconWeatherOvercast)
+	col(tomo.IconWeatherSevereAlert)
+	col(tomo.IconWeatherShowers)
+	col(tomo.IconWeatherShowersScattered)
+	col(tomo.IconWeatherSnow)
+	col(tomo.IconWeatherStorm)
+	
+	return source
+}
+
+type iconTheme struct {
+	texturesSmall map[tomo.Icon] canvas.Texture
+	texturesLarge map[tomo.Icon] canvas.Texture
+}
+
+// New creates a new fallback icon theme.
+func New () tomo.Icons {
+	return new(iconTheme)
+}
+
+func (this *iconTheme) ensure () {
+	if this.texturesSmall != nil { return }
+	this.texturesSmall = generateSource(atlasSmallBytes, 16)
+	this.texturesLarge = generateSource(atlasLargeBytes, 32)
+}
+
+func (this *iconTheme) selectSource (size tomo.IconSize) map[tomo.Icon] canvas.Texture {
+	if size == tomo.IconSizeSmall {
+		return this.texturesSmall
+	} else {
+		return this.texturesLarge
+	}
+}
+
+func (this *iconTheme) Icon (icon tomo.Icon, size tomo.IconSize) canvas.Texture {
+	this.ensure()
+	source := this.selectSource(size)
+	if texture, ok := source[icon]; ok {
+		return texture
+	}
+	return nil
+}
+
+func (this *iconTheme) MimeIcon (mime data.Mime, size tomo.IconSize) canvas.Texture {
+	this.ensure()
+	source := this.selectSource(size)
+	if mime == data.M("inode", "directory") {
+		return source[tomo.IconPlaceDirectory]
+	} else {
+		return source[tomo.Icon("File")]
+	}
+}

internal/icons/xdg/icon.go

@@ -0,0 +1,182 @@
+package xdgIcons
+
+import "os"
+import "fmt"
+import "log"
+import "image"
+import "regexp"
+import "strings"
+import _ "image/png"
+import "git.tebibyte.media/tomo/tomo"
+import xdgIconTheme "git.tebibyte.media/tomo/xdg/icon-theme"
+import "git.tebibyte.media/tomo/tomo/data"
+import "git.tebibyte.media/tomo/tomo/canvas"
+
+type iconTheme struct {
+	xdg xdgIconTheme.Theme
+	fallback       tomo.Icons
+	texturesSmall  map[tomo.Icon] canvas.Texture
+	texturesMedium map[tomo.Icon] canvas.Texture
+	texturesLarge  map[tomo.Icon] canvas.Texture
+}
+
+func FindThemeWarn (name string, fallback tomo.Icons, path ...string) (tomo.Icons, error) {
+	this := &iconTheme {
+		fallback:       fallback,
+		texturesLarge:  make(map[tomo.Icon] canvas.Texture),
+		texturesMedium: make(map[tomo.Icon] canvas.Texture),
+		texturesSmall:  make(map[tomo.Icon] canvas.Texture),
+	}
+	
+	xdg, err := xdgIconTheme.FindThemeWarn(name, path...)
+	if err != nil { return nil, err }
+	this.xdg = xdg
+	
+	return this, nil
+}
+
+func (this *iconTheme) selectSource (size tomo.IconSize) map[tomo.Icon] canvas.Texture {
+	switch size {
+	case tomo.IconSizeMedium: return this.texturesMedium
+	case tomo.IconSizeLarge:  return this.texturesLarge
+	default:                  return this.texturesSmall
+	}
+}
+
+func (this *iconTheme) xdgIcon (name string, size tomo.IconSize) (canvas.Texture, bool) {
+	// TODO use scaling factor instead of 1
+	// find icon file
+	icon, err := this.xdg.FindIcon(name, iconSizePixels(size), 1, xdgIconTheme.PNG)
+	if err != nil { return nil, false }
+
+	// open icon file
+	iconFile, err := os.Open(icon.Path)
+	if err != nil {
+		// this failing indicates a broken icon theme
+		log.Printf("nasin: icon file '%s' is inaccessible: %v\n", icon.Path, err)
+		return nil, false
+	}
+
+	iconImage, _, err := image.Decode(iconFile)
+	if err != nil {
+		// this failing indicates a broken icon theme
+		log.Printf("nasin: icon file '%s' is broken: %v\n", icon.Path, err)
+		return nil, false
+	}
+
+	return tomo.NewTexture(iconImage), true
+}
+
+func (this *iconTheme) Icon (icon tomo.Icon, size tomo.IconSize) canvas.Texture {
+	source := this.selectSource(size)
+	texture, ok := source[icon]
+	if !ok {
+		texture = this.icon(icon, size)
+		source[icon] = texture
+	}
+
+	if texture == nil {
+		return this.fallback.Icon(icon, size)
+	} else {
+		return texture
+	}
+}
+
+func (this *iconTheme) MimeIcon (mime data.Mime, size tomo.IconSize) canvas.Texture {
+	icon := tomo.Icon(mime.String())
+	source := this.selectSource(size)
+	texture, ok := source[icon]
+	if !ok {
+		texture = this.mimeIcon(mime, size)
+		source[icon] = texture
+	}
+
+	if texture == nil {
+		return this.fallback.MimeIcon(mime, size)
+	} else {
+		return texture
+	}
+}
+
+func (this *iconTheme) icon (icon tomo.Icon, size tomo.IconSize) canvas.Texture {
+	if texture, ok := this.xdgIcon(XdgIconName(icon), size); ok {
+		return texture
+	}
+	if texture, ok := this.xdgIcon(XdgIconName(generalizeIcon(icon)), size); ok {
+		return texture
+	}
+	return nil
+}
+
+func (this *iconTheme) mimeIcon (mime data.Mime, size tomo.IconSize) canvas.Texture {
+	if texture, ok := this.xdgIcon(xdgFormatMime(mime), size); ok {
+		return texture
+	}
+	if texture, ok := this.xdgIcon(xdgFormatMime(generalizeMimeType(mime)), size); ok {
+		return texture
+	}
+	if texture, ok := this.xdgIcon(xdgFormatMime(data.M("text", "x-generic")), size); ok {
+		return texture
+	}
+	return nil
+}
+
+var kebabMatchFirstCap = regexp.MustCompile("(.)([A-Z][a-z]+)")
+var kebabMatchAllCaps  = regexp.MustCompile("([a-z0-9])([A-Z])")
+
+// XdgIconName returns the best XDG name for the given icon.
+func XdgIconName (icon tomo.Icon) string {
+	if name, ok := xdgIconNames[icon]; ok {
+		return name
+	}
+
+	name := kebabMatchFirstCap.ReplaceAllString(string(icon), "${1}-${2}")
+	name  = kebabMatchAllCaps.ReplaceAllString(string(name), "${1}-${2}")
+	return strings.ToLower(name)
+}
+
+func generalizeIcon (icon tomo.Icon) tomo.Icon {
+	name := string(icon)
+	switch {
+	case strings.HasPrefix(name, "Application"): return tomo.IconApplication
+	case strings.HasPrefix(name, "Preferences"): return tomo.IconPreferences
+	case strings.HasPrefix(name, "Device"):      return tomo.IconDevice
+	case strings.HasPrefix(name, "Hardware"):    return tomo.IconHardware
+	case strings.HasPrefix(name, "Storage"):     return tomo.IconStorageHardDisk
+	case strings.HasPrefix(name, "Input"):       return tomo.IconInputMouse
+	case strings.HasPrefix(name, "Network"):     return tomo.IconNetworkWired
+	case strings.HasPrefix(name, "Place"):       return tomo.IconPlaceDirectory
+	case strings.HasPrefix(name, "Directory"):   return tomo.IconPlaceDirectory
+	case strings.HasPrefix(name, "Trash"):       return tomo.IconPlaceTrash
+	case strings.HasPrefix(name, "Help"):        return tomo.IconHelpContents
+	}
+
+	switch icon {
+	case tomo.IconCellularSignal0: return tomo.IconWirelessSignal0
+	case tomo.IconCellularSignal1: return tomo.IconWirelessSignal1
+	case tomo.IconCellularSignal2: return tomo.IconWirelessSignal2
+	case tomo.IconCellularSignal3: return tomo.IconWirelessSignal3
+	}
+
+	return icon
+}
+
+func xdgFormatMime (mime data.Mime) string {
+	return fmt.Sprintf("%s-%s", mime.Type, mime.Subtype)
+}
+
+func generalizeMimeType (mime data.Mime) data.Mime {
+	// FIXME make this more accurate
+	// https://specifications.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html
+	mime.Subtype = "x-generic"
+	return mime
+}
+
+func iconSizePixels (size tomo.IconSize) int {
+	// TODO: once Tomo has scaling support, take that into account here
+	switch size {
+	case tomo.IconSizeMedium: return 24
+	case tomo.IconSizeLarge:  return 48
+	default:                  return 16
+	}
+}

internal/icons/xdg/xdgiconname.go

@@ -0,0 +1,136 @@
+package xdgIcons
+
+import "git.tebibyte.media/tomo/tomo"
+
+// icons that can't be directly translated with regex
+var xdgIconNames = map[tomo.Icon] string {
+	tomo.IconUnknown:                      "image-missing",
+	tomo.IconFileNew:                      "document-new",
+	tomo.IconDirectoryNew:                 "folder-new",
+	tomo.IconFileOpen:                     "document-open",
+	tomo.IconFileOpenRecent:               "document-open-recent",
+	tomo.IconFilePageSetup:                "document-page-setup",
+	tomo.IconFilePrint:                    "document-print",
+	tomo.IconFilePrintPreview:             "document-print-preview",
+	tomo.IconFilePermissions:              "document-permissions",        // non-standard
+	tomo.IconFileProperties:               "document-properties",
+	tomo.IconFileRename:                   "document-rename",             // non-standard
+	tomo.IconFileRevert:                   "document-revert",
+	tomo.IconFileSave:                     "document-save",
+	tomo.IconFileSaveAs:                   "document-save-as",
+	tomo.IconFileSend:                     "document-send",
+	tomo.IconFormatAlignCenter:            "format-justify-center",
+	tomo.IconFormatAlignEven:              "format-justify-fill",
+	tomo.IconFormatAlignLeft:              "format-justify-left",
+	tomo.IconFormatAlignRight:             "format-justify-right",
+	tomo.IconMailReceive:                  "mail-send-receive",
+	tomo.IconValueIncrement:               "list-add",
+	tomo.IconValueDecrement:               "list-remove",
+	tomo.IconValueReset:                   "value-reset",                 // non-standard
+	tomo.IconApplication:                  "system-run",
+	tomo.IconApplicationWebBrowser:        "web-browser",
+	tomo.IconApplicationMesssanger:        "internet-messanger",          // non-standard
+	tomo.IconApplicationPhone:             "accessories-phone",           // non-standard
+	tomo.IconApplicationMail:              "internet-mail-client",        // non-standard
+	tomo.IconApplicationTerminalEmulator:  "utilities-terminal",
+	tomo.IconApplicationFileBrowser:       "system-file-manager",
+	tomo.IconApplicationTextEditor:        "accessories-text-editor",
+	tomo.IconApplicationDocumentViewer:    "office-document-viewer",      // non-standard
+	tomo.IconApplicationWordProcessor:     "office-word-processor",       // non-standard
+	tomo.IconApplicationSpreadsheet:       "office-spreadsheet",          // non-standard
+	tomo.IconApplicationSlideshow:         "office-slideshow",            // non-standard
+	tomo.IconApplicationCalculator:        "accessories-calculator",
+	tomo.IconApplicationPreferences:       "preferences-system",
+	tomo.IconApplicationProcessManager:    "utilities-system-monitor",
+	tomo.IconApplicationSystemInformation: "distributor-logo",            // non-standard
+	tomo.IconApplicationManual:            "help-browser",
+	tomo.IconApplicationCamera:            "accessories-camera",          // non-standard
+	tomo.IconApplicationImageViewer:       "graphics-image-viewer",       // non-standard
+	tomo.IconApplicationMediaPlayer:       "audio-video-media-player",    // non-standard
+	tomo.IconApplicationImageEditor:       "graphics-image-editor",       // non-standard
+	tomo.IconApplicationAudioEditor:       "audio-audio-editor",          // non-standard
+	tomo.IconApplicationVideoEditor:       "video-video-editor",          // non-standard
+	tomo.IconApplicationClock:             "accessories-clock",           // non-standard
+	tomo.IconApplicationCalendar:          "accessories-calendar",        // non-standard
+	tomo.IconApplicationChecklist:         "accessories-checklist",       // non-standard
+	tomo.IconApplications:                 "applications-other",
+	tomo.IconPreferences:                  "preferences-other",
+	tomo.IconPreferencesNetwork:           "preferences-system-network",
+	tomo.IconDevice:                       "device",                      // non-standard
+	tomo.IconDeviceCamera:                 "camera-photo",
+	tomo.IconDeviceWebCamera:              "camera-web",
+	tomo.IconDeviceComputer:               "computer",
+	tomo.IconDevicePda:                    "pda",
+	tomo.IconDevicePhone:                  "phone",
+	tomo.IconDevicePrinter:                "printer",
+	tomo.IconDeviceScanner:                "scanner",
+	tomo.IconDeviceMultimediaPlayer:       "multimedia-player",
+	tomo.IconDeviceVideoDisplay:           "video-display",
+	tomo.IconDeviceAudioInput:             "audio-input-microphone",
+	tomo.IconDeviceAudioOutput:            "audio-speakers",
+	tomo.IconHardware:                     "card",                        // non-standard
+	tomo.IconHardwareCPU:                  "cpu",
+	tomo.IconHardwareGPU:                  "video-card",
+	tomo.IconHardwareRAM:                  "ram",
+	tomo.IconHardwareSoundCard:            "audio-card",
+	tomo.IconHardwareNetworkAdapter:       "network-card",
+	tomo.IconPowerBattery:                 "battery",
+	tomo.IconStorageHardDisk:              "drive-harddisk",
+	tomo.IconStorageFloppyDisk:            "media-floppy",
+	tomo.IconStorageSolidState:            "drive-solid",
+	tomo.IconStorageOptical:               "media-optical",
+	tomo.IconStorageFlashStick:            "media-removable",
+	tomo.IconStorageFlashCard:             "media-flash",
+	tomo.IconStorageMagneticTape:          "media-tape",
+	tomo.IconEmblemReadOnly:               "emblem-readonly",
+	tomo.IconPlaceDirectory:               "folder",
+	tomo.IconPlaceRemote:                  "folder-remote",
+	tomo.IconPlaceHome:                    "user-home",
+	tomo.IconPlaceDownloads:               "folder-downloads",            // common
+	tomo.IconPlaceDesktop:                 "user-desktop",
+	tomo.IconPlacePhotos:                  "folder-pictures",             // common
+	tomo.IconPlaceBooks:                   "folder-books",                // non-standard
+	tomo.IconPlaceBookmarks:               "user-bookmarks",
+	tomo.IconPlaceTrash:                   "user-trash",
+	tomo.IconPlaceDocuments:               "folder-documents",            // common
+	tomo.IconPlaceRepositories:            "folder-repositories",         // non-standard
+	tomo.IconPlaceMusic:                   "folder-music",                // common
+	tomo.IconPlaceArchives:                "folder-archives",             // non-standard
+	tomo.IconPlaceFonts:                   "folder-fonts",                // non-standard
+	tomo.IconPlaceBinaries:                "folder-executables",          // non-standard
+	tomo.IconPlaceVideos:                  "folder-videos",               // common
+	tomo.IconPlace3DObjects:               "folder-3d-objects",           // non-standard
+	tomo.IconPlaceHistory:                 "folder-history",              // non-standard
+	tomo.IconPlacePreferences:             "preferences-other",
+	tomo.IconDirectoryDragAccept:          "folder-drag-accept",
+	tomo.IconDirectoryFull:                "folder-full",
+	tomo.IconDirectoryOpen:                "folder-open",
+	tomo.IconDirectoryVisiting:            "folder-visiting",
+	tomo.IconTrashFull:                    "user-trash-full",
+	tomo.IconResourceLoading:              "image-loading",
+	tomo.IconResourceMissing:              "image-missing",
+	tomo.IconCellularSignal0:              "nm-signal-00",                // common
+	tomo.IconCellularSignal1:              "nm-signal-25",                // common
+	tomo.IconCellularSignal2:              "nm-signal-75",                // common
+	tomo.IconCellularSignal3:              "nm-signal-100",               // common
+	tomo.IconWirelessSignal0:              "wifi-signal-00",              // common
+	tomo.IconWirelessSignal1:              "wifi-signal-25",              // common
+	tomo.IconWirelessSignal2:              "wifi-signal-75",              // common
+	tomo.IconWirelessSignal3:              "wifi-signal-100",             // common
+	tomo.IconPrintError:                   "printer-error",
+	tomo.IconPrintPrinting:                "printer-printing",
+	tomo.IconBattery0:                     "battery-caution",
+	tomo.IconBattery1:                     "battery-low",
+	tomo.IconBattery2:                     "battery-good",                // common
+	tomo.IconBattery3:                     "battery-full",                // common
+	tomo.IconBrightness0:                  "brightness-dim",              // non-standard
+	tomo.IconBrightness1:                  "brightness-medium",           // non-standard
+	tomo.IconBrightness2:                  "brightness-bright",           // non-standard
+	tomo.IconBrightness3:                  "brightness-full",             // non-standard
+	tomo.IconVolume0:                      "audio-volume-muted",
+	tomo.IconVolume1:                      "audio-volume-low",
+	tomo.IconVolume2:                      "audio-volume-medium",
+	tomo.IconVolume3:                      "audio-volume-high",
+	tomo.IconPlaylistRepeat:               "media-playlist-repeat",
+	tomo.IconPlaylistShuffle:              "media-playlist-shuffle",
+}

internal/registrar/doc.go

@@ -0,0 +1,2 @@
+// Package registrar provides platform-dependent components at compile time.
+package registrar

internal/registrar/registrar_unix.go

@@ -0,0 +1,43 @@
+//go:build unix && (!darwin)
+package registrar
+
+import "os"
+import "log"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/backend/x"
+import "git.tebibyte.media/tomo/nasin/internal/style"
+import "git.tebibyte.media/tomo/nasin/internal/icons/xdg"
+import "git.tebibyte.media/tomo/nasin/internal/icons/fallback"
+import "git.tebibyte.media/tomo/nasin/internal/style/fallback"
+import "git.tebibyte.media/tomo/nasin/internal/style/aluminum"
+
+func RegisterBackend () error {
+	tomo.Register(1, x.New)
+	return nil
+}
+
+func SetTheme () error {
+	var styl *style.Style
+	// TODO eventually get rid of this when we make a file format for
+	// storing visual styles
+	if os.Getenv("TOMO_USE_ALUMINUM_STYLE") != "" {
+		styl = aluminumStyle.New()
+	} else {
+		styl = fallbackStyle.New()
+	}
+	icons := fallbackIcons.New()
+	
+	iconThemeName := os.Getenv("TOMO_XDG_ICON_THEME")
+	if iconThemeName != "" {
+		xdgIconTheme, err := xdgIcons.FindThemeWarn(iconThemeName, icons)
+		if err == nil {
+			icons = xdgIconTheme
+		} else {
+			log.Printf("nasin: could not load icon theme '%s': %v", iconThemeName, err)
+		}
+	}
+	
+	tomo.SetStyle(styl)
+	tomo.SetIcons(icons)
+	return nil	
+}

internal/style/aluminum/aluminum.go

@@ -0,0 +1,19 @@
+package aluminumStyle
+
+import "image/color"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/nasin/internal/style"
+
+// New returns Aluminum, a futuristic, bluish-white style.
+func New () *style.Style {
+	return &style.Style {
+		Colors: map[tomo.Color] color.Color {
+			tomo.ColorBackground: colorBackground,
+			tomo.ColorForeground: colorForeground,
+			tomo.ColorRaised:     colorRaised,
+			tomo.ColorSunken:     colorSunken,
+			tomo.ColorAccent:     colorFocus,
+		},
+		Rules: rules,
+	}
+}

internal/style/aluminum/style.go

@@ -0,0 +1,392 @@
+package aluminumStyle
+
+import "image/color"
+import "git.tebibyte.media/tomo/tomo"
+import "golang.org/x/image/font/basicfont"
+import "git.tebibyte.media/tomo/nasin/internal/style"
+
+func hex (color uint32) (c color.RGBA) {
+	c.A = uint8(color)
+	c.B = uint8(color >>  8)
+	c.G = uint8(color >> 16)
+	c.R = uint8(color >> 24)
+	return
+}
+
+func border (top, right, bottom, left uint32, width ...int) tomo.Border {
+	return tomo.Border {
+		Width: tomo.I(width...),
+		Color: [4]color.Color {
+			hex(top),    hex(right),
+			hex(bottom), hex(left),
+		},
+	}
+}
+
+var colorDot                   = hex(0x7391c080)
+var colorFocus                 = hex(0x5f8bc4FF)
+var colorHighlight             = hex(0x5f8bc4FF)
+var colorBackground            = hex(0xd4d4d4FF)
+var colorForeground            = color.Black
+
+var colorOutline               = color.Black
+var colorGutter                = hex(0xbfc6d1FF)
+var colorGutterHovered         = hex(0xc5cbd6FF)
+var colorRaised                = hex(0xe9eaeaFF)
+var colorRaisedPressed         = hex(0xccd4ddFF)
+var colorRaisedFocused         = hex(0xcfd6ddFF)
+var colorRaisedHovered         = hex(0xf1f3f5FF)
+var colorSunken                = hex(0xe9eaeaFF)
+var colorSunkenFocused         = hex(0xe0e6eeFF)
+var colorSunkenPressed         = hex(0xe0e6eeFF)
+var colorCalendarWeekdayHeader = hex(0xd3cac2FF)
+var colorCalendarWeekend       = hex(0xc2d3c4FF)
+var colorCalendarDay           = hex(0xd6dae2FF)
+
+var outline = tomo.Border {
+	Width: tomo.I(1),
+	Color: [4]color.Color {
+		colorOutline,
+		colorOutline,
+		colorOutline,
+		colorOutline,
+	},
+}
+
+var borderEngraved       = border(0xc3c3c5FF, 0xe3e3e3FF, 0xe9e9e9ff, 0xc2c2c2ff, 1)
+var borderGap            = border(0x697c7cFF, 0x566767FF, 0x566767ff, 0x697c7cff, 1)
+var borderLifted         = border(0xf9fafcFF, 0xc2c8d3FF, 0xa4afc0ff, 0xf5f6f8ff, 1)
+var borderLiftedFocused  = border(0xf0f4f9FF, 0xb1bacaFF, 0x9aa6b7ff, 0xe4e9eeff, 1)
+var borderFocused        = border(0x5f8bc4FF, 0x5f8bc4FF, 0x5f8bc4ff, 0x5f8bc4ff, 1)
+var borderTear           = borderEngraved
+var borderTearFocused    = border(0x7f94b5FF, 0xced7e4FF, 0xced7e4FF, 0x7f94b5FF, 1)
+var borderTearPad        = border(0x00000000, 0x00000000, 0x00000000, 0x00000000, 3)
+var borderTearPadFocused = border(0x7391c080, 0x7391c080, 0x7391c080, 0x7391c080, 3)
+var borderInnerShadow    = border(0xa4afc0FF, 0xa4afc0FF, 0xa4afc0ff, 0xa4afc0ff, 1, 0, 0, 1)
+var borderOuterShadow    = border(0xa4afc0FF, 0xa4afc0FF, 0xa4afc0ff, 0xa4afc0ff, 0, 1, 1, 0)
+
+var rules = []style.Rule {
+	// *.*[*]
+	style.Rule {
+		Default: style.AS (
+			style.AttrFace      { Face:  basicfont.Face7x13    },
+			style.AttrTextColor { Color: tomo.ColorForeground  },
+			style.AttrDotColor  { Color: colorDot              },
+			style.AttrGap       { X: 8, Y: 8                   },
+		),
+	},
+
+	// *.Button[*]
+	style.Rule {
+		Role: tomo.R("", "Button", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderLifted,
+			},
+			style.AttrPadding(tomo.I(4, 8)),
+			style.AttrColor { Color: tomo.ColorRaised },
+		),
+		Pressed: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrPadding(tomo.I(5, 8, 4, 9)),
+			style.AttrColor { Color: colorRaisedPressed },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderLiftedFocused,
+			},
+			style.AttrPadding(tomo.I(4, 8)),
+			style.AttrColor { Color: colorRaisedFocused },
+		),
+		Hovered: style.AS (
+			style.AttrColor { Color: colorRaisedHovered },
+		),
+	},
+
+	// *.TextInput[*]
+	style.Rule {
+		Role: tomo.R("", "TextInput", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(5, 4, 4, 5)),
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderFocused,
+				borderInnerShadow,
+			},
+		),
+	},
+
+	// *.TextView[*]
+	style.Rule {
+		Role: tomo.R("", "TextView", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+	
+	// *.NumberInput[*]
+	style.Rule {
+		Role: tomo.R("", "NumberInput", ""),
+		Default: style.AS (
+			style.AttrGap { },
+		),
+	},
+
+	// *.Container[sunken]
+	style.Rule {
+		Role: tomo.R("", "Container", "sunken"),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+
+	// *.Container[outer]
+	style.Rule {
+		Role: tomo.R("", "Container", "outer"),
+		Default: style.AS (
+			style.AttrColor { Color: tomo.ColorBackground },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+
+	// *.Container[menu]
+	style.Rule {
+		Role: tomo.R("", "Container", "menu"),
+		Default: style.AS (
+			style.AttrBorder {
+				borderGap,
+				borderLifted,
+			},
+			style.AttrColor { Color: tomo.ColorBackground },
+			style.AttrGap { },
+		),
+	},
+
+	// *.Heading[*]
+	style.Rule {
+		Role: tomo.R("", "Heading", ""),
+		Default: style.AS (
+			style.AttrAlign { X: tomo.AlignMiddle, Y: tomo.AlignMiddle },
+		),
+	},
+
+	// *.Separator[*]
+	style.Rule {
+		Role: tomo.R("", "Separator", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+			},
+		),
+	},
+
+	// *.Slider[*]
+	style.Rule {
+		Role: tomo.R("", "Slider", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrColor { Color: colorGutter },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderFocused,
+				borderInnerShadow,
+			},
+		),
+		Hovered: style.AS (
+			style.AttrColor { Color: colorGutterHovered },
+		),
+	},
+	
+	// *.Slider[horizontal]
+	style.Rule {
+		Role: tomo.R("", "Slider", "horizontal"),
+		Default: style.AS(style.AttrMinimumSize { X: 48 }),
+	},
+	
+	// *.Slider[vertical]
+	style.Rule {
+		Role: tomo.R("", "Slider", "vertical"),
+		Default: style.AS(style.AttrMinimumSize { Y: 48 }),
+	},
+
+	// *.SliderHandle[*]
+	style.Rule {
+		Role: tomo.R("", "SliderHandle", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderOuterShadow,
+				borderGap,
+				borderLifted,
+			},
+			style.AttrColor { Color: tomo.ColorRaised },
+			style.AttrMinimumSize { X: 12, Y: 12, },
+		),
+	},
+
+	// *.Checkbox[*]
+	style.Rule {
+		Role: tomo.R("", "Checkbox", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(0, 1, 1, 0)),
+			style.AttrMinimumSize { X: 19, Y: 19 },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderFocused,
+				borderInnerShadow,
+			},
+			style.AttrPadding(tomo.I(0)),
+			style.AttrColor { Color: colorSunkenFocused },
+		),
+	},
+
+	// *.LabelCheckbox[*]
+	style.Rule {
+		Role: tomo.R("", "LabelCheckbox", ""),
+		Default: style.AS (
+			style.AttrGap { X: 8, Y: 8 },
+		),
+	},
+
+	// *.MenuItem[*]
+	style.Rule {
+		Role: tomo.R("", "MenuItem", ""),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(4)),
+			style.AttrGap { X: 4, Y: 4 },
+			style.AttrColor { Color: color.Transparent },
+		),
+		Hovered: style.AS (
+			style.AttrColor { Color: colorDot },
+		),
+		Focused: style.AS (
+			style.AttrColor { Color: colorDot },
+		),
+	},
+
+	// *.File[*]
+	style.Rule {
+		Role: tomo.R("", "File", ""),
+		Default: style.AS (
+			style.AttrColor { Color: color.Transparent },
+		),
+		Focused: style.AS (
+			style.AttrColor { Color: colorDot },
+		),
+	},
+	
+	// *.TearLine[*]
+	style.Rule {
+		Role: tomo.R("", "TearLine", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderTearPad,
+				borderTear,
+			},
+		),
+		Hovered: style.AS (
+			style.AttrBorder {
+				borderTearPadFocused,
+				borderTearFocused,
+			},
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				borderTearPadFocused,
+				borderTearFocused,
+			},
+		),
+	},
+	
+	// *.Calendar[*]
+	style.Rule {
+		Role: tomo.R("", "Calendar", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderOuterShadow,
+				borderGap,
+			},
+			style.AttrColor { Color: tomo.ColorRaised },
+			style.AttrPadding(tomo.I(2)),
+			style.AttrGap { X: 2, Y: 2 },
+		),
+	},
+	
+	// *.CalendarGrid[*]
+	style.Rule {
+		Role: tomo.R("", "CalendarGrid", ""),
+		Default: style.AS (
+			style.AttrGap { X: 2, Y: 2 },
+		),
+	},
+	
+	// *.CalendarWeekdayHeader[*]
+	style.Rule {
+		Role: tomo.R("", "CalendarWeekdayHeader", ""),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrColor { Color: colorCalendarWeekdayHeader },
+		),
+	},
+	
+	// *.CalendarDay[weekday]
+	style.Rule {
+		Role: tomo.R("", "CalendarDay", "weekday"),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrMinimumSize { X: 32, Y: 32 },
+			style.AttrColor { Color: colorCalendarDay },
+		),
+	},
+
+	// *.CalendarDay[weekend]
+	style.Rule {
+		Role: tomo.R("", "CalendarDay", "weekend"),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrMinimumSize { X: 32, Y: 32 },
+			style.AttrColor { Color: colorCalendarWeekend },
+		),
+	},
+}

internal/style/attribute.go

@@ -0,0 +1,41 @@
+package style
+
+import "image"
+import "image/color"
+import "golang.org/x/image/font"
+import "git.tebibyte.media/tomo/tomo"
+
+// Attr modifies one thing about an Objects's style.
+type Attr interface { attr () int }
+
+// AttrColor sets the background color of an Objects.
+type AttrColor struct { color.Color }
+// AttrTexture sets the texture of an Objects to a named texture.
+type AttrTexture string
+// AttrBorder sets the border of an Objects.
+type AttrBorder []tomo.Border
+// AttrMinimumSize sets the minimum size of an Objects.
+type AttrMinimumSize image.Point
+// AttrPadding sets the inner padding of an Objects.
+type AttrPadding tomo.Inset
+// AttrGap sets the gap between child Objects, if the Object is a ContainerBox.
+type AttrGap image.Point
+// AttrTextColor sets the text color, if the Object is a TextBox.
+type AttrTextColor struct { color.Color }
+// AttrDotColor sets the text selection color, if the Object is a TextBox.
+type AttrDotColor struct { color.Color }
+// AttrFace sets the font face, if the Object is a TextBox.
+type AttrFace struct { font.Face }
+// AttrAlign sets the alignment, if the Object is a ContentBox.
+type AttrAlign struct { X, Y tomo.Align }
+
+func (AttrColor)       attr () int { return 0 }
+func (AttrTexture)     attr () int { return 1 }
+func (AttrBorder)      attr () int { return 2 }
+func (AttrMinimumSize) attr () int { return 3 }
+func (AttrPadding)     attr () int { return 4 }
+func (AttrGap)         attr () int { return 5 }
+func (AttrTextColor)   attr () int { return 6 }
+func (AttrDotColor)    attr () int { return 7 }
+func (AttrFace)        attr () int { return 8 }
+func (AttrAlign)       attr () int { return 9 }

internal/style/fallback/style.go

@@ -0,0 +1,558 @@
+package fallbackStyle
+
+import "image/color"
+import "git.tebibyte.media/tomo/tomo"
+import "golang.org/x/image/font/basicfont"
+import "git.tebibyte.media/tomo/nasin/internal/style"
+
+var colorFocus                 = color.RGBA { R:  61, G: 128, B: 143, A: 255 }
+var colorInput                 = color.RGBA { R: 208, G: 203, B: 150, A: 255 }
+var colorCarved                = color.RGBA { R: 151, G: 160, B: 150, A: 255 }
+var colorGutter                = color.RGBA { R: 116, G: 132, B: 126, A: 255 }
+var colorShadow                = color.RGBA { R:  57, G:  59, B:  57, A: 255 }
+var colorShade                 = color.RGBA {                         A: 128 }
+var colorInputShadow           = color.RGBA { R: 143, G: 146, B:  91, A: 255 }
+var colorHighlight             = color.RGBA { R: 207, G: 215, B: 210, A: 255 }
+var colorBackground            = color.RGBA { R: 169, G: 171, B: 168, A: 255 }
+var colorCarvedPressed         = color.RGBA { R: 129, G: 142, B: 137, A: 255 }
+var colorForeground            = color.Black
+var colorOutline               = color.Black
+var colorCalendarWeekdayHeader = color.RGBA { R: 194, G: 162, B: 132, A: 255 }
+var colorCalendarWeekend       = color.RGBA { R: 165, G: 185, B: 120, A: 255 }
+var colorCalendarDay           = color.RGBA { R: 194, G: 189, B: 132, A: 255 }
+var colorInactive              = color.RGBA { R: 131, G: 147, B: 134, A: 255 }
+
+var outline = tomo.Border {
+	Width: tomo.I(1),
+	Color: [4]color.Color {
+		colorOutline,
+		colorOutline,
+		colorOutline,
+		colorOutline,
+	},
+}
+
+var borderColorOutline  = [4]color.Color { colorOutline,     colorOutline,   colorOutline,   colorOutline     }
+var borderColorEngraved = [4]color.Color { colorShadow,      colorHighlight, colorHighlight, colorShadow      }
+var borderColorLifted   = [4]color.Color { colorHighlight,   colorShadow,    colorShadow,    colorHighlight   }
+var borderColorInput    = [4]color.Color { colorInputShadow, colorInput,     colorInput,     colorInputShadow }
+var borderColorFocused  = [4]color.Color { colorFocus,       colorFocus,     colorFocus,     colorFocus       }
+var borderColorShade    = [4]color.Color { colorShade,       colorShade,     colorShade,     colorShade       }
+
+var rules = []style.Rule {
+	// *.*[*]
+	style.Rule {
+		Default: style.AS (
+			style.AttrFace      { Face:  basicfont.Face7x13    },
+			style.AttrTextColor { Color: tomo.ColorForeground  },
+			style.AttrDotColor  { Color: tomo.ColorAccent      },
+			style.AttrGap       { X: 8, Y: 8                   },
+		),
+	},
+
+	// *.Button[*]
+	style.Rule {
+		Role: tomo.R("", "Button", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorLifted,
+				},
+			},
+			style.AttrPadding(tomo.I(4, 8)),
+			style.AttrColor { Color: tomo.ColorRaised },
+		),
+		Pressed: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrPadding(tomo.I(5, 8, 4, 9)),
+			style.AttrColor { Color: colorCarvedPressed },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorFocused,
+				},
+			},
+			style.AttrPadding(tomo.I(4, 8)),
+		),
+	},
+
+	// *.TextInput[*]
+	style.Rule {
+		Role: tomo.R("", "TextInput", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorInput,
+				},
+			},
+			style.AttrColor { Color: colorInput },
+			style.AttrPadding(tomo.I(5, 4, 4, 5)),
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorFocused,
+				},
+			},
+		),
+	},
+
+	// *.TextView[*]
+	style.Rule {
+		Role: tomo.R("", "TextView", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+	
+	// *.NumberInput[*]
+	style.Rule {
+		Role: tomo.R("", "NumberInput", ""),
+		Default: style.AS (
+			style.AttrGap { },
+		),
+	},
+
+	// *.Container[sunken]
+	style.Rule {
+		Role: tomo.R("", "Container", "sunken"),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+
+	// *.Container[outer]
+	style.Rule {
+		Role: tomo.R("", "Container", "outer"),
+		Default: style.AS (
+			style.AttrColor { Color: tomo.ColorBackground },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+
+	// *.Container[menu]
+	style.Rule {
+		Role: tomo.R("", "Container", "menu"),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorLifted,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorBackground },
+			style.AttrGap { },
+		),
+	},
+
+	// *.Heading[*]
+	style.Rule {
+		Role: tomo.R("", "Heading", ""),
+		Default: style.AS (
+			style.AttrAlign { X: tomo.AlignMiddle, Y: tomo.AlignMiddle },
+		),
+	},
+
+	// *.Separator[*]
+	style.Rule {
+		Role: tomo.R("", "Separator", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorEngraved,
+				},
+			},
+		),
+	},
+
+	// *.Slider[*]
+	style.Rule {
+		Role: tomo.R("", "Slider", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrColor { Color: colorGutter },
+			style.AttrPadding(tomo.I(0, 1, 1, 0)),
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorFocused,
+				},
+			},
+			style.AttrPadding(tomo.I(0)),
+		),
+	},
+	
+	// *.Slider[horizontal]
+	style.Rule {
+		Role: tomo.R("", "Slider", "horizontal"),
+		Default: style.AS(style.AttrMinimumSize { X: 48 }),
+	},
+	
+	// *.Slider[vertical]
+	style.Rule {
+		Role: tomo.R("", "Slider", "vertical"),
+		Default: style.AS(style.AttrMinimumSize { Y: 48 }),
+	},
+
+	// *.SliderHandle[*]
+	style.Rule {
+		Role: tomo.R("", "SliderHandle", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorLifted,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorRaised },
+			style.AttrMinimumSize { X: 12, Y: 12, },
+		),
+	},
+
+	// *.Checkbox[*]
+	style.Rule {
+		Role: tomo.R("", "Checkbox", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(0, 1, 1, 0)),
+			style.AttrMinimumSize { X: 19, Y: 19 },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorFocused,
+				},
+			},
+			style.AttrPadding(tomo.I(0)),
+		),
+	},
+
+	// *.MenuItem[*]
+	style.Rule {
+		Role: tomo.R("", "MenuItem", ""),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(4)),
+			style.AttrGap { X: 4, Y: 4 },
+			style.AttrColor { Color: color.Transparent },
+		),
+		Hovered: style.AS (
+			style.AttrColor { Color: tomo.ColorAccent },
+		),
+		Focused: style.AS (
+			style.AttrColor { Color: tomo.ColorAccent },
+		),
+	},
+
+	// *.File[*]
+	style.Rule {
+		Role: tomo.R("", "File", ""),
+		Default: style.AS (
+			style.AttrColor { Color: color.Transparent },
+		),
+		Focused: style.AS (
+			style.AttrColor { Color: tomo.ColorAccent },
+		),
+	},
+
+	// *.TearLine[*]
+	style.Rule {
+		Role: tomo.R("", "TearLine", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(3),
+					Color: [4]color.Color {
+						color.Transparent,
+						color.Transparent,
+						color.Transparent,
+						color.Transparent,
+					},
+				},
+			},
+			style.AttrColor { Color: tomo.ColorForeground },
+			style.AttrPadding(tomo.I(1, 0, 0, 1)),
+		),
+		Hovered: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(3),
+					Color: borderColorFocused,
+				},
+			},
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(3),
+					Color: borderColorFocused,
+				},
+			},
+		),
+	},
+	
+	// *.Calendar[*]
+	style.Rule {
+		Role: tomo.R("", "Calendar", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(0, 1, 1, 0),
+					Color: borderColorShade,
+				},
+				outline,
+			},
+			style.AttrColor { Color: colorInput },
+			style.AttrPadding(tomo.I(2)),
+			style.AttrGap { X: 2, Y: 2 },
+		),
+	},
+	
+	// *.CalendarGrid[*]
+	style.Rule {
+		Role: tomo.R("", "CalendarGrid", ""),
+		Default: style.AS (
+			style.AttrGap { X: 2, Y: 2 },
+		),
+	},
+	
+	// *.CalendarWeekdayHeader[*]
+	style.Rule {
+		Role: tomo.R("", "CalendarWeekdayHeader", ""),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrColor { Color: colorCalendarWeekdayHeader },
+		),
+	},
+	
+	// *.CalendarDay[weekday]
+	style.Rule {
+		Role: tomo.R("", "CalendarDay", "weekday"),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrMinimumSize { X: 32, Y: 32 },
+			style.AttrColor { Color: colorCalendarDay },
+		),
+	},
+
+	// *.CalendarDay[weekend]
+	style.Rule {
+		Role: tomo.R("", "CalendarDay", "weekend"),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrMinimumSize { X: 32, Y: 32 },
+			style.AttrColor { Color: colorCalendarWeekend },
+		),
+	},
+	
+	// *.TabbedContainer[*]
+	style.Rule {
+		Role: tomo.R("", "TabbedContainer", ""),
+		Default: style.AS (
+			style.AttrGap { },
+		),
+	},
+	
+	// *.TabRow[*]
+	style.Rule {
+		Role: tomo.R("", "TabRow", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(1, 1, 0, 1),
+					Color: borderColorOutline,
+				},
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrGap { X: 0, Y: 0 },
+			style.AttrColor { Color: colorGutter },
+			style.AttrPadding(tomo.I(1, 0, 0, 0)),
+		),
+	},
+	
+	// *.TabSpacer[left]
+	style.Rule {
+		Role: tomo.R("", "TabSpacer", "left"),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(0, 0, 1, 0),
+					Color: borderColorEngraved,
+				},
+				tomo.Border {
+					Width: tomo.I(0, 0, 1, 0),
+					Color: borderColorOutline,
+				},
+			},
+			style.AttrMinimumSize { X: 1 },
+		),
+	},
+	
+	// *.TabSpacer[right]
+	style.Rule {
+		Role: tomo.R("", "TabSpacer", "right"),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 0),
+					Color: [4]color.Color {
+						colorGutter, colorGutter,
+						colorGutter, colorGutter,
+					},
+				},
+				tomo.Border {
+					Width: tomo.I(0, 0, 1, 0),
+					Color: borderColorEngraved,
+				},
+				tomo.Border {
+					Width: tomo.I(0, 0, 1, 1),
+					Color: borderColorOutline,
+				},
+				tomo.Border {
+					Width: tomo.I(0, 0, 0, 1),
+					Color: borderColorShade,
+				},
+			},
+			style.AttrMinimumSize { X: 3 },
+		),
+	},
+	
+	// *.Tab[*]
+	style.Rule {
+		Role: tomo.R("", "Tab", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 0),
+					Color: [4]color.Color {
+						colorGutter, colorGutter,
+						colorGutter, colorGutter,
+					},
+				},
+				tomo.Border {
+					Width: tomo.I(0, 0, 1, 0),
+					Color: borderColorEngraved,
+				},
+				tomo.Border {
+					Width: tomo.I(1, 0, 1, 1),
+					Color: borderColorOutline,
+				},
+				tomo.Border {
+					Width: tomo.I(1, 1, 0, 1),
+					Color: borderColorLifted,
+				},
+			},
+			style.AttrPadding(tomo.I(4, 8, 4, 8)),
+			style.AttrColor { Color: tomo.ColorRaised },
+		),
+	},
+	
+	// *.Tab[active]
+	style.Rule {
+		Role: tomo.R("", "Tab", "active"),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorOutline,
+				},
+				tomo.Border {
+					Width: tomo.I(1, 1, 0, 1),
+					Color: borderColorLifted,
+				},
+			},
+			style.AttrPadding(tomo.I(4, 8, 4, 8)),
+			style.AttrColor { Color: tomo.ColorBackground },
+		),
+	},
+
+	// *.Swatch[*]
+	style.Rule {
+		Role: tomo.R("", "Swatch", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+			},
+			style.AttrMinimumSize { X: 19, Y: 19 },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorFocused,
+				},
+			},
+		),
+	},
+
+	// *.ColorPickerMap[*]
+	style.Rule {
+		Role: tomo.R("", "ColorPickerMap", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrMinimumSize { X: 128, Y: 128 },
+		),
+	},
+}

internal/style/fallback/wintergreen.go

@@ -0,0 +1,20 @@
+package fallbackStyle
+
+import "image/color"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/nasin/internal/style"
+
+// New returns Wintergreen, the default Tomo style. It is neutral-gray with
+// green and turquoise accents.
+func New () *style.Style {
+	return &style.Style {
+		Colors: map[tomo.Color] color.Color {
+			tomo.ColorBackground: colorBackground,
+			tomo.ColorForeground: colorForeground,
+			tomo.ColorRaised:     colorCarved,
+			tomo.ColorSunken:     colorCarved,
+			tomo.ColorAccent:     colorFocus,
+		},
+		Rules: rules,
+	}
+}

internal/style/missing.go

@@ -0,0 +1,24 @@
+package style
+
+import "image"
+import "image/color"
+
+type missingTexture int
+
+func (texture missingTexture) ColorModel () color.Model {
+	return color.RGBAModel
+}
+
+func (texture missingTexture) Bounds () image.Rectangle {
+	return image.Rect(0, 0, int(texture), int(texture))
+}
+
+func (texture missingTexture) At (x, y int) color.Color {
+	x /= 8
+	y /= 8
+	if (x + y) % 2 == 0 {
+		return color.RGBA { R: 0xFF, B: 0xFF, A: 0xFF }
+	} else {
+		return color.RGBA { A: 0xFF }
+	}
+}

internal/style/style.go

@@ -0,0 +1,239 @@
+// Package style provides a data-driven style implementation.
+package style
+
+import "image"
+import "image/color"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/tomo/event"
+import "git.tebibyte.media/tomo/tomo/input"
+import "git.tebibyte.media/tomo/tomo/canvas"
+
+// this is CSS's bastard child
+
+// Style allows the use of data to define a visual style.
+type Style struct {
+	// Textures maps texture names to image textures.
+	Textures map[string] image.Image
+	textures map[string] canvas.TextureCloser // private texture cache
+	missing  canvas.TextureCloser             // cache for "missing" texture
+	
+	// Rules determines which styles get applied to which Objects.
+	Rules []Rule
+
+	// Colors maps tomo.Color values to color.RGBA values.
+	Colors map[tomo.Color] color.Color
+}
+
+// Rule describes under what circumstances should certain style attributes be
+// active.
+type Rule struct {
+	Role tomo.Role
+	Default AttrSet
+	Hovered AttrSet
+	Pressed AttrSet
+	Focused AttrSet
+}
+
+// AttrSet is a set of attributes wherein only one/zero of each attribute type
+// can exist. I deserve to be imprisoned for the way I made this work (look in
+// attribute.go). Its zero value can be used safely, and you can copy it if you
+// want, but it will point to the same set of attributes.
+type AttrSet struct {
+	set map[int] Attr
+}
+
+// AS builds an AttrSet out of a vararg list of Attr values.
+func AS (attrs ...Attr) AttrSet {
+	set := AttrSet { }
+	set.Add(attrs...)
+	return set
+}
+
+// Add adds attributes to the set.
+func (this *AttrSet) Add (attrs ...Attr) {
+	this.ensure()
+	for _, attr := range attrs {
+		this.set[attr.attr()] = attr
+	}
+}
+
+// MergeUnder takes attributes from another set and adds them if they don't
+// already exist in this one.
+func (this *AttrSet) MergeUnder (other AttrSet) {
+	this.ensure()
+	if other.set == nil { return }
+	for _, attr := range other.set {
+		if _, exists := this.set[attr.attr()]; !exists {
+			this.Add(attr)
+		}
+	}
+}
+
+// MergeOver takes attributes from another set and adds them, overriding this
+// one.
+func (this *AttrSet) MergeOver (other AttrSet) {
+	this.ensure()
+	if other.set == nil { return }
+	for _, attr := range other.set {
+		this.Add(attr)
+	}
+}
+
+func (this *AttrSet) ensure () {
+	if this.set == nil { this.set = make(map[int] Attr) }
+}
+
+func (this *Style) execute (object tomo.Object, set AttrSet) {
+	box := object.GetBox()
+	
+	for _, attr := range set.set {
+		switch attr := attr.(type) {
+		case AttrColor:
+			box.SetColor(attr.Color)
+		case AttrTexture:
+			box.SetTextureTile(this.texture(string(attr)))
+		case AttrBorder:
+			box.SetBorder([]tomo.Border(attr)...)
+		case AttrMinimumSize:
+			box.SetMinimumSize(image.Point(attr))
+		case AttrPadding:
+			box.SetPadding(tomo.Inset(attr))
+		case AttrGap:
+			if box, ok := box.(tomo.ContainerBox); ok {
+				box.SetGap(image.Point(attr))
+			}
+		case AttrTextColor:
+			if box, ok := box.(tomo.TextBox); ok {
+				box.SetTextColor(attr.Color)
+			}
+		case AttrDotColor:
+			if box, ok := box.(tomo.TextBox); ok {
+				box.SetDotColor(attr.Color)
+			}
+		case AttrFace:
+			if box, ok := box.(tomo.TextBox); ok {
+				box.SetFace(attr)
+			}
+		case AttrAlign:
+			if box, ok := box.(tomo.ContentBox); ok {
+				box.SetAlign(attr.X, attr.Y)
+			}
+		default:
+			panic("bug: nasin/internal/tomo.Theme: unexpected attribute")
+		}
+	}
+}
+
+func (this *Style) texture (name string) canvas.Texture {
+	this.ensureTextureCache()
+	if texture, ok := this.textures[name]; ok {
+		return texture
+	}
+	if this.Textures == nil {
+		if source, ok := this.Textures[name]; ok {
+			texture := tomo.NewTexture(source)
+			this.textures[name] = texture
+			return texture
+		}
+	}
+	return this.missingTexture()
+}
+
+func (this *Style) missingTexture () canvas.Texture {
+	if this.missing == nil {
+		this.missing = tomo.NewTexture(missingTexture(16))
+	}
+	return this.missing
+}
+
+func (this *Style) ensureTextureCache () {
+	if this.textures == nil { this.textures = make(map[string] canvas.TextureCloser) }
+}
+
+// setsFor builds flattened attr sets for a specific role based on the rules list
+func (this *Style) setsFor (role tomo.Role) (defaul, hovered, pressed, focused AttrSet) {
+	for _, current := range this.Rules {
+		// check for a match
+		packageMatch := current.Role.Package == role.Package || current.Role.Package == ""
+		objectMatch  := current.Role.Object  == role.Object  || current.Role.Object  == ""
+		variantMatch := current.Role.Variant == role.Variant || current.Role.Variant == ""
+		if packageMatch && objectMatch && variantMatch {
+			// if found, merge and override
+			defaul.MergeOver(current.Default)
+			hovered.MergeOver(current.Hovered)
+			pressed.MergeOver(current.Pressed)
+			focused.MergeOver(current.Focused)
+		}
+	}
+
+	// hovered and pressed are mutually exclusive states, so we compress
+	// them with the default state.
+	hovered.MergeUnder(defaul)
+	pressed.MergeUnder(defaul)
+	return defaul, hovered, pressed, focused
+}
+
+func (this *Style) Apply (object tomo.Object) event.Cookie {
+	pressed := false
+	hovered := false
+	box  := object.GetBox()
+	role := box.Role()
+
+	defaultSet, hoveredSet, pressedSet, focusedSet := this.setsFor(role)
+
+	updateStyle := func () {
+		if pressed {
+			this.execute(object, pressedSet)
+		} else if hovered {
+			this.execute(object, hoveredSet)
+		} else {
+			this.execute(object, defaultSet)
+		}
+		if box.Focused() && !pressed {
+			this.execute(object, focusedSet)
+		}
+	}
+	updateStyle()
+	
+	return event.MultiCookie (
+		box.OnFocusEnter(updateStyle),
+		box.OnFocusLeave(updateStyle),
+		box.OnMouseDown(func (button input.Button) {
+			if button != input.ButtonLeft { return }
+			pressed = true
+			updateStyle()
+		}),
+		box.OnMouseUp(func (button input.Button) {
+			if button != input.ButtonLeft { return }
+			pressed = false
+			updateStyle()
+		}),
+		box.OnMouseEnter(func () {
+			hovered = true
+			updateStyle()
+		}),
+		box.OnMouseLeave(func () {
+			hovered = false
+			updateStyle()
+		}))
+
+}
+
+func (this *Style) RGBA (c tomo.Color) (r, g, b, a uint32) {
+	if this.Colors == nil { return 0xFFFF, 0, 0xFFFF, 0xFFFF }
+	color, ok := this.Colors[c]
+	if !ok { return 0xFFFF, 0, 0xFFFF, 0xFFFF }
+	return color.RGBA()
+}
+
+// Close closes all cached textures this style has open. Do not call this while
+// the style is in use.
+func (this *Style) Close () error {
+	this.missing.Close()
+	this.missing = nil
+	for _, texture := range this.textures {
+		texture.Close()
+	}
+	this.textures = nil
+	return nil
+}

path.go

@@ -1,190 +1,32 @@
 package nasin
 
-import "io"
 import "os"
-import "io/fs"
-import "strings"
 import "path/filepath"
 
-// FS is Tomo's implementation of fs.FS. It provides access to a specific part
+// ApplicationUserDataDir returns the directory path where an application can
-// of the filesystem.
+// store its user data files. If the directory does not exist, it will be
-type FS struct {
+// created.
-	path string
+func ApplicationUserDataDir (app ApplicationDescription) (string, error) {
+	return userMkdirAll(app.ID, userDataDir)
 }
 
-// FileWriter is a writable version of fs.File.
+// ApplicationUserConfigDir returns the directory path where an application can
-type FileWriter interface {
+// store its user configuration files.
-	fs.File
+func ApplicationUserConfigDir (app ApplicationDescription) (string, error) {
-	io.Writer
+	return userMkdirAll(app.ID, userConfigDir)
 }
 
-// ApplicationUserDataFS returns an FS that an application can use to store user
+// ApplicationUserCacheDir returns the directory path where an application can
-// data files.
+// store its user cache files.
-func ApplicationUserDataFS (app ApplicationDescription) (*FS, error) {
+func ApplicationUserCacheDir (app ApplicationDescription) (string, error) {
-	dataDir, err := userDataDir()
+	return userMkdirAll(app.ID, userCacheDir)
-	if err != nil { return nil, err }
-	return appFs(dataDir, app)
 }
 
-// ApplicationUserConfigFS returns an FS that an application can use to store
+func userMkdirAll (sub string, getter func () (string, error)) (string, error) {
-// user configuration files.
+	path, err := getter()
-func ApplicationUserConfigFS (app ApplicationDescription) (*FS, error) {
+	if err != nil { return "", err }
-	configDir, err := userConfigDir()
+	path = filepath.Join(path, sub)
-	if err != nil { return nil, err }
+	err = os.MkdirAll(path, 0700)
-	return appFs(configDir, app)
+	if err != nil { return "", err }
-}
+	return path, nil
-
-// ApplicationUserCacheFS returns an FS that an application can use to store
-// user cache files.
-func ApplicationUserCacheFS (app ApplicationDescription) (*FS, error) {
-	cacheDir, err := userCacheDir()
-	if err != nil { return nil, err }
-	return appFs(cacheDir, app)
-}
-
-func pathErr (op, path string, err error) error {
-	return &fs.PathError {
-		Op:   op,
-		Path: path,
-		Err:  err,
-	}
-}
-
-func appFs (root string, app ApplicationDescription) (*FS, error) {
-	// remove slashes
-	appid := app.ID
-	appid = strings.ReplaceAll(appid, "/", "-")
-	appid = strings.ReplaceAll(appid, "\\", "-")
-
-	path := filepath.Join(root, appid)
-
-	// ensure the directory actually exists
-	err := os.MkdirAll(path, 700)
-	if err != nil { return nil, err }
-
-	return &FS { path: path }, nil
-}
-
-func (this FS) subPath (name string) (string, error) {
-	if !fs.ValidPath(name)         { return "", fs.ErrInvalid }
-	if strings.Contains(name, "/") { return "", fs.ErrInvalid }
-	return filepath.Join(this.path, name), nil
-}
-
-// Open opens the named file.
-func (this FS) Open (name string) (fs.File, error) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("open", name, err)
-	}
-
-	return os.Open(path)
-}
-
-// Create creates or truncates the named file.
-func (this FS) Create (name string) (FileWriter, error) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("create", name, err)
-	}
-
-	return os.Create(path)
-}
-
-// OpenFile is the generalized open call; most users will use Open or Create
-// instead.
-func (this FS) OpenFile (
-	name string,
-	flag int,
-	perm os.FileMode,
-) (
-	FileWriter,
-	error,
-) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("open", name, err)
-	}
-
-	return os.OpenFile(path, flag, perm)
-}
-
-// ReadDir reads the named directory and returns a list of directory entries
-// sorted by filename.
-func (this FS) ReadDir (name string) ([]fs.DirEntry, error) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("readdir", name, err)
-	}
-
-	return os.ReadDir(path)
-}
-
-// ReadFile reads the named file and returns its contents.
-// A successful call returns a nil error, not io.EOF.
-// (Because ReadFile reads the whole file, the expected EOF
-// from the final Read is not treated as an error to be reported.)
-//
-// The caller is permitted to modify the returned byte slice.
-func (this FS) ReadFile (name string) ([]byte, error) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("readfile", name, err)
-	}
-
-	return os.ReadFile(path)
-}
-
-// WriteFile writes data to the named file, creating it if necessary.
-func (this FS) WriteFile (name string, data []byte, perm os.FileMode) error {
-	path, err := this.subPath(name)
-	if err != nil {
-		return pathErr("writefile", name, err)
-	}
-
-	return os.WriteFile(path, data, perm)
-}
-
-// Stat returns a FileInfo describing the file.
-func (this FS) Stat (name string) (fs.FileInfo, error) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("stat", name, err)
-	}
-
-	return os.Stat(path)
-}
-
-// Remove removes the named file or (empty) directory.
-func (this FS) Remove (name string) error {
-	path, err := this.subPath(name)
-	if err != nil {
-		return pathErr("remove", name, err)
-	}
-
-	return os.Remove(path)
-}
-
-// RemoveAll removes name and any children it contains.
-func (this FS) RemoveAll (name string) error {
-	path, err := this.subPath(name)
-	if err != nil {
-		return pathErr("removeall", name, err)
-	}
-
-	return os.RemoveAll(path)
-}
-
-// Rename renames (moves) oldname to newname.
-func (this FS) Rename (oldname, newname string) error {
-	oldpath, err := this.subPath(oldname)
-	if err != nil {
-		return pathErr("rename", oldname, err)
-	}
-	newpath, err := this.subPath(newname)
-	if err != nil {
-		return pathErr("rename", newname, err)
-	}
-
-	return os.Rename(oldpath, newpath)
 }