package basic import "image" import "git.tebibyte.media/sashakoshka/tomo" import "git.tebibyte.media/sashakoshka/tomo/theme" import "git.tebibyte.media/sashakoshka/tomo/artist" import "git.tebibyte.media/sashakoshka/tomo/textmanip" import "git.tebibyte.media/sashakoshka/tomo/elements/core" // TextBox is a single-line text input. type TextBox struct { *core.Core core core.CoreControl enabled bool selected bool cursor int scroll int placeholder string text []rune placeholderDrawer artist.TextDrawer valueDrawer artist.TextDrawer onKeyDown func (key tomo.Key, modifiers tomo.Modifiers) (handled bool) onChange func () onSelectionRequest func () (granted bool) onSelectionMotionRequest func (tomo.SelectionDirection) (granted bool) onScrollBoundsChange func () } // NewTextBox creates a new text box with the specified placeholder text, and // a value. When the value is empty, the placeholder will be displayed in gray // text. func NewTextBox (placeholder, value string) (element *TextBox) { element = &TextBox { enabled: true } element.Core, element.core = core.NewCore(element) element.placeholderDrawer.SetFace(theme.FontFaceRegular()) element.valueDrawer.SetFace(theme.FontFaceRegular()) element.placeholder = placeholder element.placeholderDrawer.SetText([]rune(placeholder)) element.updateMinimumSize() element.SetValue(value) return } func (element *TextBox) Resize (width, height int) { element.core.AllocateCanvas(width, height) element.scrollToCursor() element.draw() if element.onScrollBoundsChange != nil { element.onScrollBoundsChange() } } func (element *TextBox) HandleMouseDown (x, y int, button tomo.Button) { if !element.enabled { return } element.Select() } func (element *TextBox) HandleMouseUp (x, y int, button tomo.Button) { } func (element *TextBox) HandleMouseMove (x, y int) { } func (element *TextBox) HandleMouseScroll (x, y int, deltaX, deltaY float64) { } func (element *TextBox) HandleKeyDown(key tomo.Key, modifiers tomo.Modifiers) { if element.onKeyDown != nil && element.onKeyDown(key, modifiers) { return } scrollMemory := element.scroll altered := true textChanged := false switch { case key == tomo.KeyBackspace: if len(element.text) < 1 { break } element.text, element.cursor = textmanip.Backspace ( element.text, element.cursor, modifiers.Control) textChanged = true case key == tomo.KeyDelete: if len(element.text) < 1 { break } element.text, element.cursor = textmanip.Delete ( element.text, element.cursor, modifiers.Control) textChanged = true case key == tomo.KeyLeft: element.cursor = textmanip.MoveLeft ( element.text, element.cursor, modifiers.Control) case key == tomo.KeyRight: element.cursor = textmanip.MoveRight ( element.text, element.cursor, modifiers.Control) case key.Printable(): element.text, element.cursor = textmanip.Type ( element.text, element.cursor, rune(key)) textChanged = true default: altered = false } if textChanged { element.runOnChange() element.valueDrawer.SetText(element.text) } if altered { element.scrollToCursor() } if (textChanged || scrollMemory != element.scroll) && element.onScrollBoundsChange != nil { element.onScrollBoundsChange() } if altered && element.core.HasImage () { element.draw() element.core.DamageAll() } } func (element *TextBox) HandleKeyUp(key tomo.Key, modifiers tomo.Modifiers) { } func (element *TextBox) Selected () (selected bool) { return element.selected } func (element *TextBox) Select () { if element.onSelectionRequest != nil { element.onSelectionRequest() } } func (element *TextBox) HandleSelection ( direction tomo.SelectionDirection, ) ( accepted bool, ) { direction = direction.Canon() if !element.enabled { return false } if element.selected && direction != tomo.SelectionDirectionNeutral { return false } element.selected = true if element.core.HasImage() { element.draw() element.core.DamageAll() } return true } func (element *TextBox) HandleDeselection () { element.selected = false if element.core.HasImage() { element.draw() element.core.DamageAll() } } func (element *TextBox) OnSelectionRequest (callback func () (granted bool)) { element.onSelectionRequest = callback } func (element *TextBox) OnSelectionMotionRequest ( callback func (direction tomo.SelectionDirection) (granted bool), ) { element.onSelectionMotionRequest = callback } func (element *TextBox) SetEnabled (enabled bool) { if element.enabled == enabled { return } element.enabled = enabled if element.core.HasImage () { element.draw() element.core.DamageAll() } } func (element *TextBox) SetPlaceholder (placeholder string) { if element.placeholder == placeholder { return } element.placeholder = placeholder element.placeholderDrawer.SetText([]rune(placeholder)) element.updateMinimumSize() if element.core.HasImage () { element.draw() element.core.DamageAll() } } func (element *TextBox) SetValue (text string) { // if element.text == text { return } element.text = []rune(text) element.runOnChange() element.valueDrawer.SetText(element.text) if element.cursor > element.valueDrawer.Length() { element.cursor = element.valueDrawer.Length() } element.scrollToCursor() if element.core.HasImage () { element.draw() element.core.DamageAll() } } func (element *TextBox) Value () (value string) { return string(element.text) } func (element *TextBox) Filled () (filled bool) { return len(element.text) > 0 } func (element *TextBox) OnKeyDown ( callback func (key tomo.Key, modifiers tomo.Modifiers) (handled bool), ) { element.onKeyDown = callback } func (element *TextBox) OnChange (callback func ()) { element.onChange = callback } // ScrollContentBounds returns the full content size of the element. func (element *TextBox) ScrollContentBounds () (bounds image.Rectangle) { bounds = element.valueDrawer.LayoutBounds() return bounds.Sub(bounds.Min) } // ScrollViewportBounds returns the size and position of the element's viewport // relative to ScrollBounds. func (element *TextBox) ScrollViewportBounds () (bounds image.Rectangle) { return image.Rect ( element.scroll, 0, element.scroll + element.scrollViewportWidth(), 0) } func (element *TextBox) scrollViewportWidth () (width int) { return element.Bounds().Inset(theme.Padding()).Dx() } // ScrollTo scrolls the viewport to the specified point relative to // ScrollBounds. func (element *TextBox) ScrollTo (position image.Point) { // constrain to minimum element.scroll = position.X if element.scroll < 0 { element.scroll = 0 } // constrain to maximum contentBounds := element.ScrollContentBounds() maxPosition := contentBounds.Max.X - element.scrollViewportWidth() if element.scroll > maxPosition { element.scroll = maxPosition } if element.core.HasImage () { element.draw() element.core.DamageAll() } if element.onScrollBoundsChange != nil { element.onScrollBoundsChange() } } // ScrollAxes returns the supported axes for scrolling. func (element *TextBox) ScrollAxes () (horizontal, vertical bool) { return true, false } func (element *TextBox) OnScrollBoundsChange (callback func ()) { element.onScrollBoundsChange = callback } func (element *TextBox) updateMinimumSize () { textBounds := element.placeholderDrawer.LayoutBounds() element.core.SetMinimumSize ( textBounds.Dx() + theme.Padding() * 2, element.placeholderDrawer.LineHeight().Round() + theme.Padding() * 2) } func (element *TextBox) runOnChange () { if element.onChange != nil { element.onChange() } } func (element *TextBox) scrollToCursor () { if !element.core.HasImage() { return } bounds := element.core.Bounds().Inset(theme.Padding()) bounds.Max.X -= element.valueDrawer.Em().Round() cursorPosition := element.valueDrawer.PositionOf(element.cursor) cursorPosition.X -= element.scroll maxX := bounds.Max.X minX := maxX if cursorPosition.X > maxX { element.scroll += cursorPosition.X - maxX } else if cursorPosition.X < minX { element.scroll -= minX - cursorPosition.X if element.scroll < 0 { element.scroll = 0 } } } func (element *TextBox) draw () { bounds := element.core.Bounds() artist.FillRectangle ( element.core, theme.InputPattern ( element.enabled, element.Selected()), bounds) if len(element.text) == 0 && !element.selected { // draw placeholder textBounds := element.placeholderDrawer.LayoutBounds() offset := image.Point { X: theme.Padding(), Y: theme.Padding(), } foreground := theme.ForegroundPattern(false) element.placeholderDrawer.Draw ( element.core, foreground, offset.Sub(textBounds.Min)) } else { // draw input value textBounds := element.valueDrawer.LayoutBounds() offset := image.Point { X: theme.Padding() - element.scroll, Y: theme.Padding(), } foreground := theme.ForegroundPattern(element.enabled) element.valueDrawer.Draw ( element.core, foreground, offset.Sub(textBounds.Min)) if element.selected { // cursor cursorPosition := element.valueDrawer.PositionOf ( element.cursor) artist.Line ( element.core, theme.ForegroundPattern(true), 1, cursorPosition.Add(offset), image.Pt ( cursorPosition.X, cursorPosition.Y + element.valueDrawer. LineHeight().Round()).Add(offset)) } } }