Configuration values are now loaded from files

Stone will load from /etc/stone/stone.conf and ~/.config/stone/stone.conf

application.go

@@ -1,7 +1,6 @@
 package stone
 
 import "image"
-import "image/color"
 
 // Application represents an application.
 type Application struct {
@@ -25,29 +24,7 @@ func (application *Application) Run () (
 	if height < 1 { height = 20 }
 	application.DamageBuffer.SetSize(width, height)
 
-	// TODO: load these from a file
+	application.config.load()
-	application.config.colors = [8]color.Color {
-		// background
-		color.RGBA { R: 0, G: 0, B: 0, A: 0 },
-		// foreground
-		color.RGBA { R: 0xFF, G: 0xFF, B: 0xFF, A: 0xFF },
-		// red
-		color.RGBA { R: 0xFF, G: 0x00, B: 0x00, A: 0xFF },
-		// orange
-		color.RGBA { R: 0xFF, G: 0x80, B: 0x00, A: 0xFF },
-		// yellow
-		color.RGBA { R: 0xFF, G: 0xFF, B: 0x00, A: 0xFF },
-		// green
-		color.RGBA { R: 0x00, G: 0xFF, B: 0x00, A: 0xFF },
-		// blue
-		color.RGBA { R: 0x00, G: 0x00, B: 0xFF, A: 0xFF },
-		// purple
-		color.RGBA { R: 0x80, G: 0x00, B: 0xFF, A: 0xFF },
-	}
-	application.config.fontName = ""
-	application.config.fontSize = 11
-	
-	application.config.padding = 2
 
 	application.backend, err = instantiateBackend(application)
 	if err != nil { return }

config.go

@@ -1,6 +1,11 @@
 package stone
 
+import "os"
+import "bufio"
+import "strings"
+import "strconv"
 import "image/color"
+import "path/filepath"
 
 // Config stores configuration parameters. Backends only should honor parameters
 // that they can support.
@@ -35,3 +40,117 @@ func (config *Config) FontName () (fontName string) {
 	fontName = config.fontName
 	return
 }
+
+func (config *Config) load () {
+	// TODO: load these from a file
+	config.colors = [8]color.Color {
+		// background
+		color.RGBA { R: 0, G: 0, B: 0, A: 0 },
+		// foreground
+		color.RGBA { R: 0xFF, G: 0xFF, B: 0xFF, A: 0xFF },
+		// red
+		color.RGBA { R: 0xFF, G: 0x00, B: 0x00, A: 0xFF },
+		// orange
+		color.RGBA { R: 0xFF, G: 0x80, B: 0x00, A: 0xFF },
+		// yellow
+		color.RGBA { R: 0xFF, G: 0xFF, B: 0x00, A: 0xFF },
+		// green
+		color.RGBA { R: 0x00, G: 0xFF, B: 0x00, A: 0xFF },
+		// blue
+		color.RGBA { R: 0x00, G: 0x00, B: 0xFF, A: 0xFF },
+		// purple
+		color.RGBA { R: 0x80, G: 0x00, B: 0xFF, A: 0xFF },
+	}
+	config.fontName = ""
+	config.fontSize = 11
+	config.padding = 2
+
+	config.loadFile("/etc/stone/stone.conf")
+	homeDirectory, err := os.UserHomeDir()
+	if err != nil { return }
+	config.loadFile(filepath.Join(homeDirectory, "/.config/stone/stone.conf"))
+	
+	return
+}
+
+func (config *Config) loadFile (path string) {
+	file, err := os.Open(path)
+	if err != nil { return }
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+		
+		if len(line) == 0 {
+			continue
+		}
+
+		if line[0] == '#' {
+			continue
+		}
+	
+		key, value, found := strings.Cut(scanner.Text(), ":")
+		if !found {
+			println (
+				"config: error in file", path +
+				": key-value separator missing")
+			println(scanner.Text())
+			continue
+		}
+		key   = strings.TrimSpace(key)
+		value = strings.TrimSpace(value)
+		var valueInt int
+		var valueColor color.Color
+
+		if value[0] == '#' {
+			if len(value) != 7  {
+				println (
+					"config: error in file", path +
+					": malformed color literal")
+				continue
+			}
+
+			colorInt, err := strconv.ParseUint(value[1:7], 16, 24)
+			if err != nil  {
+				println (
+					"config: error in file", path +
+					": malformed color literal")
+				continue
+			}
+
+			valueColor = color.RGBA {
+				R: uint8(colorInt >> 16),
+				G: uint8(colorInt >> 8),
+				B: uint8(colorInt),
+				A: 0xFF,
+			}
+		} else {
+			valueInt, _ = strconv.Atoi(value)
+		}
+
+		switch key {
+		case "fontNormal":
+			config.fontName = value
+		case "fontSize":
+			config.fontSize = valueInt
+		case "padding":
+			config.padding = valueInt
+		case "colorBackground":
+			config.colors[ColorBackground] = valueColor
+		case "colorForeground":
+			config.colors[ColorForeground] = valueColor
+		case "colorRed":
+			config.colors[ColorRed] = valueColor
+		case "colorOrange":
+			config.colors[ColorOrange] = valueColor
+		case "colorYellow":
+			config.colors[ColorYellow] = valueColor
+		case "colorGreen":
+			config.colors[ColorGreen] = valueColor
+		case "colorBlue":
+			config.colors[ColorBlue] = valueColor
+		case "colorPurple":
+			config.colors[ColorPurple] = valueColor
+		}
+	}
+}