Document theme configuration

Author: aalmiray

README.adoc

@@ -97,6 +97,20 @@ Settings at the project root override those at your home directory. The format i
 [source,toml]
 .gm.toml
 ----
+[theme]
+# valid values are [none, dark, light, custom]
+name = "dark"
+# if name = custom then you must define the following 5 entries
+# color values follow https://github.com/gookit/color#use-a-256-color-style
+# color values must be between 0 and 255
+# first value is foreground
+# second value is background
+symbol = [125, 0]
+section = [47, 0]
+key = [130, 0]
+boolean = [200, 0]
+literal = [23, 0]
+
 [general]
 # same as passing -gq
 quiet = false

gum/config.go

@@ -329,26 +329,36 @@ func resolveSectionTheme(t *toml.Tree, config *Config) {
 		if v != nil {
 			data := v.([]interface{})
 			config.theme.symbol = [2]uint8{uint8(data[0].(int64)), uint8(data[1].(int64))}
+		} else {
+			config.theme.symbol = [2]uint8{125, 0}
 		}
 		v = table.Get("section")
 		if v != nil {
 			data := v.([]interface{})
 			config.theme.section = [2]uint8{uint8(data[0].(int64)), uint8(data[1].(int64))}
+		} else {
+			config.theme.symbol = [2]uint8{47, 0}
 		}
 		v = table.Get("key")
 		if v != nil {
 			data := v.([]interface{})
 			config.theme.key = [2]uint8{uint8(data[0].(int64)), uint8(data[1].(int64))}
+		} else {
+			config.theme.symbol = [2]uint8{130, 0}
 		}
 		v = table.Get("boolean")
 		if v != nil {
 			data := v.([]interface{})
 			config.theme.boolean = [2]uint8{uint8(data[0].(int64)), uint8(data[1].(int64))}
+		} else {
+			config.theme.symbol = [2]uint8{200, 0}
 		}
 		v = table.Get("literal")
 		if v != nil {
 			data := v.([]interface{})
 			config.theme.literal = [2]uint8{uint8(data[0].(int64)), uint8(data[1].(int64))}
+		} else {
+			config.theme.symbol = [2]uint8{23, 0}
 		}
 	}