use Term
	Color

use Highlight
	HighlightType

Colors
	fg   Color
	bg   Color

HighlightColors
	type HighlightType
	fg   Color
	bg   Maybe Color

fn hlt (type HighlightType, fg Color): HighlightColors { type, fg, bg: None }

Theme
	default     Colors

	cursor      Colors
	selection   Colors
	line-num    Colors
	line-num-hl Colors
	overlay     Colors

	highlights  Slice HighlightColors


# I think a proper theme helps an editor a lot. I want to capture the general vibe of the thing.
fn rgb (x): Term.ColorRGB(Term.rgb-from-hex(x))
camel        = rgb(0xb38a58)
olive        = rgb(0x6F732F)
tea-green    = rgb(0xe2f9b8)
chocolate    = rgb(0xd16014)
muted-olive  = rgb(0xbbce8a)
palm-leaf    = rgb(0x939f5c)

lime-green   = rgb(0x31cb00)
forest-green = rgb(0x119822)
green        = rgb(0x2a7221)
dark-spruce  = rgb(0x1e441e)
evergreen    = rgb(0x152614)

# basically, i was going for a minecraft tundra-esque look, but what came out of it looks more like goblin-ultra.
goblin-ultra =& Theme
	{ default: { bg: evergreen, fg: lime-green }

	, cursor: { bg: lime-green, fg: evergreen }
	, selection: { bg: forest-green, fg: evergreen }
	, line-num: { bg: evergreen, fg: forest-green }
	, line-num-hl: { bg: evergreen, fg: tea-green }
	, overlay: { bg: dark-spruce, fg: lime-green }
	, highlights: Array.as-slice(&
		[ hlt(Highlight.Number, green)
		, hlt(Highlight.String, camel)
		, hlt(Highlight.Comment, dark-spruce)

		, hlt(Highlight.Ident1, lime-green)
		, hlt(Highlight.Ident2, muted-olive)
		, hlt(Highlight.Ident3, tea-green)
		, hlt(Highlight.Ident4, palm-leaf)

		, hlt(Highlight.Keyword1, tea-green)
		, hlt(Highlight.Keyword2, chocolate)

		, hlt(Highlight.Special1, olive)
		, hlt(Highlight.Special2, forest-green)
		, hlt(Highlight.Special3, camel)

		, { type: Highlight.Invalid, fg: evergreen, bg: Just(Term.Color8(Term.Red8)) }
		])
	}


dark-theme =& Theme
	{ default: { bg: Term.Color8(Term.Black8), fg: Term.Color8(Term.White8) }

	, cursor: { bg: Term.Color8(Term.White8), fg: Term.Color8(Term.Black8) }
	, selection: { bg: Term.Color16(Term.BrightWhite16), fg: Term.Color16(Term.Black16) }
	, line-num: { bg: Term.Color8(Term.Black8), fg: Term.Color8(Term.White8) }
	, line-num-hl: { bg: Term.Color8(Term.White8), fg: Term.Color8(Term.Black8) }
	, overlay: { bg: Term.Color8(Term.White8), fg: Term.Color8(Term.Black8) }
	, highlights: Slice.empty()
	}

light-theme =& Theme
	{ default: { bg: Term.Color16(Term.BrightWhite16), fg: Term.Color8(Term.Black8) }

	, cursor: { bg: Term.Color8(Term.Black8), fg: Term.Color16(Term.BrightWhite16) }
	, selection: { bg: Term.Color16(Term.White16), fg: Term.Color16(Term.BrightWhite16) }
	, line-num: { bg: Term.Color16(Term.BrightWhite16), fg: Term.Color8(Term.Black8) }
	, line-num-hl: { bg: Term.Color8(Term.Black8), fg: Term.Color16(Term.BrightWhite16) }
	, overlay: { bg: Term.Color8(Term.Black8), fg: Term.Color16(Term.BrightWhite16) }
	, highlights: Slice.empty()
	}


default = goblin-ultra
all-themes = Array.as-slice(&
	[ ('default', default)
	, ('goblin-ultra', goblin-ultra)
	, ('dark-mono', dark-theme)
	, ('light-mono', light-theme)
	])

# partially match theme
fn match-theme (name StrView) -> Maybe (Ptr Theme)
	if name null()  # empty strings should not match bruh.
		return None

	return all-themes
		filter(fn ((theme-name, theme)): theme-name Str.begins-with(name))
		map(snd)
		head()


fn find-colors-for-highlight (theme Ptr Theme, hltype HighlightType) -> Colors:
	theme&.highlights
	filter(fn hlc: hlc.type == hltype)
	head()
	Misc.maybe
		( fn hlc: { fg: hlc.fg, bg: hlc.bg or-else(theme&.default.bg) }
		# , { fg: theme&.default.fg, bg: Term.Color8(Term.Red8) }  # error colors for exhaustiveness checking.
		, theme&.default
		)