package ui

import (
	"image/color"
	"testing"

	"github.com/gdamore/tcell/v2"
	"github.com/rivo/tview"
)

func TestParseTerminalAnswers(t *testing.T) {
	for _, tc := range []struct {
		name     string
		got      string
		graphics bool
		bg       color.RGBA
		hasBG    bool
	}{
		{"ghostty", "\x1b_Gi=31;OK\x1b\\\x1b]11;rgb:1e1e/1e1e/2e2e\x1b\\\x1b[?62;22c", true, color.RGBA{30, 30, 46, 255}, true},
		{"text color too", "\x1b]10;rgb:4c4c/4f4f/6969\x1b\\\x1b]11;rgb:efef/f1f1/f5f5\x1b\\\x1b[?62c", false, color.RGBA{239, 241, 245, 255}, true},
		{"bel and two digits", "\x1b]11;rgb:ff/80/00\a\x1b[?1;2c", false, color.RGBA{255, 128, 0, 255}, true},
		{"one digit", "\x1b]11;rgb:f/0/8\x1b\\\x1b[?6c", false, color.RGBA{255, 0, 136, 255}, true},
		{"only device attributes", "\x1b[?1;2c", false, color.RGBA{}, false},
		{"garbage", "\x1b]11;rgb:zz/00/00\x1b\\\x1b[?6c", false, color.RGBA{}, false},
		{"nothing", "", false, color.RGBA{}, false},
	} {
		info := parseTerminalAnswers([]byte(tc.got))
		if info.graphics != tc.graphics || info.hasBG != tc.hasBG || info.bg != tc.bg {
			t.Errorf("%s: %+v", tc.name, info)
		}
	}
}

func TestChooseTheme(t *testing.T) {
	dark := terminalInfo{bg: color.RGBA{30, 30, 46, 255}, hasBG: true}
	light := terminalInfo{bg: color.RGBA{239, 241, 245, 255}, hasBG: true}
	for _, tc := range []struct {
		setting string
		info    terminalInfo
		want    string
	}{
		{"", light, "light"},
		{"auto", dark, "dark"},
		{"auto", terminalInfo{}, "dark"},
		{"dark", light, "dark"},
		{"light", dark, "light"},
	} {
		if th, note := chooseTheme(tc.setting, tc.info); th.name != tc.want {
			t.Errorf("%q with %+v: %s (%s)", tc.setting, tc.info, th.name, note)
		}
	}
}

func TestThemeApply(t *testing.T) {
	oldStyles, oldCurrent := tview.Styles, current
	oldNames := map[string]tcell.Color{}
	for k, v := range tcell.ColorNames {
		oldNames[k] = v
	}
	defer func() {
		tview.Styles, current = oldStyles, oldCurrent
		for k, v := range oldNames {
			tcell.ColorNames[k] = v
		}
	}()

	lightTheme.apply()
	if tview.Styles.PrimitiveBackgroundColor != lightTheme.bg || tview.Styles.PrimaryTextColor != lightTheme.text {
		t.Error("tview styles not set")
	}
	// Color names in texts mean the theme's colors.
	if named("yellow") != lightTheme.yellow || tcell.GetColor("black") != lightTheme.bg || tcell.GetColor("white") != lightTheme.text {
		t.Error("color names not set")
	}
	if current.name != "light" {
		t.Error("current theme not set")
	}
}

func TestThemeColorsSurvive256Colors(t *testing.T) {
	// Every theme color is its own nearest match in the 256-color palette, so
	// a terminal without 24-bit color shows it exactly and never picks one of
	// the first 16 colors, which color themes change.
	palette := make([]tcell.Color, 256)
	for i := range palette {
		palette[i] = tcell.PaletteColor(i)
	}
	for _, th := range []theme{darkTheme, lightTheme} {
		for _, c := range []tcell.Color{th.bg, th.text, th.border, th.field, th.fieldMuted, th.list, th.pressed, th.toast,
			th.gray, th.yellow, th.green, th.red, th.blue, th.purple} {
			if got := tcell.FindColor(c, palette); got < tcell.PaletteColor(16) {
				t.Errorf("%s theme: %v maps to palette color %d", th.name, c, got-tcell.ColorValid)
			}
		}
	}
}