package theme

import (
	"io/fs"
	"strings"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"github.com/tamakyi/TamaBox/static"
)

// 主题必须自带的一套颜色令牌（形状/字体/阴影允许继承基础层）。
var requiredTokens = []string{
	"--tb-bg", "--tb-surface", "--tb-surface-2", "--tb-surface-hover", "--tb-border",
	"--tb-text", "--tb-text-secondary", "--tb-text-muted",
	"--tb-primary", "--tb-primary-weak",
}

func TestBuildAvailable(t *testing.T) {
	list, def, _ := build("sakura", "default, sakura ,bad_Slug,missing")

	assert.Equal(t, "sakura", def, "站点默认应取配置值")
	var slugs []string
	for _, item := range list {
		slugs = append(slugs, item.Slug)
	}
	// bad_Slug 非法、missing 没有 css 文件，都应被忽略
	assert.Equal(t, []string{"default", "sakura"}, slugs)
}

func TestBuildInvalidDefault(t *testing.T) {
	_, def, _ := build("does-not-exist", "sakura")
	assert.Equal(t, "", def, "默认主题不可用时回退基础外观")

	_, def, _ = build("default", "default,sakura")
	assert.Equal(t, "", def, "default 语义即基础外观，不应产生 css 请求")
}

func TestResolve(t *testing.T) {
	// 站点默认是 sakura
	themes, siteDef, index := build("sakura", "default,sakura")
	require.Equal(t, "sakura", siteDef)
	require.Contains(t, index, "sakura")
	require.NotEmpty(t, themes)

	assert.Equal(t, "sakura", resolve("", siteDef, index), "未选择时跟随站点默认")
	assert.Equal(t, "sakura", resolve("SAKURA", siteDef, index), "大小写不敏感")
	assert.Equal(t, "", resolve("default", siteDef, index), "显式选 default = 基础外观，不回退站点默认")
	assert.Equal(t, "sakura", resolve("nope", siteDef, index), "非法值回退站点默认")

	// 站点默认是基础外观
	_, def2, index2 := build("default", "default,sakura")
	assert.Equal(t, "", resolve("", def2, index2))
	assert.Equal(t, "sakura", resolve("sakura", def2, index2))
}

// TestThemeCSSComplete 防止「复制底稿只写了浅色块」这类问题：
// 半套主题不会报错，只会让深色模式变成浅色配色。
func TestThemeCSSComplete(t *testing.T) {
	entries, err := fs.ReadDir(static.FS, strings.TrimSuffix(themeCSSDir, "/"))
	require.NoError(t, err)
	require.NotEmpty(t, entries)

	for _, e := range entries {
		name := e.Name()
		if !strings.HasSuffix(name, ".css") {
			continue
		}
		slug := strings.TrimSuffix(name, ".css")
		// _scaffold.css 是给人复制的模板，default.css 永不加载（仅提供色块预览）
		if strings.HasPrefix(slug, "_") || slug == DefaultSlug {
			continue
		}

		raw, err := static.FS.ReadFile(themeCSSDir + name)
		require.NoError(t, err)
		css := string(raw)

		light := ruleBody(css, `html[data-theme-style="`+slug+`"]`)
		require.NotEmpty(t, light, "%s：缺少浅色块 html[data-theme-style=\"%s\"]", name, slug)

		dark := ruleBody(css, `html[data-theme="dark"][data-theme-style="`+slug+`"]`)
		require.NotEmpty(t, dark, "%s：缺少深色块 html[data-theme=\"dark\"][data-theme-style=\"%s\"]", name, slug)

		for _, tok := range requiredTokens {
			assert.NotEmpty(t, tokenValue(light, tok), "%s 浅色块缺少 %s", name, tok)
			assert.NotEmpty(t, tokenValue(dark, tok), "%s 深色块缺少 %s", name, tok)
		}
	}
}

func TestSwatch(t *testing.T) {
	raw, err := static.FS.ReadFile(themeCSSDir + "sakura.css")
	require.NoError(t, err)
	sw := swatchOf(string(raw), "sakura")
	assert.True(t, strings.HasPrefix(sw, "linear-gradient("), "swatch 应为渐变串，实际 %q", sw)
	assert.Contains(t, sw, "#e5678f")

	assert.Equal(t, "", swatchOf("/* 空文件 */", "sakura"), "取不到颜色时返回空串")
	assert.Equal(t, "", swatchOf(`html[data-theme-style="x"] { --tb-bg: url(evil); --tb-primary: #fff; }`, "x"),
		"非色值内容不得进入 swatch")
}

func TestRuleBodyIgnoresComments(t *testing.T) {
	// 令牌前面写一行注释很常见；不剥注释的话 tokenValue 会取到
	// "/* ... */ --tb-bg" 这种粘连键，色块预览静默失效。
	css := `html[data-theme-style="x"] {
    /* 磨砂卡片：半透明白 */
    --tb-bg: #ffffff;
    --tb-primary: rgba(74, 127, 193, 0.11);
}`
	body := ruleBody(css, `html[data-theme-style="x"]`)
	assert.Equal(t, "#ffffff", tokenValue(body, "--tb-bg"))
	assert.Equal(t, "rgba(74, 127, 193, 0.11)", tokenValue(body, "--tb-primary"))
}

// DisplayName 的回退是「自建主题零改代码」的前提：
// 生成器导出的主题只放一个 css，没人会为了名字去改四份词典。
// 一旦回退错，设置页会直接把 key 印出来（theme.name.test01），
// 用户看到的就是「主题名变成了键名」。
func TestDisplayName(t *testing.T) {
	// 已登记词条的仍走翻译
	assert.Equal(t, "基础外观", DisplayName("zh-CN", DefaultSlug))
	assert.Equal(t, "Shiroko", DisplayName("en", "shiroko"))

	// 没登记词条的自建主题：回退 slug，且绝不能返回 key 本身
	assert.Equal(t, "test01", DisplayName("zh-CN", "test01"))
	assert.Equal(t, "test01", DisplayName("ja", "test01"))
	assert.Equal(t, "my-theme", DisplayName("en", "my-theme"))
}