package main

import (
	"bytes"
	"embed"
	"flag"
	"fmt"
	"html/template"
	"io/fs"
	"log"
	"net/http"
	"os"
	"sort"
	"strconv"
	"toolbox/pkg/base"
	_ "toolbox/pkg/learnnumber"
	_ "toolbox/pkg/zitie" // 匿名导入以触发 init()

	"github.com/gin-gonic/gin"
)

//go:embed web/*
var webFS embed.FS

func main() {
	portFlag := flag.Int("port", 0, "端口号 (优先于环境变量 PORT)")
	gaFlag := flag.String("ga", "", "Google Analytics ID")
	flag.Parse()

	gaID := *gaFlag
	if gaID == "" {
		gaID = os.Getenv("GA_ID")
	}

	if os.Getenv("GIN_MODE") == "release" {
		gin.SetMode(gin.ReleaseMode)
	}

	r := gin.New()
	r.Use(gin.Logger(), gin.Recovery())
	r.RedirectTrailingSlash = false
	r.RedirectFixedPath = false
	_ = r.SetTrustedProxies(nil)

	// 1. 自动发现并注册工具路由
	api := r.Group("/api")
	{
		for id, tool := range base.Registry {
			if err := tool.Init(); err != nil {
				log.Fatalf("Failed to initialize tool %s: %v", id, err)
			}
			tool.RegisterRoutes(api.Group("/" + id))
		}
	}

	// 2. 静态资源
	subFS, _ := fs.Sub(webFS, "web")
	r.StaticFS("/static", http.FS(subFS))

	// 2.5 SEO 静态文件映射
	r.GET("/robots.txt", func(c *gin.Context) {
		c.String(http.StatusOK, "User-agent: *\nAllow: /\nSitemap: https://toolbox.pengzhan.dev/sitemap.xml\n")
	})
	r.GET("/sitemap.xml", func(c *gin.Context) {
		var buf bytes.Buffer
		buf.WriteString("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n")
		buf.WriteString("<urlset xmlns=\"http://www.sitemaps.org/schemas/sitemap/0.9\">\n")
		buf.WriteString("  <url><loc>https://toolbox.pengzhan.dev/</loc><priority>1.0</priority></url>\n")

		// 动态根据注册的工具生成路由
		for id := range base.Registry {
			fmt.Fprintf(&buf, "  <url><loc>https://toolbox.pengzhan.dev/%s</loc><priority>0.8</priority></url>\n", id)
		}
		buf.WriteString("</urlset>")
		c.Data(http.StatusOK, "application/xml; charset=utf-8", buf.Bytes())
	})
	// 3. 模板引擎初始化
	// 递归加载 web 目录下所有的 .html 文件
	tmpl, err := template.ParseFS(subFS, "layout.html", "index.html", "tools/*.html")
	if err != nil {
		log.Fatalf("Failed to parse templates: %v", err)
	}

	// 通用页面渲染函数
	serveIndex := func(c *gin.Context) {
		path := c.Request.URL.Path
		title := "探索工具箱"
		desc := "基于 Go 语言构建的模块化个人工具箱，提供汉字字帖生成、数字学习等多种实用生产力工具。"
		keywords := "个人工具箱, 汉字字帖生成, 书法练习, 数字学习, Own-Tools"
		baseURL := "https://toolbox.pengzhan.dev"
		canonical := baseURL + path
		                // 针对不同路径设置 SEO 标签
		                switch path {
		                case "/zitie":
		                        title = "汉字字帖生成器 - 教学方格与步进式分解"
		                        desc = "在线生成 2x3 教学方格字帖和 9 列步进式笔顺分解字帖，支持多种书法字体和古风排版。"
		                        keywords = "字帖生成, 笔顺分解, 汉字教学, 书法字帖, 练字"
		                case "/learn-number":
		                        title = "趣味数字学习工具"
		                        desc = "为儿童设计的数字学习与计数练习工具，生动活泼，寓教于乐。"
		                        keywords = "数字学习, 儿童计数, 幼小衔接"
		                }
		
		data := gin.H{
			"Title":        title,
			"Description":  desc,
			"Keywords":     keywords,
			"CanonicalURL": canonical,
			"GA_ID":        gaID,
		}

		var buf bytes.Buffer
		// 因为已经 Sub 了，模板名就是文件名
		if err := tmpl.ExecuteTemplate(&buf, "layout.html", data); err != nil {
			c.String(http.StatusInternalServerError, "Template error: %v", err)
			return
		}
		c.Data(http.StatusOK, "text/html; charset=utf-8", buf.Bytes())
	}
	r.GET("/", serveIndex)
	r.GET("/api/tools", func(c *gin.Context) {
		var list []map[string]string
		ids := make([]string, 0, len(base.Registry))
		for id := range base.Registry {
			ids = append(ids, id)
		}
		sort.Strings(ids)

		for _, id := range ids {
			t := base.Registry[id]
			list = append(list, map[string]string{
				"id":    t.ID(),
				"name":  t.Name(),
				"desc":  t.Description(),
				"emoji": t.Emoji(),
			})
		}
		c.JSON(http.StatusOK, list)
	})

	// 4. 全路径回退 (SPA Routing)
	r.NoRoute(serveIndex)

	// 5. 启动
	var finalPort string
	if *portFlag > 0 {
		finalPort = strconv.Itoa(*portFlag)
	} else if envPort := os.Getenv("PORT"); envPort != "" {
		finalPort = envPort
	} else {
		finalPort = "8080"
	}

	log.Printf("Toolbox server starting on :%s", finalPort)
	if err := r.Run(":" + finalPort); err != nil {
		log.Fatalf("Server failed: %v", err)
	}
}