package router

import (
	"embed"
	"net/http"
	"strings"

	"github.com/QuantumNous/new-api/common"
	"github.com/QuantumNous/new-api/controller"
	"github.com/QuantumNous/new-api/middleware"
	"github.com/gin-contrib/gzip"
	"github.com/gin-contrib/static"
	"github.com/gin-gonic/gin"
)

// ThemeAssets holds the embedded frontend assets for both themes and
// the image-gen sub-app.
type ThemeAssets struct {
	DefaultBuildFS   embed.FS
	DefaultIndexPage []byte
	ClassicBuildFS   embed.FS
	ClassicIndexPage []byte
	// ImageGen is the image-generation sub-app, served at /image-gen/.
	// It shares the same origin as the rest of new-api so /api/* and /v1/*
	// are reachable via the new-api session cookie (no CORS, no sk-key).
	ImageGenBuildFS   embed.FS
	ImageGenIndexPage []byte
}

func SetWebRouter(router *gin.Engine, assets ThemeAssets) {
	defaultFS := common.EmbedFolder(assets.DefaultBuildFS, "web/default/dist")
	classicFS := common.EmbedFolder(assets.ClassicBuildFS, "web/classic/dist")
	themeFS := common.NewThemeAwareFS(defaultFS, classicFS)

	// image-gen sub-app: serve static files under /image-gen, fall back to
	// its index.html for unknown sub-paths (SPA).
	imageGenFS := common.EmbedFolder(assets.ImageGenBuildFS, "web/image-gen/dist")

	router.Use(gzip.Gzip(gzip.DefaultCompression))
	router.Use(middleware.GlobalWebRateLimit())
	router.Use(middleware.Cache())
	router.Use(static.Serve("/image-gen", imageGenFS))
	router.Use(static.Serve("/", themeFS))
	router.NoRoute(func(c *gin.Context) {
		c.Set(middleware.RouteTagKey, "web")
		uri := c.Request.RequestURI
		// API/relay/static paths are handled by their own routers — 404 cleanly.
		if strings.HasPrefix(uri, "/v1") || strings.HasPrefix(uri, "/api") || strings.HasPrefix(uri, "/assets") {
			controller.RelayNotFound(c)
			return
		}
		c.Header("Cache-Control", "no-cache")
		switch {
		case strings.HasPrefix(uri, "/image-gen"):
			// SPA fallback for the image-gen sub-app: any sub-path that didn't
			// hit a static file gets the image-gen index.html.
			c.Data(http.StatusOK, "text/html; charset=utf-8", assets.ImageGenIndexPage)
		case common.GetTheme() == "classic":
			c.Data(http.StatusOK, "text/html; charset=utf-8", assets.ClassicIndexPage)
		default:
			c.Data(http.StatusOK, "text/html; charset=utf-8", assets.DefaultIndexPage)
		}
	})
}