package app

import (
	"fmt"
	"net/http"
	"net/url"

	"github.com/go-chi/chi/v5"
	"github.com/go-chi/chi/v5/middleware"
	"github.com/samber/lo"
	"github.com/spf13/viper"
	"go.fifitido.net/ytdl-web/pkg/httpx"
	"go.fifitido.net/ytdl-web/pkg/view"
	"go.fifitido.net/ytdl-web/version"
	"go.fifitido.net/ytdl-web/ytdl"
	"go.fifitido.net/ytdl-web/ytdl/metadata"
	"golang.org/x/exp/slog"
)

func Router(ytdl ytdl.Ytdl) http.Handler {
	r := chi.NewRouter()

	r.Use(middleware.RequestID)
	r.Use(middleware.RealIP)
	r.Use(middleware.Logger)
	r.Use(middleware.Recoverer)

	r.Get("/", indexHandler(ytdl))
	r.Get("/home", homeIndex)

	r.Route("/download", func(r chi.Router) {
		r.Get("/", listDownloads(ytdl))
		r.Head("/proxy", proxyDownload(ytdl))
		r.Get("/proxy", proxyDownload(ytdl))
	})

	return r
}

func indexHandler(ytdl ytdl.Ytdl) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		views.Render(w, "index", view.Data{
			"BasePath":      viper.GetString("base_path"),
			"Version":       version.Version,
			"Build":         version.Build,
			"BinaryVersion": ytdl.Version(),
		}, "layouts/main")
	}
}

func homeIndex(w http.ResponseWriter, r *http.Request) {
	views.Render(w, "index", view.Data{
		"BasePath": viper.GetString("base_path"),
	})
}

func listDownloads(ytdl ytdl.Ytdl) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		urlBytes, err := url.QueryUnescape(r.URL.Query()["url"][0])
		if err != nil {
			views.Render(w, "index", view.Data{
				"BasePath": viper.GetString("base_path"),
				"Error": view.Data{
					"Message": "Invalid URL",
				},
			})
			return
		}
		url := string(urlBytes)
		if len(url) < 1 {
			views.Render(w, "index", view.Data{
				"BasePath": viper.GetString("base_path"),
				"Error": view.Data{
					"Message": "Invalid URL",
				},
			})
			return
		}

		meta, err := ytdl.GetMetadata(url)
		if err != nil {
			views.Render(w, "index", view.Data{
				"BasePath": viper.GetString("base_path"),
				"Error": view.Data{
					"Message": "Could not find a video at that url, maybe try again?",
				},
			})
			return
		}

		views.Render(w, "download", view.Data{
			"BasePath": viper.GetString("base_path"),
			"Url":      url,
			"Meta":     meta,
			"Videos":   GetVideos(meta),
		})
	}
}

func proxyDownload(ytdl ytdl.Ytdl) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		rawUrl, err := httpx.Query(r, "url")
		if err != nil {
			http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
			return
		}

		urlBytes, err := url.QueryUnescape(rawUrl)
		if err != nil {
			slog.Error("Failed to decode url param", slog.String("error", err.Error()))
			http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
			return
		}
		url := string(urlBytes)
		if len(url) < 1 {
			http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
			return
		}

		formatId, err := httpx.Query(r, "format")
		if err != nil {
			http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
			return
		}

		meta, err := ytdl.GetMetadata(url)
		if err != nil {
			slog.Error("Failed to get metadata", slog.String("error", err.Error()))
			http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
			return
		}
		videos := GetVideos(meta)

		index, err := httpx.QueryInt(r, "index")
		if err != nil || index < 0 || index >= len(videos) {
			http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
			return
		}

		video := videos[index]
		format, ok := lo.Find(video.Formats, func(format metadata.Format) bool {
			return format.FormatID == formatId
		})
		if !ok {
			http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
			return
		}

		w.Header().Set("Content-Disposition", fmt.Sprintf("attachment; filename=\"%s-%s.%s\"", meta.ID, format.Resolution, format.Ext))
		if format.Filesize != nil {
			w.Header().Set("Content-Length", fmt.Sprint(*format.Filesize))
		} else if format.FilesizeApprox != nil {
			w.Header().Set("Content-Length", fmt.Sprint(*format.FilesizeApprox))
		}

		if len(videos) == 1 {
			index = -1
		}

		if err := ytdl.Download(w, url, format.FormatID, index); err != nil {
			slog.Error("Failed to download", slog.String("error", err.Error()))
			http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
			return
		}
	}
}