package web

import (
	"net/http"
	"strconv"
	"strings"

	"git.noroutes.net/NoRoutes/vibetunes/internal/auth"
	"git.noroutes.net/NoRoutes/vibetunes/internal/database"
)

const pageSize = 60

func (h *Web) handleHome(w http.ResponseWriter, r *http.Request) {
	user := auth.UserFromContext(r.Context())

	albums, err := database.ListAlbums(h.DB, 12, 0)
	if err != nil {
		http.Error(w, "internal error", http.StatusInternalServerError)
		return
	}
	var recentlyAdded []AlbumView
	for _, a := range albums {
		recentlyAdded = append(recentlyAdded, toAlbumView(h.DB, a))
	}

	var recentlyPlayedAlbums []AlbumView
	if user != nil {
		history, err := database.ListRecentlyPlayed(h.DB, user.ID, 30)
		if err == nil {
			seen := map[string]bool{}
			for _, entry := range history {
				song, err := database.GetSong(h.DB, entry.SongID)
				if err != nil || !song.AlbumID.Valid || seen[song.AlbumID.String] {
					continue
				}
				seen[song.AlbumID.String] = true
				album, err := database.GetAlbum(h.DB, song.AlbumID.String)
				if err != nil {
					continue
				}
				recentlyPlayedAlbums = append(recentlyPlayedAlbums, toAlbumView(h.DB, album))
				if len(recentlyPlayedAlbums) >= 12 {
					break
				}
			}
		}
	}

	hasLibrary := len(recentlyAdded) > 0
	h.page(w, r, "home", "home", "Home", struct {
		HasLibrary           bool
		RecentlyAdded        []AlbumView
		RecentlyPlayedAlbums []AlbumView
	}{hasLibrary, recentlyAdded, recentlyPlayedAlbums})
}

func (h *Web) handleArtists(w http.ResponseWriter, r *http.Request) {
	artists, err := database.ListArtists(h.DB)
	if err != nil {
		http.Error(w, "internal error", http.StatusInternalServerError)
		return
	}
	var views []ArtistView
	for _, a := range artists {
		views = append(views, toArtistView(a))
	}
	h.page(w, r, "artists", "artists", "Artists", views)
}

func (h *Web) handleArtist(w http.ResponseWriter, r *http.Request) {
	id := r.PathValue("id")
	artist, err := database.GetArtist(h.DB, id)
	if err != nil {
		http.NotFound(w, r)
		return
	}
	albums, err := database.ListAlbumsByArtist(h.DB, id)
	if err != nil {
		http.Error(w, "internal error", http.StatusInternalServerError)
		return
	}
	var views []AlbumView
	for _, a := range albums {
		views = append(views, toAlbumView(h.DB, a))
	}
	h.page(w, r, "artist", "artists", artist.Name, struct {
		Artist *database.Artist
		Albums []AlbumView
	}{artist, views})
}

func (h *Web) handleAlbums(w http.ResponseWriter, r *http.Request) {
	offset := parseOffset(r)
	albums, err := database.ListAlbums(h.DB, pageSize+1, offset)
	if err != nil {
		http.Error(w, "internal error", http.StatusInternalServerError)
		return
	}
	hasMore := len(albums) > pageSize
	if hasMore {
		albums = albums[:pageSize]
	}
	var views []AlbumView
	for _, a := range albums {
		views = append(views, toAlbumView(h.DB, a))
	}
	h.page(w, r, "albums", "albums", "Albums", struct {
		Albums     []AlbumView
		HasMore    bool
		NextOffset int
	}{views, hasMore, offset + pageSize})
}

func (h *Web) handleAlbum(w http.ResponseWriter, r *http.Request) {
	user := auth.UserFromContext(r.Context())
	id := r.PathValue("id")
	album, err := database.GetAlbum(h.DB, id)
	if err != nil {
		http.NotFound(w, r)
		return
	}
	songs, err := database.ListSongsByAlbum(h.DB, id)
	if err != nil {
		http.Error(w, "internal error", http.StatusInternalServerError)
		return
	}
	userID := ""
	if user != nil {
		userID = user.ID
	}
	var rows []SongRow
	for _, s := range songs {
		rows = append(rows, toSongRow(h.DB, s, album, userID))
	}
	starred := false
	if user != nil {
		starred, _ = database.IsStarred(h.DB, user.ID, "album", album.ID)
	}
	h.page(w, r, "album", "albums", album.Title, struct {
		Album   AlbumView
		Songs   []SongRow
		Starred bool
	}{toAlbumView(h.DB, album), rows, starred})
}

func (h *Web) handleSongs(w http.ResponseWriter, r *http.Request) {
	user := auth.UserFromContext(r.Context())
	offset := parseOffset(r)
	songs, err := database.ListSongs(h.DB, pageSize+1, offset)
	if err != nil {
		http.Error(w, "internal error", http.StatusInternalServerError)
		return
	}
	hasMore := len(songs) > pageSize
	if hasMore {
		songs = songs[:pageSize]
	}
	userID := ""
	if user != nil {
		userID = user.ID
	}
	var rows []SongRow
	for _, s := range songs {
		rows = append(rows, toSongRow(h.DB, s, albumOf(h.DB, s), userID))
	}
	h.page(w, r, "songs", "songs", "Songs", struct {
		Songs      []SongRow
		HasMore    bool
		NextOffset int
	}{rows, hasMore, offset + pageSize})
}

func (h *Web) handleGenres(w http.ResponseWriter, r *http.Request) {
	genres, err := database.ListGenres(h.DB)
	if err != nil {
		http.Error(w, "internal error", http.StatusInternalServerError)
		return
	}
	h.page(w, r, "genres", "genres", "Genres", genres)
}

func (h *Web) handleSearch(w http.ResponseWriter, r *http.Request) {
	user := auth.UserFromContext(r.Context())
	query := strings.TrimSpace(r.URL.Query().Get("q"))

	var artistViews []ArtistView
	var albumViews []AlbumView
	var songRows []SongRow

	if query != "" {
		like := "%" + query + "%"

		artistRows, _ := h.DB.Query(`SELECT DISTINCT a.id, a.name FROM artists a JOIN album_artists aa ON aa.artist_id = a.id WHERE a.name LIKE ? ORDER BY a.name LIMIT 20`, like)
		if artistRows != nil {
			defer artistRows.Close()
			for artistRows.Next() {
				var id, name string
				if artistRows.Scan(&id, &name) == nil {
					artistViews = append(artistViews, ArtistView{ID: id, Name: name})
				}
			}
		}

		albumRows, _ := h.DB.Query(`SELECT id FROM albums WHERE title LIKE ? ORDER BY title LIMIT 20`, like)
		if albumRows != nil {
			defer albumRows.Close()
			for albumRows.Next() {
				var id string
				if albumRows.Scan(&id) == nil {
					if album, err := database.GetAlbum(h.DB, id); err == nil {
						albumViews = append(albumViews, toAlbumView(h.DB, album))
					}
				}
			}
		}

		songIDRows, _ := h.DB.Query(`SELECT id FROM songs WHERE title LIKE ? ORDER BY title LIMIT 40`, like)
		if songIDRows != nil {
			defer songIDRows.Close()
			userID := ""
			if user != nil {
				userID = user.ID
			}
			for songIDRows.Next() {
				var id string
				if songIDRows.Scan(&id) == nil {
					if song, err := database.GetSong(h.DB, id); err == nil {
						songRows = append(songRows, toSongRow(h.DB, song, albumOf(h.DB, song), userID))
					}
				}
			}
		}
	}

	h.page(w, r, "search", "search", "Search", struct {
		Query   string
		Artists []ArtistView
		Albums  []AlbumView
		Songs   []SongRow
	}{query, artistViews, albumViews, songRows})
}

func parseOffset(r *http.Request) int {
	n, err := strconv.Atoi(r.URL.Query().Get("offset"))
	if err != nil || n < 0 {
		return 0
	}
	return n
}