const std = @import("std");
const jetzig = @import("jetzig");
const jetquery = @import("jetzig").jetquery;
const Scrobble = @import("../../types.zig").LastFMScrobble;
const lastfm = @import("../../types.zig").LastFM;

// The `run` function for a job is invoked every time the job is processed by a queue worker
// (or by the Jetzig server if the job is processed in-line).
//
// Arguments:
// * allocator: Arena allocator for use during the job execution process.
// * params:    Params assigned to a job (from a request, values added to response data).
// * env:       Provides the following fields:
//              - logger:      Logger attached to the same stream as the Jetzig server.
//              - environment: Enum of `{ production, development }`.
pub fn run(allocator: std.mem.Allocator, params: *jetzig.data.Value, env: jetzig.jobs.JobEnv) !void {
    _ = allocator;

    if (params.getT(.array, "scrobbles")) |scrobbles| {
        for (scrobbles.items()) |item| {
            const scrobble: Scrobble = .{ .track = item.track.?, .artist = item.artist.?, .album = item.album.?, .date = item.date.? };

            // Make hashes
            const album_hash = std.hash.Fnv1a_64.hash(scrobble.album);
            const artist_hash = std.hash.Fnv1a_64.hash(scrobble.artist);
            const song_hash = std.hash.Fnv1a_64.hash(scrobble.track);

            // Make IDs
            // Song:    Song hash XOR artist hash XOR album hash
            //          This way, if two songs share a name, then
            //          the IDs also depend on the hash of the album
            //          they're on, as well as the artist name. As far
            //          as I can tell, this is only as issue for Sufjan
            //          Steven's `Songs for Christmas`.

            // Album:   If the album is not self-titled, then
            //          album hash XOR artist hash. This way, if two
            //          artists have an album of the same name, then
            //          the IDs also depend on the hash of the artist
            //          name. As far as I can tell, this is only an
            //          issue for Weezer.

            // Artist   Artist hash. If two artists have the same name,
            //          then a descriptive string can be provided to
            //          differentiate after the fact, or in a rule.
            var album_id: u64 = 0;
            const song_id = (song_hash ^ artist_hash ^ album_hash);
            if (artist_hash == album_hash) {
                album_id = album_hash;
            } else {
                album_id = (artist_hash ^ album_hash);
            }
            const artist_id = artist_hash;

            const artistalbum_offset = try jetzig.database.Query(.ArtistAlbum).select(.{}).count().execute(env.repo) orelse unreachable;
            const albumsong_offset = try jetzig.database.Query(.AlbumSong).select(.{}).count().execute(env.repo) orelse unreachable;
            const artistsong_offset = try jetzig.database.Query(.ArtistSong).select(.{}).count().execute(env.repo) orelse unreachable;

            // Inserts
            const artistalbum_insert = jetzig.database.Query(.ArtistAlbum).insert(.{ .id = 1 + artistalbum_offset, .artist_id = artist_id, .album_id = album_id });
            const albumsong_insert = jetzig.database.Query(.AlbumSong).insert(.{ .id = 1 + albumsong_offset, .song_id = song_id, .album_id = album_id });
            const artistsong_insert = jetzig.database.Query(.ArtistSong).insert(.{ .id = 1 + artistsong_offset, .artist_id = artist_id, .song_id = song_id });
            const album_insert = jetzig.database.Query(.Album).insert(.{ .id = album_id, .title = scrobble.album, .song_num = 0, .length = 0.0, .play_count = 0, .holiday = false, .compilation = false, .deluxe = false, .live = false });
            const artist_insert = jetzig.database.Query(.Artist).insert(.{ .id = artist_id, .name = scrobble.artist, .album_num = 0, .song_num = 0, .play_count = 0 });
            const song_insert = jetzig.database.Query(.Song).insert(.{ .id = song_id, .title = scrobble.track, .length = 0.0, .hidden = false, .holiday = false, .play_count = 0 });

            // Checks
            const artistalbum_check = try jetzig.database.Query(.ArtistAlbum).where(.{ .{ .artist_id = artist_id }, .AND, .{ .album_id = album_id } }).count().execute(env.repo);
            const albumsong_check = try jetzig.database.Query(.AlbumSong).where(.{ .{ .album_id = album_id }, .AND, .{ .song_id = song_id } }).count().execute(env.repo);
            const artistsong_check = try jetzig.database.Query(.ArtistSong).where(.{ .{ .artist_id = artist_id }, .AND, .{ .song_id = song_id } }).count().execute(env.repo);
            const album_check = try jetzig.database.Query(.Album).where(.{.{ .id = album_id }}).count().execute(env.repo);
            const artist_check = try jetzig.database.Query(.Artist).where(.{.{ .id = artist_id }}).count().execute(env.repo);
            const song_check = try jetzig.database.Query(.Song).where(.{.{ .id = song_id }}).count().execute(env.repo);

            // Insert into Intermediate Tables
            if (artistalbum_check == 0) try env.repo.execute(artistalbum_insert);
            if (albumsong_check == 0) try env.repo.execute(albumsong_insert);
            if (artistsong_check == 0) try env.repo.execute(artistsong_insert);

            if (album_check == 0) try env.repo.execute(album_insert);
            if (artist_check == 0) try env.repo.execute(artist_insert);
            if (song_check == 0) try env.repo.execute(song_insert);

            const scrobble_offset = try jetzig.database.Query(.Scrobble).select(.{}).count().execute(env.repo) orelse unreachable;
            try jetzig.database.Query(.Scrobble).insert(.{ .id = scrobble_offset + 1, .song_id = song_id, .album_id = album_id, .artist_id = artist_id, .date = scrobble.date }).execute(env.repo);
        }
    }
}