/*
Copyright © 2023 Philipp Wolfer <phw@uploadedlobster.com>

This file is part of Scotty.

Scotty is free software: you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
Foundation, either version 3 of the License, or (at your option) any later version.

Scotty is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with
Scotty. If not, see <https://www.gnu.org/licenses/>.
*/

package jspf

import (
	"encoding/json"
	"os"
	"time"

	"github.com/spf13/viper"
	"go.uploadedlobster.com/scotty/models"
)

type JspfBackend struct {
	filePath   string
	title      string
	creator    string
	identifier string
	tracks     []Track
}

func (b *JspfBackend) Name() string { return "jspf" }

func (b *JspfBackend) FromConfig(config *viper.Viper) models.Backend {
	b.filePath = config.GetString("file-path")
	b.title = config.GetString("title")
	b.creator = config.GetString("username")
	b.identifier = config.GetString("identifier")
	b.tracks = make([]Track, 0)
	return b
}

func (b *JspfBackend) StartImport() error { return nil }
func (b *JspfBackend) FinishImport() error {
	err := b.writeJspf(b.tracks)
	return err
}

func (b *JspfBackend) ImportLoves(export models.LovesResult, importResult models.ImportResult, progress chan models.Progress) (models.ImportResult, error) {
	for _, love := range export.Loves {
		track := loveAsTrack(love)
		b.tracks = append(b.tracks, track)
		importResult.ImportCount += 1
		importResult.UpdateTimestamp(love.Created)
	}

	progress <- models.Progress{}.FromImportResult(importResult)
	return importResult, nil
}

func loveAsTrack(love models.Love) Track {
	extension := MusicBrainzTrackExtension{
		AddedAt:            love.Created,
		AddedBy:            love.UserName,
		AdditionalMetadata: love.AdditionalInfo,
		ArtistIdentifiers:  make([]string, len(love.ArtistMbids)),
	}

	for i, mbid := range love.ArtistMbids {
		extension.ArtistIdentifiers[i] = "https://musicbrainz.org/artist/" + string(mbid)
	}

	if love.ReleaseMbid != "" {
		extension.ReleaseIdentifier = "https://musicbrainz.org/release/" + string(love.ReleaseMbid)
	}

	track := Track{
		Title:    love.TrackName,
		Album:    love.ReleaseName,
		Creator:  love.ArtistName(),
		TrackNum: love.TrackNumber,
		Extension: map[string]any{
			"https://musicbrainz.org/doc/jspf#track": extension,
		},
	}

	if love.RecordingMbid != "" {
		track.Identifier = append(track.Identifier, "https://musicbrainz.org/recording/"+string(love.RecordingMbid))
	}

	return track
}

func (b JspfBackend) writeJspf(tracks []Track) error {
	playlist := Jspf{
		Playlist: Playlist{
			Title:      b.title,
			Creator:    b.creator,
			Identifier: b.identifier,
			Date:       time.Now(),
			Tracks:     tracks,
		},
	}

	file, err := os.Create(b.filePath)
	if err != nil {
		return err
	}

	defer file.Close()
	jspfJson, err := json.MarshalIndent(playlist, "", "\t")
	if err != nil {
		return err
	}

	_, err = file.Write(jspfJson)
	return err
}