<?php

declare(strict_types=1);

namespace DoctrineMigrations;

use Doctrine\DBAL\Schema\Schema;
use Doctrine\Migrations\AbstractMigration;

final class Version20260227181000 extends AbstractMigration
{
    public function getDescription(): string
    {
        return 'Apply SQLite-safe table rebuilds to remove legacy Spotify and unused album columns';
    }

    public function up(Schema $schema): void
    {
        if ($this->isSqlite()) {
            $this->migrateSqlite();
            return;
        }

        if ($this->hasTable($schema, 'albums')) {
            $this->addSql('ALTER TABLE albums DROP CONSTRAINT IF EXISTS FK_F4E2474FB03A8386');
            $this->addSql('DROP INDEX IF EXISTS IDX_F4E2474FB03A8386');
            $this->addSql('DROP INDEX IF EXISTS uniq_album_local_id');
            $this->addSql('DROP INDEX IF EXISTS UNIQ_F4E2474F5D5A2101');
            $this->addSql('DROP INDEX IF EXISTS UNIQ_F4E2474FA905FC5C');

            if ($this->hasColumn($schema, 'albums', 'created_by_id')) {
                $this->addSql('ALTER TABLE albums DROP COLUMN created_by_id');
            }
            if ($this->hasColumn($schema, 'albums', 'local_id')) {
                $this->addSql('ALTER TABLE albums DROP COLUMN local_id');
            }
            if ($this->hasColumn($schema, 'albums', 'cover_url')) {
                $this->addSql('ALTER TABLE albums DROP COLUMN cover_url');
            }
            if ($this->hasColumn($schema, 'albums', 'cover_image_path')) {
                $this->addSql('ALTER TABLE albums DROP COLUMN cover_image_path');
            }
            if ($this->hasColumn($schema, 'albums', 'spotify_id')) {
                $this->addSql('ALTER TABLE albums DROP COLUMN spotify_id');
            }
        }

        if ($this->hasColumn($schema, 'album_tracks', 'spotify_track_id')) {
            $this->addSql('ALTER TABLE album_tracks DROP COLUMN spotify_track_id');
        }

        if ($this->hasColumn($schema, 'reviews', 'spotify_album_id')) {
            $this->addSql('ALTER TABLE reviews DROP COLUMN spotify_album_id');
        }
    }

    public function down(Schema $schema): void
    {
        // Forward-only migration: reverting would require data-loss-prone table rewrites.
    }

    private function migrateSqlite(): void
    {
        $this->addSql('PRAGMA foreign_keys = OFF');

        $this->addSql(
            "CREATE TABLE albums_new (
                id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
                external_id VARCHAR(64) DEFAULT NULL,
                source VARCHAR(16) NOT NULL,
                name VARCHAR(255) NOT NULL,
                artists CLOB NOT NULL,
                release_date VARCHAR(20) DEFAULT NULL,
                total_tracks INTEGER NOT NULL,
                external_url VARCHAR(1024) DEFAULT NULL,
                created_at DATETIME NOT NULL,
                updated_at DATETIME NOT NULL,
                genres CLOB NOT NULL DEFAULT '[]'
            )"
        );
        $this->addSql(
            "INSERT INTO albums_new (
                id, external_id, source, name, artists, release_date, total_tracks, external_url, created_at, updated_at, genres
            )
            SELECT
                id,
                CASE
                    WHEN external_id IS NOT NULL AND TRIM(external_id) <> '' THEN external_id
                    WHEN local_id IS NOT NULL AND TRIM(local_id) <> '' THEN local_id
                    ELSE 'legacy:' || id
                END AS external_id,
                CASE
                    WHEN source = 'spotify' OR source IS NULL OR TRIM(source) = '' THEN 'external'
                    ELSE source
                END AS source,
                name,
                artists,
                release_date,
                total_tracks,
                external_url,
                created_at,
                updated_at,
                COALESCE(genres, '[]') AS genres
            FROM albums"
        );
        $this->addSql('DROP TABLE albums');
        $this->addSql('ALTER TABLE albums_new RENAME TO albums');
        $this->addSql('CREATE UNIQUE INDEX IF NOT EXISTS uniq_album_external_id ON albums (external_id)');

        $this->addSql(
            "CREATE TABLE album_tracks_new (
                id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
                album_id INTEGER NOT NULL,
                external_track_id VARCHAR(64) DEFAULT NULL,
                disc_number INTEGER NOT NULL,
                track_number INTEGER NOT NULL,
                name VARCHAR(512) NOT NULL,
                duration_ms INTEGER NOT NULL,
                preview_url VARCHAR(1024) DEFAULT NULL,
                CONSTRAINT FK_5E4A3B3B1137ABCF FOREIGN KEY (album_id) REFERENCES albums (id) ON DELETE CASCADE NOT DEFERRABLE INITIALLY IMMEDIATE
            )"
        );
        $this->addSql(
            "INSERT INTO album_tracks_new (
                id, album_id, external_track_id, disc_number, track_number, name, duration_ms, preview_url
            )
            SELECT
                id,
                album_id,
                CASE
                    WHEN external_track_id IS NOT NULL AND TRIM(external_track_id) <> '' THEN external_track_id
                    WHEN spotify_track_id IS NOT NULL AND TRIM(spotify_track_id) <> '' THEN spotify_track_id
                    ELSE NULL
                END AS external_track_id,
                disc_number,
                track_number,
                name,
                duration_ms,
                preview_url
            FROM album_tracks"
        );
        $this->addSql('DROP TABLE album_tracks');
        $this->addSql('ALTER TABLE album_tracks_new RENAME TO album_tracks');
        $this->addSql('CREATE INDEX IF NOT EXISTS IDX_5E4A3B3B1137ABCF ON album_tracks (album_id)');
        $this->addSql('CREATE UNIQUE INDEX IF NOT EXISTS uniq_album_disc_track ON album_tracks (album_id, disc_number, track_number)');

        $this->addSql('PRAGMA foreign_keys = ON');
    }

    private function hasTable(Schema $schema, string $tableName): bool
    {
        return $schema->hasTable($tableName);
    }

    private function hasColumn(Schema $schema, string $tableName, string $columnName): bool
    {
        return $this->hasTable($schema, $tableName) && $schema->getTable($tableName)->hasColumn($columnName);
    }

    private function isSqlite(): bool
    {
        return $this->connection->getDatabasePlatform()->getName() === 'sqlite';
    }
}