/**
 * Migration runner - discovers, orders, and executes database migrations.
 * Mirrors the pattern from @serve.zone/nupst.
 */

import type { TQueryFunction } from '../types.ts';
import { logger } from '../../logging.ts';
import { getErrorMessage } from '../../utils/error.ts';

import { Migration001Initial } from './migration-001-initial.ts';
import { Migration002TimestampsToReal } from './migration-002-timestamps-to-real.ts';
import { Migration003DomainManagement } from './migration-003-domain-management.ts';
import { Migration004RegistryColumns } from './migration-004-registry-columns.ts';
import { Migration005RegistryTokens } from './migration-005-registry-tokens.ts';
import { Migration006DropRegistryToken } from './migration-006-drop-registry-token.ts';
import { Migration007PlatformServices } from './migration-007-platform-services.ts';
import { Migration008CertPemContent } from './migration-008-cert-pem-content.ts';
import { Migration009BackupSystem } from './migration-009-backup-system.ts';
import { Migration010BackupSchedules } from './migration-010-backup-schedules.ts';
import { Migration011ScopeColumns } from './migration-011-scope-columns.ts';
import { Migration012GfsRetention } from './migration-012-gfs-retention.ts';
import type { BaseMigration } from './base-migration.ts';

export class MigrationRunner {
  private query: TQueryFunction;
  private migrations: BaseMigration[];

  constructor(query: TQueryFunction) {
    this.query = query;

    // Register all migrations in order
    this.migrations = [
      new Migration001Initial(),
      new Migration002TimestampsToReal(),
      new Migration003DomainManagement(),
      new Migration004RegistryColumns(),
      new Migration005RegistryTokens(),
      new Migration006DropRegistryToken(),
      new Migration007PlatformServices(),
      new Migration008CertPemContent(),
      new Migration009BackupSystem(),
      new Migration010BackupSchedules(),
      new Migration011ScopeColumns(),
      new Migration012GfsRetention(),
    ].sort((a, b) => a.version - b.version);
  }

  /** Run all pending migrations */
  run(): void {
    try {
      const currentVersion = this.getMigrationVersion();
      logger.info(`Current database migration version: ${currentVersion}`);

      let applied = 0;
      for (const migration of this.migrations) {
        if (migration.version <= currentVersion) continue;

        logger.info(`Running ${migration.getName()}...`);
        migration.up(this.query);
        this.setMigrationVersion(migration.version);
        logger.success(`${migration.getName()} completed`);
        applied++;
      }

      if (applied > 0) {
        logger.success(`Applied ${applied} migration(s)`);
      }
    } catch (error) {
      logger.error(`Migration failed: ${getErrorMessage(error)}`);
      if (error instanceof Error && error.stack) {
        logger.error(`Stack: ${error.stack}`);
      }
      throw error;
    }
  }

  /** Get current migration version from the migrations table */
  private getMigrationVersion(): number {
    try {
      const result = this.query<{ version?: number | null; [key: number]: unknown }>(
        'SELECT MAX(version) as version FROM migrations',
      );
      if (result.length === 0) return 0;

      const versionValue = result[0].version ?? (result[0] as Record<number, unknown>)[0];
      return versionValue !== null && versionValue !== undefined ? Number(versionValue) : 0;
    } catch {
      // Table might not exist yet on fresh databases
      return 0;
    }
  }

  /** Record a migration version as applied */
  private setMigrationVersion(version: number): void {
    this.query('INSERT INTO migrations (version, applied_at) VALUES (?, ?)', [
      version,
      Date.now(),
    ]);
  }
}