import { STORAGE_KEYS } from '@/common/constants/storageKeys';
import type { AbstractPowerSyncDatabase, PowerSyncBackendConnector } from '@powersync/react-native';
import * as SecureStore from 'expo-secure-store';

const POWERSYNC_URL = process.env.EXPO_PUBLIC_POWERSYNC_URL!;
const API_URL = process.env.EXPO_PUBLIC_API_URL!;

export class SyncConnector implements PowerSyncBackendConnector {
  async fetchCredentials() {
    const sessionToken = await SecureStore.getItemAsync(STORAGE_KEYS.SESSION_TOKEN);
    if (!sessionToken) throw new Error('No session token');

    const response = await fetch(`${API_URL}/api/auth/sync-engine-token`, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        Authorization: `Bearer ${sessionToken}`,
      },
    });

    if (!response.ok) throw new Error('Failed to get sync engine token');

    const { syncEngineToken } = await response.json();
    return { endpoint: POWERSYNC_URL, token: syncEngineToken };
  }

  async uploadData(database: AbstractPowerSyncDatabase): Promise<void> {
    const transaction = await database.getNextCrudTransaction();
    if (!transaction) return;

    const operations = transaction.crud
      .filter(op => !this.isDemoData(op.opData))
      .map(op => ({ id: op.id, table: op.table, op: op.op, opData: op.opData }));

    if (operations.length === 0) {
      await transaction.complete();
      return;
    }

    const sessionToken = await SecureStore.getItemAsync(STORAGE_KEYS.SESSION_TOKEN);
    const response = await fetch(`${API_URL}/api/sync/upload`, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        Authorization: `Bearer ${sessionToken}`,
      },
      body: JSON.stringify({ operations }),
    });

    if (!response.ok) {
      const error = await response.json();
      throw new Error(error.message || 'Upload failed');
    }

    await transaction.complete();
  }

  private isDemoData(opData: Record<string, unknown> | undefined): boolean {
    if (!opData) return false;
    return opData.profile_id === 'demo' || opData.workos_user_id === 'demo';
  }
}