import * as SQLite from 'expo-sqlite';
import { Contact } from '@/store/useContactStore';
import { dbToContact } from '@/lib/contactHelpers';

let db: SQLite.SQLiteDatabase | null = null;

export async function getDatabase(): Promise<SQLite.SQLiteDatabase> {
  if (!db) {
    db = await SQLite.openDatabaseAsync('territorylog.db');
    await initSchema(db);
  }
  return db;
}

async function initSchema(database: SQLite.SQLiteDatabase): Promise<void> {
  await database.execAsync(`
    PRAGMA journal_mode = WAL;
    PRAGMA foreign_keys = ON;

    CREATE TABLE IF NOT EXISTS users (
      id TEXT PRIMARY KEY,
      display_name TEXT NOT NULL,
      share_id TEXT UNIQUE NOT NULL,
      is_self INTEGER DEFAULT 1,
      created_at INTEGER NOT NULL
    );

    CREATE TABLE IF NOT EXISTS territories (
      id TEXT PRIMARY KEY,
      territory_code TEXT UNIQUE NOT NULL,
      municipality TEXT,
      barangay TEXT,
      area TEXT,
      block TEXT,
      assigned_to TEXT,
      created_at INTEGER NOT NULL,
      updated_at INTEGER NOT NULL
    );

    CREATE TABLE IF NOT EXISTS contacts (
      id TEXT PRIMARY KEY,
      owner_id TEXT NOT NULL,
      full_name TEXT NOT NULL,
      address TEXT,
      household_count INTEGER DEFAULT 1,
      gender TEXT,
      category TEXT NOT NULL,
      status TEXT DEFAULT 'Active',
      tags TEXT DEFAULT '[]',
      notes TEXT,
      territory_code TEXT REFERENCES territories(territory_code),
      latitude REAL,
      longitude REAL,
      created_at INTEGER NOT NULL,
      updated_at INTEGER NOT NULL,
      deleted_at INTEGER
    );

    CREATE TABLE IF NOT EXISTS visits (
      id TEXT PRIMARY KEY,
      contact_id TEXT NOT NULL REFERENCES contacts(id),
      visited_by_name TEXT NOT NULL,
      visited_by_id TEXT NOT NULL,
      visit_date INTEGER NOT NULL,
      topic TEXT,
      response TEXT,
      remarks TEXT,
      next_visit_date INTEGER,
      created_at INTEGER NOT NULL,
      updated_at INTEGER NOT NULL
    );

    CREATE TABLE IF NOT EXISTS topics (
      id TEXT PRIMARY KEY,
      name TEXT UNIQUE NOT NULL,
      is_default INTEGER DEFAULT 0,
      created_at INTEGER NOT NULL
    );

    CREATE TABLE IF NOT EXISTS sync_log (
      id TEXT PRIMARY KEY,
      partner_id TEXT NOT NULL,
      partner_name TEXT,
      synced_at INTEGER NOT NULL,
      sent_count INTEGER DEFAULT 0,
      received_count INTEGER DEFAULT 0
    );

    CREATE INDEX IF NOT EXISTS idx_contacts_name ON contacts(full_name);
    CREATE INDEX IF NOT EXISTS idx_contacts_status ON contacts(status);
    CREATE INDEX IF NOT EXISTS idx_contacts_territory ON contacts(territory_code);
    CREATE INDEX IF NOT EXISTS idx_visits_contact ON visits(contact_id);
    CREATE INDEX IF NOT EXISTS idx_visits_date ON visits(visit_date);
  `);

  // Seed default topics
  const now = Math.floor(Date.now() / 1000);
  const defaultTopics = [
    { id: 't1', name: 'The Kingdom of God' },
    { id: 't2', name: 'Paradise Earth' },
    { id: 't3', name: 'Life After Death' },
    { id: 't4', name: "The Bible's Reliability" },
    { id: 't5', name: "God's Name (Jehovah)" },
    { id: 't6', name: 'Why Bad Things Happen' },
    { id: 't7', name: 'Jesus Christ' },
    { id: 't8', name: 'The Resurrection' },
    { id: 't9', name: 'Family Happiness' },
  ];
  
  for (const topic of defaultTopics) {
    await database.runAsync(
      'INSERT OR IGNORE INTO topics (id, name, is_default, created_at) VALUES (?, ?, 1, ?)',
      [topic.id, topic.name, now]
    );
  }
}

// ── Map helpers ──────────────────────────────────────────────────────────────

export async function getContactsWithGPS(): Promise<Contact[]> {
  const database = await getDatabase();
  const result = await database.getAllAsync<any>(
    `SELECT * FROM contacts WHERE latitude IS NOT NULL AND longitude IS NOT NULL AND deleted_at IS NULL ORDER BY full_name`
  );
  return result.map(dbToContact);
}

export async function getAllContactsForMap(): Promise<Contact[]> {
  const database = await getDatabase();
  const result = await database.getAllAsync<any>(
    `SELECT * FROM contacts WHERE deleted_at IS NULL ORDER BY full_name`
  );
  return result.map(dbToContact);
}