var MockDatabase = function() {
  this.contacts = [];
  this.messages = [];
  this.tasks = [];
  this._prepared = {};
};

MockDatabase.prototype.exec = function(sql) {
  return [];
};

MockDatabase.prototype.prepare = function(sql) {
  var self = this;
  var stmt = {
    _sql: sql,
    run: function() { return { lastInsertRowid: 1, changes: 1 }; },
    get: function() { return undefined; },
    all: function() { return []; },
  };

  if (sql.indexOf('INSERT INTO contacts') !== -1) {
    stmt.run = function(params) {
      self.contacts.push(params);
      return { lastInsertRowid: self.contacts.length, changes: 1 };
    };
  } else if (sql.indexOf('SELECT * FROM contacts WHERE phone') !== -1) {
    stmt.get = function(phone) {
      return self.contacts.find(function(c) { return c.phone === phone; });
    };
  } else if (sql.indexOf('SELECT * FROM contacts WHERE stage =') !== -1) {
    stmt.all = function(stage) {
      return self.contacts.filter(function(c) { return c.stage === stage; });
    };
  } else if (sql.indexOf('SELECT * FROM contacts WHERE payment_status') !== -1) {
    stmt.all = function(status) {
      return self.contacts.filter(function(c) { return c.payment_status === status; });
    };
  } else if (sql.indexOf('SELECT * FROM messages WHERE contact_phone') !== -1) {
    stmt.all = function(phone) {
      return self.messages.filter(function(m) { return m.contact_phone === phone; });
    };
  }

  return stmt;
};

MockDatabase.prototype.close = function() {};

jest.mock('better-sqlite3', function() {
  return function() {
    return new MockDatabase();
  };
});

describe('4. SQLite Database Layer', function() {
  var db;
  var database;

  beforeEach(function() {
    jest.clearAllMocks();
    database = require('../src/database');
    db = database.initialize(':memory:');
  });

  afterEach(function() {
    if (db && db.close) {
      db.close();
    }
  });

  describe('Database Initialization', function() {
    test('test_database_schema_created_on_init - creates contacts table', function() {
      expect(db).toBeDefined();
    });

    test('test_database_creates_messages_table - messages table exists', function() {
      expect(db).toBeDefined();
    });

    test('test_database_creates_tasks_table - tasks table exists', function() {
      expect(db).toBeDefined();
    });
  });

  describe('Contact Operations', function() {
    test('test_insert_contact - creates new contact', function() {
      var contact = {
        phone: '5511999999999',
        name: 'John Doe',
        stage: 'LEADS DE ENTRADA',
      };

      var result = database.insertContact(db, contact);

      expect(result).toBeDefined();
    });

    test('test_find_contact_by_phone - retrieves contact by phone', function() {
      var contact = {
        phone: '5511999999999',
        name: 'John Doe',
        stage: 'LEADS DE ENTRADA',
      };

      database.insertContact(db, contact);
      var found = database.findContactByPhone(db, '5511999999999');

      expect(found).toBeDefined();
    });

    test('test_update_contact_stage - updates contact stage', function() {
      var contact = {
        phone: '5511999999999',
        name: 'John Doe',
        stage: 'LEADS DE ENTRADA',
      };

      database.insertContact(db, contact);
      var result = database.updateContactStage(db, '5511999999999', 'DECIDINDO');

      expect(result).toBeDefined();
    });

    test('test_list_contacts_by_stage - filters contacts by stage', function() {
      var contacts = database.listContactsByStage(db, 'LEADS DE ENTRADA');

      expect(Array.isArray(contacts)).toBe(true);
    });
  });

  describe('Message Operations', function() {
    test('test_insert_message - creates message record', function() {
      var message = {
        id: 'msg_123',
        contactPhone: '5511999999999',
        body: 'Hello world',
        timestamp: 1234567890,
      };

      var result = database.insertMessage(db, message);

      expect(result).toBeDefined();
    });

    test('test_find_messages_by_contact - retrieves messages for contact', function() {
      var messages = database.findMessagesByContact(db, '5511999999999');

      expect(Array.isArray(messages)).toBe(true);
    });
  });
});