'use strict';

/** @type {import('sequelize-cli').Migration} */
module.exports = {
  async up (queryInterface, Sequelize) {
    console.log('Creating guest_sessions table...');
    
    await queryInterface.createTable('guest_sessions', {
      id: {
        type: Sequelize.CHAR(36),
        primaryKey: true,
        allowNull: false,
        comment: 'UUID primary key'
      },
      guest_id: {
        type: Sequelize.STRING(100),
        allowNull: false,
        unique: true,
        comment: 'Unique guest identifier'
      },
      session_token: {
        type: Sequelize.STRING(500),
        allowNull: false,
        unique: true,
        comment: 'JWT session token'
      },
      device_id: {
        type: Sequelize.STRING(255),
        allowNull: true,
        comment: 'Device identifier (optional)'
      },
      ip_address: {
        type: Sequelize.STRING(45),
        allowNull: true,
        comment: 'IP address (supports IPv6)'
      },
      user_agent: {
        type: Sequelize.TEXT,
        allowNull: true,
        comment: 'Browser user agent string'
      },
      quizzes_attempted: {
        type: Sequelize.INTEGER,
        allowNull: false,
        defaultValue: 0,
        comment: 'Number of quizzes attempted by guest'
      },
      max_quizzes: {
        type: Sequelize.INTEGER,
        allowNull: false,
        defaultValue: 3,
        comment: 'Maximum quizzes allowed for this guest'
      },
      expires_at: {
        type: Sequelize.DATE,
        allowNull: false,
        comment: 'Session expiration timestamp'
      },
      is_converted: {
        type: Sequelize.BOOLEAN,
        allowNull: false,
        defaultValue: false,
        comment: 'Whether guest converted to registered user'
      },
      converted_user_id: {
        type: Sequelize.CHAR(36),
        allowNull: true,
        references: {
          model: 'users',
          key: 'id'
        },
        onUpdate: 'CASCADE',
        onDelete: 'SET NULL',
        comment: 'User ID if guest converted to registered user'
      },
      created_at: {
        type: Sequelize.DATE,
        allowNull: false,
        defaultValue: Sequelize.literal('CURRENT_TIMESTAMP')
      },
      updated_at: {
        type: Sequelize.DATE,
        allowNull: false,
        defaultValue: Sequelize.literal('CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP')
      }
    }, {
      charset: 'utf8mb4',
      collate: 'utf8mb4_unicode_ci',
      engine: 'InnoDB'
    });

    // Add indexes
    await queryInterface.addIndex('guest_sessions', ['guest_id'], {
      unique: true,
      name: 'idx_guest_sessions_guest_id'
    });

    await queryInterface.addIndex('guest_sessions', ['session_token'], {
      unique: true,
      name: 'idx_guest_sessions_session_token'
    });

    await queryInterface.addIndex('guest_sessions', ['expires_at'], {
      name: 'idx_guest_sessions_expires_at'
    });

    await queryInterface.addIndex('guest_sessions', ['is_converted'], {
      name: 'idx_guest_sessions_is_converted'
    });

    await queryInterface.addIndex('guest_sessions', ['converted_user_id'], {
      name: 'idx_guest_sessions_converted_user_id'
    });

    await queryInterface.addIndex('guest_sessions', ['device_id'], {
      name: 'idx_guest_sessions_device_id'
    });

    await queryInterface.addIndex('guest_sessions', ['created_at'], {
      name: 'idx_guest_sessions_created_at'
    });

    console.log('✅ Guest sessions table created successfully with indexes');
  },

  async down (queryInterface, Sequelize) {
    console.log('Dropping guest_sessions table...');
    await queryInterface.dropTable('guest_sessions');
    console.log('✅ Guest sessions table dropped successfully');
  }
};