'use strict';

module.exports = {
  async up(queryInterface) {
    await queryInterface.sequelize.transaction(async (transaction) => {
      await queryInterface.sequelize.query(`
        ALTER TABLE community.vocab_course
          ADD COLUMN IF NOT EXISTS cefr_level TEXT,
          ADD COLUMN IF NOT EXISTS course_kind TEXT NOT NULL DEFAULT 'core',
          ADD COLUMN IF NOT EXISTS prerequisite_course_id INTEGER NULL
            REFERENCES community.vocab_course(id) ON DELETE SET NULL;

        CREATE TABLE IF NOT EXISTS community.vocab_conversation_session (
          id SERIAL PRIMARY KEY,
          user_id INTEGER NOT NULL REFERENCES community."user"(id) ON DELETE CASCADE,
          lesson_id INTEGER NOT NULL REFERENCES community.vocab_course_lesson(id) ON DELETE CASCADE,
          scenario JSONB NOT NULL DEFAULT '{}'::jsonb,
          turns JSONB NOT NULL DEFAULT '[]'::jsonb,
          summary JSONB NULL,
          status TEXT NOT NULL DEFAULT 'active',
          created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
          updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
        );
        CREATE INDEX IF NOT EXISTS vocab_conversation_session_user_lesson_idx
          ON community.vocab_conversation_session(user_id, lesson_id, updated_at DESC);

        CREATE TABLE IF NOT EXISTS community.vocab_listening_activity (
          id SERIAL PRIMARY KEY,
          lesson_id INTEGER NOT NULL REFERENCES community.vocab_course_lesson(id) ON DELETE CASCADE,
          audio_url TEXT NOT NULL,
          transcript TEXT NOT NULL,
          translation TEXT NULL,
          speaker_profile JSONB NOT NULL DEFAULT '{}'::jsonb,
          speed TEXT NOT NULL DEFAULT 'natural',
          questions JSONB NOT NULL DEFAULT '[]'::jsonb,
          created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
        );
        CREATE INDEX IF NOT EXISTS vocab_listening_activity_lesson_idx
          ON community.vocab_listening_activity(lesson_id);
      `, { transaction });
    });
  },

  async down(queryInterface) {
    await queryInterface.sequelize.query(`
      DROP TABLE IF EXISTS community.vocab_listening_activity;
      DROP TABLE IF EXISTS community.vocab_conversation_session;
      ALTER TABLE community.vocab_course
        DROP COLUMN IF EXISTS prerequisite_course_id,
        DROP COLUMN IF EXISTS course_kind,
        DROP COLUMN IF EXISTS cefr_level;
    `);
  }
};