import type { ReversibleMigration, MigrationContext } from '../migration-types';

export class ExpandModelColumnLength1768402473068 implements ReversibleMigration {
	async up({ isSqlite, isPostgres, escape, queryRunner }: MigrationContext) {
		const messagesTable = escape.tableName('chat_hub_messages');
		const sessionsTable = escape.tableName('chat_hub_sessions');
		const modelColumn = escape.columnName('model');

		if (isPostgres) {
			await queryRunner.query(
				`ALTER TABLE ${messagesTable} ALTER COLUMN ${modelColumn} TYPE VARCHAR(256);`,
			);
			await queryRunner.query(
				`ALTER TABLE ${sessionsTable} ALTER COLUMN ${modelColumn} TYPE VARCHAR(256);`,
			);
		} else if (isSqlite) {
			for (const table of [messagesTable, sessionsTable]) {
				await queryRunner.query(`ALTER TABLE ${table} ADD COLUMN "model_tmp" VARCHAR(256);`);
				await queryRunner.query(`UPDATE ${table} SET "model_tmp" = ${modelColumn};`);
				await queryRunner.query(`ALTER TABLE ${table} DROP COLUMN ${modelColumn};`);
				await queryRunner.query(`ALTER TABLE ${table} ADD COLUMN ${modelColumn} VARCHAR(256);`);
				await queryRunner.query(`UPDATE ${table} SET ${modelColumn} = "model_tmp";`);
				await queryRunner.query(`ALTER TABLE ${table} DROP COLUMN "model_tmp";`);
			}
		}
	}

	async down({ isSqlite, isPostgres, escape, queryRunner }: MigrationContext) {
		const messagesTable = escape.tableName('chat_hub_messages');
		const sessionsTable = escape.tableName('chat_hub_sessions');
		const modelColumn = escape.columnName('model');

		// Truncate values longer than 64 chars before changing type
		if (isPostgres) {
			await queryRunner.query(
				`UPDATE ${messagesTable} SET ${modelColumn} = LEFT(${modelColumn}, 64) WHERE LENGTH(${modelColumn}) > 64;`,
			);
			await queryRunner.query(
				`UPDATE ${sessionsTable} SET ${modelColumn} = LEFT(${modelColumn}, 64) WHERE LENGTH(${modelColumn}) > 64;`,
			);
			await queryRunner.query(
				`ALTER TABLE ${messagesTable} ALTER COLUMN ${modelColumn} TYPE VARCHAR(64);`,
			);
			await queryRunner.query(
				`ALTER TABLE ${sessionsTable} ALTER COLUMN ${modelColumn} TYPE VARCHAR(64);`,
			);
		} else if (isSqlite) {
			for (const table of [messagesTable, sessionsTable]) {
				await queryRunner.query(`ALTER TABLE ${table} ADD COLUMN "model_tmp" VARCHAR(64);`);
				await queryRunner.query(`UPDATE ${table} SET "model_tmp" = SUBSTR(${modelColumn}, 1, 64);`);
				await queryRunner.query(`ALTER TABLE ${table} DROP COLUMN ${modelColumn};`);
				await queryRunner.query(`ALTER TABLE ${table} ADD COLUMN ${modelColumn} VARCHAR(64);`);
				await queryRunner.query(`UPDATE ${table} SET ${modelColumn} = "model_tmp";`);
				await queryRunner.query(`ALTER TABLE ${table} DROP COLUMN "model_tmp";`);
			}
		}
	}
}