import type { Knex } from 'knex';
import type { FnHelperOptions } from '../types.js';
import { FnHelper } from '../types.js';

const parseLocaltime = (columnType?: string) => {
	if (columnType === 'timestamp') {
		return ` AT TIME ZONE 'UTC'`;
	}

	return '';
};

export class FnHelperMSSQL extends FnHelper {
	year(table: string, column: string, options: FnHelperOptions): Knex.Raw {
		return this.knex.raw(`DATEPART(year, ??.??${parseLocaltime(options?.type)})`, [table, column]);
	}

	month(table: string, column: string, options: FnHelperOptions): Knex.Raw {
		return this.knex.raw(`DATEPART(month, ??.??${parseLocaltime(options?.type)})`, [table, column]);
	}

	week(table: string, column: string, options: FnHelperOptions): Knex.Raw {
		return this.knex.raw(`DATEPART(week, ??.??${parseLocaltime(options?.type)})`, [table, column]);
	}

	day(table: string, column: string, options: FnHelperOptions): Knex.Raw {
		return this.knex.raw(`DATEPART(day, ??.??${parseLocaltime(options?.type)})`, [table, column]);
	}

	weekday(table: string, column: string, options: FnHelperOptions): Knex.Raw {
		return this.knex.raw(`DATEPART(weekday, ??.??${parseLocaltime(options?.type)})`, [table, column]);
	}

	hour(table: string, column: string, options: FnHelperOptions): Knex.Raw {
		return this.knex.raw(`DATEPART(hour, ??.??${parseLocaltime(options?.type)})`, [table, column]);
	}

	minute(table: string, column: string, options: FnHelperOptions): Knex.Raw {
		return this.knex.raw(`DATEPART(minute, ??.??${parseLocaltime(options?.type)})`, [table, column]);
	}

	second(table: string, column: string, options: FnHelperOptions): Knex.Raw {
		return this.knex.raw(`DATEPART(second, ??.??${parseLocaltime(options?.type)})`, [table, column]);
	}

	count(table: string, column: string, options?: FnHelperOptions): Knex.Raw<any> {
		const collectionName = options?.originalCollectionName || table;
		const type = this.schema.collections?.[collectionName]?.fields?.[column]?.type ?? 'unknown';

		if (type === 'json') {
			return this.knex.raw(`(SELECT COUNT(*) FROM OPENJSON(??.??, '$'))`, [table, column]);
		}

		if (type === 'alias') {
			return this._relationalCount(table, column, options);
		}

		throw new Error(`Couldn't extract type from ${table}.${column}`);
	}
}
