import * as api from '../../client/src/api';
import { EndpointError, EndpointHandler, catchUnhandledErrors } from './types';
import Knex from 'knex';

export const CreateTagEndpointHandler: EndpointHandler = async (req: any, res: any, knex: Knex) => {
    if (!api.checkCreateTagRequest(req)) {
        const e: EndpointError = {
            internalMessage: 'Invalid CreateTag request: ' + JSON.stringify(req.body),
            httpStatus: 400
        };
        throw e;
    }
    const reqObject: api.CreateTagRequest = req.body;
    const { id: userId } = req.user;

    console.log("User ", userId, ": Create Tag ", reqObject);

    await knex.transaction(async (trx) => {
        try {
            // If applicable, retrieve the parent tag.
            const maybeParent: number | undefined =
                reqObject.parentId ?
                    (await trx.select('id')
                        .from('tags')
                        .where({ 'user': userId })
                        .where({ 'id': reqObject.parentId }))[0]['id'] :
                    undefined;

            // Check if the parent was found, if applicable.
            if (reqObject.parentId && maybeParent !== reqObject.parentId) {
                const e: EndpointError = {
                    internalMessage: 'Could not find parent tag for CreateTag request: ' + JSON.stringify(req.body),
                    httpStatus: 400
                };
                throw e;
            }

            // Create the new tag.
            var tag: any = {
                name: reqObject.name,
                user: userId,
            };
            if (maybeParent) {
                tag['parentId'] = maybeParent;
            }
            const tagId = (await trx('tags')
                .insert(tag)
                .returning('id') // Needed for Postgres
            )[0];

            // Respond to the request.
            const responseObject: api.CreateTagResponse = {
                id: tagId
            };
            res.status(200).send(responseObject);

        } catch (e) {
            catchUnhandledErrors(e);
            trx.rollback();
        }
    })
}