Step toward a one-page application

[vchess.git] / models / Problem.js

var db = require("../utils/database");

/*
 * Structure:
 *   id: problem number (int)
 *   uid: user id (int)
 *   vid: variant id (int)
 *   added: timestamp
 *   instructions: text
 *   solution: text
 */

const ProblemModel =
{
	create: function(uid, vid, fen, instructions, solution, cb)
	{
		db.serialize(function() {
			const insertQuery =
				"INSERT INTO Problems (added, uid, vid, fen, instructions, solution) " +
				"VALUES (" + Date.now() + "," + uid + "," + vid + ",'" + fen + "',?,?)";
			db.run(insertQuery, [instructions, solution], err => {
				if (!!err)
					return cb(err);
				db.get("SELECT last_insert_rowid() AS rowid", cb);
			});
		});
	},

	getOne: function(id, callback)
	{
		db.serialize(function() {
			const query =
				"SELECT * " +
				"FROM Problems " +
				"WHERE id = " + id;
			db.get(query, callback);
		});
	},

	fetchN: function(vid, uid, type, directionStr, lastDt, MaxNbProblems, callback)
	{
		db.serialize(function() {
			let typeLine = "";
			if (uid > 0)
				typeLine = "AND uid " + (type=="others" ? "!=" : "=") + " " + uid;
			const query =
				"SELECT * FROM Problems " +
				"WHERE vid = " + vid +
				"  AND added " + directionStr + " " + lastDt + " " + typeLine + " " +
				"ORDER BY added " + (directionStr=="<" ? "DESC " : "") +
				"LIMIT " + MaxNbProblems;
			db.all(query, callback);
		});
	},

	// TODO: update fails (but insert is OK)
	update: function(id, uid, fen, instructions, solution, cb)
	{
		db.serialize(function() {
			const query =
				"UPDATE Problems SET " +
					"fen = '" + fen + "', " +
					"instructions = ?, " +
					"solution = ? " +
				"WHERE id = " + id + " AND uid = " + uid;
			db.run(query, [instructions,solution], cb);
		});
	},

	remove: function(id, uid)
	{
		db.serialize(function() {
			const query =
				"DELETE FROM Problems " +
				"WHERE id = " + id + " AND uid = " + uid;
			db.run(query);
		});
	},
}

module.exports = ProblemModel;