models/Problem.js

   1 var db = require("../utils/database");
   2
   3 /*
   4  * Structure:
   5  *   id: problem number (int)
   6  *   uid: user id (int)
   7  *   vid: variant id (int)
   8  *   added: timestamp
   9  *   instructions: text
  10  *   solution: text
  11  */
  12
  13 // TODO: callback ?
  14 exports.create = function(vname, fen, instructions, solution)
  15 {
  16     db.serialize(function() {
  17         const vidQuery =
  18             "SELECT id " +
  19             "FROM Variants " +
  20             "WHERE name = '" + vname + "'";
  21         db.get(vidQuery, (err,variant) => {
  22             const insertQuery =
  23                 "INSERT INTO Problems (added, vid, fen, instructions, solution) VALUES " +
  24                 "(" +
  25                     Date.now() + "," +
  26                     variant.id + "," +
  27                     fen + "," +
  28                     instructions + "," +
  29                     solution +
  30                 ")";
  31             db.run(insertQuery);
  32         });
  33     });
  34 }
  35
  36 exports.getById = function(id, callback)
  37 {
  38     db.serialize(function() {
  39         const query =
  40             "SELECT * FROM Problems " +
  41             "WHERE id ='" + id + "'";
  42         db.get(query, callback);
  43     });
  44 }
  45
  46 exports.getOne = function(vname, pid, callback)
  47 {
  48     db.serialize(function() {
  49         const query =
  50             "SELECT * " +
  51             "FROM Problems " +
  52             "WHERE id = " + pid;
  53         db.get(query, callback);
  54     });
  55 }
  56
  57 exports.fetchN = function(vname, uid, type, directionStr, lastDt, MaxNbProblems, callback)
  58 {
  59     db.serialize(function() {
  60         let typeLine = "";
  61         if (uid > 0)
  62             typeLine = "AND id " + (type=="others" ? "!=" : "=") + " " + uid;
  63         const query =
  64             "SELECT * FROM Problems " +
  65             "WHERE vid = (SELECT id FROM Variants WHERE name = '" + vname + "') " +
  66             "  AND added " + directionStr + " " + lastDt + " " + typeLine + " " +
  67             "ORDER BY added " + (directionStr=="<" ? "DESC " : "") +
  68             "LIMIT " + MaxNbProblems,
  69         db.all(query, callback);
  70     });
  71 }
  72
  73 exports.update = function(id, uid, fen, instructions, solution)
  74 {
  75     db.serialize(function() {
  76         const query =
  77             "UPDATE Problems " +
  78                 "fen = " + fen + ", " +
  79                 "instructions = " + instructions + ", " +
  80                 "solution = " + solution + " " +
  81             "WHERE id = " + id + " AND uid = " + uid;
  82         db.run(query);
  83     });
  84 }
  85
  86 exports.remove = function(id, uid)
  87 {
  88     db.serialize(function() {
  89         const query =
  90             "DELETE FROM Problems " +
  91             "WHERE id = " + id + " AND uid = " + uid;
  92         db.run(query);
  93     });
  94 }