module.add(user,problem,record)

hydro/model/problem.js

@@ -0,0 +1,87 @@
+const
+    validator = require('../lib/validator'),
+    { ProblemNotFoundError } = require('../error'),
+    db = require('../service/db.js'),
+    coll = db.collection('problem'),
+    coll_status = db.collection('problem.status');
+
+/**
+ * @param {string} domainId 
+ * @param {string} title 
+ * @param {string} content 
+ * @param {number} owner 
+ * @param {number} pid 
+ * @param {import('bson').ObjectID} data 
+ * @param {string[]} category 
+ * @param {string[]} tag 
+ * @param {boolean} hidden 
+ */
+async function add({
+    domainId,
+    title,
+    content,
+    owner,
+    pid = null,
+    data = null,
+    category = [],
+    tag = [],
+    hidden = false
+}) {
+    validator.checkTitle(title);
+    validator.checkContent(content);
+    await coll.insertOne({
+        domainId,
+        content,
+        owner,
+        pid,
+        title,
+        data,
+        category,
+        tag,
+        hidden,
+        nSubmit: 0,
+        nAccept: 0
+    });
+    return pid;
+}
+async function get({ domainId, pid, uid }) {
+    pid = parseInt(pid) || pid;
+    let pdoc = await coll.findOne({ domainId, pid });
+    if (!pdoc) throw new ProblemNotFoundError(domainId, pid);
+    pdoc.psdoc = uid ?
+        await coll_status.findOne({ domainId, pid, uid }) :
+        null;
+    return pdoc;
+}
+async function getMany(query, sort, page, limit) {
+    return await coll.find(query).sort(sort).skip((page - 1) * limit).limit(limit).toArray();
+}
+async function edit(domainId, pid, $set) {
+    if ($set.title) validator.checkTitle($set.title);
+    if ($set.content) validator.checkContent($set.content);
+    await coll.findOneAndUpdate({ domainId, pid }, { $set });
+    let pdoc = await coll.findOne({ domainId, pid });
+    if (!pdoc) throw new ProblemNotFoundError(domainId, pid);
+    return pdoc;
+}
+async function count(query) {
+    return await coll.find(query).count();
+}
+async function random(query) {
+    let pdocs = coll.find(query);
+    let pcount = await pdocs.count();
+    if (pcount) {
+        let pdoc = await pdocs.skip(Math.floor(Math.random() * pcount)).limit(1).toArray()[0];
+        return pdoc.pid;
+    } else return null;
+
+}
+
+module.exports = {
+    add,
+    get,
+    getMany,
+    edit,
+    count,
+    random
+};