Page model (#1)

* Initial database and page MVC

* Add mocha tests

* Add docs

* Add docs about nedb query options

* Add eslint and editorconfig + husky

* Improve precommit script

* Remove unnecessary dependencies

models/page.js

@@ -0,0 +1,160 @@
+const {pages} = require('../database');
+
+/**
+ * @typedef {Object} PageData
+ * @property {string} _id - page id
+ * @property {string} title - page title
+ * @property {*} body - page body
+ * @property {string} parent - id of parent page
+ *
+ */
+
+/**
+ * @class Page
+ * @class Page model
+ *
+ * @property {string} _id - page id
+ * @property {string} title - page title
+ * @property {*} body - page body
+ * @property {string} _parent - id of parent page
+ */
+class Page {
+  /**
+   * Find and return model of page with given id
+   * @param {string} _id - page id
+   * @returns {Promise<Page>}
+   */
+  static async get(_id) {
+    const data = await pages.findOne({_id});
+
+    return new Page(data);
+  }
+
+  /**
+   * Find all pages which match passed query object
+   *
+   * @param {Object} query
+   * @returns {Promise<Page[]>}
+   */
+  static async getAll(query = {}) {
+    const docs = await pages.find(query);
+
+    return Promise.all(docs.map(doc => new Page(doc)));
+  }
+
+  /**
+   * @constructor
+   *
+   * @param {PageData} data
+   */
+  constructor(data = {}) {
+    if (data === null) {
+      data = {};
+    }
+
+    this.db = pages;
+
+    if (data._id) {
+      this._id = data._id;
+    }
+
+    this.data = data;
+  }
+
+  /**
+   * Set PageData object fields to internal model fields
+   *
+   * @param {PageData} pageData
+   */
+  set data(pageData) {
+    const {title, body, parent} = pageData;
+
+    this.title = title || this.title;
+    this.body = body || this.body;
+    this._parent = parent || this._parent;
+  }
+
+  /**
+   * Return PageData object
+   *
+   * @returns {PageData}
+   */
+  get data() {
+    return {
+      _id: this._id,
+      title: this.title,
+      body: this.body,
+      parent: this._parent
+    };
+  }
+
+  /**
+   * Link given page as parent
+   *
+   * @param {Page} parentPage
+   */
+  set parent(parentPage) {
+    this._parent = parentPage._id;
+  }
+
+  /**
+   * Return parent page model
+   *
+   * @returns {Promise<Page>}
+   */
+  get parent() {
+    return this.db.findOne({_id: this._parent})
+      .then(data => new Page(data));
+  }
+
+  /**
+   * Return child pages models
+   *
+   * @returns {Promise<Page[]>}
+   */
+  get children() {
+    return this.db.find({parent: this._id})
+      .then(data => data.map(page => new Page(page)));
+  }
+
+  /**
+   * Save or update page data in the database
+   *
+   * @returns {Promise<Page>}
+   */
+  async save() {
+    if (!this._id) {
+      const insertedRow = await this.db.insert(this.data);
+
+      this._id = insertedRow._id;
+    } else {
+      await this.db.update({_id: this._id}, this.data);
+    }
+
+    return this;
+  }
+
+  /**
+   * Remove page data from the database
+   *
+   * @returns {Promise<Page>}
+   */
+  async destroy() {
+    await this.db.remove({_id: this._id});
+
+    delete this._id;
+
+    return this;
+  }
+
+  /**
+   * Return readable page data
+   *
+   * @returns {PageData}
+   */
+  toJSON() {
+    return this.data;
+  }
+}
+
+module.exports = Page;