From 1e542ac0e5765a9f12097c2295092c07d52a0402 Mon Sep 17 00:00:00 2001
From: tpoisseau <22891227+tpoisseau@users.noreply.github.com>
Date: Thu, 25 Jul 2024 10:06:43 +0200
Subject: [PATCH] chore: continue implem of custom element

---
 .../init/canvas_editor_element.js             | 156 ++++++++++++++++--
 lib/canvas_editor/init/index.js               |   7 +-
 2 files changed, 144 insertions(+), 19 deletions(-)

diff --git a/lib/canvas_editor/init/canvas_editor_element.js b/lib/canvas_editor/init/canvas_editor_element.js
index ada86299..9ebfcaca 100644
--- a/lib/canvas_editor/init/canvas_editor_element.js
+++ b/lib/canvas_editor/init/canvas_editor_element.js
@@ -1,6 +1,25 @@
 'use strict';
 
-function initCanvasEditorElement(CanvasEditor, Molecule) {
+function initCanvasEditorElement(CanvasEditor, Molecule, ReactionEncoder) {
+  /**
+   * `<openchemlib-editor>` support 4 observable attributes :
+   *
+   * - idcode: init molecule with `Molecule.fromIDCode(idcode)` or reaction with `ReactionEncoder.decode(this.idcode)`.
+   *   fallback to an empty string if not defined.
+   * - fragment: enable or disable fragment on Molecule / Reaction.
+   *   fallback to false if not defined.
+   * - mode: can be either `'molecule'` or `'reaction'`. `CanvasEditorElement.MODE` map these values for enum style.
+   *   fallback to `CanvasEditorElement.MODE.MOLECULE` if not defined.
+   * - readonly: if enable, it do not add toolbar and don't handle user interactions.
+   *   fallback to false.
+   *
+   * @example
+   *
+   * Empty editor:
+   * ```html
+   * <openchemlib-editor></openchemlib-editor>
+   * ```
+   */
   class CanvasEditorElement extends HTMLElement {
     /** @type {{MOLECULE: 'molecule', REACTION: 'reaction'}} */
     static MODE = Object.freeze(
@@ -23,42 +42,121 @@ function initCanvasEditorElement(CanvasEditor, Molecule) {
       CanvasEditorElement.MODE.MOLECULE;
     /** @type {boolean} */ readonly = false;
 
-    /** @type {CanvasEditor} */ #editor;
+    /* --- custom element api --- */
+    /**
+     * @param {Molecule} molecule
+     */
+    setMolecule(molecule) {
+      this.fragment = molecule.isFragment();
+      this.idcode = molecule.getIDCode();
+
+      this.#editor.setMolecule(molecule);
+    }
 
     /**
-     * Custom element added to page.
+     * @return {Molecule}
      */
-    connectedCallback() {
-      const root = this.attachShadow({ mode: 'open' });
-      root.adoptedStyleSheets = [new CSSStyleSheet()];
+    getMolecule() {
+      return this.#editor.getMolecule();
+    }
+
+    /**
+     * @param {Reaction} reaction
+     */
+    setReaction(reaction) {
+      this.fragment = reaction.isFragment();
+      this.idcode = ReactionEncoder.encode(reaction);
 
-      this.#editor = new CanvasEditor(root, {
+      this.#editor.setReaction(reaction);
+    }
+
+    /**
+     * @return {Reaction}
+     */
+    getReaction() {
+      return this.#editor.getReaction();
+    }
+
+    clearAll() {
+      this.#editor.clearAll();
+      this.idcode = '';
+    }
+
+    /* --- internals --- */
+    /** @type {CanvasEditor} */ #editor;
+
+    #initEditor() {
+      this.#editor = new CanvasEditor(this.shadowRoot, {
         readOnly: this.readonly,
         initialMode: this.mode,
       });
+      this.#editor.setOnChangeListener(this.#handleChange);
 
+      this.#initIdCode();
+    }
+
+    #initIdCode() {
       switch (this.mode) {
         case this.constructor.MODE.MOLECULE: {
-          const molecule = Molecule.fromIDCode(this.idcode || '');
-          molecule.setFragment(this.fragment);
-
-          return this.#editor.setMolecule(molecule);
+          return this.#initMolecule();
         }
         case this.constructor.MODE.REACTION: {
-          throw new Error(
-            'Unsupported because `Reaction.fromIDCode` do not exists',
-          );
+          return this.#initReaction();
         }
         default:
           throw new Error(`Mode ${this.mode} is not supported`);
       }
     }
 
+    #initMolecule() {
+      const molecule = Molecule.fromIDCode(this.idcode);
+      molecule.setFragment(this.fragment);
+
+      this.#editor.setMolecule(molecule);
+    }
+
+    #initReaction() {
+      const reaction = ReactionEncoder.decode(this.idcode);
+      reaction.setFragment(this.fragment);
+
+      this.#editor.setReaction(reaction);
+    }
+
+    #handleChange = (editorEventOnChange) => {
+      const domEvent = new CustomEvent('change', {
+        detail: editorEventOnChange,
+      });
+      this.dispatchEvent(domEvent);
+    };
+
+    #destroyEditor() {
+      this.#editor.destroy();
+      this.#editor = undefined;
+    }
+
+    #resetEditor() {
+      this.#destroyEditor();
+      this.#initEditor();
+    }
+
+    /* --- lifecycle hooks --- */
+    /**
+     * Custom element added to page.
+     */
+    connectedCallback() {
+      this.attachShadow({ mode: 'open' });
+      this.shadowRoot.adoptedStyleSheets = [new CSSStyleSheet()];
+      this.#initEditor();
+    }
+
     /**
      * Custom element removed from page.
      */
-    // eslint-disable-next-line no-empty-function
-    disconnectedCallback() {}
+    disconnectedCallback() {
+      if (!this.#editor) return;
+      this.#editor.destroy();
+      this.#editor = undefined;
+    }
 
     /**
      * Custom element moved to new page.
@@ -69,8 +167,30 @@ function initCanvasEditorElement(CanvasEditor, Molecule) {
     /**
      * Attribute ${name} has changed from ${oldValue} to ${newValue}
      */
-    // eslint-disable-next-line no-unused-vars,no-empty-function
-    attributeChangedCallback(name, oldValue, newValue) {}
+    attributeChangedCallback(name, oldValue, newValue) {
+      switch (name) {
+        case 'idcode': {
+          this.idcode = newValue;
+          return void this.#initIdCode();
+        }
+        case 'fragment': {
+          this.fragment = newValue;
+          const molecule = this.#editor.getMolecule();
+          molecule.setFragment(this.fragment);
+          return void this.#editor.setMolecule(molecule);
+        }
+        case 'mode': {
+          this.mode = newValue;
+          return void this.#resetEditor();
+        }
+        case 'readonly': {
+          this.readonly = newValue;
+          return void this.#resetEditor();
+        }
+        default:
+          throw new Error('unsupported attribute change');
+      }
+    }
   }
 
   return CanvasEditorElement;
diff --git a/lib/canvas_editor/init/index.js b/lib/canvas_editor/init/index.js
index c655d79b..df802297 100644
--- a/lib/canvas_editor/init/index.js
+++ b/lib/canvas_editor/init/index.js
@@ -9,6 +9,7 @@ function init(OCL) {
     GenericEditorToolbar: JavaEditorToolbar,
     GenericUIHelper: JavaUIHelper,
     Molecule,
+    ReactionEncoder,
   } = OCL;
 
   const CanvasEditor = initCanvasEditor(
@@ -18,7 +19,11 @@ function init(OCL) {
   );
 
   function registerCustomElement() {
-    const CanvasEditorElement = initCanvasEditorElement(CanvasEditor, Molecule);
+    const CanvasEditorElement = initCanvasEditorElement(
+      CanvasEditor,
+      Molecule,
+      ReactionEncoder,
+    );
     customElements.define('openchemlib-editor', CanvasEditorElement);
   }