From 32fd1eb318c81b5b0b5c1e68a1f2a929ebb0d20c Mon Sep 17 00:00:00 2001
From: RMidhunSuresh <rmidhunsuresh@gmail.com>
Date: Sat, 8 May 2021 19:17:43 +0530
Subject: [PATCH] Implement linkifier

Signed-off-by: RMidhunSuresh <rmidhunsuresh@gmail.com>
---
 src/domain/Linkifier.js | 57 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 src/domain/Linkifier.js

diff --git a/src/domain/Linkifier.js b/src/domain/Linkifier.js
new file mode 100644
index 00000000..a429c8d3
--- /dev/null
+++ b/src/domain/Linkifier.js
@@ -0,0 +1,57 @@
+import { MessageObjectFormat } from "./MessageObjectFormat.js";
+
+export class Linkifier {
+
+    /**
+     * @param {String} text Text to linkify
+     */
+    constructor(text) {
+        this._text = text;
+        this._curr = 0;
+        this._message = new MessageObjectFormat();
+    }
+
+    /**
+     * Separate string into text, newlines and add them into message object.
+     * @param {String} text 
+     */
+    _addTextToMessage(text) {
+        const components = text.split("\n");
+        components.slice(0, -1).forEach(t => {
+            this._message.insertText(t);
+            this._message.insertNewline();
+        });
+        const [last] = components.slice(-1);
+        this._message.insertText(last);
+    }
+
+    /**
+     * Add text from this._curr upto start of supplied match into message object.
+     * If match is not provided, everything from this._curr to the end of 
+     * this._text is added as text to the message object.
+     * @param {Array} [match] regex match 
+     */
+    _handleText(match) {
+        const index = match?.index;
+        const text = this._text.slice(this._curr, index);
+        this._addTextToMessage(text);
+        const len = match?.[0].length;
+        this._curr = index + len;
+    }
+
+    /**
+     * Splits message text into parts (text, newline and links)
+     * @returns {MessageObjectFormat} Object representation of chat message
+     */
+    linkify() {
+        const regex = /(?:https|http|ftp):\/\/[a-zA-Z0-9:.\[\]#-]+(?:\/[^\s]*[^\s.,?!]|[^\s\u{80}-\u{10ffff}.,?!])/gui
+        const matches = this._text.matchAll(regex);
+        for (let match of matches) {
+            const link = match[0];
+            this._handleText(match);
+            this._message.insertLink(link, link);
+        }
+        this._handleText();
+        return this._message;
+    }
+}