From 5e1ef01bc0639073f80a3d2fa5940c88303b7059 Mon Sep 17 00:00:00 2001
From: Cory McWilliams <cory@unprompted.com>
Date: Sun, 3 Dec 2023 18:03:42 +0000
Subject: [PATCH] Support pasting and showing images in the wiki.

git-svn-id: https://www.unprompted.com/svn/projects/tildefriends/trunk@4655 ed5197a5-7fde-0310-b194-c3ffbd925b24
---
 apps/wiki.json           |  2 +-
 apps/wiki/tf-wiki-doc.js | 85 +++++++++++++++++++++++++++++++++++++---
 2 files changed, 80 insertions(+), 7 deletions(-)

diff --git a/apps/wiki.json b/apps/wiki.json
index 232b897d..d717a556 100644
--- a/apps/wiki.json
+++ b/apps/wiki.json
@@ -1,5 +1,5 @@
 {
   "type": "tildefriends-app",
   "emoji": "📝",
-  "previous": "&r+JXDhWclHwMbeZHYjueOnSPaYCAXUlnl1Gyjgw6TxM=.sha256"
+  "previous": "&C6kk2ozHZKVTtxbEqLOD/xbsCjosnLb6HJWZuPZrtS8=.sha256"
 }
\ No newline at end of file
diff --git a/apps/wiki/tf-wiki-doc.js b/apps/wiki/tf-wiki-doc.js
index f5e0b106..265c2240 100644
--- a/apps/wiki/tf-wiki-doc.js
+++ b/apps/wiki/tf-wiki-doc.js
@@ -20,9 +20,9 @@ class TfWikiDocElement extends LitElement {
 	}
 
 	markdown(md) {
-		var reader = new commonmark.Parser({safe: true});
-		var writer = new commonmark.HtmlRenderer();
-		var parsed = reader.parse(md || '');
+		let reader = new commonmark.Parser({safe: true});
+		let writer = new commonmark.HtmlRenderer();
+		let parsed = reader.parse(md || '');
 		let walker = parsed.walker();
 		let event;
 		while ((event = walker.next())) {
@@ -33,6 +33,10 @@ class TfWikiDocElement extends LitElement {
 						node.destination.indexOf('/') == -1) {
 						node.destination = `#${this.wiki?.name}/${node.destination}`;
 					}
+				} else if (node.type == 'image') {
+					if (node.destination.startsWith('&')) {
+						node.destination = '/' + node.destination + '/view';
+					}
 				}
 			}
 		}
@@ -71,13 +75,12 @@ class TfWikiDocElement extends LitElement {
 			key: this.value.id,
 			parent: this.value.parent,
 			blob: id,
+			mentions: this.blob.match(/(&.{44}.sha256)/g)?.map(x => ({link: x})),
 		};
 		if (draft) {
 			message.recps = this.value.editors;
-			print(message);
 			message = await tfrpc.rpc.encrypt(this.whoami, this.value.editors, JSON.stringify(message));
 		}
-		print(message);
 		await tfrpc.rpc.appendMessage(this.whoami, message);
 		this.is_editing = false;
 	}
@@ -90,6 +93,74 @@ class TfWikiDocElement extends LitElement {
 		return this.append_message(false);
 	}
 
+	convert_to_format(buffer, type, mime_type) {
+		return new Promise(function(resolve, reject) {
+			let img = new Image();
+			img.onload = function() {
+				let canvas = document.createElement('canvas');
+				let width_scale = Math.min(img.width, 1024) / img.width;
+				let height_scale = Math.min(img.height, 1024) / img.height;
+				let scale = Math.min(width_scale, height_scale);
+				canvas.width = img.width * scale;
+				canvas.height = img.height * scale;
+				let context = canvas.getContext('2d');
+				context.drawImage(img, 0, 0, canvas.width, canvas.height);
+				let data_url = canvas.toDataURL(mime_type);
+				let result = atob(data_url.split(',')[1]).split('').map(x => x.charCodeAt(0));
+				resolve(result);
+			};
+			img.onerror = function(event) {
+				reject(new Error('Failed to load image.'));
+			};
+			let raw = Array.from(new Uint8Array(buffer)).map(b => String.fromCharCode(b)).join('');
+			let original = `data:${type};base64,${btoa(raw)}`;
+			img.src = original;
+		});
+	}
+
+	async add_file(editor, file) {
+		try {
+			let self = this;
+			let buffer = await file.arrayBuffer();
+			let type = file.type;
+			if (type.startsWith('image/')) {
+				let best_buffer;
+				let best_type;
+				for (let format of ['image/png', 'image/jpeg', 'image/webp']) {
+					let test_buffer = await self.convert_to_format(buffer, file.type, format);
+					if (!best_buffer || test_buffer.length < best_buffer.length) {
+						best_buffer = test_buffer;
+						best_type = format;
+					}
+				}
+				buffer = best_buffer;
+				type = best_type;
+			} else {
+				buffer = Array.from(new Uint8Array(buffer));
+			}
+			let id = await tfrpc.rpc.store_blob(buffer);
+			let name = type.split('/')[0] + ':' + file.name;
+			editor.value += `\n![${name}](${id})`;
+			self.on_edit({srcElement: editor});
+		} catch(e) {
+			alert(e?.message);
+		}
+	}
+
+	paste(event) {
+		let self = this;
+		for (let item of event.clipboardData.items) {
+			if (item.type?.startsWith('image/')) {
+				let file = item.getAsFile();
+				if (!file) {
+					continue;
+				}
+				self.add_file(event.srcElement, file);
+				break;
+			}
+		}
+	}
+
 	render() {
 		let value = JSON.stringify(this.value);
 		if (this.blob_for_value != value) {
@@ -110,7 +181,9 @@ class TfWikiDocElement extends LitElement {
 				<textarea
 					?hidden=${!this.is_editing}
 					style="flex: 1 1; min-height: 10em"
-					@input=${this.on_edit} .value=${this.blob ?? ''}></textarea>
+					@input=${this.on_edit}
+					@paste=${this.paste}
+					.value=${this.blob ?? ''}></textarea>
 				<div style="flex: 1 1">${unsafeHTML(this.markdown(this.blob))}</div>
 			</div>
 		`;