From 77cb65439fcd0d192666f73c8dcf50484f21aaff Mon Sep 17 00:00:00 2001
From: Yiyi Wang <shd101wyy@sina.com>
Date: Tue, 20 Jun 2017 08:33:39 -0500
Subject: [PATCH] better tag a click event.

---
 src/extension.ts                         | 16 ++++++++++++++++
 src/markdown-preview-enhanced-webview.ts | 23 +++++++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/src/extension.ts b/src/extension.ts
index 708c0d6..496dad5 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -232,6 +232,20 @@ export function activate(context: vscode.ExtensionContext) {
 				type: 'run-code-chunk'
 			})
 	}
+
+	function clickTagA(uri, href) {
+		const sourceUri = vscode.Uri.parse(decodeURIComponent(uri));
+		if (['.pdf', '.xls', '.xlsx', '.doc', '.ppt', '.docx', '.pptx'].indexOf(path.extname(href)) >= 0) {
+			utility.openFile(href)
+		} else if (href.match(/^file\:\/\/\//)) {
+			// openFilePath = href.slice(8) # remove protocal
+			let openFilePath = href.replace(/(\s*)[\#\?](.+)$/, '') // remove #anchor and ?params...
+			openFilePath = decodeURI(openFilePath)
+		  vscode.commands.executeCommand('vscode.open', vscode.Uri.parse(openFilePath), vscode.ViewColumn.One)
+		} else {
+			utility.openFile(href)
+		}
+	}
 	
 
 	context.subscriptions.push(vscode.workspace.onDidSaveTextDocument(document => {
@@ -364,6 +378,8 @@ export function activate(context: vscode.ExtensionContext) {
 
 	context.subscriptions.push(vscode.commands.registerCommand('_markdown-preview-enhanced.runAllCodeChunks', runAllCodeChunks))
 
+	context.subscriptions.push(vscode.commands.registerCommand('_markdown-preview-enhanced.clickTagA', clickTagA))
+
   context.subscriptions.push(contentProviderRegistration)
 }
 
diff --git a/src/markdown-preview-enhanced-webview.ts b/src/markdown-preview-enhanced-webview.ts
index ae9fdaf..b35d1de 100644
--- a/src/markdown-preview-enhanced-webview.ts
+++ b/src/markdown-preview-enhanced-webview.ts
@@ -667,6 +667,27 @@ async function initEvents() {
   mpe.refreshingIcon.style.display = "none"
 }
 
+function bindTagAClickEvent() {
+  const as = mpe.previewElement.getElementsByTagName('a')
+  for (let i = 0; i < as.length; i++) {
+    const a = as[i]
+    const href =  a.getAttribute('href')
+    if (href && href[0] === '#') {
+      // anchor, do nothing 
+    } else {
+      a.onclick = (event)=> {
+        event.preventDefault()
+        event.stopPropagation()
+
+        window.parent.postMessage({ 
+          command: 'did-click-link', // <= this has to be `did-click-link` to post message
+          data: `command:_markdown-preview-enhanced.clickTagA?${JSON.stringify([sourceUri, href])}`
+        }, 'file://')
+      }
+    }
+  }
+}
+
 /**
  * update previewElement innerHTML content
  * @param html 
@@ -695,6 +716,8 @@ function updateHTML(html) {
   // init several events 
   initEvents().then(()=> {
     mpe.scrollMap = null 
+
+    bindTagAClickEvent()
     
     // scroll to initial position 
     if (!mpe.doneLoadingPreview) {