Count link repetitions from the hash part, not the title

This fixes the case where different titles get the same hash. In the old
version, the repetition number was tracked with the title; since they
didn't match, the repetition number wasn't incremented.

Now, the repetition number is tracked from the hash (#title), so they
get the correct repetition.

Fixes #93

src/extension.ts

@@ -380,13 +380,7 @@ class MarkdownTocTools {
             title = title.replace(/\#/gi, "").trim();                // replace special char
             title = title.replace(/\b[_*]|[*_]\b/gi, "");            // replace bold and italic marks
 
-            if (!(title in hashMap)) {
-                hashMap[title] = 0;
-            } else {
-                hashMap[title] += 1;
-            }
-
-            let hash = this.getHash(title, this.options.ANCHOR_MODE, hashMap[title]);
+            let hash = this.getHash(title, this.options.ANCHOR_MODE, hashMap);
             headerList.push({
                 line : index,
                 depth : depth,
@@ -401,9 +395,39 @@ class MarkdownTocTools {
         return headerList;
     }
 
-    private getHash(headername : string, mode : string, repetition : number) {
-        let anchor = require('anchor-markdown-header');
-        return anchor(headername, mode, repetition);
+    private getHash(headername : string, mode : string, hashMap: { [key: string]: number }) {
+        // Get the link format for headername (force repetition = 0)
+        let link = require('anchor-markdown-header')(headername, mode, 0);
+
+        // Decompose the link into its two components
+        let match = link.match(/^\[([^\]]+)\]\((#[^)]+)\)$/);
+        if (!match || match.length < 3) return link;
+        let [title, hash] = match.slice(1, 3);
+
+        // Check if the hash is repeated
+        if (!(hash in hashMap)) {
+            hashMap[hash] = 0;
+        } else {
+            hashMap[hash] += 1;
+
+            // Add the repetition number to the hash
+            switch (mode) {
+            case "github.com":
+                hash = `${hash}-${hashMap[hash]}`;
+                break;
+            case "bitbucket.org":
+                hash = `${hash}_${hashMap[hash]}`;
+                break;
+            case "ghost.org":
+                hash = `${hash}-${hashMap[hash]}`;
+                break;
+            case "gitlab.com":
+                hash = `${hash}-${hashMap[hash]}`;
+                break;
+            }
+        }
+
+        return `[${title}](${hash})`;
     }
 
     private parseValidNumber(value : string) {