Fix gist preview detection (on custom hostname) to use query string instead of hardcoded hostnames

src/claude_code_transcripts/__init__.py

@@ -1141,14 +1141,13 @@ def render_message(log_type, message_json, timestamp):
 });
 """
 
-# JavaScript to fix relative URLs when served via gisthost.github.io or gistpreview.github.io
-# Fixes issue #26: Pagination links broken on gisthost.github.io
+# JavaScript to fix relative URLs when served via gist preview hosts.
+# Detects gist preview context by the URL query string pattern ?<hex-gist-id>/...
+# Fixes issue #26: Pagination links broken on gist preview hosts
 GIST_PREVIEW_JS = r"""
 (function() {
-    var hostname = window.location.hostname;
-    if (hostname !== 'gisthost.github.io' && hostname !== 'gistpreview.github.io') return;
-    // URL format: https://gisthost.github.io/?GIST_ID/filename.html
-    var match = window.location.search.match(/^\?([^/]+)/);
+    // Detect gist preview context by query string pattern: ?<hex-gist-id>/...
+    var match = window.location.search.match(/^\?([a-f0-9]{20,})(\/|$)/i);
     if (!match) return;
     var gistId = match[1];
 
@@ -1176,7 +1175,7 @@ def render_message(log_type, message_json, timestamp):
     }
 
     // Use MutationObserver to catch dynamically added content
-    // gistpreview.github.io may add content after initial load
+    // Gist preview hosts may add content after initial load
     var observer = new MutationObserver(function(mutations) {
         mutations.forEach(function(mutation) {
             mutation.addedNodes.forEach(function(node) {
@@ -1209,7 +1208,7 @@ def render_message(log_type, message_json, timestamp):
     startObserving();
 
     // Handle fragment navigation after dynamic content loads
-    // gisthost.github.io/gistpreview.github.io loads content dynamically, so the browser's
+    // Gist preview hosts load content dynamically, so the browser's
     // native fragment navigation fails because the element doesn't exist yet
     function scrollToFragment() {
         var hash = window.location.hash;

src/claude_code_transcripts/templates/search.js

@@ -18,21 +18,13 @@
     // Show search box (progressive enhancement)
     searchBox.style.display = 'flex';
 
-    // Gist preview support - detect if we're on gisthost.github.io or gistpreview.github.io
-    var hostname = window.location.hostname;
-    var isGistPreview = hostname === 'gisthost.github.io' || hostname === 'gistpreview.github.io';
-    var gistId = null;
+    // Gist preview support - detect by query string pattern: ?<hex-gist-id>/...
+    var gistMatch = window.location.search.match(/^\?([a-f0-9]{20,})(\/|$)/i);
+    var isGistPreview = !!gistMatch;
+    var gistId = gistMatch ? gistMatch[1] : null;
     var gistOwner = null;
     var gistInfoLoaded = false;
 
-    if (isGistPreview) {
-        // Extract gist ID from URL query string like ?78a436a8a9e7a2e603738b8193b95410/index.html
-        var queryMatch = window.location.search.match(/^\?([a-f0-9]+)/i);
-        if (queryMatch) {
-            gistId = queryMatch[1];
-        }
-    }
-
     async function loadGistInfo() {
         if (!isGistPreview || !gistId || gistInfoLoaded) return;
         try {

tests/__snapshots__/test_generate_html/TestGenerateHtml.test_generates_index_html.html

@@ -221,21 +221,13 @@ <h1>Claude Code transcript</h1>
     // Show search box (progressive enhancement)
     searchBox.style.display = 'flex';
 
-    // Gist preview support - detect if we're on gisthost.github.io or gistpreview.github.io
-    var hostname = window.location.hostname;
-    var isGistPreview = hostname === 'gisthost.github.io' || hostname === 'gistpreview.github.io';
-    var gistId = null;
+    // Gist preview support - detect by query string pattern: ?<hex-gist-id>/...
+    var gistMatch = window.location.search.match(/^\?([a-f0-9]{20,})(\/|$)/i);
+    var isGistPreview = !!gistMatch;
+    var gistId = gistMatch ? gistMatch[1] : null;
     var gistOwner = null;
     var gistInfoLoaded = false;
 
-    if (isGistPreview) {
-        // Extract gist ID from URL query string like ?78a436a8a9e7a2e603738b8193b95410/index.html
-        var queryMatch = window.location.search.match(/^\?([a-f0-9]+)/i);
-        if (queryMatch) {
-            gistId = queryMatch[1];
-        }
-    }
-
     async function loadGistInfo() {
         if (!isGistPreview || !gistId || gistInfoLoaded) return;
         try {

tests/__snapshots__/test_generate_html/TestParseSessionFile.test_jsonl_generates_html.html

@@ -212,21 +212,13 @@ <h1>Claude Code transcript</h1>
     // Show search box (progressive enhancement)
     searchBox.style.display = 'flex';
 
-    // Gist preview support - detect if we're on gisthost.github.io or gistpreview.github.io
-    var hostname = window.location.hostname;
-    var isGistPreview = hostname === 'gisthost.github.io' || hostname === 'gistpreview.github.io';
-    var gistId = null;
+    // Gist preview support - detect by query string pattern: ?<hex-gist-id>/...
+    var gistMatch = window.location.search.match(/^\?([a-f0-9]{20,})(\/|$)/i);
+    var isGistPreview = !!gistMatch;
+    var gistId = gistMatch ? gistMatch[1] : null;
     var gistOwner = null;
     var gistInfoLoaded = false;
 
-    if (isGistPreview) {
-        // Extract gist ID from URL query string like ?78a436a8a9e7a2e603738b8193b95410/index.html
-        var queryMatch = window.location.search.match(/^\?([a-f0-9]+)/i);
-        if (queryMatch) {
-            gistId = queryMatch[1];
-        }
-    }
-
     async function loadGistInfo() {
         if (!isGistPreview || !gistId || gistInfoLoaded) return;
         try {

tests/test_generate_html.py

@@ -567,6 +567,41 @@ def test_gist_preview_js_runs_on_dom_content_loaded(self):
         # The JS should listen for DOMContentLoaded
         assert "DOMContentLoaded" in GIST_PREVIEW_JS
 
+    def test_gist_preview_js_detects_by_query_string_not_hostname(self):
+        """Test that GIST_PREVIEW_JS detects gist preview context using the URL
+        query string pattern (?<hex-gist-id>/...) instead of hardcoded hostnames.
+
+        This allows it to work on any gist preview host, not just
+        gisthost.github.io and gistpreview.github.io.
+        """
+        # Should NOT contain hardcoded hostname checks
+        assert "gisthost.github.io" not in GIST_PREVIEW_JS
+        assert "gistpreview.github.io" not in GIST_PREVIEW_JS
+        # Should use a regex on location.search to detect gist preview context
+        assert "location.search" in GIST_PREVIEW_JS
+
+
+class TestSearchJsGistDetection:
+    """Tests for gist preview detection in search.js template."""
+
+    @pytest.fixture
+    def search_js_content(self):
+        search_js_path = (
+            Path(__file__).parent.parent
+            / "src"
+            / "claude_code_transcripts"
+            / "templates"
+            / "search.js"
+        )
+        return search_js_path.read_text(encoding="utf-8")
+
+    def test_search_js_detects_by_query_string_not_hostname(self, search_js_content):
+        """Test that search.js detects gist preview context using the URL
+        query string pattern instead of hardcoded hostnames."""
+        assert "gisthost.github.io" not in search_js_content
+        assert "gistpreview.github.io" not in search_js_content
+        assert "location.search" in search_js_content
+
 
 class TestCreateGist:
     """Tests for the create_gist function."""
@@ -728,9 +763,9 @@ def mock_run(*args, **kwargs):
 
         assert result.exit_code == 0
         assert (output_dir / "index.html").exists()
-        # Verify JS was injected (checks for both domains for backwards compatibility)
+        # Verify gist preview JS was injected
         index_content = (output_dir / "index.html").read_text(encoding="utf-8")
-        assert "gisthost.github.io" in index_content
+        assert "location.search" in index_content
 
 
 class TestContinuationLongTexts: