feat(latest): add chromedp browser fetcher for challenge-gated sites

backend/internal/latest/browser_test.go

@@ -0,0 +1,38 @@
+package latest
+
+import "testing"
+
+func TestKaganeAPIURL(t *testing.T) {
+	const uuid = "019f84bc-9ba0-7ed9-86f5-8b905ec7c28b"
+	tests := []struct {
+		name      string
+		seriesURL string
+		want      string
+		wantOK    bool
+	}{
+		{
+			name:      "series page maps to its API endpoint",
+			seriesURL: "https://kagane.to/series/" + uuid,
+			want:      "https://kagane.to/api/v2/series/" + uuid,
+			wantOK:    true,
+		},
+		{
+			name:      "trailing slash is tolerated",
+			seriesURL: "https://kagane.to/series/" + uuid + "/",
+			want:      "https://kagane.to/api/v2/series/" + uuid,
+			wantOK:    true,
+		},
+		{"not a series path", "https://kagane.to/search", "", false},
+		{"foreign host", "https://evil.example/series/" + uuid, "", false},
+		{"garbage", "://", "", false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, ok := kaganeAPIURL(tt.seriesURL)
+			if ok != tt.wantOK || got != tt.want {
+				t.Errorf("kaganeAPIURL(%q) = %q, %v; want %q, %v",
+					tt.seriesURL, got, ok, tt.want, tt.wantOK)
+			}
+		})
+	}
+}