expose MuPDF PDF outline metadata

1 files changed, 59 insertions, 1 deletions

diff --git a/src/pdf_bridge.h b/src/pdf_bridge.h
index 17323a29..c85873e1 100644
--- a/src/pdf_bridge.h
+++ b/src/pdf_bridge.h
@@ -88,6 +88,46 @@ typedef struct pardes_pdf_owned_text {
     size_t len;
 } pardes_pdf_owned_text;
 
+typedef enum pardes_pdf_outline_destination_kind {
+    PARDES_PDF_OUTLINE_DESTINATION_NONE = 0,
+    PARDES_PDF_OUTLINE_DESTINATION_INTERNAL = 1,
+    PARDES_PDF_OUTLINE_DESTINATION_EXTERNAL = 2
+} pardes_pdf_outline_destination_kind;
+
+/*
+ * One pre-order depth-first row. Offsets address the result's byte arena;
+ * title_present distinguishes a missing title from a present empty title.
+ * Internal page numbers are zero-based. has_x/has_y preserve MuPDF's NAN
+ * sentinel for viewing coordinates that the outline destination omits.
+ */
+typedef struct pardes_pdf_outline_item {
+    size_t title_offset;
+    size_t title_len;
+    size_t uri_offset;
+    size_t uri_len;
+    unsigned int depth;
+    int page;
+    float x;
+    float y;
+    unsigned char title_present;
+    unsigned char has_x;
+    unsigned char has_y;
+    unsigned char is_open;
+    unsigned char flags;
+    unsigned char r;
+    unsigned char g;
+    unsigned char b;
+    int destination_kind;
+} pardes_pdf_outline_item;
+
+typedef struct pardes_pdf_outline_result {
+    void *handle;
+    const pardes_pdf_outline_item *items;
+    size_t item_count;
+    const unsigned char *bytes;
+    size_t bytes_len;
+} pardes_pdf_outline_result;
+
 enum {
     PARDES_PDF_OK = 0,
     PARDES_PDF_ERROR = -1,
@@ -102,7 +142,12 @@ enum {
      * truncated result. Selection uses one extra private probe slot so an
      * exact-at-the-limit result remains distinguishable from truncation.
      */
-    PARDES_PDF_MAX_RESULT_QUADS = 65536
+    PARDES_PDF_MAX_RESULT_QUADS = 65536,
+
+    /* Outline conversion is atomic: crossing any bound returns no rows. */
+    PARDES_PDF_MAX_OUTLINE_ITEMS = 4096,
+    PARDES_PDF_MAX_OUTLINE_DEPTH = 64,
+    PARDES_PDF_MAX_OUTLINE_BYTES = 4 * 1024 * 1024
 };
 
 pardes_pdf_document *pardes_pdf_open(const char *path, int *page_count);
@@ -194,6 +239,19 @@ int pardes_pdf_copy_selection(
 );
 void pardes_pdf_drop_owned_text(pardes_pdf_document *document, void *text);
 
+/*
+ * Flatten fz_load_outline's tree in stable document-order DFS. The borrowed
+ * table and byte arena remain valid until drop_outline_result.
+ */
+int pardes_pdf_load_outline(
+    pardes_pdf_document *document,
+    pardes_pdf_outline_result *out
+);
+void pardes_pdf_drop_outline_result(
+    pardes_pdf_document *document,
+    void *outline
+);
+
 #ifdef __cplusplus
 }
 #endif