1 files changed, 171 insertions, 0 deletions
diff --git a/src/pdf_bridge.h b/src/pdf_bridge.h
new file mode 100644
index 00000000..85f477d0
--- /dev/null
+++ b/src/pdf_bridge.h
@@ -0,0 +1,171 @@
+#ifndef PARDES_PDF_BRIDGE_H
+#define PARDES_PDF_BRIDGE_H
+
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * MuPDF reports failures with setjmp/longjmp through fz_try/fz_catch. Those
+ * jumps must never cross Zig frames, so every operation that can throw lives
+ * behind this deliberately small C boundary.
+ */
+typedef struct pardes_pdf_document pardes_pdf_document;
+
+typedef struct pardes_pdf_pixmap {
+    void *handle;
+    const unsigned char *samples;
+    int width;
+    int height;
+    int stride;
+    int components;
+} pardes_pdf_pixmap;
+
+typedef struct pardes_pdf_text {
+    void *handle;
+    const unsigned char *data;
+    size_t len;
+} pardes_pdf_text;
+
+/*
+ * All geometry crossing this boundary is normalized to the cached page's
+ * bounds. (0,0) is the page's top-left and (1,1) its bottom-right, regardless
+ * of the DPI used for a particular render. Corner names retain MuPDF's quad
+ * orientation; callers must not collapse them to an axis-aligned rectangle.
+ */
+typedef struct pardes_pdf_point {
+    float x;
+    float y;
+} pardes_pdf_point;
+
+typedef struct pardes_pdf_quad {
+    pardes_pdf_point ul;
+    pardes_pdf_point ur;
+    pardes_pdf_point ll;
+    pardes_pdf_point lr;
+} pardes_pdf_quad;
+
+typedef enum pardes_pdf_highlight_kind {
+    PARDES_PDF_HIGHLIGHT_CUSTOM = 0,
+    PARDES_PDF_HIGHLIGHT_SEARCH = 1,
+    PARDES_PDF_HIGHLIGHT_SELECTION = 2
+} pardes_pdf_highlight_kind;
+
+typedef struct pardes_pdf_highlight {
+    pardes_pdf_quad quad;
+    unsigned char rgba[4];
+    int kind;
+} pardes_pdf_highlight;
+
+typedef struct pardes_pdf_search_quad {
+    pardes_pdf_quad quad;
+    size_t hit;
+} pardes_pdf_search_quad;
+
+typedef struct pardes_pdf_search_result {
+    void *handle;
+    const pardes_pdf_search_quad *quads;
+    size_t quad_count;
+    size_t hit_count;
+} pardes_pdf_search_result;
+
+typedef struct pardes_pdf_selection {
+    void *handle;
+    const pardes_pdf_quad *quads;
+    size_t quad_count;
+    pardes_pdf_point start;
+    pardes_pdf_point end;
+} pardes_pdf_selection;
+
+typedef struct pardes_pdf_owned_text {
+    void *handle;
+    const unsigned char *data;
+    size_t len;
+} pardes_pdf_owned_text;
+
+enum {
+    PARDES_PDF_OK = 0,
+    PARDES_PDF_ERROR = -1,
+    PARDES_PDF_LIMIT_EXCEEDED = -2,
+
+    /* Per-document MuPDF eviction cache; render buffers are separate. */
+    PARDES_PDF_STORE_LIMIT_BYTES = 64 * 1024 * 1024,
+
+    /*
+     * Search grows geometrically up to this aggregate count and then fails
+     * atomically with PARDES_PDF_LIMIT_EXCEEDED; it never returns a silently
+     * 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_document *pardes_pdf_open(const char *path, int *page_count);
+void pardes_pdf_close(pardes_pdf_document *document);
+
+int pardes_pdf_render(
+    pardes_pdf_document *document,
+    int page,
+    int max_dimension,
+    pardes_pdf_pixmap *out
+);
+
+int pardes_pdf_render_with_highlights(
+    pardes_pdf_document *document,
+    int page,
+    int max_dimension,
+    const pardes_pdf_highlight *highlights,
+    size_t highlight_count,
+    pardes_pdf_pixmap *out
+);
+void pardes_pdf_drop_pixmap(pardes_pdf_document *document, void *pixmap);
+
+int pardes_pdf_page_text(
+    pardes_pdf_document *document,
+    int page,
+    pardes_pdf_text *out
+);
+void pardes_pdf_drop_text(pardes_pdf_document *document, void *buffer);
+
+/* Case-insensitive, single-page search using MuPDF 1.27's iterative API. */
+int pardes_pdf_search_page(
+    pardes_pdf_document *document,
+    int page,
+    const char *needle,
+    pardes_pdf_search_result *out
+);
+void pardes_pdf_drop_search_result(pardes_pdf_document *document, void *result);
+
+/* Word-snap two normalized points and return oriented highlight quads. */
+int pardes_pdf_select(
+    pardes_pdf_document *document,
+    int page,
+    pardes_pdf_point start,
+    pardes_pdf_point end,
+    pardes_pdf_selection *out
+);
+void pardes_pdf_drop_selection(pardes_pdf_document *document, void *selection);
+
+/* Pure/no-throw oriented-quad hit test in normalized page space. */
+int pardes_pdf_point_inside_quad(
+    pardes_pdf_point point,
+    pardes_pdf_quad quad
+);
+
+/* The input endpoints are normally the snapped points returned above. */
+int pardes_pdf_copy_selection(
+    pardes_pdf_document *document,
+    int page,
+    pardes_pdf_point start,
+    pardes_pdf_point end,
+    pardes_pdf_owned_text *out
+);
+void pardes_pdf_drop_owned_text(pardes_pdf_document *document, void *text);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif