--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/include/mupdf/pdf/form.h	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,381 @@
+// Copyright (C) 2004-2025 Artifex Software, Inc.
+//
+// This file is part of MuPDF.
+//
+// MuPDF is free software: you can redistribute it and/or modify it under the
+// terms of the GNU Affero General Public License as published by the Free
+// Software Foundation, either version 3 of the License, or (at your option)
+// any later version.
+//
+// MuPDF is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
+// details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with MuPDF. If not, see <https://www.gnu.org/licenses/agpl-3.0.en.html>
+//
+// Alternative licensing terms are available from the licensor.
+// For commercial licensing, see <https://www.artifex.com/> or contact
+// Artifex Software, Inc., 39 Mesa Street, Suite 108A, San Francisco,
+// CA 94129, USA, for further information.
+
+#ifndef MUPDF_PDF_FORM_H
+#define MUPDF_PDF_FORM_H
+
+#include "mupdf/fitz/display-list.h"
+#include "mupdf/pdf/document.h"
+
+/* Types of widget */
+enum pdf_widget_type
+{
+	PDF_WIDGET_TYPE_UNKNOWN,
+	PDF_WIDGET_TYPE_BUTTON,
+	PDF_WIDGET_TYPE_CHECKBOX,
+	PDF_WIDGET_TYPE_COMBOBOX,
+	PDF_WIDGET_TYPE_LISTBOX,
+	PDF_WIDGET_TYPE_RADIOBUTTON,
+	PDF_WIDGET_TYPE_SIGNATURE,
+	PDF_WIDGET_TYPE_TEXT,
+};
+
+/* Types of text widget content */
+enum pdf_widget_tx_format
+{
+	PDF_WIDGET_TX_FORMAT_NONE,
+	PDF_WIDGET_TX_FORMAT_NUMBER,
+	PDF_WIDGET_TX_FORMAT_SPECIAL,
+	PDF_WIDGET_TX_FORMAT_DATE,
+	PDF_WIDGET_TX_FORMAT_TIME
+};
+
+pdf_annot *pdf_keep_widget(fz_context *ctx, pdf_annot *widget);
+void pdf_drop_widget(fz_context *ctx, pdf_annot *widget);
+pdf_annot *pdf_first_widget(fz_context *ctx, pdf_page *page);
+pdf_annot *pdf_next_widget(fz_context *ctx, pdf_annot *previous);
+int pdf_update_widget(fz_context *ctx, pdf_annot *widget);
+
+/*
+	create a new signature widget on the specified page, with the
+	specified name.
+
+	The returns pdf_annot reference must be dropped by the caller.
+	This is a change from releases up to an including 1.18, where
+	the returned reference was owned by the page and did not need
+	to be freed by the caller.
+*/
+pdf_annot *pdf_create_signature_widget(fz_context *ctx, pdf_page *page, char *name);
+
+enum pdf_widget_type pdf_widget_type(fz_context *ctx, pdf_annot *widget);
+
+fz_rect pdf_bound_widget(fz_context *ctx, pdf_annot *widget);
+
+/*
+	get the maximum number of
+	characters permitted in a text widget
+*/
+int pdf_text_widget_max_len(fz_context *ctx, pdf_annot *tw);
+
+/*
+	get the type of content
+	required by a text widget
+*/
+int pdf_text_widget_format(fz_context *ctx, pdf_annot *tw);
+
+/*
+	get the list of options for a list box or combo box.
+
+	Returns the number of options and fills in their
+	names within the supplied array. Should first be called with a
+	NULL array to find out how big the array should be.  If exportval
+	is true, then the export values will be returned and not the list
+	values if there are export values present.
+*/
+int pdf_choice_widget_options(fz_context *ctx, pdf_annot *tw, int exportval, const char *opts[]);
+int pdf_choice_widget_is_multiselect(fz_context *ctx, pdf_annot *tw);
+
+/*
+	get the value of a choice widget.
+
+	Returns the number of options currently selected and fills in
+	the supplied array with their strings. Should first be called
+	with NULL as the array to find out how big the array need to
+	be. The filled in elements should not be freed by the caller.
+*/
+int pdf_choice_widget_value(fz_context *ctx, pdf_annot *tw, const char *opts[]);
+
+/*
+	set the value of a choice widget.
+
+	The caller should pass the number of options selected and an
+	array of their names
+*/
+void pdf_choice_widget_set_value(fz_context *ctx, pdf_annot *tw, int n, const char *opts[]);
+
+int pdf_choice_field_option_count(fz_context *ctx, pdf_obj *field);
+const char *pdf_choice_field_option(fz_context *ctx, pdf_obj *field, int exportval, int i);
+
+int pdf_widget_is_signed(fz_context *ctx, pdf_annot *widget);
+int pdf_widget_is_readonly(fz_context *ctx, pdf_annot *widget);
+
+/* Field flags */
+enum
+{
+	/* All fields */
+	PDF_FIELD_IS_READ_ONLY = 1,
+	PDF_FIELD_IS_REQUIRED = 1 << 1,
+	PDF_FIELD_IS_NO_EXPORT = 1 << 2,
+
+	/* Text fields */
+	PDF_TX_FIELD_IS_MULTILINE = 1 << 12,
+	PDF_TX_FIELD_IS_PASSWORD = 1 << 13,
+	PDF_TX_FIELD_IS_FILE_SELECT = 1 << 20,
+	PDF_TX_FIELD_IS_DO_NOT_SPELL_CHECK = 1 << 22,
+	PDF_TX_FIELD_IS_DO_NOT_SCROLL = 1 << 23,
+	PDF_TX_FIELD_IS_COMB = 1 << 24,
+	PDF_TX_FIELD_IS_RICH_TEXT = 1 << 25,
+
+	/* Button fields */
+	PDF_BTN_FIELD_IS_NO_TOGGLE_TO_OFF = 1 << 14,
+	PDF_BTN_FIELD_IS_RADIO = 1 << 15,
+	PDF_BTN_FIELD_IS_PUSHBUTTON = 1 << 16,
+	PDF_BTN_FIELD_IS_RADIOS_IN_UNISON = 1 << 25,
+
+	/* Choice fields */
+	PDF_CH_FIELD_IS_COMBO = 1 << 17,
+	PDF_CH_FIELD_IS_EDIT = 1 << 18,
+	PDF_CH_FIELD_IS_SORT = 1 << 19,
+	PDF_CH_FIELD_IS_MULTI_SELECT = 1 << 21,
+	PDF_CH_FIELD_IS_DO_NOT_SPELL_CHECK = 1 << 22,
+	PDF_CH_FIELD_IS_COMMIT_ON_SEL_CHANGE = 1 << 25,
+};
+
+void pdf_calculate_form(fz_context *ctx, pdf_document *doc);
+void pdf_reset_form(fz_context *ctx, pdf_document *doc, pdf_obj *fields, int exclude);
+
+int pdf_field_type(fz_context *ctx, pdf_obj *field);
+const char *pdf_field_type_string(fz_context *ctx, pdf_obj *field);
+int pdf_field_flags(fz_context *ctx, pdf_obj *field);
+
+/*
+	Retrieve the name for a field as a C string that
+	must be freed by the caller.
+*/
+char *pdf_load_field_name(fz_context *ctx, pdf_obj *field);
+const char *pdf_field_value(fz_context *ctx, pdf_obj *field);
+void pdf_create_field_name(fz_context *ctx, pdf_document *doc, const char *prefix, char *buf, size_t len);
+
+char *pdf_field_border_style(fz_context *ctx, pdf_obj *field);
+void pdf_field_set_border_style(fz_context *ctx, pdf_obj *field, const char *text);
+void pdf_field_set_button_caption(fz_context *ctx, pdf_obj *field, const char *text);
+void pdf_field_set_fill_color(fz_context *ctx, pdf_obj *field, pdf_obj *col);
+void pdf_field_set_text_color(fz_context *ctx, pdf_obj *field, pdf_obj *col);
+int pdf_field_display(fz_context *ctx, pdf_obj *field);
+void pdf_field_set_display(fz_context *ctx, pdf_obj *field, int d);
+const char *pdf_field_label(fz_context *ctx, pdf_obj *field);
+pdf_obj *pdf_button_field_on_state(fz_context *ctx, pdf_obj *field);
+
+int pdf_set_field_value(fz_context *ctx, pdf_document *doc, pdf_obj *field, const char *text, int ignore_trigger_events);
+
+/*
+	Update the text of a text widget.
+
+	The text is first validated by the Field/Keystroke event processing and accepted only if it passes.
+
+	The function returns whether validation passed.
+*/
+int pdf_set_text_field_value(fz_context *ctx, pdf_annot *widget, const char *value);
+int pdf_set_choice_field_value(fz_context *ctx, pdf_annot *widget, const char *value);
+int pdf_edit_text_field_value(fz_context *ctx, pdf_annot *widget, const char *value, const char *change, int *selStart, int *selEnd, char **newvalue);
+
+typedef struct
+{
+	char *cn;
+	char *o;
+	char *ou;
+	char *email;
+	char *c;
+}
+pdf_pkcs7_distinguished_name;
+
+typedef enum
+{
+	PDF_SIGNATURE_ERROR_OKAY,
+	PDF_SIGNATURE_ERROR_NO_SIGNATURES,
+	PDF_SIGNATURE_ERROR_NO_CERTIFICATE,
+	PDF_SIGNATURE_ERROR_DIGEST_FAILURE,
+	PDF_SIGNATURE_ERROR_SELF_SIGNED,
+	PDF_SIGNATURE_ERROR_SELF_SIGNED_IN_CHAIN,
+	PDF_SIGNATURE_ERROR_NOT_TRUSTED,
+	PDF_SIGNATURE_ERROR_NOT_SIGNED,
+	PDF_SIGNATURE_ERROR_UNKNOWN,
+} pdf_signature_error;
+
+/* Increment the reference count for a signer object */
+typedef pdf_pkcs7_signer *(pdf_pkcs7_keep_signer_fn)(fz_context *ctx, pdf_pkcs7_signer *signer);
+
+/* Drop a reference for a signer object */
+typedef void (pdf_pkcs7_drop_signer_fn)(fz_context *ctx, pdf_pkcs7_signer *signer);
+
+/* Obtain the distinguished name information from a signer object */
+typedef pdf_pkcs7_distinguished_name *(pdf_pkcs7_get_signing_name_fn)(fz_context *ctx, pdf_pkcs7_signer *signer);
+
+/* Predict the size of the digest. The actual digest returned by create_digest will be no greater in size */
+typedef size_t (pdf_pkcs7_max_digest_size_fn)(fz_context *ctx, pdf_pkcs7_signer *signer);
+
+/* Create a signature based on ranges of bytes drawn from a stream */
+typedef int (pdf_pkcs7_create_digest_fn)(fz_context *ctx, pdf_pkcs7_signer *signer, fz_stream *in, unsigned char *digest, size_t digest_len);
+
+struct pdf_pkcs7_signer
+{
+	pdf_pkcs7_keep_signer_fn *keep;
+	pdf_pkcs7_drop_signer_fn *drop;
+	pdf_pkcs7_get_signing_name_fn *get_signing_name;
+	pdf_pkcs7_max_digest_size_fn *max_digest_size;
+	pdf_pkcs7_create_digest_fn *create_digest;
+};
+
+typedef struct pdf_pkcs7_verifier pdf_pkcs7_verifier;
+
+typedef void (pdf_pkcs7_drop_verifier_fn)(fz_context *ctx, pdf_pkcs7_verifier *verifier);
+typedef pdf_signature_error (pdf_pkcs7_check_certificate_fn)(fz_context *ctx, pdf_pkcs7_verifier *verifier, unsigned char *signature, size_t len);
+typedef pdf_signature_error (pdf_pkcs7_check_digest_fn)(fz_context *ctx, pdf_pkcs7_verifier *verifier, fz_stream *in, unsigned char *signature, size_t len);
+typedef pdf_pkcs7_distinguished_name *(pdf_pkcs7_get_signatory_fn)(fz_context *ctx, pdf_pkcs7_verifier *verifier, unsigned char *signature, size_t len);
+
+struct pdf_pkcs7_verifier
+{
+	pdf_pkcs7_drop_verifier_fn *drop;
+	pdf_pkcs7_check_certificate_fn *check_certificate;
+	pdf_pkcs7_check_digest_fn *check_digest;
+	pdf_pkcs7_get_signatory_fn *get_signatory;
+};
+
+int pdf_signature_is_signed(fz_context *ctx, pdf_document *doc, pdf_obj *field);
+void pdf_signature_set_value(fz_context *ctx, pdf_document *doc, pdf_obj *field, pdf_pkcs7_signer *signer, int64_t stime);
+
+int pdf_count_signatures(fz_context *ctx, pdf_document *doc);
+
+char *pdf_signature_error_description(pdf_signature_error err);
+
+pdf_pkcs7_distinguished_name *pdf_signature_get_signatory(fz_context *ctx, pdf_pkcs7_verifier *verifier, pdf_document *doc, pdf_obj *signature);
+pdf_pkcs7_distinguished_name *pdf_signature_get_widget_signatory(fz_context *ctx, pdf_pkcs7_verifier *verifier, pdf_annot *widget);
+void pdf_signature_drop_distinguished_name(fz_context *ctx, pdf_pkcs7_distinguished_name *name);
+char *pdf_signature_format_distinguished_name(fz_context *ctx, pdf_pkcs7_distinguished_name *name);
+char *pdf_signature_info(fz_context *ctx, const char *name, pdf_pkcs7_distinguished_name *dn, const char *reason, const char *location, int64_t date, int include_labels);
+fz_display_list *pdf_signature_appearance_signed(fz_context *ctx, fz_rect rect, fz_text_language lang, fz_image *img, const char *left_text, const char *right_text, int include_logo);
+fz_display_list *pdf_signature_appearance_unsigned(fz_context *ctx, fz_rect rect, fz_text_language lang);
+
+pdf_signature_error pdf_check_digest(fz_context *ctx, pdf_pkcs7_verifier *verifier, pdf_document *doc, pdf_obj *signature);
+pdf_signature_error pdf_check_certificate(fz_context *ctx, pdf_pkcs7_verifier *verifier, pdf_document *doc, pdf_obj *signature);
+pdf_signature_error pdf_check_widget_digest(fz_context *ctx, pdf_pkcs7_verifier *verifier, pdf_annot *widget);
+pdf_signature_error pdf_check_widget_certificate(fz_context *ctx, pdf_pkcs7_verifier *verifier, pdf_annot *widget);
+
+void pdf_clear_signature(fz_context *ctx, pdf_annot *widget);
+
+/*
+	Sign a signature field, while assigning it an arbitrary appearance determined by a display list.
+	The function pdf_signature_appearance can generate a variety of common signature appearances.
+*/
+void pdf_sign_signature_with_appearance(fz_context *ctx, pdf_annot *widget, pdf_pkcs7_signer *signer, int64_t date, fz_display_list *disp_list);
+
+enum {
+	PDF_SIGNATURE_SHOW_LABELS = 1,
+	PDF_SIGNATURE_SHOW_DN = 2,
+	PDF_SIGNATURE_SHOW_DATE = 4,
+	PDF_SIGNATURE_SHOW_TEXT_NAME = 8,
+	PDF_SIGNATURE_SHOW_GRAPHIC_NAME = 16,
+	PDF_SIGNATURE_SHOW_LOGO = 32,
+};
+
+#define PDF_SIGNATURE_DEFAULT_APPEARANCE ( \
+	PDF_SIGNATURE_SHOW_LABELS | \
+	PDF_SIGNATURE_SHOW_DN | \
+	PDF_SIGNATURE_SHOW_DATE | \
+	PDF_SIGNATURE_SHOW_TEXT_NAME | \
+	PDF_SIGNATURE_SHOW_GRAPHIC_NAME | \
+	PDF_SIGNATURE_SHOW_LOGO )
+
+/*
+	Sign a signature field, while assigning it a default appearance.
+*/
+void pdf_sign_signature(fz_context *ctx, pdf_annot *widget,
+	pdf_pkcs7_signer *signer,
+	int appearance_flags,
+	fz_image *graphic,
+	const char *reason,
+	const char *location);
+
+/*
+	Create a preview of the default signature appearance.
+*/
+fz_display_list *pdf_preview_signature_as_display_list(fz_context *ctx,
+	float w, float h, fz_text_language lang,
+	pdf_pkcs7_signer *signer,
+	int appearance_flags,
+	fz_image *graphic,
+	const char *reason,
+	const char *location);
+
+fz_pixmap *pdf_preview_signature_as_pixmap(fz_context *ctx,
+	int w, int h, fz_text_language lang,
+	pdf_pkcs7_signer *signer,
+	int appearance_flags,
+	fz_image *graphic,
+	const char *reason,
+	const char *location);
+
+void pdf_drop_signer(fz_context *ctx, pdf_pkcs7_signer *signer);
+void pdf_drop_verifier(fz_context *ctx, pdf_pkcs7_verifier *verifier);
+
+void pdf_field_reset(fz_context *ctx, pdf_document *doc, pdf_obj *field);
+
+pdf_obj *pdf_lookup_field(fz_context *ctx, pdf_obj *form, const char *name);
+
+/* Form text field editing events: */
+
+typedef struct
+{
+	const char *value;
+	const char *change;
+	int selStart, selEnd;
+	int willCommit;
+	char *newChange;
+	char *newValue;
+} pdf_keystroke_event;
+
+int pdf_field_event_keystroke(fz_context *ctx, pdf_document *doc, pdf_obj *field, pdf_keystroke_event *evt);
+int pdf_field_event_validate(fz_context *ctx, pdf_document *doc, pdf_obj *field, const char *value, char **newvalue);
+void pdf_field_event_calculate(fz_context *ctx, pdf_document *doc, pdf_obj *field);
+char *pdf_field_event_format(fz_context *ctx, pdf_document *doc, pdf_obj *field);
+
+int pdf_annot_field_event_keystroke(fz_context *ctx, pdf_document *doc, pdf_annot *annot, pdf_keystroke_event *evt);
+
+/* Call these to trigger actions from various UI events: */
+
+void pdf_document_event_will_close(fz_context *ctx, pdf_document *doc);
+void pdf_document_event_will_save(fz_context *ctx, pdf_document *doc);
+void pdf_document_event_did_save(fz_context *ctx, pdf_document *doc);
+void pdf_document_event_will_print(fz_context *ctx, pdf_document *doc);
+void pdf_document_event_did_print(fz_context *ctx, pdf_document *doc);
+
+void pdf_page_event_open(fz_context *ctx, pdf_page *page);
+void pdf_page_event_close(fz_context *ctx, pdf_page *page);
+
+void pdf_annot_event_enter(fz_context *ctx, pdf_annot *annot);
+void pdf_annot_event_exit(fz_context *ctx, pdf_annot *annot);
+void pdf_annot_event_down(fz_context *ctx, pdf_annot *annot);
+void pdf_annot_event_up(fz_context *ctx, pdf_annot *annot);
+void pdf_annot_event_focus(fz_context *ctx, pdf_annot *annot);
+void pdf_annot_event_blur(fz_context *ctx, pdf_annot *annot);
+void pdf_annot_event_page_open(fz_context *ctx, pdf_annot *annot);
+void pdf_annot_event_page_close(fz_context *ctx, pdf_annot *annot);
+void pdf_annot_event_page_visible(fz_context *ctx, pdf_annot *annot);
+void pdf_annot_event_page_invisible(fz_context *ctx, pdf_annot *annot);
+
+/*
+ * Bake appearances of annotations and/or widgets into static page content,
+ * and remove the corresponding interactive PDF objects.
+ */
+void pdf_bake_document(fz_context *ctx, pdf_document *doc, int bake_annots, int bake_widgets);
+
+#endif