// Copyright 2024 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef PDF_PDFIUM_PDFIUM_INK_READER_H_
#define PDF_PDFIUM_PDFIUM_INK_READER_H_

#include <optional>
#include <vector>

#include "base/containers/span.h"
#include "base/memory/raw_ptr.h"
#include "pdf/buildflags.h"
#include "pdf/pdf_ink_text.h"
#include "third_party/ink/src/ink/geometry/mesh.h"
#include "third_party/ink/src/ink/geometry/partitioned_mesh.h"
#include "third_party/ink/src/ink/geometry/point.h"
#include "third_party/pdfium/public/fpdfview.h"

static_assert(BUILDFLAG(ENABLE_PDF_INK2), "ENABLE_PDF_INK2 not set to true");

namespace chrome_pdf {

struct ReadV2InkPathResult {
  FPDF_PAGEOBJECT page_object;
  ink::PartitionedMesh shape;
};

// Returns whether the given `page` contains a "V2" path created by Ink.
// Returns false if `page` is null.
bool PageContainsV2InkPath(FPDF_PAGE page);

// For the given `page`, iterate through all page objects and import "V2" paths
// created by Ink as ink::PartitionedMeshs. For each shape, also return its
// associated page object. The shapes do not have outlines and are only suitable
// for use with ink::Intersects().
//
// If a path does not match the characteristics of a "V2" path, or if the path
// cannot be properly tessellated, then it is ignored.
//
// If `page` is null, then the return value is an empty vector.
std::vector<ReadV2InkPathResult> ReadV2InkPathsFromPageAsModeledShapes(
    FPDF_PAGE page);

// Exposes internal CreateInkMeshFromPolyline() for testing.
std::optional<ink::Mesh> CreateInkMeshFromPolylineForTesting(
    base::span<const ink::Point> polyline);

struct ReadInkTextResult {
  ReadInkTextResult(
      InkTextBox textbox,
      std::vector<base::RawPtrIfPtrT<FPDF_PAGEOBJECT, DanglingUntriaged>>
          text_objects);
  ReadInkTextResult(const ReadInkTextResult&) = delete;
  ReadInkTextResult& operator=(const ReadInkTextResult&) = delete;
  ReadInkTextResult(ReadInkTextResult&&) noexcept;
  ReadInkTextResult& operator=(ReadInkTextResult&&) noexcept;
  ~ReadInkTextResult();

  InkTextBox textbox;
  std::vector<base::RawPtrIfPtrT<FPDF_PAGEOBJECT, DanglingUntriaged>>
      text_objects;
};

// Returns whether the given `page` contains any text annotations.
// Returns false if `page` is null.
bool PageContainsInkTextAnnotation(FPDF_PAGE page);

// For the given `page`, iterates through all page objects and reconstructs
// text annotations. For each textbox, groups internal text objects and returns
// their associated metadata and string payload, along with the underlying
// PDFium page objects.
//
// If a text object does not match the characteristics of a text annotation,
// or if it holds corrupted parameters, it is ignored.
//
// If `page` is null, then the return value is an empty vector.
std::vector<ReadInkTextResult> ReadInkTextAnnotationsFromPage(FPDF_PAGE page);

}  // namespace chrome_pdf

#endif  // PDF_PDFIUM_PDFIUM_INK_READER_H_