// Copyright 2022 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CHROME_BROWSER_WEB_APPLICATIONS_OS_INTEGRATION_MAC_ICNS_ENCODER_H_
#define CHROME_BROWSER_WEB_APPLICATIONS_OS_INTEGRATION_MAC_ICNS_ENCODER_H_
#include <vector>
#include "base/containers/span.h"
namespace base {
class File;
class FilePath;
} // namespace base
namespace gfx {
class Image;
}
namespace web_app {
// This class can be used to construct an icon in .icns file format. Create
// an instance, repeatedly call `AddImage` to add various sizes of the icon, and
// finally call `WriteToFile` to write the .icns file to disk.
class IcnsEncoder {
public:
IcnsEncoder();
~IcnsEncoder();
// Adds another representation of the same icon to this encoder. Returns false
// if the image can not be added to a .icns file, for example because it has
// the wrong dimensions, the wrong color type, or because encoding failed.
bool AddImage(const gfx::Image& image);
// Writes all the images that were successfully added to this encoder to
// `path` in the .icns file format. Returns false if saving to disk failed for
// some reason.
bool WriteToFile(const base::FilePath& path) const;
// Appends a run-length-encoded copy of `data` to `rle_data`, using the
// encoding scheme used by the .icns file format. Public for testing.
static void AppendRLEImageData(base::span<const uint8_t> data,
std::vector<uint8_t>* rle_data);
private:
// The .icns file format is made up of blocks, consistent of a type and data.
// This struct represents such a block.
struct Block {
explicit Block(uint32_t type, std::vector<uint8_t> data = {});
~Block();
Block(Block&&);
Block& operator=(Block&&);
// Type of this block.
uint32_t type;
// Data contained in the block, not including the header.
std::vector<uint8_t> data;
};
// Number of bytes a single block header takes up.
static constexpr size_t kBlockHeaderSize = 8;
// Adds a block to the list of blocks making up this .icns file.
void AppendBlock(uint32_t type, std::vector<uint8_t> data);
// Writes `block` to `file`, including its header.
static bool WriteBlockToFile(base::File& file, const Block& block);
// The blocks making up this .icns file, not including the table of contents
// block that will also be written to a file.
std::vector<Block> blocks_;
// The total size of all the blocks in `blocks_`. This also includes the size
// of the headers for these blocks.
size_t total_block_size_ = 0;
};
} // namespace web_app
#endif // CHROME_BROWSER_WEB_APPLICATIONS_OS_INTEGRATION_MAC_ICNS_ENCODER_H_