// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40285824): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif

#include "ui/base/clipboard/clipboard_mac.h"

#import <Cocoa/Cocoa.h>
#include <stdint.h>

#include <algorithm>
#include <limits>
#include <string_view>

#include "base/apple/foundation_util.h"
#include "base/apple/scoped_cftyperef.h"
#include "base/containers/span.h"
#include "base/files/file_path.h"
#include "base/logging.h"
#include "base/mac/mac_util.h"
#include "base/memory/ref_counted_memory.h"
#include "base/notreached.h"
#include "base/strings/string_split.h"
#include "base/strings/string_util.h"
#include "base/strings/sys_string_conversions.h"
#include "base/strings/utf_string_conversions.h"
#include "base/task/task_traits.h"
#include "base/task/thread_pool.h"
#include "base/threading/thread_restrictions.h"
#include "net/base/filename_util.h"
#include "skia/ext/skia_utils_base.h"
#include "skia/ext/skia_utils_mac.h"
#include "third_party/skia/include/core/SkBitmap.h"
#include "ui/base/clipboard/clipboard_constants.h"
#include "ui/base/clipboard/clipboard_format_type.h"
#include "ui/base/clipboard/clipboard_metrics.h"
#include "ui/base/clipboard/clipboard_monitor.h"
#include "ui/base/clipboard/clipboard_util_mac.h"
#include "ui/base/clipboard/custom_data_helper.h"
#include "ui/base/data_transfer_policy/data_transfer_endpoint.h"
#include "ui/gfx/canvas.h"
#include "ui/gfx/codec/png_codec.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gfx/image/image.h"
#include "ui/gfx/scoped_ns_graphics_context_save_gstate_mac.h"
#include "url/gurl.h"

namespace ui {

namespace {

NSPasteboard* GetPasteboard() {
  // The pasteboard can always be nil, since there is a finite amount of storage
  // that must be shared between all pasteboards.
  NSPasteboard* pasteboard = NSPasteboard.generalPasteboard;
  return pasteboard;
}

NSImage* GetNSImage(NSPasteboard* pasteboard) {
  // If the pasteboard's image data is not to its liking, the guts of NSImage
  // may throw, and that exception will leak. Prevent a crash in that case;
  // a blank image is better.
  NSImage* image;
  @try {
    if (pasteboard) {
      image = [[NSImage alloc] initWithPasteboard:pasteboard];
    }
  } @catch (id exception) {
  }
  if (!image) {
    return nil;
  }
  if (image.representations.count == 0u) {
    return nil;
  }
  return image;
}

// Read raw PNG bytes from the clipboard.
std::vector<uint8_t> GetPngFromPasteboard(NSPasteboard* pasteboard) {
  if (!pasteboard) {
    return {};
  }

  NSData* data = [pasteboard dataForType:NSPasteboardTypePNG];
  auto span = base::apple::NSDataToSpan(data);
  return {span.begin(), span.end()};
}

std::vector<uint8_t> EncodeGfxImageToPng(gfx::Image image) {
  base::AssertLongCPUWorkAllowed();

  if (image.IsEmpty()) {
    return {};
  }

  scoped_refptr<base::RefCountedMemory> mem = image.As1xPNGBytes();
  std::vector<uint8_t> image_data(mem->data(), mem->data() + mem->size());
  return image_data;
}

}  // namespace

// Clipboard factory method.
// static
Clipboard* Clipboard::Create() {
  return new ClipboardMac;
}

// ClipboardMac implementation.
ClipboardMac::ClipboardMac() {
  DCHECK(CalledOnValidThread());
}

ClipboardMac::~ClipboardMac() {
  DCHECK(CalledOnValidThread());
}

void ClipboardMac::OnPreShutdown() {}

std::optional<DataTransferEndpoint> ClipboardMac::GetSource(
    ClipboardBuffer buffer) const {
  return GetSourceInternal(buffer, GetPasteboard());
}

std::optional<DataTransferEndpoint> ClipboardMac::GetSourceInternal(
    ClipboardBuffer buffer,
    NSPasteboard* pasteboard) const {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);

  NSString* source_url = [pasteboard stringForType:kUTTypeChromiumSourceUrl];

  if (!source_url) {
    return std::nullopt;
  }

  GURL gurl(base::SysNSStringToUTF8(source_url));
  if (!gurl.is_valid()) {
    return std::nullopt;
  }

  return DataTransferEndpoint(std::move(gurl));
}

const ClipboardSequenceNumberToken& ClipboardMac::GetSequenceNumber(
    ClipboardBuffer buffer) const {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);

  NSInteger sequence_number = [GetPasteboard() changeCount];
  if (sequence_number != clipboard_sequence_.sequence_number) {
    // Generate a unique token associated with the current sequence number.
    clipboard_sequence_ = {sequence_number, ClipboardSequenceNumberToken()};
  }
  return clipboard_sequence_.token;
}

// |data_dst| is not used. It's only passed to be consistent with other
// platforms.
bool ClipboardMac::IsFormatAvailable(
    const ClipboardFormatType& format,
    ClipboardBuffer buffer,
    const DataTransferEndpoint* data_dst) const {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);

  // https://crbug.com/1016740#c21: The pasteboard types array may end up going
  // away; make a copy.
  NSArray* types = [GetPasteboard().types copy];

  // Safari only places RTF on the pasteboard, never HTML. We can convert RTF
  // to HTML, so the presence of either indicates success when looking for HTML.
  if (format == ClipboardFormatType::HtmlType()) {
    return [types containsObject:NSPasteboardTypeHTML] ||
           [types containsObject:NSPasteboardTypeRTF];
  }
  // Chrome can retrieve an image from the clipboard as either a bitmap or PNG.
  if (format == ClipboardFormatType::PngType() ||
      format == ClipboardFormatType::BitmapType()) {
    return [types containsObject:NSPasteboardTypePNG] ||
           [types containsObject:NSPasteboardTypeTIFF];
  }
  return [types containsObject:format.ToNSString()];
}

bool ClipboardMac::IsMarkedByOriginatorAsConfidential() const {
  DCHECK(CalledOnValidThread());

  NSPasteboardType type =
      [GetPasteboard() availableTypeFromArray:@[ kUTTypeConfidentialData ]];

  if (type)
    return true;

  return false;
}

void ClipboardMac::Clear(ClipboardBuffer buffer) {
  ClearInternal(buffer, GetPasteboard());
}

void ClipboardMac::ClearInternal(ClipboardBuffer buffer,
                                 NSPasteboard* pasteboard) {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);

  [pasteboard clearContents];
}

std::vector<std::u16string> ClipboardMac::GetStandardFormats(
    ClipboardBuffer buffer,
    const DataTransferEndpoint* data_dst) const {
  std::vector<std::u16string> types;
  NSPasteboard* pb = GetPasteboard();
  if (IsFormatAvailable(ClipboardFormatType::PlainTextType(), buffer,
                        data_dst)) {
    types.push_back(kMimeTypePlainText16);
  }
  if (IsFormatAvailable(ClipboardFormatType::HtmlType(), buffer, data_dst)) {
    types.push_back(kMimeTypeHtml16);
  }
  if (IsFormatAvailable(ClipboardFormatType::SvgType(), buffer, data_dst)) {
    types.push_back(kMimeTypeSvg16);
  }
  if (IsFormatAvailable(ClipboardFormatType::RtfType(), buffer, data_dst)) {
    types.push_back(kMimeTypeRtf16);
  }
  if (IsFormatAvailable(ClipboardFormatType::FilenamesType(), buffer,
                        data_dst)) {
    types.push_back(kMimeTypeUriList16);
  } else if (pb && [NSImage canInitWithPasteboard:pb]) {
    // Finder Cmd+C places both file and icon onto the clipboard
    // (http://crbug.com/553686), so ignore images if we have detected files.
    // This means that if an image is present with file content, we will always
    // ignore the image, but this matches observable Safari behavior.
    types.push_back(kMimeTypePng16);
  }
  return types;
}

// |data_dst| is not used. It's only passed to be consistent with other
// platforms.
void ClipboardMac::ReadAvailableTypes(
    ClipboardBuffer buffer,
    const DataTransferEndpoint* data_dst,
    std::vector<std::u16string>* types) const {
  DCHECK(CalledOnValidThread());
  DCHECK(types);

  NSPasteboard* pb = GetPasteboard();
  types->clear();
  *types = GetStandardFormats(buffer, data_dst);

  if ([pb.types containsObject:kUTTypeChromiumDataTransferCustomData]) {
    NSData* data = [pb dataForType:kUTTypeChromiumDataTransferCustomData];
    if ([data length]) {
      ReadCustomDataTypes(base::apple::NSDataToSpan(data), types);
    }
  }
}

// |data_dst| is not used. It's only passed to be consistent with other
// platforms.
void ClipboardMac::ReadText(ClipboardBuffer buffer,
                            const DataTransferEndpoint* data_dst,
                            std::u16string* result) const {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);
  RecordRead(ClipboardFormatMetric::kText);
  NSString* contents = [GetPasteboard() stringForType:NSPasteboardTypeString];

  *result = base::SysNSStringToUTF16(contents);
}

// |data_dst| is not used. It's only passed to be consistent with other
// platforms.
void ClipboardMac::ReadAsciiText(ClipboardBuffer buffer,
                                 const DataTransferEndpoint* data_dst,
                                 std::string* result) const {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);
  RecordRead(ClipboardFormatMetric::kText);
  NSString* contents = [GetPasteboard() stringForType:NSPasteboardTypeString];

  if (!contents)
    result->clear();
  else
    result->assign(base::SysNSStringToUTF8(contents));
}

// |data_dst| is not used. It's only passed to be consistent with other
// platforms.
void ClipboardMac::ReadHTML(ClipboardBuffer buffer,
                            const DataTransferEndpoint* data_dst,
                            std::u16string* markup,
                            std::string* src_url,
                            uint32_t* fragment_start,
                            uint32_t* fragment_end) const {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);
  RecordRead(ClipboardFormatMetric::kHtml);

  // TODO(avi): src_url?
  markup->clear();
  if (src_url)
    src_url->clear();

  NSPasteboard* pb = GetPasteboard();
  NSArray* supportedTypes =
      @[ NSPasteboardTypeHTML, NSPasteboardTypeRTF, NSPasteboardTypeString ];
  NSString* bestType = [pb availableTypeFromArray:supportedTypes];
  if (bestType) {
    NSString* contents;
    if ([bestType isEqualToString:NSPasteboardTypeRTF]) {
      contents = clipboard_util::GetHTMLFromRTFOnPasteboard(pb);
    } else {
      contents = [pb stringForType:bestType];
    }
    *markup = base::SysNSStringToUTF16(contents);
  }

  *fragment_start = 0;
  DCHECK_LE(markup->length(), std::numeric_limits<uint32_t>::max());
  *fragment_end = static_cast<uint32_t>(markup->length());
}

void ClipboardMac::ReadSvg(ClipboardBuffer buffer,
                           const DataTransferEndpoint* data_dst,
                           std::u16string* result) const {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);
  RecordRead(ClipboardFormatMetric::kSvg);
  NSString* contents = [GetPasteboard()
      stringForType:ClipboardFormatType::SvgType().ToNSString()];

  *result = base::SysNSStringToUTF16(contents);
}

// |data_dst| is not used. It's only passed to be consistent with other
// platforms.
void ClipboardMac::ReadRTF(ClipboardBuffer buffer,
                           const DataTransferEndpoint* data_dst,
                           std::string* result) const {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);
  RecordRead(ClipboardFormatMetric::kRtf);

  return ReadData(ClipboardFormatType::RtfType(), data_dst, result);
}

// |data_dst| is not used. It's only passed to be consistent with other
// platforms.
void ClipboardMac::ReadPng(ClipboardBuffer buffer,
                           const DataTransferEndpoint* data_dst,
                           ReadPngCallback callback) const {
  RecordRead(ClipboardFormatMetric::kPng);
  ReadPngInternal(buffer, GetPasteboard(), std::move(callback));
}

// |data_dst| is not used. It's only passed to be consistent with other
// platforms.
void ClipboardMac::ReadDataTransferCustomData(
    ClipboardBuffer buffer,
    const std::u16string& type,
    const DataTransferEndpoint* data_dst,
    std::u16string* result) const {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);
  RecordRead(ClipboardFormatMetric::kCustomData);

  NSPasteboard* pb = GetPasteboard();
  if ([[pb types] containsObject:kUTTypeChromiumDataTransferCustomData]) {
    NSData* data = [pb dataForType:kUTTypeChromiumDataTransferCustomData];
    if ([data length]) {
      if (std::optional<std::u16string> maybe_result =
              ReadCustomDataForType(base::apple::NSDataToSpan(data), type);
          maybe_result) {
        *result = std::move(*maybe_result);
      }
    }
  }
}

// |data_dst| is not used. It's only passed to be consistent with other
// platforms.
void ClipboardMac::ReadFilenames(ClipboardBuffer buffer,
                                 const DataTransferEndpoint* data_dst,
                                 std::vector<ui::FileInfo>* result) const {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);
  RecordRead(ClipboardFormatMetric::kFilenames);

  std::vector<ui::FileInfo> files =
      clipboard_util::FilesFromPasteboard(GetPasteboard());
  std::ranges::move(files, std::back_inserter(*result));
}

// |data_dst| is not used. It's only passed to be consistent with other
// platforms.
void ClipboardMac::ReadBookmark(const DataTransferEndpoint* data_dst,
                                std::u16string* title,
                                std::string* url) const {
  DCHECK(CalledOnValidThread());
  RecordRead(ClipboardFormatMetric::kBookmark);
  NSPasteboard* pb = GetPasteboard();

  if (title) {
    NSString* contents = [pb stringForType:kUTTypeUrlName];
    *title = base::SysNSStringToUTF16(contents);
  }

  if (url) {
    NSString* url_string = [pb stringForType:NSPasteboardTypeURL];
    if (!url_string)
      url->clear();
    else
      url->assign(base::SysNSStringToUTF8(url_string));
  }
}

// |data_dst| is not used. It's only passed to be consistent with other
// platforms.
void ClipboardMac::ReadData(const ClipboardFormatType& format,
                            const DataTransferEndpoint* data_dst,
                            std::string* result) const {
  DCHECK(CalledOnValidThread());
  RecordRead(ClipboardFormatMetric::kData);
  NSData* data = [GetPasteboard() dataForType:format.ToNSString()];
  if ([data length])
    *result = as_string_view(base::apple::NSDataToSpan(data));
}

void ClipboardMac::WritePortableAndPlatformRepresentations(
    ClipboardBuffer buffer,
    const ObjectMap& objects,
    const std::vector<RawData>& raw_objects,
    std::vector<Clipboard::PlatformRepresentation> platform_representations,
    std::unique_ptr<DataTransferEndpoint> data_src,
    uint32_t privacy_types) {
  WritePortableAndPlatformRepresentationsInternal(
      buffer, objects, std::move(raw_objects),
      std::move(platform_representations), std::move(data_src), GetPasteboard(),
      privacy_types);
}

void ClipboardMac::WritePortableAndPlatformRepresentationsInternal(
    ClipboardBuffer buffer,
    const ObjectMap& objects,
    const std::vector<RawData>& raw_objects,
    std::vector<Clipboard::PlatformRepresentation> platform_representations,
    std::unique_ptr<DataTransferEndpoint> data_src,
    NSPasteboard* pasteboard,
    uint32_t privacy_types) {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);

  if (privacy_types & Clipboard::PrivacyTypes::kNoCloudClipboard) {
    WriteUploadCloudClipboard();
  }

  [pasteboard declareTypes:@[] owner:nil];

  DispatchPlatformRepresentations(std::move(platform_representations));
  for (const auto& object : objects) {
    DispatchPortableRepresentation(object.second);
  }
  for (const auto& raw_object : raw_objects) {
    DispatchPortableRepresentation(raw_object);
  }

  if (data_src && data_src->IsUrlType()) {
    [pasteboard setString:base::SysUTF8ToNSString(data_src->GetURL()->spec())
                  forType:kUTTypeChromiumSourceUrl];
  }
  if (privacy_types & Clipboard::PrivacyTypes::kNoDisplay) {
    WriteConfidentialDataForPassword();
  }
  ClipboardMonitor::GetInstance()->NotifyClipboardDataChanged();
}

void ClipboardMac::WriteText(std::string_view text) {
  [GetPasteboard() setString:base::SysUTF8ToNSString(text)
                     forType:NSPasteboardTypeString];
}

void ClipboardMac::WriteHTML(std::string_view markup,
                             std::optional<std::string_view> /* source_url */) {
  // We need to mark it as utf-8. (see crbug.com/40759159)
  std::string html_fragment_str("<meta charset='utf-8'>");
  html_fragment_str.append(markup);
  NSString* html_fragment = base::SysUTF8ToNSString(html_fragment_str);

  [GetPasteboard() setString:html_fragment forType:NSPasteboardTypeHTML];
}

void ClipboardMac::WriteSvg(std::string_view markup) {
  [GetPasteboard() setString:base::SysUTF8ToNSString(markup)
                     forType:ClipboardFormatType::SvgType().ToNSString()];
}

void ClipboardMac::WriteRTF(std::string_view rtf) {
  WriteData(ClipboardFormatType::RtfType(), base::as_byte_span(rtf));
}

void ClipboardMac::WriteFilenames(std::vector<ui::FileInfo> filenames) {
  clipboard_util::WriteFilesToPasteboard(GetPasteboard(), filenames);
}

void ClipboardMac::WriteBookmark(std::string_view title, std::string_view url) {
  NSArray<NSPasteboardItem*>* items = clipboard_util::PasteboardItemsFromUrls(
      @[ base::SysUTF8ToNSString(url) ], @[ base::SysUTF8ToNSString(title) ]);
  clipboard_util::AddDataToPasteboard(GetPasteboard(), items.firstObject);
}

void ClipboardMac::WriteBitmap(const SkBitmap& bitmap) {
  // The bitmap type is sanitized to be N32 before we get here. The conversion
  // to an NSImage would not explode if we got this wrong, so this is not a
  // security CHECK.
  DCHECK_EQ(bitmap.colorType(), kN32_SkColorType);

  WriteBitmapInternal(bitmap, GetPasteboard());
}

void ClipboardMac::WriteData(const ClipboardFormatType& format,
                             base::span<const uint8_t> data) {
  [GetPasteboard() setData:[NSData dataWithBytes:data.data() length:data.size()]
                   forType:format.ToNSString()];
}

void ClipboardMac::WriteClipboardHistory() {
  // TODO(crbug.com/40945200): Add support for this.
}

void ClipboardMac::WriteUploadCloudClipboard() {
  // Make the pasteboard content current host only.
  [GetPasteboard()
      prepareForNewContentsWithOptions:NSPasteboardContentsCurrentHostOnly];
}

void ClipboardMac::WriteConfidentialDataForPassword() {
  DCHECK(CalledOnValidThread());

  [GetPasteboard() setData:nil forType:kUTTypeConfidentialData];
}

// Write an extra flavor that signifies WebKit was the last to modify the
// pasteboard. This flavor has no data.
void ClipboardMac::WriteWebSmartPaste() {
  NSString* format = ClipboardFormatType::WebKitSmartPasteType().ToNSString();
  [GetPasteboard() setData:nil forType:format];
}

void ClipboardMac::ReadPngInternal(ClipboardBuffer buffer,
                                   NSPasteboard* pasteboard,
                                   ReadPngCallback callback) const {
  DCHECK(CalledOnValidThread());
  DCHECK_EQ(buffer, ClipboardBuffer::kCopyPaste);

  std::vector<uint8_t> png = GetPngFromPasteboard(pasteboard);
  if (!png.empty()) {
    std::move(callback).Run(std::move(png));
    return;
  }

  // If we can’t read a PNG, try reading for an NSImage, and if successful,
  // transcode it to PNG.
  NSImage* image = GetNSImage(pasteboard);
  if (!image) {
    std::move(callback).Run({});
    return;
  }

  auto gfx_image = gfx::Image(image);
  if (gfx_image.IsEmpty()) {
    std::move(callback).Run({});
    return;
  }

  base::ThreadPool::PostTaskAndReplyWithResult(
      FROM_HERE, {base::MayBlock(), base::TaskPriority::USER_BLOCKING},
      base::BindOnce(&EncodeGfxImageToPng, std::move(gfx_image)),
      std::move(callback));
}

void ClipboardMac::WriteBitmapInternal(const SkBitmap& bitmap,
                                       NSPasteboard* pasteboard) {
  // The bitmap type is sanitized to be N32 before we get here. The conversion
  // to an NSImage would not explode if we got this wrong, so this is not a
  // security CHECK.
  DCHECK_EQ(bitmap.colorType(), kN32_SkColorType);

  NSBitmapImageRep* image_rep = skia::SkBitmapToNSBitmapImageRep(bitmap);
  CHECK(image_rep) << "SkBitmapToNSBitmapImageRep failed";
  // Attempt to format the image representation as a PNG, and write it directly
  // to the clipboard if this succeeds. This will write both a PNG and a TIFF.
  NSData* data = [image_rep representationUsingType:NSBitmapImageFileTypePNG
                                         properties:@{}];
  if (data) {
    NSPasteboardItem* pasteboard_item = [[NSPasteboardItem alloc] init];
    [pasteboard_item setData:data forType:NSPasteboardTypePNG];
    if ([pasteboard writeObjects:@[ pasteboard_item ]]) {
      return;
    }
  }

  // Otherwise, fall back to writing the NSImage directly to the clipboard,
  // which will write only a TIFF.
  NSImage* image = [[NSImage alloc] init];
  [image addRepresentation:image_rep];
  [image setSize:NSMakeSize(bitmap.width(), bitmap.height())];
  [pasteboard writeObjects:@[ image ]];
}

}  // namespace ui