// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/native_file_system/file_system_chooser.h"

#include "base/bind.h"
#include "base/files/file_path.h"
#include "base/files/file_util.h"
#include "base/metrics/histogram_functions.h"
#include "base/strings/utf_string_conversions.h"
#include "base/task/post_task.h"
#include "build/build_config.h"
#include "content/browser/native_file_system/native_file_system_error.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/child_process_security_policy.h"
#include "content/public/browser/content_browser_client.h"
#include "content/public/browser/web_contents.h"
#include "content/public/common/content_client.h"
#include "storage/browser/fileapi/isolated_context.h"
#include "ui/shell_dialogs/select_file_policy.h"

namespace content {

namespace {

std::string TypeToString(blink::mojom::ChooseFileSystemEntryType type) {
  switch (type) {
    case blink::mojom::ChooseFileSystemEntryType::kOpenFile:
      return "OpenFile";
    case blink::mojom::ChooseFileSystemEntryType::kOpenMultipleFiles:
      return "OpenMultipleFiles";
    case blink::mojom::ChooseFileSystemEntryType::kSaveFile:
      return "SaveFile";
    case blink::mojom::ChooseFileSystemEntryType::kOpenDirectory:
      return "OpenDirectory";
  }
  NOTREACHED();
  return nullptr;
}

void RecordFileSelectionResult(blink::mojom::ChooseFileSystemEntryType type,
                               int count) {
  base::UmaHistogramCounts1000("NativeFileSystemAPI.FileChooserResult", count);
  base::UmaHistogramCounts1000(
      "NativeFileSystemAPI.FileChooserResult." + TypeToString(type), count);
}

bool GetFileTypesFromAcceptsOption(
    const blink::mojom::ChooseFileSystemEntryAcceptsOption& option,
    std::vector<base::FilePath::StringType>* extensions,
    base::string16* description) {
  std::set<base::FilePath::StringType> extension_set;

  for (const std::string& extension : option.extensions) {
#if defined(OS_WIN)
    extension_set.insert(base::UTF8ToWide(extension));
#else
    extension_set.insert(extension);
#endif
  }

  for (const std::string& mime_type : option.mime_types) {
    std::vector<base::FilePath::StringType> inner;
    net::GetExtensionsForMimeType(mime_type, &inner);
    if (inner.empty())
      continue;
    extension_set.insert(inner.begin(), inner.end());
  }

  extensions->assign(extension_set.begin(), extension_set.end());

  if (extensions->empty())
    return false;

  *description = option.description;
  return true;
}

ui::SelectFileDialog::FileTypeInfo ConvertAcceptsToFileTypeInfo(
    const std::vector<blink::mojom::ChooseFileSystemEntryAcceptsOptionPtr>&
        accepts,
    bool include_accepts_all) {
  ui::SelectFileDialog::FileTypeInfo file_types;
  file_types.include_all_files = include_accepts_all;

  for (const auto& option : accepts) {
    std::vector<base::FilePath::StringType> extensions;
    base::string16 description;

    if (!GetFileTypesFromAcceptsOption(*option, &extensions, &description))
      continue;  // No extensions were found for this option, skip it.

    file_types.extensions.push_back(extensions);
    // FileTypeInfo expects each set of extension to have a corresponding
    // description. A blank description will result in a system generated
    // description to be used.
    file_types.extension_description_overrides.push_back(description);
  }

  if (file_types.extensions.empty())
    file_types.include_all_files = true;

  return file_types;
}

}  // namespace

FileSystemChooser::Options::Options(
    blink::mojom::ChooseFileSystemEntryType type,
    std::vector<blink::mojom::ChooseFileSystemEntryAcceptsOptionPtr> accepts,
    bool include_accepts_all)
    : type_(type),
      file_types_(ConvertAcceptsToFileTypeInfo(accepts, include_accepts_all)) {}

// static
void FileSystemChooser::CreateAndShow(
    WebContents* web_contents,
    const Options& options,
    ResultCallback callback,
    scoped_refptr<base::TaskRunner> callback_runner) {
  DCHECK_CURRENTLY_ON(BrowserThread::UI);
  auto* listener = new FileSystemChooser(options.type(), std::move(callback),
                                         std::move(callback_runner));
  listener->dialog_ = ui::SelectFileDialog::Create(
      listener,
      GetContentClient()->browser()->CreateSelectFilePolicy(web_contents));
  // TODO(https://crbug.com/878581): Better/more specific options to pass to
  //     SelectFile.

  ui::SelectFileDialog::Type dialog_type = ui::SelectFileDialog::SELECT_NONE;
  switch (options.type()) {
    case blink::mojom::ChooseFileSystemEntryType::kOpenFile:
      dialog_type = ui::SelectFileDialog::SELECT_OPEN_FILE;
      break;
    case blink::mojom::ChooseFileSystemEntryType::kOpenMultipleFiles:
      dialog_type = ui::SelectFileDialog::SELECT_OPEN_MULTI_FILE;
      break;
    case blink::mojom::ChooseFileSystemEntryType::kSaveFile:
      dialog_type = ui::SelectFileDialog::SELECT_SAVEAS_FILE;
      break;
    case blink::mojom::ChooseFileSystemEntryType::kOpenDirectory:
      dialog_type = ui::SelectFileDialog::SELECT_FOLDER;
      break;
  }
  DCHECK_NE(dialog_type, ui::SelectFileDialog::SELECT_NONE);

  listener->dialog_->SelectFile(
      dialog_type, /*title=*/base::string16(),
      /*default_path=*/base::FilePath(), &options.file_type_info(),
      /*file_type_index=*/0,
      /*default_extension=*/base::FilePath::StringType(),
      web_contents ? web_contents->GetTopLevelNativeWindow() : nullptr,
      /*params=*/nullptr);
}

FileSystemChooser::FileSystemChooser(
    blink::mojom::ChooseFileSystemEntryType type,
    ResultCallback callback,
    scoped_refptr<base::TaskRunner> callback_runner)
    : callback_(std::move(callback)),
      callback_runner_(std::move(callback_runner)),
      type_(type) {}

FileSystemChooser::~FileSystemChooser() {
  if (dialog_)
    dialog_->ListenerDestroyed();
}

void FileSystemChooser::FileSelected(const base::FilePath& path,
                                     int index,
                                     void* params) {
  MultiFilesSelected({path}, params);
}

void FileSystemChooser::MultiFilesSelected(
    const std::vector<base::FilePath>& files,
    void* params) {
  auto* isolated_context = storage::IsolatedContext::GetInstance();
  DCHECK(isolated_context);

  RecordFileSelectionResult(type_, files.size());
  callback_runner_->PostTask(
      FROM_HERE,
      base::BindOnce(std::move(callback_), native_file_system_error::Ok(),
                     std::move(files)));
  delete this;
}

void FileSystemChooser::FileSelectionCanceled(void* params) {
  RecordFileSelectionResult(type_, 0);
  callback_runner_->PostTask(
      FROM_HERE,
      base::BindOnce(
          std::move(callback_),
          native_file_system_error::FromStatus(
              blink::mojom::NativeFileSystemStatus::kOperationAborted),
          std::vector<base::FilePath>()));
  delete this;
}

}  // namespace content