// Copyright (c) 2014 GitHub, Inc. All rights reserved.
// Use of this source code is governed by the MIT license that can be
// found in the LICENSE file.

#include "atom/browser/web_dialog_helper.h"

#include <string>
#include <vector>

#include "atom/browser/atom_browser_context.h"
#include "atom/browser/native_window.h"
#include "atom/browser/ui/file_dialog.h"
#include "base/bind.h"
#include "base/files/file_enumerator.h"
#include "base/files/file_path.h"
#include "base/strings/utf_string_conversions.h"
#include "chrome/common/pref_names.h"
#include "components/prefs/pref_service.h"
#include "content/public/browser/render_frame_host.h"
#include "content/public/browser/render_process_host.h"
#include "content/public/browser/render_view_host.h"
#include "content/public/browser/web_contents.h"
#include "content/public/common/file_chooser_file_info.h"
#include "content/public/common/file_chooser_params.h"
#include "net/base/mime_util.h"
#include "ui/shell_dialogs/selected_file_info.h"

namespace {

class FileSelectHelper : public base::RefCounted<FileSelectHelper>,
                         public content::WebContentsObserver {
 public:
  FileSelectHelper(content::RenderFrameHost* render_frame_host,
                   const content::FileChooserParams::Mode& mode)
      : render_frame_host_(render_frame_host), mode_(mode) {
    auto web_contents = content::WebContents::FromRenderFrameHost(
        render_frame_host);
    content::WebContentsObserver::Observe(web_contents);
  }

  void ShowOpenDialog(const file_dialog::DialogSettings& settings) {
    auto callback = base::Bind(&FileSelectHelper::OnOpenDialogDone, this);
    file_dialog::ShowOpenDialog(settings, callback);
  }

  void ShowSaveDialog(const file_dialog::DialogSettings& settings) {
    auto callback = base::Bind(&FileSelectHelper::OnSaveDialogDone, this);
    file_dialog::ShowSaveDialog(settings, callback);
  }

 private:
  friend class base::RefCounted<FileSelectHelper>;

  ~FileSelectHelper() override {}

  void OnOpenDialogDone(bool result, const std::vector<base::FilePath>& paths) {
    std::vector<content::FileChooserFileInfo> file_info;
    if (result) {
      for (auto& path : paths) {
        content::FileChooserFileInfo info;
        info.file_path = path;
        info.display_name = path.BaseName().value();
        file_info.push_back(info);
      }

      if (render_frame_host_ && !paths.empty()) {
        auto browser_context = static_cast<atom::AtomBrowserContext*>(
            render_frame_host_->GetProcess()->GetBrowserContext());
        browser_context->prefs()->SetFilePath(prefs::kSelectFileLastDirectory,
                                              paths[0].DirName());
      }
    }
    OnFilesSelected(file_info);
  }

  void OnSaveDialogDone(bool result, const base::FilePath& path) {
    std::vector<content::FileChooserFileInfo> file_info;
    if (result) {
      content::FileChooserFileInfo info;
      info.file_path = path;
      info.display_name = path.BaseName().value();
      file_info.push_back(info);
    }
    OnFilesSelected(file_info);
  }

  void OnFilesSelected(
      const std::vector<content::FileChooserFileInfo>& file_info) {
    if (render_frame_host_)
      render_frame_host_->FilesSelectedInChooser(file_info, mode_);
  }

  // content::WebContentsObserver:
  void RenderFrameHostChanged(content::RenderFrameHost* old_host,
                              content::RenderFrameHost* new_host) override {
    if (old_host == render_frame_host_)
      render_frame_host_ = nullptr;
  }

  // content::WebContentsObserver:
  void RenderFrameDeleted(content::RenderFrameHost* deleted_host) override {
    if (deleted_host == render_frame_host_)
      render_frame_host_ = nullptr;
  }

  // content::WebContentsObserver:
  void WebContentsDestroyed() override {
    render_frame_host_ = nullptr;
  }

  content::RenderFrameHost* render_frame_host_;
  content::FileChooserParams::Mode mode_;
};

file_dialog::Filters GetFileTypesFromAcceptType(
    const std::vector<base::string16>& accept_types) {
  file_dialog::Filters filters;
  if (accept_types.empty())
    return filters;

  std::vector<base::FilePath::StringType> extensions;

  int valid_type_count = 0;
  std::string description;

  for (const auto& accept_type : accept_types) {
    std::string ascii_type = base::UTF16ToASCII(accept_type);
    auto old_extension_size = extensions.size();

    if (ascii_type[0] == '.') {
      // If the type starts with a period it is assumed to be a file extension,
      // like `.txt`, // so we just have to add it to the list.
      base::FilePath::StringType extension(
          ascii_type.begin(), ascii_type.end());
      // Skip the first character.
      extensions.push_back(extension.substr(1));
    } else {
      if (ascii_type == "image/*")
        description = "Image Files";
      else if (ascii_type == "audio/*")
        description = "Audio Files";
      else if (ascii_type == "video/*")
        description = "Video Files";

      // For MIME Type, `audio/*, video/*, image/*
      net::GetExtensionsForMimeType(ascii_type, &extensions);
    }

    if (extensions.size() > old_extension_size)
      valid_type_count++;
  }

  // If no valid exntesion is added, return empty filters.
  if (extensions.empty())
    return filters;

  filters.push_back(file_dialog::Filter());

  if (valid_type_count > 1 ||
      (valid_type_count == 1 && description.empty() && extensions.size() > 1))
    description = "Custom Files";

  filters[0].first = description;

  for (const auto& extension : extensions) {
#if defined(OS_WIN)
    filters[0].second.push_back(base::UTF16ToASCII(extension));
#else
    filters[0].second.push_back(extension);
#endif
  }

  // Allow all files when extension is specified.
  filters.push_back(file_dialog::Filter());
  filters.back().first = "All Files";
  filters.back().second.push_back("*");

  return filters;
}

}  // namespace

namespace atom {

WebDialogHelper::WebDialogHelper(NativeWindow* window)
    : window_(window),
      weak_factory_(this) {
}

WebDialogHelper::~WebDialogHelper() {
}


void WebDialogHelper::RunFileChooser(
    content::RenderFrameHost* render_frame_host,
    const content::FileChooserParams& params) {
  std::vector<content::FileChooserFileInfo> result;

  file_dialog::DialogSettings settings;
  settings.filters = GetFileTypesFromAcceptType(params.accept_types);
  settings.parent_window = window_;
  settings.title = base::UTF16ToUTF8(params.title);

  scoped_refptr<FileSelectHelper> file_select_helper(
      new FileSelectHelper(render_frame_host, params.mode));
  if (params.mode == content::FileChooserParams::Save) {
    settings.default_path = params.default_file_name;
    file_select_helper->ShowSaveDialog(settings);
  } else {
    int flags = file_dialog::FILE_DIALOG_CREATE_DIRECTORY;
    switch (params.mode) {
      case content::FileChooserParams::OpenMultiple:
        flags |= file_dialog::FILE_DIALOG_MULTI_SELECTIONS;
      case content::FileChooserParams::Open:
        flags |= file_dialog::FILE_DIALOG_OPEN_FILE;
        break;
      case content::FileChooserParams::UploadFolder:
        flags |= file_dialog::FILE_DIALOG_OPEN_DIRECTORY;
        break;
      default:
        NOTREACHED();
    }

    AtomBrowserContext* browser_context = static_cast<AtomBrowserContext*>(
        window_->web_contents()->GetBrowserContext());
    if (!browser_context) {
      browser_context = static_cast<atom::AtomBrowserContext*>(
          render_frame_host->GetProcess()->GetBrowserContext());
    }
    settings.default_path = browser_context->prefs()->GetFilePath(
        prefs::kSelectFileLastDirectory).Append(params.default_file_name);
    settings.properties = flags;
    file_select_helper->ShowOpenDialog(settings);
  }
}

void WebDialogHelper::EnumerateDirectory(content::WebContents* web_contents,
                                         int request_id,
                                         const base::FilePath& dir) {
  int types = base::FileEnumerator::FILES |
              base::FileEnumerator::DIRECTORIES |
              base::FileEnumerator::INCLUDE_DOT_DOT;
  base::FileEnumerator file_enum(dir, false, types);

  base::FilePath path;
  std::vector<base::FilePath> paths;
  while (!(path = file_enum.Next()).empty())
    paths.push_back(path);

  web_contents->GetRenderViewHost()->DirectoryEnumerationFinished(
      request_id, paths);
}

}  // namespace atom
