// Copyright (c) 2011 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 "chrome/browser/printing/print_dialog_gtk.h"

#include <fcntl.h>
#include <gtk/gtkpagesetupunixdialog.h>
#include <gtk/gtkprintjob.h>
#include <sys/stat.h>
#include <sys/types.h>

#include <string>
#include <vector>

#include "base/file_util.h"
#include "base/file_util_proxy.h"
#include "base/logging.h"
#include "base/synchronization/waitable_event.h"
#include "base/utf_string_conversions.h"
#include "chrome/browser/ui/browser_list.h"
#include "chrome/browser/ui/browser_window.h"
#include "printing/metafile.h"
#include "printing/print_job_constants.h"
#include "printing/print_settings_initializer_gtk.h"

using printing::PageRanges;
using printing::PrintSettings;

namespace {

// Helper class to track GTK printers.
class GtkPrinterList {
 public:
  GtkPrinterList() : default_printer_(NULL) {
    gtk_enumerate_printers((GtkPrinterFunc)SetPrinter, this, NULL, TRUE);
  }

  ~GtkPrinterList() {
    for (std::vector<GtkPrinter*>::iterator it = printers_.begin();
         it < printers_.end(); ++it) {
      g_object_unref(*it);
    }
  }

  // Can return NULL if there's no default printer. E.g. Printer on a laptop
  // is "home_printer", but the laptop is at work.
  GtkPrinter* default_printer() {
    return default_printer_;
  }

  // Can return NULL if the printer cannot be found due to:
  // - Printer list out of sync with printer dialog UI.
  // - Querying for non-existant printers like 'Print to PDF'.
  GtkPrinter* GetPrinterWithName(const char* name) {
    if (!name || !*name)
      return NULL;

    for (std::vector<GtkPrinter*>::iterator it = printers_.begin();
         it < printers_.end(); ++it) {
      if (strcmp(name, gtk_printer_get_name(*it)) == 0) {
        return *it;
      }
    }

    return NULL;
  }

 private:
  // Callback function used by gtk_enumerate_printers() to get all printer.
  static bool SetPrinter(GtkPrinter* printer, GtkPrinterList* printer_list) {
    if (gtk_printer_is_default(printer))
      printer_list->default_printer_ = printer;

    g_object_ref(printer);
    printer_list->printers_.push_back(printer);

    return false;
  }

  std::vector<GtkPrinter*> printers_;
  GtkPrinter* default_printer_;
};

}  // namespace

// static
printing::PrintDialogGtkInterface* PrintDialogGtk::CreatePrintDialog(
    PrintingContextCairo* context) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  return new PrintDialogGtk(context);
}

PrintDialogGtk::PrintDialogGtk(PrintingContextCairo* context)
    : callback_(NULL),
      context_(context),
      dialog_(NULL),
      gtk_settings_(NULL),
      page_setup_(NULL),
      printer_(NULL) {
}

PrintDialogGtk::~PrintDialogGtk() {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));

  if (dialog_) {
    gtk_widget_destroy(dialog_);
    dialog_ = NULL;
  }
  if (gtk_settings_) {
    g_object_unref(gtk_settings_);
    gtk_settings_ = NULL;
  }
  if (page_setup_) {
    g_object_unref(page_setup_);
    page_setup_ = NULL;
  }
  if (printer_) {
    g_object_unref(printer_);
    printer_ = NULL;
  }
}

void PrintDialogGtk::UseDefaultSettings() {
  DCHECK(!save_document_event_.get());
  DCHECK(!page_setup_);

  // |gtk_settings_| is a new object.
  gtk_settings_ = gtk_print_settings_new();

  scoped_ptr<GtkPrinterList> printer_list(new GtkPrinterList);
  printer_ = printer_list->default_printer();
  if (printer_) {
    g_object_ref(printer_);
    gtk_print_settings_set_printer(gtk_settings_,
                                   gtk_printer_get_name(printer_));
#if GTK_CHECK_VERSION(2, 14, 0)
    page_setup_ = gtk_printer_get_default_page_size(printer_);
#endif
  }

  if (!page_setup_)
    page_setup_ = gtk_page_setup_new();

  // No page range to initialize for default settings.
  PageRanges ranges_vector;
  InitPrintSettings(ranges_vector);
}

bool PrintDialogGtk::UpdateSettings(const DictionaryValue& settings,
                                    const printing::PageRanges& ranges) {
  std::string printer_name;
  settings.GetString(printing::kSettingPrinterName, &printer_name);

  scoped_ptr<GtkPrinterList> printer_list(new GtkPrinterList);
  printer_ = printer_list->GetPrinterWithName(printer_name.c_str());
  if (printer_) {
    g_object_ref(printer_);
    gtk_print_settings_set_printer(gtk_settings_,
                                   gtk_printer_get_name(printer_));
  }

  bool landscape;
  if (!settings.GetBoolean(printing::kSettingLandscape, &landscape))
    return false;

  gtk_print_settings_set_orientation(
      gtk_settings_,
      landscape ? GTK_PAGE_ORIENTATION_LANDSCAPE :
                  GTK_PAGE_ORIENTATION_PORTRAIT);

  int copies;
  if (!settings.GetInteger(printing::kSettingCopies, &copies))
    return false;
  gtk_print_settings_set_n_copies(gtk_settings_, copies);

  bool collate;
  if (!settings.GetBoolean(printing::kSettingCollate, &collate))
    return false;
  gtk_print_settings_set_collate(gtk_settings_, collate);

  // TODO(thestig) Color: gtk_print_settings_set_color() does not work.
  // TODO(thestig) Duplex: gtk_print_settings_set_duplex() does not work.

  InitPrintSettings(ranges);
  return true;
}

void PrintDialogGtk::ShowDialog(
    PrintingContextCairo::PrintSettingsCallback* callback) {
  DCHECK(!save_document_event_.get());

  callback_ = callback;

  GtkWindow* parent = BrowserList::GetLastActive()->window()->GetNativeHandle();
  // TODO(estade): We need a window title here.
  dialog_ = gtk_print_unix_dialog_new(NULL, parent);

  // Set modal so user cannot focus the same tab and press print again.
  gtk_window_set_modal(GTK_WINDOW(dialog_), TRUE);

  // Since we only generate PDF, only show printers that support PDF.
  // TODO(thestig) Add more capabilities to support?
  GtkPrintCapabilities cap = static_cast<GtkPrintCapabilities>(
      GTK_PRINT_CAPABILITY_GENERATE_PDF |
      GTK_PRINT_CAPABILITY_PAGE_SET |
      GTK_PRINT_CAPABILITY_COPIES |
      GTK_PRINT_CAPABILITY_COLLATE |
      GTK_PRINT_CAPABILITY_REVERSE);
  gtk_print_unix_dialog_set_manual_capabilities(GTK_PRINT_UNIX_DIALOG(dialog_),
                                                cap);
#if GTK_CHECK_VERSION(2, 18, 0)
  gtk_print_unix_dialog_set_embed_page_setup(GTK_PRINT_UNIX_DIALOG(dialog_),
                                             TRUE);
#endif
  g_signal_connect(dialog_, "response", G_CALLBACK(OnResponseThunk), this);
  gtk_widget_show(dialog_);
}

void PrintDialogGtk::PrintDocument(const printing::Metafile* metafile,
                                   const string16& document_name) {
  // This runs on the print worker thread, does not block the UI thread.
  DCHECK(!BrowserThread::CurrentlyOn(BrowserThread::UI));

  // The document printing tasks can outlive the PrintingContext that created
  // this dialog.
  AddRef();
  DCHECK(!save_document_event_.get());
  save_document_event_.reset(new base::WaitableEvent(false, false));

  BrowserThread::PostTask(
      BrowserThread::FILE, FROM_HERE,
      NewRunnableMethod(this,
                        &PrintDialogGtk::SaveDocumentToDisk,
                        metafile,
                        document_name));
  // Wait for SaveDocumentToDisk() to finish.
  save_document_event_->Wait();
}

void PrintDialogGtk::AddRefToDialog() {
  AddRef();
}

void PrintDialogGtk::ReleaseDialog() {
  Release();
}

void PrintDialogGtk::OnResponse(GtkWidget* dialog, int response_id) {
  gtk_widget_hide(dialog_);

  switch (response_id) {
    case GTK_RESPONSE_OK: {
      if (gtk_settings_)
        g_object_unref(gtk_settings_);
      gtk_settings_ = gtk_print_unix_dialog_get_settings(
          GTK_PRINT_UNIX_DIALOG(dialog_));

      if (printer_)
        g_object_unref(printer_);
      printer_ = gtk_print_unix_dialog_get_selected_printer(
          GTK_PRINT_UNIX_DIALOG(dialog_));
      g_object_ref(printer_);

      if (page_setup_)
        g_object_unref(page_setup_);
      page_setup_ = gtk_print_unix_dialog_get_page_setup(
          GTK_PRINT_UNIX_DIALOG(dialog_));
      g_object_ref(page_setup_);

      // Handle page ranges.
      PageRanges ranges_vector;
      gint num_ranges;
      GtkPageRange* gtk_range =
          gtk_print_settings_get_page_ranges(gtk_settings_, &num_ranges);
      if (gtk_range) {
        for (int i = 0; i < num_ranges; ++i) {
          printing::PageRange range;
          range.from = gtk_range[i].start;
          range.to = gtk_range[i].end;
          ranges_vector.push_back(range);
        }
        g_free(gtk_range);
      }

      PrintSettings settings;
      printing::PrintSettingsInitializerGtk::InitPrintSettings(
          gtk_settings_, page_setup_, ranges_vector, false, &settings);
      context_->InitWithSettings(settings);
      callback_->Run(PrintingContextCairo::OK);
      callback_ = NULL;
      return;
    }
    case GTK_RESPONSE_DELETE_EVENT:  // Fall through.
    case GTK_RESPONSE_CANCEL: {
      callback_->Run(PrintingContextCairo::CANCEL);
      callback_ = NULL;
      return;
    }
    case GTK_RESPONSE_APPLY:
    default: {
      NOTREACHED();
    }
  }
}

void PrintDialogGtk::SaveDocumentToDisk(const printing::Metafile* metafile,
                                        const string16& document_name) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));

  bool error = false;
  if (!file_util::CreateTemporaryFile(&path_to_pdf_)) {
    LOG(ERROR) << "Creating temporary file failed";
    error = true;
  }

  if (!error && !metafile->SaveTo(path_to_pdf_)) {
    LOG(ERROR) << "Saving metafile failed";
    file_util::Delete(path_to_pdf_, false);
    error = true;
  }

  // Done saving, let PrintDialogGtk::PrintDocument() continue.
  save_document_event_->Signal();

  if (error) {
    // Matches AddRef() in PrintDocument();
    Release();
  } else {
    // No errors, continue printing.
    BrowserThread::PostTask(
        BrowserThread::UI, FROM_HERE,
        NewRunnableMethod(this,
                          &PrintDialogGtk::SendDocumentToPrinter,
                          document_name));
  }
}

void PrintDialogGtk::SendDocumentToPrinter(const string16& document_name) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));

  // If |printer_| is NULL then somehow the GTK printer list changed out under
  // us. In which case, just bail out.
  if (!printer_) {
    // Matches AddRef() in PrintDocument();
    Release();
    return;
  }

  GtkPrintJob* print_job = gtk_print_job_new(
      UTF16ToUTF8(document_name).c_str(),
      printer_,
      gtk_settings_,
      page_setup_);
  gtk_print_job_set_source_file(print_job, path_to_pdf_.value().c_str(), NULL);
  gtk_print_job_send(print_job, OnJobCompletedThunk, this, NULL);
}

// static
void PrintDialogGtk::OnJobCompletedThunk(GtkPrintJob* print_job,
                                         gpointer user_data,
                                         GError* error) {
  static_cast<PrintDialogGtk*>(user_data)->OnJobCompleted(print_job, error);
}

void PrintDialogGtk::OnJobCompleted(GtkPrintJob* print_job, GError* error) {
  if (error)
    LOG(ERROR) << "Printing failed: " << error->message;
  if (print_job)
    g_object_unref(print_job);
  base::FileUtilProxy::Delete(
      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE),
      path_to_pdf_,
      false,
      NULL);
  // Printing finished. Matches AddRef() in PrintDocument();
  Release();
}

void PrintDialogGtk::InitPrintSettings(const PageRanges& page_ranges) {
  PrintSettings settings;
  printing::PrintSettingsInitializerGtk::InitPrintSettings(
      gtk_settings_, page_setup_, page_ranges, false, &settings);
  context_->InitWithSettings(settings);
}