// Copyright (c) 2012 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 "ui/views/examples/text_example.h"

#include <memory>

#include "base/stl_util.h"
#include "base/strings/utf_string_conversions.h"
#include "ui/gfx/canvas.h"
#include "ui/gfx/font_list.h"
#include "ui/views/border.h"
#include "ui/views/controls/button/checkbox.h"
#include "ui/views/controls/combobox/combobox.h"
#include "ui/views/controls/label.h"
#include "ui/views/examples/example_combobox_model.h"
#include "ui/views/layout/grid_layout.h"
#include "ui/views/view.h"

namespace views {
namespace examples {

namespace {

// Number of columns in the view layout.
const int kNumColumns = 10;

const char kShortText[] = "The quick brown fox jumps over the lazy dog.";
const char kLongText[] =
    "Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod "
    "tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim "
    "veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea "
    "commodo consequat.\nDuis aute irure dolor in reprehenderit in voluptate "
    "velit esse cillum dolore eu fugiat nulla pariatur.\n\nExcepteur sint "
    "occaecat cupidatat non proident, sunt in culpa qui officia deserunt "
    "mollit anim id est laborum.";
const char kAmpersandText[] =
    "The quick && &brown fo&x jumps over the lazy dog.";
const wchar_t kRightToLeftText[] =
    L"\x5e9\x5dc\x5d5\x5dd \x5d4\x5e2\x5d5\x5dc\x5dd! "
    L"\x5e9\x5dc\x5d5\x5dd \x5d4\x5e2\x5d5\x5dc\x5dd! "
    L"\x5e9\x5dc\x5d5\x5dd \x5d4\x5e2\x5d5\x5dc\x5dd! "
    L"\x5e9\x5dc\x5d5\x5dd \x5d4\x5e2\x5d5\x5dc\x5dd! "
    L"\x5e9\x5dc\x5d5\x5dd \x5d4\x5e2\x5d5\x5dc\x5dd! "
    L"\x5e9\x5dc\x5d5\x5dd \x5d4\x5e2\x5d5\x5dc\x5dd! "
    L"\x5e9\x5dc\x5d5\x5dd \x5d4\x5e2\x5d5\x5dc\x5dd! "
    L"\x5e9\x5dc\x5d5\x5dd \x5d4\x5e2\x5d5\x5dc\x5dd!";

const char* kTextExamples[] = { "Short", "Long", "Ampersands", "RTL Hebrew", };
const char* kElideBehaviors[] = { "Elide", "No Elide", "Fade", };
const char* kPrefixOptions[] = { "Default", "Show", "Hide", };
const char* kHorizontalAligments[] = { "Default", "Left", "Center", "Right", };
constexpr const char* kWeightLabels[] = {
    "Thin",     "Extra Light", "Light",      "Normal", "Medium",
    "Semibold", "Bold",        "Extra Bold", "Black",
};
constexpr gfx::Font::Weight kFontWeights[]{
    gfx::Font::Weight::THIN,   gfx::Font::Weight::EXTRA_LIGHT,
    gfx::Font::Weight::LIGHT,  gfx::Font::Weight::NORMAL,
    gfx::Font::Weight::MEDIUM, gfx::Font::Weight::SEMIBOLD,
    gfx::Font::Weight::BOLD,   gfx::Font::Weight::EXTRA_BOLD,
    gfx::Font::Weight::BLACK,
};

// Toggles bit |flag| on |flags| based on state of |checkbox|.
void SetFlagFromCheckbox(Checkbox* checkbox, int* flags, int flag) {
  if (checkbox->checked())
    *flags |= flag;
  else
    *flags &= ~flag;
}

}  // namespace

// TextExample's content view, which draws stylized string.
class TextExample::TextExampleView : public View {
 public:
  TextExampleView()
    : text_(base::ASCIIToUTF16(kShortText)),
      flags_(0),
      elide_(gfx::NO_ELIDE) {
  }

  void OnPaint(gfx::Canvas* canvas) override {
    View::OnPaint(canvas);
    const gfx::Rect bounds = GetContentsBounds();
    const SkColor color = SK_ColorDKGRAY;
    if (elide_ == gfx::FADE_TAIL) {
      canvas->DrawFadedString(text_, font_list_, color, bounds, flags_);
    } else {
      canvas->DrawStringRectWithFlags(text_, font_list_, color, bounds, flags_);
    }
  }

  int flags() const { return flags_; }
  void set_flags(int flags) { flags_ = flags; }
  void set_text(const base::string16& text) { text_ = text; }
  void set_elide(gfx::ElideBehavior elide) { elide_ = elide; }

  int GetStyle() const { return font_list_.GetFontStyle(); }
  void SetStyle(int style) {
    base_font_ = base_font_.DeriveWithStyle(style);
    font_list_ = font_list_.DeriveWithStyle(style);
  }

  gfx::Font::Weight GetWeight() const { return font_list_.GetFontWeight(); }
  void SetWeight(gfx::Font::Weight weight) {
    font_list_ = base_font_.DeriveWithWeight(weight);
  }

 private:
  // The font used for drawing the text.
  gfx::FontList font_list_;

  // The font without any bold attributes. Mac font APIs struggle to derive UI
  // fonts from a base font that isn't NORMAL or BOLD.
  gfx::FontList base_font_;

  // The text to draw.
  base::string16 text_;

  // Text flags for passing to |DrawStringRect()|.
  int flags_;

  // The eliding, fading, or truncating behavior.
  gfx::ElideBehavior elide_;

  DISALLOW_COPY_AND_ASSIGN(TextExampleView);
};

TextExample::TextExample() : ExampleBase("Text Styles") {}

TextExample::~TextExample() = default;

Checkbox* TextExample::AddCheckbox(GridLayout* layout, const char* name) {
  Checkbox* checkbox = new Checkbox(base::ASCIIToUTF16(name), this);
  layout->AddView(checkbox);
  return checkbox;
}

Combobox* TextExample::AddCombobox(GridLayout* layout,
                                   const char* name,
                                   const char* const* strings,
                                   int count) {
  layout->StartRow(0, 0);
  layout->AddView(new Label(base::ASCIIToUTF16(name)));
  Combobox* combobox =
      new Combobox(std::make_unique<ExampleComboboxModel>(strings, count));
  combobox->SetSelectedIndex(0);
  combobox->set_listener(this);
  layout->AddView(combobox, kNumColumns - 1, 1);
  return combobox;
}

void TextExample::CreateExampleView(View* container) {
  text_view_ = new TextExampleView;
  text_view_->SetBorder(CreateSolidBorder(1, SK_ColorGRAY));
  GridLayout* layout = container->SetLayoutManager(
      std::make_unique<views::GridLayout>(container));
  layout->AddPaddingRow(0, 8);

  ColumnSet* column_set = layout->AddColumnSet(0);
  column_set->AddPaddingColumn(0, 8);
  column_set->AddColumn(GridLayout::LEADING, GridLayout::FILL,
                        0.1f, GridLayout::USE_PREF, 0, 0);
  for (int i = 0; i < kNumColumns - 1; i++)
    column_set->AddColumn(GridLayout::FILL, GridLayout::FILL,
                          0.1f, GridLayout::USE_PREF, 0, 0);
  column_set->AddPaddingColumn(0, 8);

  h_align_cb_ = AddCombobox(layout, "H-Align", kHorizontalAligments,
                            base::size(kHorizontalAligments));
  eliding_cb_ = AddCombobox(layout, "Eliding", kElideBehaviors,
                            base::size(kElideBehaviors));
  prefix_cb_ =
      AddCombobox(layout, "Prefix", kPrefixOptions, base::size(kPrefixOptions));
  text_cb_ = AddCombobox(layout, "Example Text", kTextExamples,
                         base::size(kTextExamples));
  weight_cb_ = AddCombobox(layout, "Font Weight", kWeightLabels,
                           base::size(kWeightLabels));
  weight_cb_->SelectValue(base::ASCIIToUTF16("Normal"));

  layout->StartRow(0, 0);
  multiline_checkbox_ = AddCheckbox(layout, "Multiline");
  break_checkbox_ = AddCheckbox(layout, "Character Break");
  italic_checkbox_ = AddCheckbox(layout, "Italic");
  underline_checkbox_ = AddCheckbox(layout, "Underline");

  layout->AddPaddingRow(0, 20);
  column_set = layout->AddColumnSet(1);
  column_set->AddPaddingColumn(0, 16);
  column_set->AddColumn(GridLayout::FILL, GridLayout::FILL,
                        1, GridLayout::USE_PREF, 0, 0);
  column_set->AddPaddingColumn(0, 16);
  layout->StartRow(1, 1);
  layout->AddView(text_view_);
  layout->AddPaddingRow(0, 8);
}

void TextExample::ButtonPressed(Button* button, const ui::Event& event) {
  int flags = text_view_->flags();
  int style = text_view_->GetStyle();
  SetFlagFromCheckbox(multiline_checkbox_, &flags, gfx::Canvas::MULTI_LINE);
  SetFlagFromCheckbox(break_checkbox_, &flags,
                      gfx::Canvas::CHARACTER_BREAKABLE);
  SetFlagFromCheckbox(italic_checkbox_, &style, gfx::Font::ITALIC);
  SetFlagFromCheckbox(underline_checkbox_, &style, gfx::Font::UNDERLINE);
  text_view_->set_flags(flags);
  text_view_->SetStyle(style);
  text_view_->SchedulePaint();
}

void TextExample::OnPerformAction(Combobox* combobox) {
  int flags = text_view_->flags();
  if (combobox == h_align_cb_) {
    flags &= ~(gfx::Canvas::TEXT_ALIGN_LEFT |
               gfx::Canvas::TEXT_ALIGN_CENTER |
               gfx::Canvas::TEXT_ALIGN_RIGHT);
    switch (combobox->selected_index()) {
      case 0:
        break;
      case 1:
        flags |= gfx::Canvas::TEXT_ALIGN_LEFT;
        break;
      case 2:
        flags |= gfx::Canvas::TEXT_ALIGN_CENTER;
        break;
      case 3:
        flags |= gfx::Canvas::TEXT_ALIGN_RIGHT;
        break;
    }
  } else if (combobox == text_cb_) {
    switch (combobox->selected_index()) {
      case 0:
        text_view_->set_text(base::ASCIIToUTF16(kShortText));
        break;
      case 1:
        text_view_->set_text(base::ASCIIToUTF16(kLongText));
        break;
      case 2:
        text_view_->set_text(base::ASCIIToUTF16(kAmpersandText));
        break;
      case 3:
        text_view_->set_text(base::WideToUTF16(kRightToLeftText));
        break;
    }
  } else if (combobox == eliding_cb_) {
    switch (combobox->selected_index()) {
      case 0:
        text_view_->set_elide(gfx::ELIDE_TAIL);
        break;
      case 1:
        text_view_->set_elide(gfx::NO_ELIDE);
        break;
      case 2:
        text_view_->set_elide(gfx::FADE_TAIL);
        break;
    }
  } else if (combobox == prefix_cb_) {
    flags &= ~(gfx::Canvas::SHOW_PREFIX | gfx::Canvas::HIDE_PREFIX);
    switch (combobox->selected_index()) {
      case 0:
        break;
      case 1:
        flags |= gfx::Canvas::SHOW_PREFIX;
        break;
      case 2:
        flags |= gfx::Canvas::HIDE_PREFIX;
        break;
    }
  } else if (combobox == weight_cb_) {
    text_view_->SetWeight(kFontWeights[combobox->selected_index()]);
  }
  text_view_->set_flags(flags);
  text_view_->SchedulePaint();
}

}  // namespace examples
}  // namespace views