/*
 * Copyright (c) 2023 Samsung Electronics Co., Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

//------------------------------------------------------------------------------
//
//
//------------------------------------------------------------------------------

#include <dali-toolkit/dali-toolkit.h>
#include <dali-toolkit/devel-api/builder/builder.h>
#include <dali-toolkit/devel-api/builder/json-parser.h>
#include <dali-toolkit/devel-api/builder/tree-node.h>
#include <dali-toolkit/devel-api/controls/navigation-view/navigation-view.h>
#include <dali-toolkit/devel-api/controls/popup/popup.h>
#include <dali/dali.h>

#include <dirent.h>
#include <stdio.h>
#include <fstream>
#include <iostream>
#include <map>
#include <sstream>
#include <streambuf>
#include <string>

#include <cstring>
#include <ctime>
#include "sys/stat.h"

#include <dali/devel-api/adaptor-framework/file-loader.h>
#include <dali/integration-api/debug.h>
#include "shared/view.h"

#define TOKEN_STRING(x) #x

using namespace Dali;
using namespace Dali::Toolkit;

namespace
{
const char* BACKGROUND_IMAGE("");
const char* TOOLBAR_IMAGE(DEMO_IMAGE_DIR "top-bar.png");
const char* EDIT_IMAGE(DEMO_IMAGE_DIR "icon-change.png");
const char* EDIT_IMAGE_SELECTED(DEMO_IMAGE_DIR "icon-change-selected.png");

std::string USER_DIRECTORY;

std::string JSON_BROKEN(
  "                                      \
{                                                              \
  'stage':                                                     \
  [                                                            \
    {                                                          \
      'type':'TextLabel',                                      \
      'size': [50,50,1],                                       \
      'parentOrigin': 'CENTER',                                \
      'text':'COULD NOT LOAD JSON FILE'                        \
    }                                                          \
  ]                                                            \
}                                                              \
");

std::string ReplaceQuotes(const std::string& single_quoted)
{
  std::string s(single_quoted);

  // wrong as no embedded quote but had regex link problems
  std::replace(s.begin(), s.end(), '\'', '"');

  return s;
}

std::string GetFileContents(const std::string& fn)
{
  std::streampos     bufferSize = 0;
  Dali::Vector<char> fileBuffer;
  if(!Dali::FileLoader::ReadFile(fn, bufferSize, fileBuffer, FileLoader::FileType::BINARY))
  {
    return std::string();
  }

  return std::string(&fileBuffer[0], bufferSize);
};

typedef std::vector<std::string> FileList;

void DirectoryFileList(const std::string& directory, FileList& files)
{
  DIR*           d;
  struct dirent* dir;
  d = opendir(directory.c_str());
  if(d)
  {
    while((dir = readdir(d)) != NULL)
    {
      if(dir->d_type == DT_REG)
      {
        files.push_back(directory + std::string(dir->d_name));
      }
    }

    closedir(d);
  }
}

void DirectoryFilesByType(const std::string& dir, const std::string& fileType /* ie "json" */, FileList& files)
{
  typedef FileList           Collection;
  typedef FileList::iterator Iter;

  Collection allFiles;
  DirectoryFileList(dir, allFiles);

  for(Iter iter = allFiles.begin(); iter != allFiles.end(); ++iter)
  {
    size_t pos = (*iter).rfind('.');
    if(pos != std::string::npos)
    {
      if((*iter).substr(pos + 1) == fileType)
      {
        files.push_back((*iter));
      }
    }
  }
}

const std::string ShortName(const std::string& name)
{
  size_t pos = name.rfind('/');

  if(pos != std::string::npos)
  {
    pos++;
    return name.substr(pos);
  }
  else
  {
    return name;
  }
}

//------------------------------------------------------------------------------
//
//
//
//------------------------------------------------------------------------------
class FileWatcher
{
public:
  FileWatcher(void);
  ~FileWatcher(void);
  explicit FileWatcher(const std::string& fn)
  : mLastTime(0),
    mstringPath{}
  {
    SetFilename(fn);
  };

  void        SetFilename(const std::string& fn);
  std::string GetFilename() const;

  bool        FileHasChanged(void);
  std::string GetFileContents(void) const
  {
    return ::GetFileContents(mstringPath);
  };

private:
  // compiler does
  // FileWatcher(const FileWatcher&);
  // FileWatcher &operator=(const FileWatcher &);

  std::time_t mLastTime;
  std::string mstringPath;
};

FileWatcher::FileWatcher(void)
: mLastTime(0),
  mstringPath{}
{
}

bool FileWatcher::FileHasChanged(void)
{
  struct stat buf;

  if(0 != stat(mstringPath.c_str(), &buf))
  {
    return false;
  }
  else
  {
    const bool result = buf.st_mtime > mLastTime;
    mLastTime         = std::time_t(buf.st_mtime);
    return result;
  }

  return false;
}

FileWatcher::~FileWatcher()
{
}

void FileWatcher::SetFilename(const std::string& fn)
{
  mstringPath = fn;
  FileHasChanged(); // update last time
}

std::string FileWatcher::GetFilename(void) const
{
  return mstringPath;
}

} // namespace

//------------------------------------------------------------------------------
//
//
//
//------------------------------------------------------------------------------
class ExampleApp : public ConnectionTracker, public Toolkit::ItemFactory
{
public:
  ExampleApp(Application& app)
  : mApp(app)
  {
    app.InitSignal().Connect(this, &ExampleApp::Create);
  }

  ~ExampleApp()
  {
  }

public:
  void SetTitle(const std::string& title)
  {
    if(!mTitleActor)
    {
      mTitleActor = DemoHelper::CreateToolBarLabel("");
      // Add title to the tool bar.
      mToolBar.AddControl(mTitleActor, DemoHelper::DEFAULT_VIEW_STYLE.mToolBarTitlePercentage, Alignment::HORIZONTAL_CENTER);
    }

    mTitleActor.SetProperty(TextLabel::Property::TEXT, title);
  }

  bool OnBackButtonPressed(Toolkit::Button button)
  {
    OnQuitOrBack();
    return true;
  }

  void SetUpItemView()
  {
    Window window = mApp.GetWindow();

    mTapDetector = TapGestureDetector::New();
    mTapDetector.DetectedSignal().Connect(this, &ExampleApp::OnTap);

    mFiles.clear();

    mItemView = ItemView::New(*this);

    mItemView.SetProperty(Actor::Property::PARENT_ORIGIN, ParentOrigin::CENTER);
    mItemView.SetProperty(Actor::Property::ANCHOR_POINT, AnchorPoint::CENTER);
    mLayout = DefaultItemLayout::New(DefaultItemLayout::LIST);

    mLayout->SetItemSize(Vector3(window.GetSize().GetWidth(), 50, 1));

    mItemView.AddLayout(*mLayout);

    mItemView.SetProperty(Actor::Property::KEYBOARD_FOCUSABLE, true);

    mFiles.clear();
    FileList files;

    if(USER_DIRECTORY.size())
    {
      DirectoryFilesByType(USER_DIRECTORY, "json", files);
    }
    else
    {
      DirectoryFilesByType(DEMO_SCRIPT_DIR, "json", files);
    }

    std::sort(files.begin(), files.end());

    for(FileList::iterator iter = files.begin(); iter != files.end(); ++iter)
    {
      JsonParser parser = JsonParser::New();

      std::string data(GetFileContents(*iter));

      parser.Parse(data);

      if(parser.ParseError())
      {
        std::cout << "Parser Error:" << *iter << std::endl;
        std::cout << parser.GetErrorLineNumber() << "(" << parser.GetErrorColumn() << "):" << parser.GetErrorDescription() << std::endl;
        exit(1);
      }

      if(parser.GetRoot())
      {
        if(const TreeNode* node = parser.GetRoot()->Find("stage"))
        {
          // only those with a stage section
          if(node->Size())
          {
            mFiles.push_back(*iter);
          }
          else
          {
            std::cout << "Ignored file (stage has no nodes?):" << *iter << std::endl;
          }
        }
        else
        {
          std::cout << "Ignored file (no stage section):" << *iter << std::endl;
        }
      }
    }

    // Activate the layout
    Vector3 size(window.GetSize());
    mItemView.ActivateLayout(0, size, 0.0f /*immediate*/);
  }

  void OnTap(Actor actor, const TapGesture& tap)
  {
    ItemId id = mItemView.GetItemId(actor);

    LoadFromFileList(id);
  }

  Actor MenuItem(const std::string& text)
  {
    TextLabel label = TextLabel::New(ShortName(text));
    label.SetStyleName("BuilderLabel");
    label.SetResizePolicy(ResizePolicy::FILL_TO_PARENT, Dimension::WIDTH);

    // Hook up tap detector
    mTapDetector.Attach(label);

    return label;
  }

  bool OnTimer()
  {
    if(mFileWatcher.FileHasChanged())
    {
      LoadFromFile(mFileWatcher.GetFilename());
    }

    return true;
  }

  void ReloadJsonFile(const std::string& filename, Builder& builder, Layer& layer)
  {
    Window window = mApp.GetWindow();

    builder = Builder::New();
    builder.QuitSignal().Connect(this, &ExampleApp::OnQuitOrBack);

    Property::Map defaultDirs;
    defaultDirs[TOKEN_STRING(DEMO_IMAGE_DIR)]  = DEMO_IMAGE_DIR;
    defaultDirs[TOKEN_STRING(DEMO_MODEL_DIR)]  = DEMO_MODEL_DIR;
    defaultDirs[TOKEN_STRING(DEMO_SCRIPT_DIR)] = DEMO_SCRIPT_DIR;

    builder.AddConstants(defaultDirs);

    // render tasks may have been setup last load so remove them
    RenderTaskList taskList = window.GetRenderTaskList();
    if(taskList.GetTaskCount() > 1)
    {
      typedef std::vector<RenderTask> Collection;
      typedef Collection::iterator    ColIter;
      Collection                      tasks;

      for(unsigned int i = 1; i < taskList.GetTaskCount(); ++i)
      {
        tasks.push_back(taskList.GetTask(i));
      }

      for(ColIter iter = tasks.begin(); iter != tasks.end(); ++iter)
      {
        taskList.RemoveTask(*iter);
      }

      RenderTask defaultTask = taskList.GetTask(0);
      defaultTask.SetSourceActor(window.GetRootLayer());
      defaultTask.SetFrameBuffer(FrameBuffer());
    }

    unsigned int numChildren = layer.GetChildCount();

    for(unsigned int i = 0; i < numChildren; ++i)
    {
      layer.Remove(layer.GetChildAt(0));
    }

    std::string data(GetFileContents(filename));

    try
    {
      builder.LoadFromString(data);
    }
    catch(...)
    {
      builder.LoadFromString(ReplaceQuotes(JSON_BROKEN));
    }

    builder.AddActors(layer);
  }

  void LoadFromFileList(size_t index)
  {
    if(index < mFiles.size())
    {
      const std::string& name = mFiles[index];
      mFileWatcher.SetFilename(name);
      LoadFromFile(name);
    }
  }

  void LoadFromFile(const std::string& name)
  {
    ReloadJsonFile(name, mBuilder, mBuilderLayer);

    mBuilderLayer.SetProperty(Actor::Property::PARENT_ORIGIN, ParentOrigin::BOTTOM_CENTER);
    mBuilderLayer.SetProperty(Actor::Property::ANCHOR_POINT, AnchorPoint::BOTTOM_CENTER);
    Dali::Vector3 size = mApp.GetWindow().GetRootLayer().GetCurrentProperty<Vector3>(Actor::Property::SIZE);
    size.y -= DemoHelper::DEFAULT_VIEW_STYLE.mToolBarHeight;
    mBuilderLayer.SetProperty(Actor::Property::SIZE, size);

    mNavigationView.Push(mBuilderLayer);
  }

  void Create(Application& app)
  {
    Window window = app.GetWindow();

    window.KeyEventSignal().Connect(this, &ExampleApp::OnKeyEvent);

    Layer contents = DemoHelper::CreateView(app,
                                            mView,
                                            mToolBar,
                                            BACKGROUND_IMAGE,
                                            TOOLBAR_IMAGE,
                                            "");

    SetTitle("Select Example");

    mBuilderLayer = Layer::New();

    // Create an edit mode button. (left of toolbar)
    Toolkit::PushButton backButton = Toolkit::PushButton::New();
    backButton.SetProperty(Toolkit::Button::Property::UNSELECTED_BACKGROUND_VISUAL, EDIT_IMAGE);
    backButton.SetProperty(Toolkit::Button::Property::SELECTED_BACKGROUND_VISUAL, EDIT_IMAGE_SELECTED);
    backButton.ClickedSignal().Connect(this, &ExampleApp::OnBackButtonPressed);
    backButton.SetProperty(Actor::Property::LEAVE_REQUIRED, true);
    mToolBar.AddControl(backButton, DemoHelper::DEFAULT_VIEW_STYLE.mToolBarButtonPercentage, Toolkit::Alignment::HORIZONTAL_LEFT, DemoHelper::DEFAULT_MODE_SWITCH_PADDING);

    mNavigationView = Toolkit::NavigationView::New();
    mNavigationView.SetResizePolicy(ResizePolicy::FILL_TO_PARENT, Dimension::ALL_DIMENSIONS);
    mNavigationView.SetProperty(Actor::Property::ANCHOR_POINT, AnchorPoint::TOP_LEFT);

    window.Add(mNavigationView);

    // Set up the background gradient.
    Property::Array stopOffsets;
    stopOffsets.PushBack(0.0f);
    stopOffsets.PushBack(1.0f);
    Property::Array stopColors;
    stopColors.PushBack(Color::WHITE);
    stopColors.PushBack(Vector4(0.45f, 0.70f, 0.80f, 1.0f)); // Medium bright, pastel blue
    const float percentageWindowHeight = window.GetSize().GetHeight() * 0.6f;

    mNavigationView.SetProperty(Toolkit::Control::Property::BACKGROUND, Dali::Property::Map().Add(Toolkit::Visual::Property::TYPE, Dali::Toolkit::Visual::GRADIENT).Add(Toolkit::GradientVisual::Property::STOP_OFFSET, stopOffsets).Add(Toolkit::GradientVisual::Property::STOP_COLOR, stopColors).Add(Toolkit::GradientVisual::Property::START_POSITION, Vector2(0.0f, -percentageWindowHeight)).Add(Toolkit::GradientVisual::Property::END_POSITION, Vector2(0.0f, percentageWindowHeight)).Add(Toolkit::GradientVisual::Property::UNITS, Toolkit::GradientVisual::Units::USER_SPACE));

    SetUpItemView();
    mNavigationView.Push(mItemView);

    mTimer = Timer::New(500); // ms
    mTimer.TickSignal().Connect(this, &ExampleApp::OnTimer);
    mTimer.Start();

  } // Create(app)

  virtual unsigned int GetNumberOfItems()
  {
    return mFiles.size();
  }

  virtual Actor NewItem(unsigned int itemId)
  {
    DALI_ASSERT_DEBUG(itemId < mFiles.size());
    return MenuItem(ShortName(mFiles[itemId]));
  }

  /**
   * Main key event handler
   */
  void OnKeyEvent(const KeyEvent& event)
  {
    if(event.GetState() == KeyEvent::DOWN)
    {
      if(IsKey(event, Dali::DALI_KEY_ESCAPE) || IsKey(event, Dali::DALI_KEY_BACK))
      {
        OnQuitOrBack();
      }
    }
  }

  /**
   * Event handler when Builder wants to quit (we only want to close the shown json unless we're at the top-level)
   */
  void OnQuitOrBack()
  {
    if(mItemView.GetProperty<bool>(Actor::Property::CONNECTED_TO_SCENE))
    {
      mApp.Quit();
    }
    else
    {
      mNavigationView.Pop();
    }
  }

private:
  Application& mApp;

  ItemLayoutPtr           mLayout;
  ItemView                mItemView;
  Toolkit::NavigationView mNavigationView;

  Toolkit::Control mView;

  Toolkit::ToolBar mToolBar;
  TextLabel        mTitleActor;

  Layer mBuilderLayer;

  TapGestureDetector mTapDetector;

  // builder
  Builder mBuilder;

  FileList mFiles;

  FileWatcher mFileWatcher;
  Timer       mTimer;
};

//------------------------------------------------------------------------------
//
//
//
//------------------------------------------------------------------------------
int DALI_EXPORT_API main(int argc, char** argv)
{
  if(argc > 2)
  {
    if(strcmp(argv[1], "-f") == 0)
    {
      USER_DIRECTORY = argv[2];
    }
  }

  Application app = Application::New(&argc, &argv, DEMO_THEME_PATH);

  ExampleApp dali_app(app);

  app.MainLoop();

  return 0;
}