// Copyright 2009 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include <cstddef>
#include <mutex>
#include <queue>
#include <utility>
#include <vector>
#include <wx/aui/framemanager.h>
#include <wx/button.h>
#include <wx/checkbox.h>
#include <wx/choice.h>
#include <wx/colour.h>
#include <wx/font.h>
#include <wx/panel.h>
#include <wx/sizer.h>
#include <wx/textctrl.h>
#include <wx/timer.h>
#include <wx/validate.h>

#include "Common/CommonTypes.h"
#include "Common/FileUtil.h"
#include "Common/IniFile.h"
#include "Common/Logging/ConsoleListener.h"
#include "Common/Logging/LogManager.h"
#include "DolphinWX/Debugger/DebuggerUIUtil.h"
#include "DolphinWX/Frame.h"
#include "DolphinWX/LogWindow.h"
#include "DolphinWX/WxUtils.h"

// Milliseconds between msgQueue flushes to wxTextCtrl
constexpr int UPDATE_TIME_MS = 200;
// Max size of msgQueue, old messages will be discarded when there are too many.
constexpr size_t MSGQUEUE_MAX_SIZE = 100;

CLogWindow::CLogWindow(CFrame* parent, wxWindowID id, const wxPoint& pos, const wxSize& size,
                       long style, const wxString& name)
    : wxPanel(parent, id, pos, size, style, name), x(0), y(0), winpos(0), Parent(parent),
      m_LogAccess(true), m_Log(nullptr), m_cmdline(nullptr), m_FontChoice(nullptr)
{
  Bind(wxEVT_TIMER, &CLogWindow::OnLogTimer, this);

  m_LogManager = LogManager::GetInstance();
  m_LogManager->RegisterListener(LogListener::LOG_WINDOW_LISTENER, this);

  CreateGUIControls();

  m_LogTimer.SetOwner(this);
  m_LogTimer.Start(UPDATE_TIME_MS);
}

void CLogWindow::CreateGUIControls()
{
  IniFile ini;
  ini.Load(File::GetUserPath(F_LOGGERCONFIG_IDX));

  IniFile::Section* options = ini.GetOrCreateSection("Options");
  IniFile::Section* log_window = ini.GetOrCreateSection("LogWindow");
  log_window->Get("x", &x, Parent->GetSize().GetX() / 2);
  log_window->Get("y", &y, Parent->GetSize().GetY());
  log_window->Get("pos", &winpos, wxAUI_DOCK_RIGHT);

  // Font
  m_FontChoice = new wxChoice(this, wxID_ANY);
  m_FontChoice->Bind(wxEVT_CHOICE, &CLogWindow::OnFontChange, this);
  m_FontChoice->Append(_("Default font"));
  m_FontChoice->Append(_("Monospaced font"));
  m_FontChoice->Append(_("Selected font"));

  DefaultFont = GetFont();
  MonoSpaceFont.SetFamily(wxFONTFAMILY_TELETYPE);
#ifdef _WIN32
  // Windows uses Courier New for monospace even though there are better fonts.
  MonoSpaceFont.SetFaceName("Consolas");
#endif
  MonoSpaceFont.SetPointSize(DefaultFont.GetPointSize());
  LogFont.push_back(DefaultFont);
  LogFont.push_back(MonoSpaceFont);
  LogFont.push_back(DebuggerFont);

  int font;
  options->Get("Font", &font, 0);
  m_FontChoice->SetSelection(font);

  // Word wrap
  bool wrap_lines;
  options->Get("WrapLines", &wrap_lines, false);
  m_WrapLine = new wxCheckBox(this, wxID_ANY, _("Word Wrap"));
  m_WrapLine->Bind(wxEVT_CHECKBOX, &CLogWindow::OnWrapLineCheck, this);
  m_WrapLine->SetValue(wrap_lines);

  // Log viewer
  m_Log = CreateTextCtrl(this, wxID_ANY, wxTE_RICH | wxTE_MULTILINE | wxTE_READONLY |
                                             (wrap_lines ? wxTE_WORDWRAP : wxTE_DONTWRAP));

  // submit row
  m_cmdline = new wxTextCtrl(this, wxID_ANY, wxEmptyString, wxDefaultPosition, wxDefaultSize,
                             wxTE_PROCESS_ENTER | wxTE_PROCESS_TAB);

  // Clear log button
  m_clear_log_btn =
      new wxButton(this, wxID_ANY, _("Clear"), wxDefaultPosition, wxDefaultSize, wxBU_EXACTFIT);
  m_clear_log_btn->Bind(wxEVT_BUTTON, &CLogWindow::OnClear, this);

  const int space3 = FromDIP(3);

  // Sizers
  wxBoxSizer* sTop = new wxBoxSizer(wxHORIZONTAL);
  sTop->Add(m_clear_log_btn, 0, wxALIGN_CENTER_VERTICAL);
  sTop->Add(m_FontChoice, 0, wxALIGN_CENTER_VERTICAL | wxLEFT, space3);
  sTop->Add(m_WrapLine, 0, wxALIGN_CENTER_VERTICAL | wxLEFT, space3);

  sBottom = new wxBoxSizer(wxVERTICAL);
  PopulateBottom();

  wxBoxSizer* sMain = new wxBoxSizer(wxVERTICAL);
  sMain->Add(sTop, 0, wxEXPAND);
  sMain->Add(sBottom, 1, wxEXPAND);
  SetSizer(sMain);

  m_cmdline->SetFocus();
}

CLogWindow::~CLogWindow()
{
  RemoveAllListeners();
}

void CLogWindow::RemoveAllListeners()
{
  if (!m_has_listeners)
    return;
  m_has_listeners = false;

  for (int i = 0; i < LogTypes::NUMBER_OF_LOGS; ++i)
  {
    m_LogManager->RemoveListener(static_cast<LogTypes::LOG_TYPE>(i),
                                 LogListener::LOG_WINDOW_LISTENER);
  }
}

void CLogWindow::SaveSettings()
{
  IniFile ini;
  ini.Load(File::GetUserPath(F_LOGGERCONFIG_IDX));

  if (!Parent->m_code_window)
  {
    IniFile::Section* log_window = ini.GetOrCreateSection("LogWindow");
    log_window->Set("x", x);
    log_window->Set("y", y);
    log_window->Set("pos", winpos);
  }

  IniFile::Section* options = ini.GetOrCreateSection("Options");
  options->Set("Font", m_FontChoice->GetSelection());
  options->Set("WrapLines", m_WrapLine->IsChecked());

  ini.Save(File::GetUserPath(F_LOGGERCONFIG_IDX));
}

void CLogWindow::OnClear(wxCommandEvent& WXUNUSED(event))
{
  m_Log->Clear();

  {
    std::lock_guard<std::mutex> lk(m_LogSection);
    while (!msgQueue.empty())
      msgQueue.pop();
  }
}

void CLogWindow::UnPopulateBottom()
{
  sBottom->Detach(m_Log);
  sBottom->Detach(m_cmdline);
}

void CLogWindow::PopulateBottom()
{
  sBottom->Add(m_Log, 1, wxEXPAND | wxSHRINK);
  sBottom->Add(m_cmdline, 0, wxEXPAND);
  Layout();
}

wxTextCtrl* CLogWindow::CreateTextCtrl(wxPanel* parent, wxWindowID id, long Style)
{
  wxTextCtrl* TC =
      new wxTextCtrl(parent, id, wxEmptyString, wxDefaultPosition, wxDefaultSize, Style);
#ifdef __APPLE__
  TC->SetBackgroundColour(*wxLIGHT_GREY);
#else
  TC->SetBackgroundColour(*wxBLACK);
#endif
  if (m_FontChoice && m_FontChoice->GetSelection() < (int)LogFont.size() &&
      m_FontChoice->GetSelection() >= 0)
    TC->SetDefaultStyle(
        wxTextAttr(wxNullColour, wxNullColour, LogFont[m_FontChoice->GetSelection()]));

  return TC;
}

void CLogWindow::OnFontChange(wxCommandEvent& event)
{
  // Update selected font
  LogFont[LogFont.size() - 1] = DebuggerFont;
  m_Log->SetStyle(0, m_Log->GetLastPosition(),
                  wxTextAttr(wxNullColour, wxNullColour, LogFont[event.GetSelection()]));
  m_Log->SetDefaultStyle(wxTextAttr(wxNullColour, wxNullColour, LogFont[event.GetSelection()]));

  SaveSettings();
}

void CLogWindow::OnWrapLineCheck(wxCommandEvent& event)
{
#ifdef __WXGTK__
  // Clear the old word wrap state and set the new
  m_Log->SetWindowStyleFlag(m_Log->GetWindowStyleFlag() ^ (wxTE_WORDWRAP | wxTE_DONTWRAP));
#else
  wxString Text;
  // Unfortunately wrapping styles can only be changed dynamically with wxGTK
  // Notice: To retain the colors when changing word wrapping we need to
  //         loop through every letter with GetStyle and then reapply them letter by letter
  // Prevent m_Log access while it's being destroyed
  m_LogAccess = false;
  UnPopulateBottom();
  Text = m_Log->GetValue();
  m_Log->Destroy();
  if (event.IsChecked())
    m_Log =
        CreateTextCtrl(this, wxID_ANY, wxTE_RICH | wxTE_MULTILINE | wxTE_READONLY | wxTE_WORDWRAP);
  else
    m_Log =
        CreateTextCtrl(this, wxID_ANY, wxTE_RICH | wxTE_MULTILINE | wxTE_READONLY | wxTE_DONTWRAP);
  m_Log->SetDefaultStyle(wxTextAttr(*wxWHITE));
  m_Log->AppendText(Text);
  PopulateBottom();
  m_LogAccess = true;
#endif
  SaveSettings();
}

void CLogWindow::OnLogTimer(wxTimerEvent& WXUNUSED(event))
{
  if (!m_LogAccess)
    return;

  UpdateLog();

  // Scroll to the last line
  if (!msgQueue.empty())
  {
    m_Log->ScrollLines(1);
    m_Log->ShowPosition(m_Log->GetLastPosition());
  }
}

void CLogWindow::UpdateLog()
{
  if (!m_LogAccess || !m_Log || msgQueue.empty())
    return;

  m_LogTimer.Stop();

  // This function runs on the main gui thread, and needs to finish in a finite time otherwise
  // the GUI will lock up, which could be an issue if new messages are flooding in faster than
  // this function can render them to the screen.
  // So we limit this function to processing MSGQUEUE_MAX_SIZE messages each time it's called.
  for (size_t num = 0; num < MSGQUEUE_MAX_SIZE; num++)
  {
    u8 log_level;
    wxString log_msg;

    // We can't hold this mutex while calling Wx functions, due to deadlocks
    {
      std::lock_guard<std::mutex> lk(m_LogSection);

      if (msgQueue.empty())
        break;

      log_level = msgQueue.front().first;
      log_msg = std::move(msgQueue.front().second);
      msgQueue.pop();
    }

    switch (log_level)
    {
    case LogTypes::LOG_LEVELS::LERROR:
      m_Log->SetDefaultStyle(wxTextAttr(*wxRED));
      break;

    case LogTypes::LOG_LEVELS::LWARNING:
      m_Log->SetDefaultStyle(wxTextAttr(*wxYELLOW));
      break;

    case LogTypes::LOG_LEVELS::LNOTICE:
      m_Log->SetDefaultStyle(wxTextAttr(*wxGREEN));
      break;

    case LogTypes::LOG_LEVELS::LINFO:
      m_Log->SetDefaultStyle(wxTextAttr(*wxCYAN));
      break;

    case LogTypes::LOG_LEVELS::LDEBUG:
      m_Log->SetDefaultStyle(wxTextAttr(*wxLIGHT_GREY));
      break;

    default:
      m_Log->SetDefaultStyle(wxTextAttr(*wxWHITE));
      break;
    }

    if (log_msg.size())
    {
      int i = m_Log->GetLastPosition();
      m_Log->AppendText(log_msg);
      // White timestamp
      m_Log->SetStyle(i, i + 9, wxTextAttr(*wxWHITE));
    }
  }

  m_LogTimer.Start();
}

void CLogWindow::Log(LogTypes::LOG_LEVELS level, const char* text)
{
  std::lock_guard<std::mutex> lk(m_LogSection);

  if (msgQueue.size() >= MSGQUEUE_MAX_SIZE)
    msgQueue.pop();

  msgQueue.emplace(static_cast<u8>(level), StrToWxStr(text));
}