// Copyright 2014 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include <algorithm>
#include <array>
#include <cstring>
#include <wx/arrstr.h>
#include <wx/button.h>
#include <wx/choice.h>
#include <wx/listctrl.h>
#include <wx/panel.h>
#include <wx/radiobox.h>
#include <wx/radiobut.h>
#include <wx/sizer.h>
#include <wx/stattext.h>
#include <wx/textctrl.h>
#include <wx/timer.h>

#include "Common/CommonFuncs.h"
#include "Common/CommonTypes.h"
#include "Common/StringUtil.h"
#include "Core/ActionReplay.h"
#include "Core/Core.h"
#include "Core/HW/Memmap.h"
#include "DolphinWX/Cheats/CheatSearchTab.h"
#include "DolphinWX/Cheats/CreateCodeDialog.h"
#include "DolphinWX/WxUtils.h"

static constexpr unsigned int MAX_CHEAT_SEARCH_RESULTS_DISPLAY = 1024;

CheatSearchTab::CheatSearchTab(wxWindow* const parent) : wxPanel(parent)
{
  m_update_timer.SetOwner(this);
  Bind(wxEVT_TIMER, &CheatSearchTab::OnTimerUpdate, this);

  // first scan button
  m_btn_init_scan = new wxButton(this, wxID_ANY, _("New Scan"));
  m_btn_init_scan->SetToolTip(_("Perform a full index of the game's RAM at the current Data Size. "
                                "Required before any Searching can be performed."));
  m_btn_init_scan->Bind(wxEVT_BUTTON, &CheatSearchTab::OnNewScanClicked, this);
  m_btn_init_scan->Disable();

  // next scan button
  m_btn_next_scan = new wxButton(this, wxID_ANY, _("Next Scan"));
  m_btn_next_scan->SetToolTip(_("Eliminate items from the current scan results that do not match "
                                "the current Search settings."));
  m_btn_next_scan->Bind(wxEVT_BUTTON, &CheatSearchTab::OnNextScanClicked, this);
  m_btn_next_scan->Disable();

  m_label_scan_disabled = new wxStaticText(this, wxID_ANY, _("No game is running."));

  // create AR code button
  m_btn_create_code = new wxButton(this, wxID_ANY, _("Create AR Code"));
  m_btn_create_code->Bind(wxEVT_BUTTON, &CheatSearchTab::OnCreateARCodeClicked, this);
  m_btn_create_code->Disable();

  // data sizes radiobox
  std::array<wxString, 3> data_size_names = {{_("8-bit"), _("16-bit"), _("32-bit")}};
  m_data_sizes = new wxRadioBox(this, wxID_ANY, _("Data Size"), wxDefaultPosition, wxDefaultSize,
                                static_cast<int>(data_size_names.size()), data_size_names.data());

  // ListView for search results
  m_lview_search_results = new wxListView(this, wxID_ANY, wxDefaultPosition, wxDefaultSize,
                                          wxLC_REPORT | wxLC_SINGLE_SEL);
  m_lview_search_results->AppendColumn(_("Address"));
  m_lview_search_results->AppendColumn(_("Value"));
  m_lview_search_results->AppendColumn(_("Value (float)"));
  m_lview_search_results->AppendColumn(_("Value (double)"));
  m_lview_search_results->Bind(wxEVT_LIST_ITEM_ACTIVATED, &CheatSearchTab::OnListViewItemActivated,
                               this);
  m_lview_search_results->Bind(wxEVT_LIST_ITEM_SELECTED, &CheatSearchTab::OnListViewItemSelected,
                               this);
  m_lview_search_results->Bind(wxEVT_LIST_ITEM_DESELECTED, &CheatSearchTab::OnListViewItemSelected,
                               this);

  // Result count
  m_label_results_count = new wxStaticText(this, wxID_ANY, _("Count:"));

  const int space5 = FromDIP(5);

  // results groupbox
  wxStaticBoxSizer* const sizer_cheat_search_results =
      new wxStaticBoxSizer(wxVERTICAL, this, _("Results"));
  sizer_cheat_search_results->AddSpacer(space5);
  sizer_cheat_search_results->Add(m_label_results_count, 0, wxLEFT | wxRIGHT, space5);
  sizer_cheat_search_results->AddSpacer(space5);
  sizer_cheat_search_results->Add(m_lview_search_results, 1, wxEXPAND | wxLEFT | wxRIGHT, space5);
  sizer_cheat_search_results->AddSpacer(space5);
  sizer_cheat_search_results->Add(m_btn_create_code, 0, wxEXPAND | wxLEFT | wxRIGHT, space5);
  sizer_cheat_search_results->AddSpacer(space5);

  // search value textbox
  m_textctrl_value_x = new wxTextCtrl(this, wxID_ANY, "0x0");
  m_textctrl_value_x->SetMinSize(WxUtils::GetTextWidgetMinSize(m_textctrl_value_x, "0x00000000  "));
  m_textctrl_value_x->SetToolTip(
      _("Value to match against. Can be Hex (\"0x\"), Octal (\"0\") or Decimal. "
        "Leave blank to filter each result against its own previous value."));

  // Filter types in the compare dropdown
  // TODO: Implement between search
  wxArrayString filters;
  filters.Add(_("Unknown"));
  filters.Add(_("Not Equal"));
  filters.Add(_("Equal"));
  filters.Add(_("Greater Than"));
  filters.Add(_("Less Than"));

  m_search_type = new wxChoice(this, wxID_ANY, wxDefaultPosition, wxDefaultSize, filters);
  m_search_type->Select(0);

  wxStaticBoxSizer* const sizer_cheat_search_filter =
      new wxStaticBoxSizer(wxVERTICAL, this, _("Search (clear to use previous value)"));
  sizer_cheat_search_filter->AddSpacer(space5);
  sizer_cheat_search_filter->Add(m_textctrl_value_x, 0, wxEXPAND | wxLEFT | wxRIGHT, space5);
  sizer_cheat_search_filter->AddSpacer(space5);
  sizer_cheat_search_filter->Add(m_search_type, 0, wxLEFT | wxRIGHT, space5);
  sizer_cheat_search_filter->AddSpacer(space5);

  // button sizer
  wxBoxSizer* boxButtons = new wxBoxSizer(wxHORIZONTAL);
  boxButtons->Add(m_btn_init_scan, 1);
  boxButtons->Add(m_btn_next_scan, 1, wxLEFT, space5);

  // right sizer
  wxBoxSizer* const sizer_right = new wxBoxSizer(wxVERTICAL);
  sizer_right->Add(m_data_sizes, 0, wxEXPAND);
  sizer_right->Add(sizer_cheat_search_filter, 0, wxEXPAND | wxTOP, space5);
  sizer_right->AddStretchSpacer(1);
  sizer_right->Add(m_label_scan_disabled, 0, wxALIGN_CENTER_HORIZONTAL | wxTOP, space5);
  sizer_right->Add(boxButtons, 0, wxEXPAND | wxTOP, space5);

  // main sizer
  wxBoxSizer* const sizer_main = new wxBoxSizer(wxHORIZONTAL);
  sizer_main->AddSpacer(space5);
  sizer_main->Add(sizer_cheat_search_results, 1, wxEXPAND | wxTOP | wxBOTTOM, space5);
  sizer_main->AddSpacer(space5);
  sizer_main->Add(sizer_right, 0, wxEXPAND | wxTOP | wxBOTTOM, space5);
  sizer_main->AddSpacer(space5);

  SetSizerAndFit(sizer_main);
}

void CheatSearchTab::UpdateGUI()
{
  bool core_running = Core::IsRunning();
  m_btn_init_scan->Enable(core_running);
  m_btn_next_scan->Enable(core_running && m_scan_is_initialized);
  m_label_scan_disabled->Show(!core_running);

  Layout();  // Label shown/hidden may require layout adjustment
}

void CheatSearchTab::OnNewScanClicked(wxCommandEvent& WXUNUSED(event))
{
  if (!Core::IsRunningAndStarted())
  {
    WxUtils::ShowErrorDialog(_("A game is not currently running."));
    return;
  }

  // Determine the user-selected data size for this search.
  m_search_type_size = (1 << m_data_sizes->GetSelection());

  // Set up the search results efficiently to prevent automatic re-allocations.
  m_search_results.clear();
  m_search_results.reserve(Memory::RAM_SIZE / m_search_type_size);

  // Enable the "Next Scan" button.
  m_scan_is_initialized = true;
  m_btn_next_scan->Enable();

  CheatSearchResult r;
  // can I assume cheatable values will be aligned like this?
  for (u32 addr = 0; addr != Memory::RAM_SIZE; addr += m_search_type_size)
  {
    r.address = addr;
    memcpy(&r.old_value, &Memory::m_pRAM[addr], m_search_type_size);
    m_search_results.push_back(r);
  }

  UpdateCheatSearchResultsList();
}

void CheatSearchTab::OnNextScanClicked(wxCommandEvent&)
{
  if (!Core::IsRunningAndStarted())
  {
    WxUtils::ShowErrorDialog(_("A game is not currently running."));
    return;
  }

  u32 user_x_val = 0;
  bool blank_user_value = m_textctrl_value_x->IsEmpty();
  if (!blank_user_value)
  {
    if (!ParseUserEnteredValue(&user_x_val))
      return;
  }

  FilterCheatSearchResults(user_x_val, blank_user_value);

  UpdateCheatSearchResultsList();
}

void CheatSearchTab::OnCreateARCodeClicked(wxCommandEvent&)
{
  long idx = m_lview_search_results->GetNextItem(-1, wxLIST_NEXT_ALL, wxLIST_STATE_SELECTED);
  if (idx == wxNOT_FOUND)
    return;

  const u32 address = m_search_results[idx].address | ((m_search_type_size & ~1) << 24);

  CreateCodeDialog arcode_dlg(this, address);
  arcode_dlg.ShowModal();
}

void CheatSearchTab::OnListViewItemActivated(wxListEvent&)
{
  if (!m_btn_create_code->IsEnabled())
    return;

  wxCommandEvent fake(wxEVT_BUTTON, m_btn_create_code->GetId());
  m_btn_create_code->GetEventHandler()->ProcessEvent(fake);
}

void CheatSearchTab::OnListViewItemSelected(wxListEvent&)
{
  // Toggle "Create AR Code" Button
  m_btn_create_code->Enable(m_lview_search_results->GetSelectedItemCount() > 0);
}

void CheatSearchTab::OnTimerUpdate(wxTimerEvent&)
{
  if (Core::GetState() != Core::CORE_RUN)
    return;

  // Only update the currently visible list rows.
  long first = m_lview_search_results->GetTopItem();
  long last = std::min<long>(m_lview_search_results->GetItemCount(),
                             first + m_lview_search_results->GetCountPerPage());

  m_lview_search_results->Freeze();

  while (first < last)
  {
    UpdateCheatSearchResultItem(first);
    first++;
  }

  m_lview_search_results->Thaw();
}

void CheatSearchTab::UpdateCheatSearchResultsList()
{
  m_update_timer.Stop();
  m_lview_search_results->DeleteAllItems();
  m_btn_create_code->Disable();

  wxString count_label = wxString::Format(_("Count: %lu"), (unsigned long)m_search_results.size());
  if (m_search_results.size() > MAX_CHEAT_SEARCH_RESULTS_DISPLAY)
  {
    count_label += _(" (too many to display)");
  }
  else
  {
    m_lview_search_results->Freeze();

    for (size_t i = 0; i < m_search_results.size(); i++)
    {
      // Insert into the list control.
      wxString address_string = wxString::Format("0x%08X", m_search_results[i].address);
      long index = m_lview_search_results->InsertItem(static_cast<long>(i), address_string);

      UpdateCheatSearchResultItem(index);
    }

    m_lview_search_results->Thaw();

    // Half-second update interval
    m_update_timer.Start(500);
  }

  m_label_results_count->SetLabel(count_label);
}

void CheatSearchTab::UpdateCheatSearchResultItem(long index)
{
  u32 address_value = 0;
  std::memcpy(&address_value, &Memory::m_pRAM[m_search_results[index].address], m_search_type_size);

  u32 display_value = SwapValue(address_value);

  wxString buf;
  buf.Printf("0x%08X", display_value);
  m_lview_search_results->SetItem(index, 1, buf);

  float display_value_float = 0.0f;
  std::memcpy(&display_value_float, &display_value, sizeof(u32));
  buf.Printf("%e", display_value_float);
  m_lview_search_results->SetItem(index, 2, buf);

  double display_value_double = 0.0;
  std::memcpy(&display_value_double, &display_value, sizeof(u32));
  buf.Printf("%e", display_value_double);
  m_lview_search_results->SetItem(index, 3, buf);
}

enum class ComparisonMask
{
  EQUAL = 0x1,
  GREATER_THAN = 0x2,
  LESS_THAN = 0x4
};

static ComparisonMask operator|(ComparisonMask comp1, ComparisonMask comp2)
{
  return static_cast<ComparisonMask>(static_cast<int>(comp1) | static_cast<int>(comp2));
}

static ComparisonMask operator&(ComparisonMask comp1, ComparisonMask comp2)
{
  return static_cast<ComparisonMask>(static_cast<int>(comp1) & static_cast<int>(comp2));
}

void CheatSearchTab::FilterCheatSearchResults(u32 value, bool prev)
{
  static const std::array<ComparisonMask, 5> filters{
      {ComparisonMask::EQUAL | ComparisonMask::GREATER_THAN | ComparisonMask::LESS_THAN,  // Unknown
       ComparisonMask::GREATER_THAN | ComparisonMask::LESS_THAN,  // Not Equal
       ComparisonMask::EQUAL, ComparisonMask::GREATER_THAN, ComparisonMask::LESS_THAN}};
  ComparisonMask filter_mask = filters[m_search_type->GetSelection()];

  std::vector<CheatSearchResult> filtered_results;
  filtered_results.reserve(m_search_results.size());

  for (CheatSearchResult& result : m_search_results)
  {
    if (prev)
      value = result.old_value;

    // with big endian, can just use memcmp for ><= comparison
    int cmp_result = std::memcmp(&Memory::m_pRAM[result.address], &value, m_search_type_size);
    ComparisonMask cmp_mask;
    if (cmp_result < 0)
      cmp_mask = ComparisonMask::LESS_THAN;
    else if (cmp_result)
      cmp_mask = ComparisonMask::GREATER_THAN;
    else
      cmp_mask = ComparisonMask::EQUAL;

    if (static_cast<int>(cmp_mask & filter_mask))
    {
      std::memcpy(&result.old_value, &Memory::m_pRAM[result.address], m_search_type_size);
      filtered_results.push_back(result);
    }
  }

  m_search_results.swap(filtered_results);
}

bool CheatSearchTab::ParseUserEnteredValue(u32* out) const
{
  unsigned long parsed_x_val = 0;
  wxString x_val = m_textctrl_value_x->GetValue();

  if (!x_val.ToULong(&parsed_x_val, 0))
  {
    WxUtils::ShowErrorDialog(_("You must enter a valid decimal, hexadecimal or octal value."));
    return false;
  }

  *out = SwapValue(static_cast<u32>(parsed_x_val));
  return true;
}

u32 CheatSearchTab::SwapValue(u32 value) const
{
  switch (m_search_type_size)
  {
  case 2:
    *(u16*)&value = Common::swap16((u8*)&value);
    break;
  case 4:
    value = Common::swap32(value);
    break;
  }

  return value;
}