// Copyright 2018 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include "DolphinQt/FIFO/FIFOAnalyzer.h"

#include <QGroupBox>
#include <QHBoxLayout>
#include <QHeaderView>
#include <QLabel>
#include <QLineEdit>
#include <QListWidget>
#include <QPushButton>
#include <QSplitter>
#include <QTextBrowser>
#include <QTreeWidget>
#include <QTreeWidgetItem>

#include "Common/Assert.h"
#include "Common/Swap.h"
#include "Core/FifoPlayer/FifoPlayer.h"

#include "DolphinQt/Settings.h"

#include "VideoCommon/BPMemory.h"
#include "VideoCommon/CPMemory.h"
#include "VideoCommon/OpcodeDecoding.h"
#include "VideoCommon/XFStructs.h"

constexpr int FRAME_ROLE = Qt::UserRole;
constexpr int OBJECT_ROLE = Qt::UserRole + 1;

FIFOAnalyzer::FIFOAnalyzer()
{
  CreateWidgets();
  ConnectWidgets();

  UpdateTree();

  auto& settings = Settings::GetQSettings();

  m_object_splitter->restoreState(
      settings.value(QStringLiteral("fifoanalyzer/objectsplitter")).toByteArray());
  m_search_splitter->restoreState(
      settings.value(QStringLiteral("fifoanalyzer/searchsplitter")).toByteArray());

  m_detail_list->setFont(Settings::Instance().GetDebugFont());
  m_entry_detail_browser->setFont(Settings::Instance().GetDebugFont());

  connect(&Settings::Instance(), &Settings::DebugFontChanged, this, [this] {
    m_detail_list->setFont(Settings::Instance().GetDebugFont());
    m_entry_detail_browser->setFont(Settings::Instance().GetDebugFont());
  });
}

FIFOAnalyzer::~FIFOAnalyzer()
{
  auto& settings = Settings::GetQSettings();

  settings.setValue(QStringLiteral("fifoanalyzer/objectsplitter"), m_object_splitter->saveState());
  settings.setValue(QStringLiteral("fifoanalyzer/searchsplitter"), m_search_splitter->saveState());
}

void FIFOAnalyzer::CreateWidgets()
{
  m_tree_widget = new QTreeWidget;
  m_detail_list = new QListWidget;
  m_entry_detail_browser = new QTextBrowser;

  m_object_splitter = new QSplitter(Qt::Horizontal);

  m_object_splitter->addWidget(m_tree_widget);
  m_object_splitter->addWidget(m_detail_list);

  m_tree_widget->header()->hide();

  m_search_box = new QGroupBox(tr("Search Current Object"));
  m_search_edit = new QLineEdit;
  m_search_new = new QPushButton(tr("Search"));
  m_search_next = new QPushButton(tr("Next Match"));
  m_search_previous = new QPushButton(tr("Previous Match"));
  m_search_label = new QLabel;

  m_search_next->setEnabled(false);
  m_search_previous->setEnabled(false);

  auto* box_layout = new QHBoxLayout;

  box_layout->addWidget(m_search_edit);
  box_layout->addWidget(m_search_new);
  box_layout->addWidget(m_search_next);
  box_layout->addWidget(m_search_previous);
  box_layout->addWidget(m_search_label);

  m_search_box->setLayout(box_layout);

  m_search_box->setMaximumHeight(m_search_box->minimumSizeHint().height());

  m_search_splitter = new QSplitter(Qt::Vertical);

  m_search_splitter->addWidget(m_object_splitter);
  m_search_splitter->addWidget(m_entry_detail_browser);
  m_search_splitter->addWidget(m_search_box);

  auto* layout = new QHBoxLayout;
  layout->addWidget(m_search_splitter);

  setLayout(layout);
}

void FIFOAnalyzer::ConnectWidgets()
{
  connect(m_tree_widget, &QTreeWidget::itemSelectionChanged, this, &FIFOAnalyzer::UpdateDetails);
  connect(m_detail_list, &QListWidget::itemSelectionChanged, this,
          &FIFOAnalyzer::UpdateDescription);

  connect(m_search_edit, &QLineEdit::returnPressed, this, &FIFOAnalyzer::BeginSearch);
  connect(m_search_new, &QPushButton::clicked, this, &FIFOAnalyzer::BeginSearch);
  connect(m_search_next, &QPushButton::clicked, this, &FIFOAnalyzer::FindNext);
  connect(m_search_previous, &QPushButton::clicked, this, &FIFOAnalyzer::FindPrevious);
}

void FIFOAnalyzer::Update()
{
  UpdateTree();
  UpdateDetails();
  UpdateDescription();
}

void FIFOAnalyzer::UpdateTree()
{
  m_tree_widget->clear();

  if (!FifoPlayer::GetInstance().IsPlaying())
  {
    m_tree_widget->addTopLevelItem(new QTreeWidgetItem({tr("No recording loaded.")}));
    return;
  }

  auto* recording_item = new QTreeWidgetItem({tr("Recording")});

  m_tree_widget->addTopLevelItem(recording_item);

  auto* file = FifoPlayer::GetInstance().GetFile();

  const u32 frame_count = file->GetFrameCount();
  for (u32 frame = 0; frame < frame_count; frame++)
  {
    auto* frame_item = new QTreeWidgetItem({tr("Frame %1").arg(frame)});

    recording_item->addChild(frame_item);

    const u32 object_count = FifoPlayer::GetInstance().GetFrameObjectCount(frame);
    for (u32 object = 0; object < object_count; object++)
    {
      auto* object_item = new QTreeWidgetItem({tr("Object %1").arg(object)});

      frame_item->addChild(object_item);

      object_item->setData(0, FRAME_ROLE, frame);
      object_item->setData(0, OBJECT_ROLE, object);
    }
  }
}

void FIFOAnalyzer::UpdateDetails()
{
  // Clearing the detail list can update the selection, which causes UpdateDescription to be called
  // immediately.  However, the object data offsets have not been recalculated yet, which can cause
  // the wrong data to be used, potentially leading to out of bounds data or other bad things.
  // Clear m_object_data_offsets first, so that UpdateDescription exits immediately.
  m_object_data_offsets.clear();
  m_detail_list->clear();
  m_search_results.clear();
  m_search_next->setEnabled(false);
  m_search_previous->setEnabled(false);
  m_search_label->clear();

  if (!FifoPlayer::GetInstance().IsPlaying())
    return;

  const auto items = m_tree_widget->selectedItems();

  if (items.isEmpty() || items[0]->data(0, OBJECT_ROLE).isNull())
    return;

  const u32 frame_nr = items[0]->data(0, FRAME_ROLE).toUInt();
  const u32 object_nr = items[0]->data(0, OBJECT_ROLE).toUInt();

  const auto& frame_info = FifoPlayer::GetInstance().GetAnalyzedFrameInfo(frame_nr);
  const auto& fifo_frame = FifoPlayer::GetInstance().GetFile()->GetFrame(frame_nr);

  // Note that frame_info.objectStarts[object_nr] is the start of the primitive data,
  // but we want to start with the register updates which happen before that.
  const u32 object_start = (object_nr == 0 ? 0 : frame_info.objectEnds[object_nr - 1]);
  const u32 object_nonprim_size = frame_info.objectStarts[object_nr] - object_start;
  const u32 object_size = frame_info.objectEnds[object_nr] - object_start;

  const u8* const object = &fifo_frame.fifoData[object_start];

  u32 object_offset = 0;
  while (object_offset < object_nonprim_size)
  {
    QString new_label;
    const u32 start_offset = object_offset;
    m_object_data_offsets.push_back(start_offset);

    const u8 command = object[object_offset++];
    switch (command)
    {
    case OpcodeDecoder::GX_NOP:
      new_label = QStringLiteral("NOP");
      break;

    case OpcodeDecoder::GX_CMD_UNKNOWN_METRICS:
      new_label = QStringLiteral("GX_CMD_UNKNOWN_METRICS");
      break;

    case OpcodeDecoder::GX_CMD_INVL_VC:
      new_label = QStringLiteral("GX_CMD_INVL_VC");
      break;

    case OpcodeDecoder::GX_LOAD_CP_REG:
    {
      const u8 cmd2 = object[object_offset++];
      const u32 value = Common::swap32(&object[object_offset]);
      object_offset += 4;

      const auto [name, desc] = GetCPRegInfo(cmd2, value);
      ASSERT(!name.empty());

      new_label = QStringLiteral("CP  %1  %2  %3")
                      .arg(cmd2, 2, 16, QLatin1Char('0'))
                      .arg(value, 8, 16, QLatin1Char('0'))
                      .arg(QString::fromStdString(name));
    }
    break;

    case OpcodeDecoder::GX_LOAD_XF_REG:
    {
      const auto [name, desc] = GetXFTransferInfo(&object[object_offset]);
      const u32 cmd2 = Common::swap32(&object[object_offset]);
      object_offset += 4;
      ASSERT(!name.empty());

      const u8 stream_size = ((cmd2 >> 16) & 15) + 1;

      new_label = QStringLiteral("XF  %1  ").arg(cmd2, 8, 16, QLatin1Char('0'));

      for (u8 i = 0; i < stream_size; i++)
      {
        const u32 value = Common::swap32(&object[object_offset]);
        object_offset += 4;

        new_label += QStringLiteral("%1 ").arg(value, 8, 16, QLatin1Char('0'));
      }

      new_label += QStringLiteral("  ") + QString::fromStdString(name);
    }
    break;

    case OpcodeDecoder::GX_LOAD_INDX_A:
      new_label = QStringLiteral("LOAD INDX A");
      object_offset += 4;
      break;
    case OpcodeDecoder::GX_LOAD_INDX_B:
      new_label = QStringLiteral("LOAD INDX B");
      object_offset += 4;
      break;
    case OpcodeDecoder::GX_LOAD_INDX_C:
      new_label = QStringLiteral("LOAD INDX C");
      object_offset += 4;
      break;
    case OpcodeDecoder::GX_LOAD_INDX_D:
      new_label = QStringLiteral("LOAD INDX D");
      object_offset += 4;
      break;

    case OpcodeDecoder::GX_CMD_CALL_DL:
      // The recorder should have expanded display lists into the fifo stream and skipped the
      // call to start them
      // That is done to make it easier to track where memory is updated
      ASSERT(false);
      object_offset += 8;
      new_label = QStringLiteral("CALL DL");
      break;

    case OpcodeDecoder::GX_LOAD_BP_REG:
    {
      const u8 cmd2 = object[object_offset++];
      const u32 cmddata = Common::swap24(&object[object_offset]);
      object_offset += 3;

      const auto [name, desc] = GetBPRegInfo(cmd2, cmddata);
      ASSERT(!name.empty());

      new_label = QStringLiteral("BP  %1  %2  %3")
                      .arg(cmd2, 2, 16, QLatin1Char('0'))
                      .arg(cmddata, 6, 16, QLatin1Char('0'))
                      .arg(QString::fromStdString(name));
    }
    break;

    default:
      new_label = tr("Unexpected 0x80 call? Aborting...");
      object_offset = object_nonprim_size;
      break;
    }
    new_label = QStringLiteral("%1:  ").arg(object_start + start_offset, 8, 16, QLatin1Char('0')) +
                new_label;
    m_detail_list->addItem(new_label);
  }

  // Object primitive data
  ASSERT(object_offset == object_nonprim_size);
  m_object_data_offsets.push_back(object_offset);

  const u8 cmd = object[object_offset++];
  const u16 vertex_count = Common::swap16(&object[object_offset]);
  object_offset += 2;

  const u32 object_prim_size = object_size - object_offset;

  QString new_label = QStringLiteral("%1:  %2 %3  ")
                          .arg(object_start + object_offset, 8, 16, QLatin1Char('0'))
                          .arg(cmd, 2, 16, QLatin1Char('0'))
                          .arg(vertex_count, 4, 16, QLatin1Char('0'));

  while (object_offset < object_size)
  {
    u32 byte = object[object_offset++];
    new_label += QStringLiteral("%1").arg(byte, 2, 16, QLatin1Char('0'));
  }

  if (vertex_count != 0 && (object_prim_size % vertex_count) != 0)
  {
    new_label += QLatin1Char{'\n'};
    new_label += tr("NOTE: Stream size doesn't match actual data length");
  }

  m_detail_list->addItem(new_label);

  // Needed to ensure the description updates when changing objects
  m_detail_list->setCurrentRow(0);
}

void FIFOAnalyzer::BeginSearch()
{
  const QString search_str = m_search_edit->text();

  if (!FifoPlayer::GetInstance().IsPlaying())
    return;

  const auto items = m_tree_widget->selectedItems();

  if (items.isEmpty() || items[0]->data(0, FRAME_ROLE).isNull() ||
      items[0]->data(0, OBJECT_ROLE).isNull())
  {
    m_search_label->setText(tr("Invalid search parameters (no object selected)"));
    return;
  }

  // TODO: Remove even string length limit
  if (search_str.length() % 2)
  {
    m_search_label->setText(tr("Invalid search string (only even string lengths supported)"));
    return;
  }

  const size_t length = search_str.length() / 2;

  std::vector<u8> search_val;

  for (size_t i = 0; i < length; i++)
  {
    const QString byte_str = search_str.mid(static_cast<int>(i * 2), 2);

    bool good;
    u8 value = byte_str.toUInt(&good, 16);

    if (!good)
    {
      m_search_label->setText(tr("Invalid search string (couldn't convert to number)"));
      return;
    }

    search_val.push_back(value);
  }

  m_search_results.clear();

  const u32 frame_nr = items[0]->data(0, FRAME_ROLE).toUInt();
  const u32 object_nr = items[0]->data(0, OBJECT_ROLE).toUInt();

  const AnalyzedFrameInfo& frame_info = FifoPlayer::GetInstance().GetAnalyzedFrameInfo(frame_nr);
  const FifoFrameInfo& fifo_frame = FifoPlayer::GetInstance().GetFile()->GetFrame(frame_nr);

  const u32 object_start = (object_nr == 0 ? 0 : frame_info.objectEnds[object_nr - 1]);
  const u32 object_size = frame_info.objectEnds[object_nr] - object_start;

  const u8* const object = &fifo_frame.fifoData[object_start];

  // TODO: Support searching for bit patterns
  for (u32 cmd_nr = 0; cmd_nr < m_object_data_offsets.size(); cmd_nr++)
  {
    const u32 cmd_start = m_object_data_offsets[cmd_nr];
    const u32 cmd_end = (cmd_nr + 1 == m_object_data_offsets.size()) ?
                            object_size :
                            m_object_data_offsets[cmd_nr + 1];

    const u8* const cmd_start_ptr = &object[cmd_start];
    const u8* const cmd_end_ptr = &object[cmd_end];

    for (const u8* ptr = cmd_start_ptr; ptr < cmd_end_ptr - length + 1; ptr++)
    {
      if (std::equal(search_val.begin(), search_val.end(), ptr))
      {
        m_search_results.emplace_back(frame_nr, object_nr, cmd_nr);
        break;
      }
    }
  }

  ShowSearchResult(0);

  m_search_label->setText(
      tr("Found %1 results for \"%2\"").arg(m_search_results.size()).arg(search_str));
}

void FIFOAnalyzer::FindNext()
{
  const int index = m_detail_list->currentRow();
  ASSERT(index >= 0);

  auto next_result =
      std::find_if(m_search_results.begin(), m_search_results.end(),
                   [index](auto& result) { return result.m_cmd > static_cast<u32>(index); });
  if (next_result != m_search_results.end())
  {
    ShowSearchResult(next_result - m_search_results.begin());
  }
}

void FIFOAnalyzer::FindPrevious()
{
  const int index = m_detail_list->currentRow();
  ASSERT(index >= 0);

  auto prev_result =
      std::find_if(m_search_results.rbegin(), m_search_results.rend(),
                   [index](auto& result) { return result.m_cmd < static_cast<u32>(index); });
  if (prev_result != m_search_results.rend())
  {
    ShowSearchResult((m_search_results.rend() - prev_result) - 1);
  }
}

void FIFOAnalyzer::ShowSearchResult(size_t index)
{
  if (m_search_results.empty())
    return;

  if (index >= m_search_results.size())
  {
    ShowSearchResult(m_search_results.size() - 1);
    return;
  }

  const auto& result = m_search_results[index];

  QTreeWidgetItem* object_item =
      m_tree_widget->topLevelItem(0)->child(result.m_frame)->child(result.m_object);

  m_tree_widget->setCurrentItem(object_item);
  m_detail_list->setCurrentRow(result.m_cmd);

  m_search_next->setEnabled(index + 1 < m_search_results.size());
  m_search_previous->setEnabled(index > 0);
}

void FIFOAnalyzer::UpdateDescription()
{
  m_entry_detail_browser->clear();

  if (!FifoPlayer::GetInstance().IsPlaying())
    return;

  const auto items = m_tree_widget->selectedItems();

  if (items.isEmpty() || m_object_data_offsets.empty())
    return;

  if (items[0]->data(0, FRAME_ROLE).isNull() || items[0]->data(0, OBJECT_ROLE).isNull())
    return;

  const u32 frame_nr = items[0]->data(0, FRAME_ROLE).toUInt();
  const u32 object_nr = items[0]->data(0, OBJECT_ROLE).toUInt();
  const u32 entry_nr = m_detail_list->currentRow();

  const AnalyzedFrameInfo& frame_info = FifoPlayer::GetInstance().GetAnalyzedFrameInfo(frame_nr);
  const FifoFrameInfo& fifo_frame = FifoPlayer::GetInstance().GetFile()->GetFrame(frame_nr);

  const u32 object_start = (object_nr == 0 ? 0 : frame_info.objectEnds[object_nr - 1]);
  const u8* cmddata = &fifo_frame.fifoData[object_start + m_object_data_offsets[entry_nr]];

  // TODO: Not sure whether we should bother translating the descriptions

  QString text;
  if (*cmddata == OpcodeDecoder::GX_LOAD_BP_REG)
  {
    const u8 cmd = *(cmddata + 1);
    const u32 value = Common::swap24(cmddata + 2);

    const auto [name, desc] = GetBPRegInfo(cmd, value);
    ASSERT(!name.empty());

    text = tr("BP register ");
    text += QString::fromStdString(name);
    text += QLatin1Char{'\n'};

    if (desc.empty())
      text += tr("No description available");
    else
      text += QString::fromStdString(desc);
  }
  else if (*cmddata == OpcodeDecoder::GX_LOAD_CP_REG)
  {
    const u8 cmd = *(cmddata + 1);
    const u32 value = Common::swap32(cmddata + 2);

    const auto [name, desc] = GetCPRegInfo(cmd, value);
    ASSERT(!name.empty());

    text = tr("CP register ");
    text += QString::fromStdString(name);
    text += QLatin1Char{'\n'};

    if (desc.empty())
      text += tr("No description available");
    else
      text += QString::fromStdString(desc);
  }
  else if (*cmddata == OpcodeDecoder::GX_LOAD_XF_REG)
  {
    const auto [name, desc] = GetXFTransferInfo(cmddata + 1);
    ASSERT(!name.empty());

    text = tr("XF register ");
    text += QString::fromStdString(name);
    text += QLatin1Char{'\n'};

    if (desc.empty())
      text += tr("No description available");
    else
      text += QString::fromStdString(desc);
  }
  else
  {
    text = tr("No description available");
  }

  m_entry_detail_browser->setText(text);
}