/******************************************************************************
 * The MIT License (MIT)
 *
 * Copyright (c) 2017 Baldur Karlsson
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 ******************************************************************************/

#include "PythonShell.h"
#include <QFontDatabase>
#include <QKeyEvent>
#include <QScrollBar>
#include "3rdparty/scintilla/include/SciLexer.h"
#include "3rdparty/scintilla/include/qt/ScintillaEdit.h"
#include "Code/ScintillaSyntax.h"
#include "Code/pyrenderdoc/PythonContext.h"
#include "ui_PythonShell.h"

PythonShell::PythonShell(ICaptureContext &ctx, QWidget *parent)
    : QFrame(parent), ui(new Ui::PythonShell), m_Ctx(ctx)
{
  ui->setupUi(this);

  QObject::connect(ui->lineInput, &RDLineEdit::keyPress, this, &PythonShell::interactive_keypress);

  ui->lineInput->setFont(QFontDatabase::systemFont(QFontDatabase::FixedFont));
  ui->interactiveOutput->setFont(QFontDatabase::systemFont(QFontDatabase::FixedFont));
  ui->scriptOutput->setFont(QFontDatabase::systemFont(QFontDatabase::FixedFont));

  scriptEditor = new ScintillaEdit(this);

  scriptEditor->setMarginLeft(4);
  scriptEditor->setMarginWidthN(0, 32);
  scriptEditor->setMarginWidthN(1, 0);
  scriptEditor->setMarginWidthN(2, 16);
  scriptEditor->setObjectName("scriptEditor");

  scriptEditor->markerSetBack(CURRENT_MARKER, SCINTILLA_COLOUR(240, 128, 128));
  scriptEditor->markerSetBack(CURRENT_MARKER + 1, SCINTILLA_COLOUR(240, 128, 128));
  scriptEditor->markerDefine(CURRENT_MARKER, SC_MARK_SHORTARROW);
  scriptEditor->markerDefine(CURRENT_MARKER + 1, SC_MARK_BACKGROUND);

  ConfigureSyntax(scriptEditor, SCLEX_PYTHON);

  scriptEditor->setTabWidth(4);

  scriptEditor->setScrollWidth(1);
  scriptEditor->setScrollWidthTracking(true);

  scriptEditor->colourise(0, -1);

  QObject::connect(scriptEditor, &ScintillaEdit::modified, [this](int type, int, int, int,
                                                                  const QByteArray &, int, int, int) {
    if(type & (SC_MOD_INSERTTEXT | SC_MOD_DELETETEXT | SC_MOD_BEFOREINSERT | SC_MOD_BEFOREDELETE))
    {
      scriptEditor->markerDeleteAll(CURRENT_MARKER);
      scriptEditor->markerDeleteAll(CURRENT_MARKER + 1);
    }
  });

  ui->scriptSplitter->insertWidget(0, scriptEditor);
  int w = ui->scriptSplitter->rect().width();
  ui->scriptSplitter->setSizes({w * 2 / 3, w / 3});

  ui->tabWidget->setCurrentIndex(0);

  interactiveContext = NULL;

  enableButtons(true);

  // reset output to default
  on_clear_clicked();
  on_newScript_clicked();
}

PythonShell::~PythonShell()
{
  m_Ctx.BuiltinWindowClosed(this);

  interactiveContext->Finish();

  delete ui;
}

void PythonShell::on_execute_clicked()
{
  QString command = ui->lineInput->text();

  appendText(ui->interactiveOutput, command + "\n");

  if(command.trimmed().length() > 0)
    interactiveContext->executeString(command, true);

  history.push_front(command);
  historyidx = -1;

  ui->lineInput->clear();

  appendText(ui->interactiveOutput, ">> ");
}

void PythonShell::on_clear_clicked()
{
  QString minidocHeader = scriptHeader();

  minidocHeader += "\n\n>> ";

  ui->interactiveOutput->setText(minidocHeader);

  if(interactiveContext)
    interactiveContext->Finish();

  interactiveContext = newContext();
}

void PythonShell::on_newScript_clicked()
{
  QString minidocHeader = scriptHeader();

  minidocHeader.replace('\n', "\n# ");

  minidocHeader = "# " + minidocHeader + "\n\n";

  scriptEditor->setText(minidocHeader.toUtf8().data());

  scriptEditor->emptyUndoBuffer();
}

void PythonShell::on_openScript_clicked()
{
  QString filename =
      RDDialog::getOpenFileName(this, "Open Python Script", "", tr("Python scripts (*.py)"));

  if(filename != "")
  {
    QFile f(filename);
    if(f.open(QIODevice::ReadOnly | QIODevice::Text))
    {
      scriptEditor->setText(f.readAll().data());
    }
    else
    {
      RDDialog::critical(this, "Error loading script", tr("Couldn't open path %1.").arg(filename));
    }
  }
}

void PythonShell::on_saveScript_clicked()
{
  QString filename = RDDialog::getSaveFileName(this, tr("Save Python Script"), QString(),
                                               tr("Python scripts (*.py)"));

  if(filename != "")
  {
    QDir dirinfo = QFileInfo(filename).dir();
    if(dirinfo.exists())
    {
      QFile f(filename);
      if(f.open(QIODevice::WriteOnly | QIODevice::Truncate))
      {
        f.write(scriptEditor->getText(scriptEditor->textLength() + 1));
      }
      else
      {
        RDDialog::critical(
            this, tr("Error saving script"),
            tr("Couldn't open path %1 for write.\n%2").arg(filename).arg(f.errorString()));
      }
    }
    else
    {
      RDDialog::critical(this, tr("Invalid directory"),
                         tr("Cannot find target directory to save to"));
    }
  }
}

void PythonShell::on_runScript_clicked()
{
  PythonContext *context = newContext();

  ui->scriptOutput->clear();

  QString script = QString::fromUtf8(scriptEditor->getText(scriptEditor->textLength() + 1));

  enableButtons(false);

  LambdaThread *thread = new LambdaThread([this, script, context]() {

    scriptContext = context;
    context->executeString("script.py", script);
    scriptContext = NULL;

    context->Finish();

    GUIInvoke::call([this]() { enableButtons(true); });
  });

  thread->selfDelete(true);
  thread->start();
}

void PythonShell::on_abortRun_clicked()
{
  if(scriptContext)
    scriptContext->abort();
}

void PythonShell::traceLine(const QString &file, int line)
{
  if(QObject::sender() == (QObject *)interactiveContext)
    return;

  scriptEditor->markerDeleteAll(CURRENT_MARKER);
  scriptEditor->markerDeleteAll(CURRENT_MARKER + 1);

  scriptEditor->markerAdd(line > 0 ? line - 1 : 0, CURRENT_MARKER);
  scriptEditor->markerAdd(line > 0 ? line - 1 : 0, CURRENT_MARKER + 1);
}

void PythonShell::exception(const QString &type, const QString &value, QList<QString> frames)
{
  QTextEdit *out = ui->scriptOutput;
  if(QObject::sender() == (QObject *)interactiveContext)
    out = ui->interactiveOutput;

  QString exString;

  if(!out->toPlainText().endsWith('\n'))
    exString = "\n";
  if(!frames.isEmpty())
  {
    exString += "Traceback (most recent call last):\n";
    for(const QString &f : frames)
      exString += QString("  %1\n").arg(f);
  }
  exString += QString("%1: %2\n").arg(type).arg(value);

  appendText(out, exString);
}

void PythonShell::textOutput(bool isStdError, const QString &output)
{
  QTextEdit *out = ui->scriptOutput;
  if(QObject::sender() == (QObject *)interactiveContext)
    out = ui->interactiveOutput;

  appendText(out, output);
}

void PythonShell::interactive_keypress(QKeyEvent *event)
{
  if(event->key() == Qt::Key_Return || event->key() == Qt::Key_Enter)
    on_execute_clicked();

  bool moved = false;

  if(event->key() == Qt::Key_Down && historyidx > -1)
  {
    historyidx--;

    moved = true;
  }

  QString workingtext = "";

  if(event->key() == Qt::Key_Up && historyidx + 1 < history.count())
  {
    if(historyidx == -1)
      workingtext = ui->lineInput->text();

    historyidx++;

    moved = true;
  }

  if(moved)
  {
    if(historyidx == -1)
      ui->lineInput->setText(workingtext);
    else
      ui->lineInput->setText(history[historyidx]);

    ui->lineInput->deselect();
  }
}

QString PythonShell::scriptHeader()
{
  return tr(R"(RenderDoc Python console, powered by python %1.
The 'pyrenderdoc' object is the current CaptureContext instance.
The 'renderdoc' and 'qrenderdoc' modules are available.
Documentation is available: https://renderdoc.org/docs/python_api/index.html)")
      .arg(interactiveContext->versionString());
}

void PythonShell::appendText(QTextEdit *output, const QString &text)
{
  output->moveCursor(QTextCursor::End);
  output->insertPlainText(text);

  // scroll to the bottom
  QScrollBar *vscroll = output->verticalScrollBar();
  vscroll->setValue(vscroll->maximum());
}

void PythonShell::enableButtons(bool enable)
{
  ui->newScript->setEnabled(enable);
  ui->openScript->setEnabled(enable);
  ui->saveScript->setEnabled(enable);
  ui->runScript->setEnabled(enable);
  ui->abortRun->setEnabled(!enable);
}

PythonContext *PythonShell::newContext()
{
  PythonContext *ret = new PythonContext();

  QObject::connect(ret, &PythonContext::traceLine, this, &PythonShell::traceLine);
  QObject::connect(ret, &PythonContext::exception, this, &PythonShell::exception);
  QObject::connect(ret, &PythonContext::textOutput, this, &PythonShell::textOutput);

  ret->setGlobal("pyrenderdoc", &m_Ctx);

  return ret;
}