/****************************************************************************

   Copyright (C) 2002-2008 Gilles Debunne. All rights reserved.

   This file is part of the QGLViewer library version 2.3.5.

   http://www.libqglviewer.com - contact@libqglviewer.com

   This file may be used under the terms of the GNU General Public License
   versions 2.0 or 3.0 as published by the Free Software Foundation and
   appearing in the LICENSE file included in the packaging of this file.
   In addition, as a special exception, Gilles Debunne gives you certain
   additional rights, described in the file GPL_EXCEPTION in this package.

   libQGLViewer uses dual licensing. Commercial/proprietary software must
   purchase a libQGLViewer Commercial License.

   This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
   WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

 *****************************************************************************/

#include "agoraViewer.h"
#include "board.h"

#include <fstream>
#include <qmessagebox.h>
#include <qfileinfo.h>
#include <qfiledialog.h>
#include <qstatusbar.h>
#include <qtextedit.h>
#include <qtimer.h>

#if QT_VERSION >= 0x040000
#  include "ui_agoraWindow.Qt4.h"
class AgoraWindow : public QMainWindow, public Ui::AgoraWindow {
};
#else
#  include <qmainwindow.h>
#endif

using namespace std;
using namespace qglviewer;

static QString colorString[2] = { "White", "Black" };

class BoardConstraint : public Constraint {
public:
  virtual void constrainRotation(Quaternion& q, Frame* const fr)
  {
    const Vec up = fr->transformOf(Vec(0.0, 0.0, 1.0));
    Vec axis = q.axis();
    float angle = 2.0 * acos(q[3]);
    if(fabs(axis * up) > fabs(axis.x))
      axis.projectOnAxis(up);
    else {
      angle = (axis.x > 0.0) ? angle : -angle;
      axis.setValue(fabs(axis.x), 0.0, 0.0);
      const float currentAngle = asin(fr->inverseTransformOf(Vec(0.0, 0.0, -1.0)).z);
      if(currentAngle + angle > -0.2)
        angle = -0.2 - currentAngle;         // Not too low
      if(currentAngle + angle < -M_PI / 2.0)
        angle = -M_PI / 2.0 - currentAngle;         // Do not pass on the other side
    }
    q = Quaternion(axis, angle);
  }
};

#if QT_VERSION < 0x040000
AgoraViewer::AgoraViewer(QWidget* parent, const char* name)
  : QGLViewer(parent, name)
  ,
#else
AgoraViewer::AgoraViewer(QWidget* parent)
  : QGLViewer(parent)
  ,
#endif
  boardFileName_("standard.ago")
  , selectedPiece_(-1)
  , displayPossibleMoves_(true)
  , animatePlays_(false /*true*/)
  , animationStep_(0)
{
  kfi_ = new KeyFrameInterpolator(new Frame());

  QObject::connect(kfi_, SIGNAL(interpolated()), this, SLOT(updateGL()));
  QObject::connect(kfi_, SIGNAL(endReached()), this, SLOT(simplePlay()));

  undoTimer_ = new QTimer();
#if QT_VERSION >= 0x040000
  undoTimer_->setSingleShot(true);
#endif
  QObject::connect(undoTimer_, SIGNAL(timeout()), this, SLOT(playNextMove()));

  for(int i = 0; i < 2; ++i)
    connect(&(computerPlayer_[i]), SIGNAL(moveMade(QString, int)), this, SLOT(playComputerMove(QString, int)));

  computerPlayer_[0].setIsActive(false);
  computerPlayer_[1].setIsActive(false);

  QStringList programFileNames;
  programFileNames << "agoraAI"
                   << "agoraAI.exe"
                   << "../AI/agoraAI"
                   << "../../AI/release/agoraAI.exe"
                   << "../../AI/debug/agoraAI.exe"
                   << "../AI/release/agoraAI.exe"
                   << "../AI/debug/agoraAI.exe";
  for(int i = 0; i < programFileNames.size(); ++i) {
    if(QFileInfo(programFileNames.at(i)).isExecutable()) {
      for(int c = 0; c < 2; ++c)
        computerPlayer_[c].setProgramFileName(programFileNames.at(i));
      break;
    }
  }
}

// I n i t i a l i z a t i o n   f u n c t i o n s

void AgoraViewer::init()
{
  initViewer();
  initSpotLight();
  initBoard();
  fitCameraToBoard();

  setMouseBinding(Qt::RightButton, CAMERA, ROTATE);
  setMouseBinding(Qt::LeftButton, SELECT);

#if QT_VERSION >= 0x040000
  // Signals and slots connections
  AgoraWindow* agoWin = (AgoraWindow*)(window());
  connect(agoWin->fileExitAction, SIGNAL(activated()), agoWin, SLOT(close()));
  connect(agoWin->fileOpenAction, SIGNAL(activated()), this, SLOT(load()));
  connect(agoWin->fileSaveAction, SIGNAL(activated()), this, SLOT(save()));
  connect(agoWin->fileSaveAsAction, SIGNAL(activated()), this, SLOT(saveAs()));
  connect(agoWin->gameNewGameAction, SIGNAL(activated()), this, SLOT(newGame()));
  connect(agoWin->gameUndoAction, SIGNAL(activated()), this, SLOT(undo()));
  connect(agoWin->gameRedoAction, SIGNAL(activated()), this, SLOT(redo()));

  connect(agoWin->gameBlackIsHumanAction, SIGNAL(toggled(bool)), this, SLOT(blackPlayerIsHuman(bool)));
  connect(agoWin->gameWhiteIsHumanAction, SIGNAL(toggled(bool)), this, SLOT(whitePlayerIsHuman(bool)));

  connect(agoWin->gameBlackIsHumanAction, SIGNAL(toggled(bool)), agoWin->gameConfigureBlackPlayerAction,
          SLOT(setDisabled(bool)));
  connect(agoWin->gameWhiteIsHumanAction, SIGNAL(toggled(bool)), agoWin->gameConfigureWhitePlayerAction,
          SLOT(setDisabled(bool)));

  connect(agoWin->gameConfigureBlackPlayerAction, SIGNAL(activated()), this, SLOT(configureBlackPlayer()));
  connect(agoWin->gameConfigureWhitePlayerAction, SIGNAL(activated()), this, SLOT(configureWhitePlayer()));

  connect(agoWin->togglePossibleMoveAction, SIGNAL(toggled(bool)), this, SLOT(toggleDisplayPossibleMoves(bool)));
  connect(agoWin->toggleAnimationAction, SIGNAL(toggled(bool)), this, SLOT(toggleAnimation(bool)));

  connect(agoWin->helpAboutAction, SIGNAL(activated()), this, SLOT(about()));
  connect(agoWin->helpRulesAction, SIGNAL(activated()), this, SLOT(displayRules()));
#endif
}

void AgoraViewer::initViewer()
{
  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

  // Enable GL textures
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

  // Nice texture coordinate interpolation
  glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);

  const QString texFileName("wood.png");
  QImage img(texFileName);

  if(img.isNull()) {
    QMessageBox::warning(NULL, QString("Texture file not found"),
                         QString("Unable to load wood texture (%1).").arg(texFileName));
    return;
  }

  // 1E-3 needed. Just try with width=128 and see !
  if((img.width() != 1 << (int)(1 + log(img.width() - 1 + 1E-3) / log(2.0)))
     || (img.height() != 1 << (int)(1 + log(img.height() - 1 + 1E-3) / log(2.0)))) {
    QMessageBox::warning(NULL, QString("Incorrect texture"),
                         QString("Wood texture dimensions are not powers of 2."));
    return;
  }

  QImage glImg = QGLWidget::convertToGLFormat(img);   // flipped 32bit RGBA

  // Bind the img texture...
  glTexImage2D(GL_TEXTURE_2D, 0, 4, glImg.width(), glImg.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, glImg.bits());
  glDisable(GL_TEXTURE_2D);
}

void AgoraViewer::initBoard()
{
  board_ = new Board();

  QStringList boardDir;
  boardFileName_ = "";
  boardDir << "AgoraBoards"
           << "../AgoraBoards"
           << "../../AgoraBoards";
  for(int i = 0; i < boardDir.size(); ++i) {
    if(QFileInfo(boardDir.at(i)).isDir()) {
      boardFileName_ = boardDir.at(i) + "/standard.ago";
      break;
    }
  }

  if(boardFileName_.isEmpty()) {
    QMessageBox::warning(NULL, "Unable to find agora board directory",
                         "Unable to find agora board directory\n(tried " + boardDir.join(", ") + ")");
    return;
  }

  newGame();
}

void AgoraViewer::initSpotLight()
{
  glMatrixMode(GL_MODELVIEW);
  glEnable(GL_LIGHT1);
  glLoadIdentity();

  // Light default parameters
  const GLfloat light_ambient[4] = { 2.0, 2.0, 2.0, 1.0 };
  const GLfloat light_specular[4] = { 1.0, 1.0, 1.0, 1.0 };
  const GLfloat light_diffuse[4] = { 2.0, 2.0, 2.0, 1.0 };

  glLightf(GL_LIGHT1, GL_SPOT_EXPONENT, 2.0);
  glLightf(GL_LIGHT1, GL_SPOT_CUTOFF, 60.0);
  glLightf(GL_LIGHT1, GL_CONSTANT_ATTENUATION, 0.1f);
  glLightf(GL_LIGHT1, GL_LINEAR_ATTENUATION, 0.3f);
  glLightf(GL_LIGHT1, GL_QUADRATIC_ATTENUATION, 0.3f);
  glLightfv(GL_LIGHT1, GL_AMBIENT, light_ambient);
  glLightfv(GL_LIGHT1, GL_SPECULAR, light_specular);
  glLightfv(GL_LIGHT1, GL_DIFFUSE, light_diffuse);
}

void AgoraViewer::newGame()
{
  if(!QFileInfo(boardFileName_).isReadable()) {
    QMessageBox::warning(NULL, "Unreadable board file",
                         "Unable to read board file (" + boardFileName_ + ").\nLoad another board.");
    return;
  }

#if QT_VERSION < 0x040000
  std::ifstream f(boardFileName_.latin1());
#else
  std::ifstream f(boardFileName_.toLatin1().constData());
#endif
  f >> *board_;
  f.close();

  selectedPiece_ = -1;

  playNextMove();
}

void AgoraViewer::fitCameraToBoard()
{
  static BoardConstraint* boardConstraint = new BoardConstraint();

  // Free camera rotation motion
  camera()->frame()->setConstraint(NULL);

  setSceneCenter(Vec(board_->size().width() / 2.0, board_->size().height() / 2.0, 0.0));
  setSceneRadius(sceneCenter().norm());

  camera()->setUpVector(Vec(0.0, 0.0, 1.0));
  camera()->setPosition(
    Vec(2.0f * sceneCenter().x, -1.5f * sceneCenter().y, 0.9f * (sceneCenter().x + sceneCenter().y)));
  camera()->lookAt(sceneCenter());
  // showEntireScene();

  // Limit camera rotation motion
  camera()->frame()->setConstraint(boardConstraint);
}

// D r a w i n g   f u n c t i o n s
void AgoraViewer::draw()
{
  glEnable(GL_LIGHTING);

  if(animationStep_ > 0) {
    glPushMatrix();
    glMultMatrixd(kfi_->frame()->matrix());
    // Board::drawPiece(board_->blackPlays());
    glPopMatrix();

    // if (animationStep_ > 1)
    //	board_->drawFlippingPieces(currentMove_.end(), animationStep_%2);
  }

  const GLfloat pos[4] = { board_->size().width() / 2.0, board_->size().height() / 2.0, 3.0, 1.0 };
  const GLfloat spot_dir[3] = { 0.0, 0.0, -1.0 };
  glLightfv(GL_LIGHT1, GL_POSITION, pos);
  glLightfv(GL_LIGHT1, GL_SPOT_DIRECTION, spot_dir);

  board_->draw();

  if(selectedPiece_ >= 0) {
    board_->drawSelectedPiece(selectedPiece_);
    if(displayPossibleMoves_)
      board_->drawPossibleDestinations(selectedPiece_);
  }
}

// G a m e   I n t e r f a c e
void AgoraViewer::play(const Move& m)
{
  currentMove_ = m;
  if(animatePlays_)
    animatePlay();
  else
    simplePlay();
}

void AgoraViewer::simplePlay()
{
  board_->play(currentMove_);
  updateGL();
  playNextMove();
}

void AgoraViewer::playNextMove()
{
  static const QString stateFileName = "board.ago";

// Updates statusBar
#if QT_VERSION < 0x040000
  ((QMainWindow*)(((QWidget*)parent())->parent()))->statusBar()->message(board_->statusMessage());
#else
  ((QMainWindow*)(((QWidget*)parent())->parent()))->statusBar()->showMessage(board_->statusMessage());
#endif

  if(board_->gameIsOver())
    QMessageBox::information(this, "Game over", board_->statusMessage());
  else {
// Save board state
#if QT_VERSION < 0x040000
    std::ofstream f(stateFileName.latin1());
#else
    std::ofstream f(stateFileName.toLatin1().constData());
#endif
    f << *board_;
    f.close();

    computerPlayer_[board_->blackPlays()].play(board_->blackPlays(), stateFileName, board_->nbMovesLeft());
  }
}

void AgoraViewer::playComputerMove(QString move, int duration)
{
  QString message = colorString[board_->blackPlays()] + " program played %1 in %2 out of %3 seconds.";
  message = message.arg(move).arg(duration / 1000.0, 0, 'f', 1).arg(
      computerPlayer_[board_->blackPlays()].allowedTime() / 1000.0, 0, 'f', 1);
#if QT_VERSION < 0x040000
  qWarning(message.latin1());
#else
  qWarning("%s", message.toLatin1().constData());
#endif
  Move m(move);
  if(m.isValid(board_))
    play(m);
  else
    QMessageBox::warning(this, "Unvalid move",
                         "The move " + move + " is not valid for " + colorString[board_->blackPlays()]);
}

void AgoraViewer::animatePlay()
{
  kfi_->deletePath();
  // Cut/pasted from board posOf(). Not shared to prevent QGLViewer dependency in board.h

  //	kfi_->addKeyFrame(Frame(Vec(currentMove_.start().x()+0.5,currentMove_.start().y()+0.5,0.0), Quaternion()));
  //	kfi_->addKeyFrame(Frame(Vec((currentMove_.start().x()+currentMove_.end().x()+1.0)/2.0,
  //		(currentMove_.start().y()+currentMove_.end().y()+1.0)/2.0, 1.0), Quaternion()), 0.6f);
  //  kfi_->addKeyFrame(Frame(Vec(currentMove_.end().x()+0.5,currentMove_.end().y()+0.5,0.0), Quaternion()), 1.2f);
  kfi_->addKeyFrame(Frame(Vec(currentMove_.end().x() + 0.5, currentMove_.end().y() + 0.5, 0.0), Quaternion()));

  animationStep_ = 1;
  kfi_->startInterpolation();
}

// M o v e   S e l e c t i o n
void AgoraViewer::drawWithNames()
{
  // Selection enabled only when the computer program is not active
  if((!computerPlayer_[board_->blackPlays()].isActive()) && (animationStep_ == 0)) {
    if(selectedPiece_ >= 0)
      board_->drawPossibleDestinations(selectedPiece_, true);

    // Always drawned, so that a new selection can occur
    board_->drawSelectablePieces();
  }
}

void AgoraViewer::postSelection(const QPoint&)
{
  if(selectedPiece_ >= 0) {
    if(selectedName() >= 0)
      if(selectedName() == selectedPiece_)
        selectedPiece_ = -1;
      else {
        Move m(board_, selectedPiece_, selectedName(), qApp->keyboardModifiers() != Qt::NoModifier);
        if(m.isValid(board_)) {
          selectedPiece_ = -1;
          play(m);
        } else if(board_->canBeSelected(selectedName()))
          selectedPiece_ = selectedName();
        else
          selectedPiece_ = -1;
      }
    else
      selectedPiece_ = -1;
  } else if(selectedName() >= 0)
    selectedPiece_ = selectedName();
}

// F i l e   m e n u   f u n c t i o n s
void AgoraViewer::selectBoardFileName()
{
#if QT_VERSION < 0x040000
  boardFileName_ = QFileDialog::getOpenFileName("Boards", "Agora files (*.ago);;All files (*)", this);
#else
  boardFileName_ = QFileDialog::getOpenFileName(this, "Select a saved game", boardFileName_,
                                                "Agora files (*.ago);;All files (*)");
#endif
}

void AgoraViewer::load()
{
  selectBoardFileName();

  // In case of Cancel
  if(boardFileName_.isEmpty())
    return;

  newGame();
  fitCameraToBoard();
}

void AgoraViewer::save()
{
#if QT_VERSION < 0x040000
  std::ofstream f(boardFileName_.latin1());
#else
  std::ofstream f(boardFileName_.toLatin1().constData());
#endif
  f << *board_;
  f.close();
}

void AgoraViewer::saveAs()
{
#if QT_VERSION < 0x040000
  boardFileName_
    = QFileDialog::getSaveFileName("Boards", "Agora files (*.ago);;All files (*)", this, boardFileName_.latin1());
#else
  boardFileName_
    = QFileDialog::getSaveFileName(this, "Save game", boardFileName_, "Agora files (*.ago);;All files (*)");
#endif

  QFileInfo fi(boardFileName_);

#if QT_VERSION < 0x040000
  if(fi.extension().isEmpty())
#else
  if(fi.suffix().isEmpty())
#endif
  {
    boardFileName_ += ".ago";
    fi.setFile(boardFileName_);
  }

#if QT_VERSION < 0x040000
  if(fi.exists()) {
    if(QMessageBox::warning(this, "Existing file", "File " + fi.fileName() + " already exists.\nSave anyway ?",
                            QMessageBox::Yes, QMessageBox::Cancel) == QMessageBox::Cancel)
      return;

    if(!fi.isWritable()) {
      QMessageBox::warning(this, "Cannot save", "File " + fi.fileName() + " is not writeable.");
      return;
    }
  }
#endif

  save();
}

// G a m e   m e n u   m e t h o d s

void AgoraViewer::blackPlayerIsHuman(bool on) {
  setPlayerIsHuman(on, true);
}

void AgoraViewer::whitePlayerIsHuman(bool on) {
  setPlayerIsHuman(on, false);
}

void AgoraViewer::configureBlackPlayer() {
  configurePlayer(true);
}

void AgoraViewer::configureWhitePlayer() {
  configurePlayer(false);
}

void AgoraViewer::setPlayerIsHuman(bool on, bool black)
{
  computerPlayer_[black].setIsActive(!on);
  playNextMove();
}

void AgoraViewer::configurePlayer(bool black) {
  computerPlayer_[black].configure();
}

// U n d o   a n d   R e do
void AgoraViewer::undo()
{
  if((animationStep_ == 0) && (board_->undo()))
    finalizeUndoRedo();
}

void AgoraViewer::redo()
{
  if((animationStep_ == 0) && (board_->redo()))
    finalizeUndoRedo();
}

void AgoraViewer::finalizeUndoRedo()
{
  selectedPiece_ = -1;
  updateGL();
#if QT_VERSION < 0x040000
  undoTimer_->start(1000, true);
#else
  undoTimer_->start(1000);
#endif
}

void AgoraViewer::about()
{
  QMessageBox::about(this, "A g o  r a", "A g o r a\nCreated by Gilles Debunne\nVersion 2.0 - January 2008");
}

void AgoraViewer::displayRules()
{
  static QTextEdit* te;

  static const QString rules
    = "<b>A g o r a</b><br><br>"
      "Agora is a strategy game for two players.<br><br>"
      "The goal is to have the maximum number of pieces of your color when the number of allowed moves is reached "
      "(or to convert all the pieces into your color before that).<br><br>"
      "A piece can be moved on a nearby square... "
      "details to come.<br><br>"
      "Enjoy !";

  if(!te) {
    te = new QTextEdit(rules);
    te->resize(500, 300);
  }

  te->show();
}
