/*
 * LibrePCB - Professional EDA for everyone!
 * Copyright (C) 2013 LibrePCB Developers, see AUTHORS.md for contributors.
 * https://librepcb.org/
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/*******************************************************************************
 *  Includes
 ******************************************************************************/
#include "packageeditorfsm.h"

#include "../../../widgets/graphicsview.h"
#include "../footprintgraphicsitem.h"
#include "packageeditorstate_addholes.h"
#include "packageeditorstate_addnames.h"
#include "packageeditorstate_addpads.h"
#include "packageeditorstate_addvalues.h"
#include "packageeditorstate_drawarc.h"
#include "packageeditorstate_drawcircle.h"
#include "packageeditorstate_drawline.h"
#include "packageeditorstate_drawpolygon.h"
#include "packageeditorstate_drawrect.h"
#include "packageeditorstate_drawtext.h"
#include "packageeditorstate_measure.h"
#include "packageeditorstate_select.h"

#include <librepcb/core/application.h>
#include <librepcb/core/graphics/graphicsscene.h>
#include <librepcb/core/graphics/primitivetextgraphicsitem.h>
#include <librepcb/core/library/pkg/footprint.h>
#include <librepcb/core/library/pkg/package.h>

#include <QtCore>

/*******************************************************************************
 *  Namespace
 ******************************************************************************/
namespace librepcb {
namespace editor {

/*******************************************************************************
 *  Constructors / Destructor
 ******************************************************************************/

PackageEditorFsm::PackageEditorFsm(const Context& context) noexcept
  : QObject(nullptr),
    mContext(context),
    mCurrentState(State::IDLE),
    mPreviousState(State::IDLE) {
  mStates.insert(State::SELECT, new PackageEditorState_Select(mContext));
  mStates.insert(State::ADD_THT_PADS,
                 new PackageEditorState_AddPadsTht(mContext));
  mStates.insert(State::ADD_SMT_PADS,
                 new PackageEditorState_AddPadsSmt(mContext));
  mStates.insert(State::ADD_NAMES, new PackageEditorState_AddNames(mContext));
  mStates.insert(State::ADD_VALUES, new PackageEditorState_AddValues(mContext));
  mStates.insert(State::DRAW_LINE, new PackageEditorState_DrawLine(mContext));
  mStates.insert(State::DRAW_RECT, new PackageEditorState_DrawRect(mContext));
  mStates.insert(State::DRAW_POLYGON,
                 new PackageEditorState_DrawPolygon(mContext));
  mStates.insert(State::DRAW_CIRCLE,
                 new PackageEditorState_DrawCircle(mContext));
  mStates.insert(State::DRAW_ARC, new PackageEditorState_DrawArc(mContext));
  mStates.insert(State::DRAW_TEXT, new PackageEditorState_DrawText(mContext));
  mStates.insert(State::ADD_HOLES, new PackageEditorState_AddHoles(mContext));
  mStates.insert(State::MEASURE, new PackageEditorState_Measure(mContext));

  foreach (PackageEditorState* state, mStates) {
    connect(state, &PackageEditorState::statusBarMessageChanged, this,
            &PackageEditorFsm::statusBarMessageChanged);
  }

  enterNextState(State::SELECT);
}

PackageEditorFsm::~PackageEditorFsm() noexcept {
  leaveCurrentState();
  qDeleteAll(mStates);
  mStates.clear();
}

/*******************************************************************************
 *  Getters
 ******************************************************************************/

EditorWidgetBase::Tool PackageEditorFsm::getCurrentTool() const noexcept {
  switch (mCurrentState) {
    case State::IDLE:
      return EditorWidgetBase::Tool::NONE;
    case State::SELECT:
      return EditorWidgetBase::Tool::SELECT;
    case State::ADD_THT_PADS:
      return EditorWidgetBase::Tool::ADD_THT_PADS;
    case State::ADD_SMT_PADS:
      return EditorWidgetBase::Tool::ADD_SMT_PADS;
    case State::ADD_NAMES:
      return EditorWidgetBase::Tool::ADD_NAMES;
    case State::ADD_VALUES:
      return EditorWidgetBase::Tool::ADD_VALUES;
    case State::DRAW_LINE:
      return EditorWidgetBase::Tool::DRAW_LINE;
    case State::DRAW_ARC:
      return EditorWidgetBase::Tool::DRAW_ARC;
    case State::DRAW_RECT:
      return EditorWidgetBase::Tool::DRAW_RECT;
    case State::DRAW_POLYGON:
      return EditorWidgetBase::Tool::DRAW_POLYGON;
    case State::DRAW_CIRCLE:
      return EditorWidgetBase::Tool::DRAW_CIRCLE;
    case State::DRAW_TEXT:
      return EditorWidgetBase::Tool::DRAW_TEXT;
    case State::ADD_HOLES:
      return EditorWidgetBase::Tool::ADD_HOLES;
    case State::MEASURE:
      return EditorWidgetBase::Tool::MEASURE;
    default:
      Q_ASSERT(false);
      return EditorWidgetBase::Tool::NONE;
  }
}

std::shared_ptr<Footprint> PackageEditorFsm::getCurrentFootprint() const
    noexcept {
  return mContext.currentFootprint;
}

/*******************************************************************************
 *  General Methods
 ******************************************************************************/

void PackageEditorFsm::updateAvailableFeatures() noexcept {
  QSet<EditorWidgetBase::Feature> features;
  if (PackageEditorState* state = getCurrentState()) {
    features |= state->getAvailableFeatures();
  }
  if (features != mAvailableFeatures) {
    mAvailableFeatures = features;
    emit availableFeaturesChanged();
  }
}

/*******************************************************************************
 *  Event Handlers
 ******************************************************************************/

bool PackageEditorFsm::processChangeCurrentFootprint(
    const std::shared_ptr<Footprint>& fpt) noexcept {
  if (fpt == mContext.currentFootprint) return false;

  // leave current state before changing the footprint because
  State previousState = mCurrentState;
  if (!leaveCurrentState()) {
    return false;
  }

  mContext.currentFootprint = fpt;
  if (mContext.currentFootprint) {
    // load graphics items recursively
    mContext.currentGraphicsItem.reset(new FootprintGraphicsItem(
        mContext.currentFootprint, mContext.editorContext.layerProvider,
        qApp->getDefaultStrokeFont(), &mContext.package.getPads()));
    mContext.graphicsScene.addItem(*mContext.currentGraphicsItem);
    mSelectFootprintGraphicsItem.reset();
    mContext.graphicsView.setEnabled(true);
    mContext.graphicsView.zoomAll();

    // restore previous state
    return setNextState(previousState);
  } else {
    mContext.currentGraphicsItem.reset();
    mSelectFootprintGraphicsItem.reset(new PrimitiveTextGraphicsItem());
    mSelectFootprintGraphicsItem->setHeight(PositiveLength(Length::fromMm(5)));
    mSelectFootprintGraphicsItem->setText(tr("Please select a footprint."));
    mSelectFootprintGraphicsItem->setLayer(
        mContext.editorContext.layerProvider.getLayer(
            GraphicsLayer::sBoardOutlines));
    mContext.graphicsScene.addItem(*mSelectFootprintGraphicsItem);
    mContext.graphicsView.setEnabled(false);
    mContext.graphicsView.zoomAll();

    // go to selection tool because other tools may no longer work properly!
    return setNextState(State::SELECT);
  }
}

bool PackageEditorFsm::processKeyPressed(const QKeyEvent& e) noexcept {
  if (getCurrentState() && mContext.currentFootprint &&
      mContext.currentGraphicsItem) {
    return getCurrentState()->processKeyPressed(e);
  } else {
    return false;
  }
}

bool PackageEditorFsm::processKeyReleased(const QKeyEvent& e) noexcept {
  if (getCurrentState() && mContext.currentFootprint &&
      mContext.currentGraphicsItem) {
    return getCurrentState()->processKeyReleased(e);
  } else {
    return false;
  }
}

bool PackageEditorFsm::processGraphicsSceneMouseMoved(
    QGraphicsSceneMouseEvent& e) noexcept {
  if (getCurrentState() && mContext.currentFootprint &&
      mContext.currentGraphicsItem) {
    return getCurrentState()->processGraphicsSceneMouseMoved(e);
  } else {
    return false;
  }
}

bool PackageEditorFsm::processGraphicsSceneLeftMouseButtonPressed(
    QGraphicsSceneMouseEvent& e) noexcept {
  if (getCurrentState() && mContext.currentFootprint &&
      mContext.currentGraphicsItem) {
    return getCurrentState()->processGraphicsSceneLeftMouseButtonPressed(e);
  } else {
    return false;
  }
}

bool PackageEditorFsm::processGraphicsSceneLeftMouseButtonReleased(
    QGraphicsSceneMouseEvent& e) noexcept {
  if (getCurrentState() && mContext.currentFootprint &&
      mContext.currentGraphicsItem) {
    return getCurrentState()->processGraphicsSceneLeftMouseButtonReleased(e);
  } else {
    return false;
  }
}

bool PackageEditorFsm::processGraphicsSceneLeftMouseButtonDoubleClicked(
    QGraphicsSceneMouseEvent& e) noexcept {
  if (getCurrentState() && mContext.currentFootprint &&
      mContext.currentGraphicsItem) {
    return getCurrentState()->processGraphicsSceneLeftMouseButtonDoubleClicked(
        e);
  } else {
    return false;
  }
}

bool PackageEditorFsm::processGraphicsSceneRightMouseButtonReleased(
    QGraphicsSceneMouseEvent& e) noexcept {
  PackageEditorState* state = getCurrentState();
  if (state && mContext.currentFootprint && mContext.currentGraphicsItem) {
    if (state->processGraphicsSceneRightMouseButtonReleased(e)) {
      return true;
    } else if (mCurrentState != State::SELECT) {
      // If right click is not handled, abort current command.
      return processAbortCommand();
    } else {
      // In select state, switch back to last state.
      return switchToPreviousState();
    }
  } else {
    return false;
  }
}

bool PackageEditorFsm::processSelectAll() noexcept {
  if (getCurrentState()) {
    return getCurrentState()->processSelectAll();
  } else {
    return false;
  }
}

bool PackageEditorFsm::processCut() noexcept {
  if (getCurrentState()) {
    return getCurrentState()->processCut();
  } else {
    return false;
  }
}

bool PackageEditorFsm::processCopy() noexcept {
  if (getCurrentState()) {
    return getCurrentState()->processCopy();
  } else {
    return false;
  }
}

bool PackageEditorFsm::processPaste() noexcept {
  if (getCurrentState()) {
    return getCurrentState()->processPaste();
  } else {
    return false;
  }
}

bool PackageEditorFsm::processMove(Qt::ArrowType direction) noexcept {
  if (getCurrentState() && mContext.currentFootprint &&
      mContext.currentGraphicsItem) {
    return getCurrentState()->processMove(direction);
  } else {
    return false;
  }
}

bool PackageEditorFsm::processRotate(const Angle& rotation) noexcept {
  if (getCurrentState() && mContext.currentFootprint &&
      mContext.currentGraphicsItem) {
    return getCurrentState()->processRotate(rotation);
  } else {
    return false;
  }
}

bool PackageEditorFsm::processMirror(Qt::Orientation orientation) noexcept {
  if (getCurrentState() && mContext.currentFootprint &&
      mContext.currentGraphicsItem) {
    return getCurrentState()->processMirror(orientation);
  } else {
    return false;
  }
}

bool PackageEditorFsm::processFlip(Qt::Orientation orientation) noexcept {
  if (getCurrentState() && mContext.currentFootprint &&
      mContext.currentGraphicsItem) {
    return getCurrentState()->processFlip(orientation);
  } else {
    return false;
  }
}

bool PackageEditorFsm::processSnapToGrid() noexcept {
  if (getCurrentState()) {
    return getCurrentState()->processSnapToGrid();
  } else {
    return false;
  }
}

bool PackageEditorFsm::processRemove() noexcept {
  if (getCurrentState() && mContext.currentFootprint &&
      mContext.currentGraphicsItem) {
    return getCurrentState()->processRemove();
  } else {
    return false;
  }
}

bool PackageEditorFsm::processEditProperties() noexcept {
  if (getCurrentState()) {
    return getCurrentState()->processEditProperties();
  } else {
    return false;
  }
}

bool PackageEditorFsm::processAbortCommand() noexcept {
  if (getCurrentState() && (!getCurrentState()->processAbortCommand())) {
    return setNextState(State::SELECT);
  } else {
    return false;
  }
}

bool PackageEditorFsm::processStartSelecting() noexcept {
  return setNextState(State::SELECT);
}

bool PackageEditorFsm::processStartAddingFootprintThtPads() noexcept {
  return setNextState(State::ADD_THT_PADS);
}

bool PackageEditorFsm::processStartAddingFootprintSmtPads() noexcept {
  return setNextState(State::ADD_SMT_PADS);
}

bool PackageEditorFsm::processStartAddingNames() noexcept {
  return setNextState(State::ADD_NAMES);
}

bool PackageEditorFsm::processStartAddingValues() noexcept {
  return setNextState(State::ADD_VALUES);
}

bool PackageEditorFsm::processStartDrawLines() noexcept {
  return setNextState(State::DRAW_LINE);
}

bool PackageEditorFsm::processStartDrawArcs() noexcept {
  return setNextState(State::DRAW_ARC);
}

bool PackageEditorFsm::processStartDrawRects() noexcept {
  return setNextState(State::DRAW_RECT);
}

bool PackageEditorFsm::processStartDrawPolygons() noexcept {
  return setNextState(State::DRAW_POLYGON);
}

bool PackageEditorFsm::processStartDrawCircles() noexcept {
  return setNextState(State::DRAW_CIRCLE);
}

bool PackageEditorFsm::processStartDrawTexts() noexcept {
  return setNextState(State::DRAW_TEXT);
}

bool PackageEditorFsm::processStartAddingHoles() noexcept {
  return setNextState(State::ADD_HOLES);
}

bool PackageEditorFsm::processStartDxfImport() noexcept {
  setNextState(State::SELECT);
  if (PackageEditorState* state = getCurrentState()) {
    if (state->processImportDxf()) {
      return true;
    }
  }
  return false;
}

bool PackageEditorFsm::processStartMeasure() noexcept {
  return setNextState(State::MEASURE);
}

/*******************************************************************************
 *  Private Methods
 ******************************************************************************/

PackageEditorState* PackageEditorFsm::getCurrentState() const noexcept {
  return mStates.value(mCurrentState, nullptr);
}

bool PackageEditorFsm::setNextState(State state) noexcept {
  if (state == mCurrentState) {
    return true;
  }
  if (state != State::SELECT && !mContext.currentFootprint) {
    return false;  // do not enter tools other than "select" if no footprint is
                   // selected!
  }
  if (!leaveCurrentState()) {
    return false;
  }
  const bool success = enterNextState(state);
  updateAvailableFeatures();
  return success;
}

bool PackageEditorFsm::leaveCurrentState() noexcept {
  if (PackageEditorState* state = getCurrentState()) {
    if (!state->exit()) {
      return false;
    }
    disconnect(state, &PackageEditorState::availableFeaturesChanged, this,
               &PackageEditorFsm::updateAvailableFeatures);
  }
  if (mCurrentState != State::SELECT) {
    // Only memorize states other than SELECT.
    mPreviousState = mCurrentState;
  }
  mCurrentState = State::IDLE;
  emit toolChanged(getCurrentTool());
  return true;
}

bool PackageEditorFsm::enterNextState(State state) noexcept {
  Q_ASSERT(mCurrentState == State::IDLE);
  if (PackageEditorState* nextState = mStates.value(state, nullptr)) {
    if (!nextState->entry()) {
      return false;
    }
    connect(nextState, &PackageEditorState::availableFeaturesChanged, this,
            &PackageEditorFsm::updateAvailableFeatures);
  }
  mCurrentState = state;
  emit toolChanged(getCurrentTool());
  return true;
}

bool PackageEditorFsm::switchToPreviousState() noexcept {
  State nextState = mPreviousState;
  if ((nextState == mCurrentState) || (nextState == State::IDLE)) {
    nextState = State::SELECT;
  }
  return setNextState(nextState);
}

/*******************************************************************************
 *  End of File
 ******************************************************************************/

}  // namespace editor
}  // namespace librepcb
