/*
 *  The Mana World
 *  Copyright 2004 The Mana World Development Team
 *
 *  This file is part of The Mana World.
 *
 *  The Mana World 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 2 of the License, or
 *  any later version.
 *
 *  The Mana World 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 The Mana World; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <cassert>

#include <guichan/sdl/sdlinput.hpp>

#include "gui.h"
#include "popupmenu.h"
#include "viewport.h"

#include "../beingmanager.h"
#include "../configuration.h"
#include "../flooritemmanager.h"
#include "../graphics.h"
#include "../keyboardconfig.h"
#include "../localplayer.h"
#include "../map.h"
#include "../monster.h"
#include "../npc.h"
#include "../textmanager.h"

#include "../resources/animation.h"
#include "../resources/image.h"
#include "../resources/imageset.h"
#include "../resources/monsterinfo.h"
#include "../resources/resourcemanager.h"

#include "../utils/tostring.h"

extern volatile int tick_time;

extern volatile int tick_time;

Viewport::Viewport():
    mMap(0),
    mPixelViewX(0.0f),
    mPixelViewY(0.0f),
    mTileViewX(0),
    mTileViewY(0),
    mShowDebugPath(false),
    mPlayerFollowMouse(false),
    mWalkTime(0)
{
    setOpaque(false);
    addMouseListener(this);

    mScrollLaziness = (int) config.getValue("ScrollLaziness", 32);
    mScrollRadius = (int) config.getValue("ScrollRadius", 32);
    mScrollCenterOffsetX = (int) config.getValue("ScrollCenterOffsetX", 0);
    mScrollCenterOffsetY = (int) config.getValue("ScrollCenterOffsetY", 0);

    config.addListener("ScrollLaziness", this);
    config.addListener("ScrollRadius", this);

    mPopupMenu = new PopupMenu();
}

Viewport::~Viewport()
{
    delete mPopupMenu;
}

void
Viewport::setMap(Map *map)
{
    mMap = map;
}

void
Viewport::draw(gcn::Graphics *gcnGraphics)
{
    static int lastTick = tick_time;

    if (!mMap || !player_node)
        return;

    Graphics *graphics = static_cast<Graphics*>(gcnGraphics);

    // Avoid freaking out when tick_time overflows
    if (tick_time < lastTick)
    {
        lastTick = tick_time;
    }

    // Calculate viewpoint
    int midTileX = (graphics->getWidth() + mScrollCenterOffsetX) / 32 / 2;
    int midTileY = (graphics->getHeight() + mScrollCenterOffsetY) / 32 / 2;

    int player_x = (player_node->mX - midTileX) * 32 +
                    player_node->getXOffset();
    int player_y = (player_node->mY - midTileY) * 32 +
                    player_node->getYOffset();

    if (mScrollLaziness < 1)
        mScrollLaziness = 1; // Avoids division by zero

    // Apply lazy scrolling
    while (lastTick < tick_time)
    {
        if (player_x > mPixelViewX + mScrollRadius)
        {
            mPixelViewX += (player_x - mPixelViewX - mScrollRadius) / mScrollLaziness;
        }
        if (player_x < mPixelViewX - mScrollRadius)
        {
            mPixelViewX += (player_x - mPixelViewX + mScrollRadius) / mScrollLaziness;
        }
        if (player_y > mPixelViewY + mScrollRadius)
        {
            mPixelViewY += (player_y - mPixelViewY - mScrollRadius) / mScrollLaziness;
        }
        if (player_y < mPixelViewY - mScrollRadius)
        {
            mPixelViewY += (player_y - mPixelViewY + mScrollRadius) / mScrollLaziness;
        }
        lastTick++;
    }

    // Auto center when player is off screen
    if (        player_x - mPixelViewX > graphics->getWidth() / 2
            ||  mPixelViewX - player_x > graphics->getWidth() / 2
            ||  mPixelViewY - player_y > graphics->getHeight() / 2
            ||  player_y - mPixelViewY > graphics->getHeight() / 2
        )
    {
        mPixelViewX = player_x;
        mPixelViewY = player_y;
    };

    // Don't move camera so that the end of the map is on screen
    int viewXmax = (mMap->getWidth() * 32) - graphics->getWidth();
    int viewYmax = (mMap->getHeight() * 32) - graphics->getHeight();
    if (mMap)
    {
        if (mPixelViewX < 0) {
            mPixelViewX = 0;
        }
        if (mPixelViewY < 0) {
            mPixelViewY = 0;
        }
        if (mPixelViewX > viewXmax) {
            mPixelViewX = viewXmax;
        }
        if (mPixelViewY > viewYmax) {
            mPixelViewY = viewYmax;
        }
    }

    mTileViewX = (int) (mPixelViewX + 16) / 32;
    mTileViewY = (int) (mPixelViewY + 16) / 32;

    // Draw tiles and sprites
    if (mMap)
    {
        mMap->draw(graphics, (int) mPixelViewX, (int) mPixelViewY);

        // Find a path from the player to the mouse, and draw it. This is for debug
        // purposes.
        if (mShowDebugPath) 
        {
            // Get the current mouse position
            int mouseX, mouseY;
            SDL_GetMouseState(&mouseX, &mouseY);

            int mouseTileX = mouseX / 32 + mTileViewX;
            int mouseTileY = mouseY / 32 + mTileViewY;

            Path debugPath = mMap->findPath(player_node->mX, player_node->mY, mouseTileX, mouseTileY);

            graphics->setColor(gcn::Color(255, 0, 0));
            for (PathIterator i = debugPath.begin(); i != debugPath.end(); i++)
            {
                int squareX = i->x * 32 - (int) mPixelViewX + 12;
                int squareY = i->y * 32 - (int) mPixelViewY + 12;

                graphics->fillRectangle(gcn::Rectangle(squareX, squareY, 8, 8));
                graphics->drawText(toString(mMap->getMetaTile(i->x, i->y)->Gcost), squareX + 4, squareY + 12, gcn::Graphics::CENTER);
            }
        }
    }

    // Draw text
    if (textManager)
    {
        textManager->draw(graphics, mPixelViewX, mPixelViewY);
    }

    // Draw player names, speech, and emotion sprite as needed
    Beings &beings = beingManager->getAll();
    for (BeingIterator i = beings.begin(); i != beings.end(); i++)
    {
        (*i)->drawEmotion(graphics, -(int) mPixelViewX, -(int) mPixelViewY);
    }

    // Draw contained widgets
    WindowContainer::draw(gcnGraphics);
}

void Viewport::logic()
{
    WindowContainer::logic();

    if (!mMap || !player_node)
        return;

    int mouseX, mouseY;
    Uint8 button = SDL_GetMouseState(&mouseX, &mouseY);

    if (mPlayerFollowMouse && button & SDL_BUTTON(1) &&
            mWalkTime != player_node->mWalkTime)
    {
        player_node->setDestination(mouseX / 32 + mTileViewX,
                                    mouseY / 32 + mTileViewY);
        mWalkTime = player_node->mWalkTime;
    }
}

void Viewport::mousePressed(gcn::MouseEvent &event)
{
    // Check if we are alive and kickin'
    if (!mMap || !player_node || player_node->mAction == Being::DEAD)
        return;

    // Check if we are busy
    if (current_npc)
        return;

    mPlayerFollowMouse = false;

    const int tilex = event.getX() / 32 + mTileViewX;
    const int tiley = event.getY() / 32 + mTileViewY;
    const int x = (int)((float) event.getX() + mPixelViewX);
    const int y = (int)((float) event.getY() + mPixelViewY);

    // Right click might open a popup
    if (event.getButton() == gcn::MouseEvent::RIGHT)
    {
        Being *being;
        FloorItem *floorItem;

        if ((being = beingManager->findBeingByPixel(x, y)) &&
             being != player_node)
        {
           mPopupMenu->showPopup(event.getX(), event.getY(), being);
           return;
        }
        else if((floorItem = floorItemManager->findByCoordinates(tilex, tiley)))
        {
            mPopupMenu->showPopup(event.getX(), event.getY(), floorItem);
            return;
        }
    }

    // If a popup is active, just remove it
    if (mPopupMenu->isVisible())
    {
        mPopupMenu->setVisible(false);
        return;
    }

    // Left click can cause different actions
    if (event.getButton() == gcn::MouseEvent::LEFT)
    {
        Being *being;
        FloorItem *item;
 
        // Interact with some being
//        if ((being = beingManager->findBeing(tilex, tiley)))
        if ((being = beingManager->findBeingByPixel(x, y)))
        {
            switch (being->getType())
            {
                case Being::NPC:
                    dynamic_cast<NPC*>(being)->talk();
                    break;

                case Being::MONSTER:
                case Being::PLAYER:
                    if (being->mAction == Being::DEAD)
                        break;

                    if (player_node->withinAttackRange(being) || keyboard.isKeyActive(keyboard.KEY_ATTACK))
                    {
                        player_node->setGotoTarget(being);
                        player_node->attack(being, !keyboard.isKeyActive(keyboard.KEY_TARGET));
                    }
                    else
                    {
                        player_node->setDestination(tilex, tiley);
                    }
                    break;

                default:
                    break;
             }
        }
        // Pick up some item
        else if ((item = floorItemManager->findByCoordinates(tilex, tiley)))
        {
            player_node->pickUp(item);
        }
        // Just walk around
        else
        {
            player_node->stopAttack();
            player_node->setDestination(tilex, tiley);
            mPlayerFollowMouse = true;
        }
    }
    else if (event.getButton() == gcn::MouseEvent::MIDDLE)
    {
        // Find the being nearest to the clicked position
        Being *target = beingManager->findBeingByPixel(x, y);
 
        if (target)
        {
             player_node->setTarget(target);
        }
    }
}

void Viewport::mouseDragged(gcn::MouseEvent &event)
{
    if (!mMap || !player_node)
        return;

    if (mPlayerFollowMouse && mWalkTime == player_node->mWalkTime)
    {
        int destX = event.getX() / 32 + mTileViewX;
        int destY = event.getY() / 32 + mTileViewY;
        player_node->setDestination(destX, destY);
    }
}

void Viewport::mouseReleased(gcn::MouseEvent &event)
{
    mPlayerFollowMouse = false;
}

void Viewport::showPopup(int x, int y, Item *item)
{
    mPopupMenu->showPopup(x, y, item);
}

void Viewport::optionChanged(const std::string &name)
{
    mScrollLaziness = (int) config.getValue("ScrollLaziness", 32);
    mScrollRadius = (int) config.getValue("ScrollRadius", 32);
}