#include "../include/MessageBoard.hpp"
#include "../include/Settings.hpp"
#include "../include/ResourceCache.hpp"
#include "../include/Gif.hpp"
#include "../include/ChannelSidePanel.hpp"
#include "../include/UsersSidePanel.hpp"
#include "../include/ChannelTopPanel.hpp"
#include "../include/Chatbar.hpp"
#include "../include/ColorScheme.hpp"
#include <SFML/Graphics/RectangleShape.hpp>
#include <SFML/Graphics/Sprite.hpp>
#include <SFML/Window/Mouse.hpp>
#include <SFML/Graphics/Rect.hpp>
#include <SFML/Graphics/Text.hpp>
#include <cmath>

using namespace std;

namespace dchat
{
    struct LineColor
    {
        sf::Color sideColor, centerColor;
    };
    
    const float USERNAME_PADDING_BOTTOM = 0.0f;
    const float MESSAGE_PADDING_TOP = 25.0f;
    const float MESSAGE_PADDING_BOTTOM = 30.0f;
    
    const float PADDING_SIDE = 40.0f;
    const float PADDING_TOP = 0.0f;
    const float LINE_SIDE_PADDING = 20.0f;
    const float LINE_HEIGHT = 1.0f;
    
    const LineColor LINE_COLOR
    {
        .sideColor = ColorScheme::getBackgroundColor() + sf::Color(10, 10, 10),
        .centerColor = ColorScheme::getBackgroundColor() + sf::Color(10, 10, 10)
    };
    
    static void drawGradientLine(const sf::Vector2f &position, const sf::Vector2f &size, const LineColor &color, sf::RenderWindow &window)
    {
        sf::Vertex rectangle[] = 
        {
            sf::Vertex(position, color.sideColor),
            sf::Vertex(sf::Vector2f(position.x + size.x * 0.5f, position.y), color.centerColor),
            sf::Vertex(sf::Vector2f(position.x + size.x * 0.5f, position.y + size.y), color.centerColor),
            sf::Vertex(sf::Vector2f(position.x, position.y + size.y), color.sideColor),
            
            sf::Vertex(sf::Vector2f(position.x + size.x * 0.5f, position.y), color.centerColor),
            sf::Vertex(sf::Vector2f(position.x + size.x, position.y), color.sideColor),
            sf::Vertex(sf::Vector2f(position.x + size.x, position.y + size.y), color.sideColor),
            sf::Vertex(sf::Vector2f(position.x + size.x * 0.5f, position.y + size.y), color.centerColor)
        };
        window.draw(rectangle, 8, sf::Quads);
    }
    
    MessageBoard::MessageBoard(const sf::Vector2u &size) : 
        selectingText(false),
        leftMouseButtonPressed(false),
        scroll(0.0),
        scrollSpeed(0.0),
        totalHeight(0.0)
    {
        updateStaticContentTexture(size);
    }
    
    MessageBoard::~MessageBoard()
    {
        for(Message *message : messages)
        {
            delete message;
        }
    }
    
    void MessageBoard::updateStaticContentTexture(const sf::Vector2u &newSize)
    {
        //if(!staticContentTexture.create(newSize.x, newSize.y))
        //    throw std::runtime_error("Failed to create render target for message board!");
        dirty = true;
    }
    
    void MessageBoard::addMessage(Message *message)
    {
        messages.push_back(message);
        dirty = true;
    }
    
    void MessageBoard::processEvent(const sf::Event &event)
    {
        if(event.type == sf::Event::MouseButtonPressed)
        {
            if(event.mouseButton.button == sf::Mouse::Button::Left)
            {
                leftMouseButtonPressed = true;
                mousePos.x = event.mouseButton.x;
                mousePos.y = event.mouseButton.y;
            }
        }
        else if(event.type == sf::Event::MouseButtonReleased)
        {
            if(event.mouseButton.button == sf::Mouse::Button::Left)
            {
                leftMouseButtonPressed = false;
                mousePos.x = event.mouseButton.x;
                mousePos.y = event.mouseButton.y;
            }
        }
        else if(event.type == sf::Event::LostFocus)
        {
            leftMouseButtonPressed = false;
        }
        else if(event.type == sf::Event::MouseMoved)
        {
            mousePos.x = event.mouseMove.x;
            mousePos.y = event.mouseMove.y;
        }
        else if(event.type == sf::Event::MouseWheelScrolled && event.mouseWheelScroll.wheel == sf::Mouse::Wheel::VerticalWheel)
        {
            scrollSpeed += (event.mouseWheelScroll.delta * 30.0);
        }
        
        if(selectingText && !leftMouseButtonPressed)
        {
            selectingText = false;
        }
        else if(!selectingText && leftMouseButtonPressed)
        {
            selectingText = true;
            selectingTextStart.x = mousePos.x;
            selectingTextStart.y = mousePos.y;
        }
    }
    
    void MessageBoard::draw(sf::RenderWindow &window, Cache &cache)
    {
        auto windowSize = window.getSize();
        sf::Vector2f backgroundSizeWithoutPadding(floor(windowSize.x - ChannelSidePanel::getWidth() - UsersSidePanel::getWidth()), floor(windowSize.y - ChannelTopPanel::getHeight() - Chatbar::getHeight()));
        sf::Vector2u backgroundSize(floor(windowSize.x - ChannelSidePanel::getWidth() - UsersSidePanel::getWidth() - PADDING_SIDE * 2.0f), floor(windowSize.y - ChannelTopPanel::getHeight() - Chatbar::getHeight() - PADDING_TOP));
        sf::Vector2f backgroundPos(ChannelSidePanel::getWidth(), ChannelTopPanel::getHeight());
        
        //if(backgroundSize != staticContentTexture.getSize())
        //    updateStaticContentTexture(backgroundSize);
        
        // TODO: Remove this when dchat::Text can render to static and dynamic render target
        dirty = true;
        //if(dirty)
        //    staticContentTexture.clear(BACKGROUND_COLOR);
        
        sf::RectangleShape backgroundRect(backgroundSizeWithoutPadding);
        backgroundRect.setFillColor(ColorScheme::getBackgroundColor());
        backgroundRect.setPosition(ChannelSidePanel::getWidth(), ChannelTopPanel::getHeight());
        window.draw(backgroundRect);
        
        const sf::Font *usernameFont = ResourceCache::getFont("fonts/Roboto-Regular.ttf");
        
        double deltaTimeMicro = (double)frameTimer.getElapsedTime().asMicroseconds();
        frameTimer.restart();
        
        if(dirty)
        {
            sf::Vector2<double> position(ChannelSidePanel::getWidth(), ChannelTopPanel::getHeight() + PADDING_TOP);
            double startHeight = position.y;
            position.y += scroll;
            for(Message *message : messages)
            {
                position.y += MESSAGE_PADDING_TOP;
                sf::Text usernameText(message->user->getName(), *usernameFont, 20 * Settings::getScaling());
                float usernameTextHeight = usernameText.getFont()->getLineSpacing(usernameText.getCharacterSize());
                if(position.y + usernameTextHeight > 0.0f && position.y < backgroundPos.y + backgroundSize.y)
                {
                    usernameText.setFillColor(sf::Color(15, 192, 252));
                    usernameText.setPosition(sf::Vector2f(floor(position.x + PADDING_SIDE), floor(position.y)));
                    window.draw(usernameText);
                }
                position.y += usernameTextHeight + USERNAME_PADDING_BOTTOM;
                
                // No need to perform culling here, that is done in @Text draw function
                message->text.setCharacterSize(18 * Settings::getScaling());
                message->text.setMaxWidth(backgroundSize.x);
                message->text.setPosition(sf::Vector2f(floor(position.x + PADDING_SIDE), floor(position.y)));
                message->text.draw(window, cache);
                position.y += message->text.getHeight() + MESSAGE_PADDING_BOTTOM;
                
                if(position.y + LINE_HEIGHT > 0.0f && position.y < backgroundPos.y + backgroundSize.y)
                    drawGradientLine(sf::Vector2f(position.x + LINE_SIDE_PADDING, floor(position.y)), sf::Vector2f(backgroundSizeWithoutPadding.x - LINE_SIDE_PADDING * 2.0f, LINE_HEIGHT), LINE_COLOR, window);
            }
            totalHeight = (position.y - scroll) - startHeight;
        }
        
        scroll += scrollSpeed;
        scrollSpeed /= (deltaTimeMicro * 0.0001);
        
        double textOverflow = backgroundSize.y - totalHeight;
        if(scroll > 0.0 || textOverflow > 0.0)
        {
            scroll = 0.0;
            scrollSpeed = 0.0;
        }
        else if(textOverflow < 0.0 && scroll < textOverflow)
        {
            scroll = textOverflow;
            scrollSpeed = 0.0;
        }
        
        //staticContentTexture.display();
        dirty = false;
        
        // TODO: Save this, expensive to create on fly?
        //sf::Sprite textureSprite(staticContentTexture.getTexture());
        //textureSprite.setPosition(backgroundPos);
        //window.draw(textureSprite);
        
        if(!selectingText) return;
        
        sf::Vector2f selectionRectStart(min((float)mousePos.x, selectingTextStart.x), min((float)mousePos.y, selectingTextStart.y));
        sf::Vector2f selectionRectEnd(max((float)mousePos.x, selectingTextStart.x), max((float)mousePos.y, selectingTextStart.y));
        sf::FloatRect selectionRect(selectionRectStart, selectionRectEnd - selectionRectStart);
    }
}