#include "animatedsprite.hpp"
#include <array>
#include <cassert>
#include <fstream>
#include <sstream>

namespace Animation
{
	sf::IntRect Animation::GetFrame(unsigned frameNumber, bool const bounced) const
	{
		assert(frameNumber < frameCount);

		if(reverse != bounced)
			frameNumber = frameCount - (frameNumber + 1);
		unsigned const x = frameOrigin.x + (frameNumber * frameMargin.x) + (frameNumber * frameStep.x);
		unsigned const y = frameOrigin.y + (frameNumber * frameMargin.y) + (frameNumber * frameStep.y);
	
		return sf::IntRect(x, y, frameSize.x, frameSize.y);
	}

	Animation::Animation()
		: frameOrigin(0, 0),
		frameSize(0, 0),
		frameStep(0, 0),
		frameMargin(0, 0),
		frameCount(0),
		frameTime(0),
		reverse(false),
		loop(false),
		bounce(false)
	{}

	std::unordered_map<std::string, Animation> LoadFromFile(std::string const & filepath)
	{
		std::array<std::string, 9> const properties =
		{
			"frame-origin",
			"frame-size",
			"frame-step",
			"frame-margin",
			"frame-count",
			"frame-time",
			"reverse",
			"loop",
			"bounce"
		};

		std::unordered_map<std::string, Animation> animations;

		std::ifstream file(filepath);
		if(!file.is_open())
			return animations;
		
		Animation candidate;
		std::string candidateName;
		while(file.good())
		{
			std::string lineRaw;
			std::getline(file, lineRaw);
			if(lineRaw.size() == 0 || lineRaw[0] == '#')
				continue;
			
			std::stringstream line(lineRaw);
			std::string key;
			line >> key;
			
			if(lineRaw[0] == '\t' && candidateName.size() > 0)
			{
				for(std::size_t i = 0; i < properties.size(); ++i)
				{
					if(properties[i].compare(key) == 0)
					{
						switch(i)
						{
							case 0:
							line >> candidate.frameOrigin.x;
							line >> candidate.frameOrigin.y;
							break;

							case 1:
							line >> candidate.frameSize.x;
							line >> candidate.frameSize.y;
							break;

							case 2:
							line >> candidate.frameStep.x;
							line >> candidate.frameStep.y;
							break;

							case 3:
							line >> candidate.frameMargin.x;
							line >> candidate.frameMargin.y;
							break;

							case 4:
							line >> candidate.frameCount;
							break;

							case 5:
							line >> candidate.frameTime;
							break;

							case 6:
							candidate.reverse = true;
							break;

							case 7:
							candidate.loop = true;
							break;

							case 8:
							candidate.loop = true;
							candidate.bounce = true;
							break;
						}
						break;
					}
				}
			}
			else if(key.compare("animation") == 0)
			{
				if(candidateName.size() > 0)
				{
					animations[candidateName] = candidate;
				}
				candidate = Animation();
				line >> candidateName;
			}
			else
			{
				if(candidateName.size() > 0)
				{
					animations[candidateName] = candidate;
				}
				candidateName.resize(0);
			}
		}
		file.close();

		if(candidateName.size() > 0)
		{
			animations[candidateName] = candidate;
			candidateName.resize(0);
		}

		return animations;
	}
	
	void Sprite::SetFrame()
	{
		assert(currentAnimation != nullptr);
		
		sf::IntRect textureRect = currentAnimation->GetFrame(currentFrame, bouncing);
		if(isFlippedHorizontally)
		{
			textureRect.left += textureRect.width;
			textureRect.width *= -1;
		}
		if(isFlippedVertically)
		{
			textureRect.top += textureRect.height;
			textureRect.height *= -1;
		}
		setTextureRect(textureRect);
	}

	bool Sprite::IsAnimationFinished() const
	{
		assert(currentAnimation != nullptr);
		return currentFrame == (currentAnimation->frameCount - 1) && !currentAnimation->loop;
	}

	void Sprite::SetHorizontalFlip(const bool v)
	{
		if(v != isFlippedHorizontally)
		{
			isFlippedHorizontally = v;
			SetFrame();
		}
	}

	void Sprite::SetVerticalFlip(const bool v)
	{
		if(v != isFlippedVertically)
		{
			isFlippedVertically = v;
			SetFrame();
		}
	}

	bool Sprite::IsFlippedHorizontally() const
	{
		return isFlippedHorizontally;
	}

	bool Sprite::IsFlippedVertically() const
	{
		return isFlippedVertically;
	}

	void Sprite::ResetAnimation()
	{
		currentFrame = 0U;
		currentFrameTime = 0U;
		bouncing = false;
		SetFrame();
	}

	bool Sprite::SetAnimation(const std::string & name)
	{
		auto const candidate = animations.find(name);
		if(candidate == animations.cend())
		{
			return false;
		}
		
		currentAnimation = &(candidate->second);
		ResetAnimation();

		return true;
	}

	void Sprite::Update(const sf::Time & elapsed)
	{
		assert(currentAnimation != nullptr);

		if(IsAnimationFinished())
		{
			return;
		}

		currentFrameTime += elapsed.asMilliseconds();
		if(currentFrameTime < currentAnimation->frameTime)
		{
			return;
		}
		unsigned const steps = currentFrameTime / currentAnimation->frameTime;
		currentFrameTime -= currentAnimation->frameTime * steps;

		currentFrame += steps;
		if(currentFrame >= currentAnimation->frameCount)
		{
			currentFrame = currentFrame % currentAnimation->frameCount;
			if(currentAnimation->bounce)
				bouncing = !bouncing;
		}

		SetFrame();
	}

	void Sprite::UpdateFromOther(const Sprite & parent)
	{
		if(currentFrame != parent.currentFrame)
		{
			currentFrame = parent.currentFrame;
			bouncing = parent.bouncing;
			SetFrame();
		}
	}

	Sprite::Sprite(std::unordered_map<std::string, Animation> const & _animations,
			std::string const & animation,
			sf::Texture const & texture)
		: sf::Sprite(texture), 
		animations(_animations),
		currentAnimation(nullptr)
	{
		SetAnimation(animation);
	}
}