#include "root.h"
#include "text.h"
#include "shader.h"
#include "texture.h"
#include "node.h"
#include "material.h"
#include "assetManager.h"

#include "glad.h"
#include <glfw3.h>
#include <iostream>
#include <algorithm>
#include <ft2build.h>
#include FT_FREETYPE_H

using namespace std;

namespace vb01{
	Text::Text(string fontPath, wstring e, u16 firstChar, u16 lastChar){
		font = (FontAsset*)AssetManager::getSingleton()->getAsset(fontPath);
		setEntry(e);
		//init();
		//applyFont(fontPath, firstChar, lastChar);
	}

	Text::~Text(){
		//glDeleteVertexArrays(1, &VAO);
		//glDeleteBuffers(1, &VBO);
	}

	void Text::init(){
		//glGenVertexArrays(1, &VAO);
		//glGenBuffers(1, &VBO);

		//glBindVertexArray(VAO);
		//glBindBuffer(GL_ARRAY_BUFFER, VBO);

		//glBufferData(GL_ARRAY_BUFFER, sizeof(float) * 6 * 4, NULL, GL_DYNAMIC_DRAW);
		//glEnableVertexAttribArray(0);
		//glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, 4 * sizeof(float), (void*)0);

		//glBindBuffer(GL_ARRAY_BUFFER, 0);
		//glBindVertexArray(0);
	}

	wstring Text::getEntry(){
		wstring entry;

		for(Character &charac : characters)
			entry += charac.ch;

		return entry;
	}

	void Text::setEntry(wstring entry){
		for(Character &ch : characters)
			delete ch.material;

		characters.clear();
		Vector3 scale = Vector3::VEC_IJK;

		for(wchar_t ch : entry){
			Material *mat = new Material(Root::getSingleton()->getGuiShader());
			mat->addTexUniform("glyphTexture", new Texture(font->path, ch), false, false);
			
			Character charac = Character(ch, mat);
			int numChars = characters.size();

			if(numChars > 0){
				const FontAsset::Glyph &glyph = font->getGlyph(ch);
				Vector2 currOffset = Vector2::VEC_ZERO;

				if(horizontal)
					currOffset = Vector2::VEC_I * (leftToRight ? 1 : -1) * glyph.size.x * scale.x;
				else
					currOffset = Vector2::VEC_J * glyph.size.y * scale.y;

				charac.offset = characters[numChars - 1].offset + currOffset;
			}

			characters.push_back(charac);
		}
	}

	//TODO ensure destruction of textures when unloading the asset
	void Text::applyFont(string fontPath, u16 firstChar, u16 lastChar){
		characters.clear();

		font = (FontAsset*)AssetManager::getSingleton()->getAsset(fontPath);

		for(u16 i = firstChar; i < lastChar; i++){

			/*
			Glyph c;
			c.ch = i;
			c.size = Vector2(face->glyph->bitmap.width, face->glyph->bitmap.rows);
			c.bearing = Vector2(face->glyph->bitmap_left, face->glyph->bitmap_top);
			c.advance = face->glyph->advance.x;
			c.texId = i;

			 */
			//characters.push_back(c);
		}
	}

	void Text::update(){
		//Root *root = Root::getSingleton();
		//int width = root->getWidth(), height = root->getHeight();

		//material->update();
		//Shader *shader = material->getShader();
		//shader->setVec2(Vector2(width, height), "screen");
		//shader->setVec3(node->getPosition(), "pos");

		//Vector2 advanceOffset = Vector2::VEC_ZERO;

		//for(int i = (leftToRight ? 0 : entry.length() - 1); (leftToRight ? (i < entry.length()) : (i >= 0)); (leftToRight ? i++ : i--)){
		//	Glyph *glyphPtr = getGlyph(entry[i]);

		//	if(!glyphPtr) continue;

		//	int glyphTexId = -1;

		//	for(int j = 0; j < font->glyphTextures.size(); j++)
		//		if(font->glyphTextures[j].first == glyphPtr->texId){
		//			glyphTexId = j;
		//			break;
		//		}

		//	Glyph glyph = *glyphPtr;
		//	prepareGlyphs(glyph, glyphTexId, advanceOffset);
		//	Vector2 size = glyph.size, bearing = glyph.bearing;

		//	if(horizontal)
		//		advanceOffset.x += node->getScale().x * (size.x + bearing.x);
		//	else
		//		advanceOffset.y += node->getScale().y * size.y;
		//}
	}

	/*
	void Text::prepareGlyphs(Glyph glyph, int glyphTexId, Vector2 advanceOffset){
		//Vector3 nodePos = node->getPosition(), scale = node->getScale();
		//Vector2 origin = Vector2(nodePos.x, nodePos.y) + (advanceOffset * scale);

		//Vector2 size = Vector2(glyph.size.x * scale.x, glyph.size.y * scale.y);
		//Vector2 bearing = Vector2(glyph.bearing.x * scale.x, glyph.bearing.y * scale.y);

		//float data[] = {
		//	origin.x + bearing.x, origin.y - bearing.y, 0, 0,
		//	origin.x + bearing.x + size.x, origin.y - bearing.y, 1, 0,
		//	origin.x + bearing.x + size.x, origin.y - bearing.y + size.y, 1, 1,

		//	origin.x + bearing.x + size.x, origin.y - bearing.y + size.y, 1, 1,
		//	origin.x + bearing.x, origin.y - bearing.y + size.y, 0, 1,
		//	origin.x + bearing.x, origin.y - bearing.y, 0, 0
		//};

		////glBindVertexArray(VAO);
		////glBindBuffer(GL_ARRAY_BUFFER, VBO);
		////glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(data), data);

		//int id = 2;
		//material->getShader()->setInt(id, "textures[1].pastTexture");
		//font->glyphTextures[glyphTexId].second->select(id);

		////glDrawArrays(GL_TRIANGLES, 0, 6);	
	}
	*/

	/*
	Text::Glyph* Text::getGlyph(u16 ch){
		Glyph *glyph = nullptr;

		for(Glyph &g : characters)
			if(g.ch == ch)
				glyph = &g;

		return glyph;
	}
	 */
}