#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <stdbool.h>
#include <SDL.h>

#define true 1
#define false 0

#define iWINDOWSIZE_X 1280
#define iWINDOWSIZE_Y 720
#define iWORLDSIZE_X 26
#define iWORLDSIZE_Y 15
#define iBLOCKSIZE 50.0f

#define iCOLLOFFSET_X 0
#define iCOLLOFFSET_Y iBLOCKSIZE

#define iSIDESCOLLOFFSET 2

#define iMOVEMENTSPEED 1.5
#define iJUMPFORHOWLONG 120

Uint32 red, green, blue, white;
SDL_Surface *window = NULL;

int world[iWORLDSIZE_Y][iWORLDSIZE_X] = {{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
										{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
										{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
										{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
										{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
										{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
										{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0},
										{0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0},
										{1,1,1,1,1,1,1,1,0,0,0,1,0,0,0,0,1,0,0,0,0,0,1,1,1,1},
										{1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,1,1,0,0,0,1,1,1,1,1},
										{1,2,1,1,2,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1,1},
										{1,2,2,2,2,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1},
										{1,1,2,2,2,1,1,1,1,2,2,2,2,1,1,1,1,1,1,1,1,2,2,1,1,1},
										{1,1,1,1,1,1,1,1,1,1,2,2,2,1,1,1,1,1,1,1,1,2,2,2,1,1},
										{1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,2,1,1,1}};

int up = false;
int down = false;
int left = false;
int right = false;

int getBlockType(int xPos, int yPos) {
	return world[yPos][xPos];
}

void setBlock(int xPos, int yPos, int type) {
	world[yPos][xPos] = type;
}

// return : up, down, left, right
int* check4Collisions(int x, int y) {
    static int coll[4] = {0, 0, 0, 0};
    int rawColl[4] = {0, 0, 0, 0};

	int playerPosRounded_x = (x + iCOLLOFFSET_X) / iBLOCKSIZE;
	int playerPosRounded_y = (y + iCOLLOFFSET_Y) / iBLOCKSIZE;
	float playerPos_x = (x + iCOLLOFFSET_X) / iBLOCKSIZE;
	float playerPos_y = (y + iCOLLOFFSET_Y) / iBLOCKSIZE;

    // the player is aligned with the grid
    if(playerPosRounded_x == playerPos_x && playerPosRounded_y == playerPos_y) {
		printf("x y\n");
        rawColl[0] = (getBlockType(playerPosRounded_x-1,playerPosRounded_y-1) != 0);
        rawColl[1] = (getBlockType(playerPosRounded_x+1,playerPosRounded_y-1) != 0);
        rawColl[2] = (getBlockType(playerPosRounded_x,playerPosRounded_y) != 0);
        rawColl[3] = (getBlockType(playerPosRounded_x,playerPosRounded_y-2) != 0);
    } else if(playerPosRounded_x != playerPos_x && playerPosRounded_y == playerPos_y) {
        rawColl[0] = (getBlockType(playerPosRounded_x-1,playerPosRounded_y-1) != 0);
        rawColl[1] = (getBlockType(playerPosRounded_x+2,playerPosRounded_y-1) != 0);
        rawColl[2] = (getBlockType(playerPosRounded_x,playerPosRounded_y) != 0 || getBlockType(playerPosRounded_x+1,playerPosRounded_y) != 0);
        rawColl[3] = (getBlockType(playerPosRounded_x,playerPosRounded_y-2) != 0 || getBlockType(playerPosRounded_x+1,playerPosRounded_y-2) != 0);
    } else if(playerPosRounded_x == playerPos_x && playerPosRounded_y != playerPos_y) {
        rawColl[0] = (getBlockType(playerPosRounded_x-1,playerPosRounded_y-1) != 0 || getBlockType(playerPosRounded_x-1,playerPosRounded_y) != 0);
        rawColl[1] = (getBlockType(playerPosRounded_x+1,playerPosRounded_y-1) != 0 || getBlockType(playerPosRounded_x+1,playerPosRounded_y) != 0);
        rawColl[2] = (getBlockType(playerPosRounded_x,playerPosRounded_y+1) != 0);
        rawColl[3] = (getBlockType(playerPosRounded_x,playerPosRounded_y-2) != 0);
    } else if(playerPosRounded_x != playerPos_x && playerPosRounded_y != playerPos_y) {
        coll[0] = (getBlockType(playerPosRounded_x-1,playerPosRounded_y-1) != 0 || getBlockType(playerPosRounded_x-1,playerPosRounded_y) != 0);
        coll[1] = (getBlockType(playerPosRounded_x+2,playerPosRounded_y-1) != 0 || getBlockType(playerPosRounded_x+2,playerPosRounded_y) != 0);
		coll[2] = (getBlockType(playerPosRounded_x,playerPosRounded_y+1) != 0 || getBlockType(playerPosRounded_x+1,playerPosRounded_y+1) != 0);
        coll[3] = (getBlockType(playerPosRounded_x,playerPosRounded_y-2) != 0 || getBlockType(playerPosRounded_x+1,playerPosRounded_y-2) != 0);
    }

   	coll[0] = (rawColl[0] && x-(playerPosRounded_x)*iBLOCKSIZE < iSIDESCOLLOFFSET && playerPosRounded_y == playerPos_y || rawColl[0] && playerPosRounded_y != playerPos_y && getBlockType(playerPosRounded_x-1,playerPosRounded_y) != 0);
   	coll[1] = (rawColl[1] && ((playerPosRounded_x+1)*iBLOCKSIZE) - x < iSIDESCOLLOFFSET && playerPosRounded_y == playerPos_y || rawColl[1] && playerPosRounded_y != playerPos_y && getBlockType(playerPosRounded_x+1,playerPosRounded_y) != 0);
	coll[2] = (rawColl[2] && y-(playerPosRounded_y)*iBLOCKSIZE < iSIDESCOLLOFFSET);
   	coll[3] = (rawColl[3] && ((playerPosRounded_y-1)*iBLOCKSIZE) - y < iSIDESCOLLOFFSET);

	return coll;
}

int main(int argc, char *argv[]) {
	SDL_Init(SDL_INIT_VIDEO);
	window = SDL_SetVideoMode(iWINDOWSIZE_X, iWINDOWSIZE_Y, 32, SDL_HWSURFACE);

	white = SDL_MapRGB(window -> format, 255, 255, 255);
	red = SDL_MapRGB(window -> format, 255, 0, 0);
	green = SDL_MapRGB(window -> format, 0, 255, 0);
	blue = SDL_MapRGB(window -> format, 0, 0, 255);

	SDL_FillRect(window, NULL, white);

	SDL_Surface *player;
	player = SDL_CreateRGBSurface(SDL_HWSURFACE, iBLOCKSIZE, iBLOCKSIZE, 32, 0, 0, 0, 0);
	SDL_FillRect(player, NULL, green);

	SDL_Rect playerPos;
	playerPos.x = 400;
	playerPos.y = 50;

	SDL_BlitSurface(player, NULL, window, &playerPos);

	int yVel = 0;
	int mouseX;
	int mouseY;
	int counter = 0;

	SDL_Flip(window);

	// main loop
	while(1) {
		SDL_Event event;
		int *colls = check4Collisions(playerPos.x, playerPos.y);

		while(SDL_PollEvent(&event)) {
			if(event.type == SDL_QUIT) {
				SDL_FreeSurface(window);
				SDL_Quit();
				return 0;
				break;
			}
			else if(event.type == SDL_KEYDOWN) {
				switch(event.key.keysym.sym) {
					case SDLK_ESCAPE :
						SDL_FreeSurface(window);
						SDL_Quit();
						return 0;
						break;
					case SDLK_RIGHT :
						right = true;
						break;
					case SDLK_LEFT :
						left = true;
						break;
					case SDLK_SPACE :
						if(counter <= iJUMPFORHOWLONG && *(colls+2)) up = true;
						break;
				}
			} else if(event.type == SDL_KEYUP) {
				switch(event.key.keysym.sym) {
					case SDLK_RIGHT :
						right = false;
						break;
					case SDLK_LEFT :
						left = false;
						break;
					case SDLK_SPACE :
						counter = iJUMPFORHOWLONG;
						break;
				}
			} else if(event.type == SDL_MOUSEBUTTONDOWN) {
				int mouseX_normalised = event.button.x / iBLOCKSIZE;
				int mouseY_normalised = event.button.y / iBLOCKSIZE;
				printf("x: %i\n", mouseX_normalised);
				printf("y: %i\n", mouseY_normalised);
				printf("\n");

				switch(event.button.button) {
					case SDL_BUTTON_LEFT :
						setBlock(mouseY_normalised, mouseX_normalised, 1);
						break;
					case SDL_BUTTON_RIGHT :
						setBlock(mouseY_normalised, mouseX_normalised, 0);
						break;
				}

				drawWorld(world, playerPos);
				SDL_Flip(window);
			}
		}

		if(counter <= iJUMPFORHOWLONG && !*(colls+3) && up == true) {
			counter++;
		} else if(*(colls+3)) {
			printf("Ceiling\n");
			up = false;
			counter = iJUMPFORHOWLONG;
		} else {
			counter = 0;
			up = false;
		}

		// Is there a block underneath the player ?
		// Check 4 y collisions
		if(!*(colls+2) && up == false) {
			yVel = iMOVEMENTSPEED;
		} else if(!*(colls+3) && up == true){
			yVel = -iMOVEMENTSPEED;
		} else {
			yVel = 0;
			counter = 0;
		}

		if(yVel != 0 || up == true || down == true || left == true || right == true) {
			SDL_FreeSurface(window);
			drawWorld(world, playerPos);

			if(!*(check4Collisions(playerPos.x+iMOVEMENTSPEED+iSIDESCOLLOFFSET, playerPos.y)+1) && right == true && getBlockType(floor((playerPos.x+iSIDESCOLLOFFSET+iBLOCKSIZE+iMOVEMENTSPEED)/iBLOCKSIZE),floor(playerPos.y/iBLOCKSIZE)) == 0) {
				if(yVel == 0 && getBlockType(floor((playerPos.x+iSIDESCOLLOFFSET+iBLOCKSIZE+iMOVEMENTSPEED)/iBLOCKSIZE),floor(playerPos.y/iBLOCKSIZE)) == 0 || getBlockType(floor((playerPos.x+iBLOCKSIZE+iMOVEMENTSPEED)/iBLOCKSIZE),floor((playerPos.y+iBLOCKSIZE)/iBLOCKSIZE)) == 0 || yVel != -1 && getBlockType(floor((playerPos.x+iMOVEMENTSPEED)/iBLOCKSIZE),floor(playerPos.y/iBLOCKSIZE)) == 0) playerPos.x += iMOVEMENTSPEED;
			}

			if(!*(check4Collisions(playerPos.x-iMOVEMENTSPEED, playerPos.y)+0) && left == true && getBlockType(floor((playerPos.x-iSIDESCOLLOFFSET-iMOVEMENTSPEED)/iBLOCKSIZE),floor(playerPos.y/iBLOCKSIZE)) == 0) {
				if(yVel == 0 || getBlockType(floor((playerPos.x-iMOVEMENTSPEED)/iBLOCKSIZE),floor((playerPos.y+iBLOCKSIZE)/iBLOCKSIZE)) == 0 && yVel != 0) playerPos.x -= iMOVEMENTSPEED;
			}

			playerPos.y += yVel;

			SDL_FillRect(player, NULL, green);
			SDL_BlitSurface(player, NULL, window, &playerPos);

			SDL_BlitSurface(player, NULL, window, &playerPos);
			SDL_Flip(window);
		}
	}

	SDL_FreeSurface(window);
	SDL_Quit();
	return 0;
}

void drawWorld(int map[iWORLDSIZE_Y][iWORLDSIZE_X], SDL_Rect playerPos) {
	SDL_FillRect(window, NULL, white);
	for(int y = 0; y <= iWORLDSIZE_Y-1; y++) {
		for(int x = 0; x <= iWORLDSIZE_X-1; x++) {
			if(map[y][x] != 0) {
				SDL_Surface *dirt;
				dirt = SDL_CreateRGBSurface(SDL_HWSURFACE, iBLOCKSIZE, iBLOCKSIZE, 32, 0, 0, 0, 0);
				if(map[y][x] == 1) SDL_FillRect(dirt, NULL, blue);
				if(map[y][x] == 2) SDL_FillRect(dirt, NULL, red);
				SDL_Rect dirtPos;
				dirtPos.x = x*50;
				dirtPos.y = y*50;
				SDL_BlitSurface(dirt, NULL, window, &dirtPos);

				SDL_FreeSurface(dirt);
			}
		}
	}
}