/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   texture.c                                          :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: charles <charles.cabergs@gmail.com>        +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2020/05/11 14:27:34 by charles           #+#    #+#             */
/*   Updated: 2020/05/13 17:11:06 by charles          ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "scop.h"

typedef struct __attribute__((__packed__))
{
	uint8_t		signature[2];
	uint32_t	file_size;
	uint32_t	reserved;
	uint32_t	img_data_offset;
}				t_bmp_file_header;

typedef struct __attribute__((__packed__))
{
	uint32_t	header_size;
	uint32_t	width;
	uint32_t	height;
	uint16_t	color_planes;
	uint16_t	depth;
	uint32_t	compression;
	uint32_t	image_size;
	uint32_t	horizontal_res;
	uint32_t	vertical_res;
	uint32_t	color_table_len;
	uint32_t	color_count;
}				t_bmp_info_header;

uint8_t			*st_read_bmp(char *filepath, size_t *width, size_t *height)
{
	uint8_t				*data;
	t_bmp_file_header	file_header;
	t_bmp_info_header	info_header;
	int	fd;

	fd = open(filepath, O_RDONLY);
	read(fd, &file_header, sizeof(t_bmp_file_header));
	if (file_header.signature[0] != 'B' || file_header.signature[1] != 'M')
	{
		close(fd);
		return (NULL);
	}
	read(fd, &info_header, sizeof(t_bmp_info_header));
	if ((data = malloc(info_header.image_size)) == NULL)
	{
		close(fd);
		return (NULL);
	}
	*width = info_header.width;
	*height = info_header.height;
	read(fd, data, info_header.image_size);  // padding
	close(fd);
	return (data);
}

unsigned int	texture_new(char *filepath)
{
	uint8_t			*data;
	unsigned int	texture;
	size_t			width;
	size_t			height;

	if ((data = st_read_bmp(filepath, &width, &height)) == NULL)
		return (0);
	GL_CALL(glGenTextures(1, &texture));
	GL_CALL(glBindTexture(GL_TEXTURE_2D, texture));
	GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR));
	GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR));
	GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE));
	GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE));
	GL_CALL(glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data));
	/* glBindTexture(GL_TEXTURE_2D, 0); */
	free(data);
	return (texture);
}