#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "backend.h"
#include "defines.h"
#include "config.h"

#if SETTINGS_UEBERZUG_IMAGE_PREVIEW != 0
static FILE *ueberzug = NULL;
#endif
extern unsigned int terminal_height;
extern unsigned int terminal_width;
char previewd;

char* text(char *path, unsigned long *file_size);
void images_print(char *file_name);
void images_clear();
char* generic(char *path);

char* get_mimetype(char *path){
	static char *cmd_str = "file --mime-type -b ./\"";
	unsigned long cmd_len = strlen(cmd_str);
	unsigned int path_len = strlen(path);

	char *cmd = malloc((cmd_len + path_len) + 2);
	memset(cmd, ' ', cmd_len + path_len);
	memcpy(cmd, cmd_str, cmd_len);
	memcpy(cmd + cmd_len, path, path_len);
	cmd[cmd_len + path_len] = '\"';
	cmd[cmd_len + path_len + 1] = '\0';

	FILE *cmd_open = popen(cmd, "r");
	char *line = NULL;
	size_t size = 0;
	if (getline(&line, &size, cmd_open) != -1){
		pclose(cmd_open);
		return line;
	} else {
		pclose(cmd_open);
		return "unknown";
	}
}
char* preview_file(char *file_name, unsigned long file_size){ 
	/* this calls "file" on path */

	char *file_buffer;


	char *mime = get_mimetype(file_name);

	#if SETTINGS_UEBERZUG_IMAGE_PREVIEW != 0
	images_clear();
	#endif

	if (strstr(mime, "text")) {
		file_buffer = text(file_name, &file_size);
	#if SETTINGS_UEBERZUG_IMAGE_PREVIEW != 0
	} else if (strstr(mime, "image")) {
		file_buffer = generic(file_name);
		images_print(file_name);
		previewd = 1;
	#endif
	} else  {
		file_buffer = generic(file_name);
	}

	free(mime);
	return file_buffer;

}
char* text(char *path, unsigned long *file_size){

	unsigned long size = (terminal_width/2) * terminal_height;
	if (size > *file_size) {
		size = *file_size;
	}
	char *file_buffer = malloc(size + 1);
	FILE *fp = fopen(path, "r");
	if (fread(file_buffer, size, 1, fp) != 0) {
		file_buffer[size] = '\0';
		return file_buffer;
	} else {
		return "failed reading file";
	}
}
char* generic(char *path){
	char *cmd = concat("file ./\"", path);
	cmd = concat(cmd, "\"");

	FILE *cmd_open = popen(cmd, "r");
	char *line = NULL;
	size_t size = 0;
	if (getline(&line, &size, cmd_open) != -1) {
		pclose(cmd_open);
		return line;
	} else {
		pclose(cmd_open);
		return "failed executing shell command \"file\"";
	}
}
#if SETTINGS_UEBERZUG_IMAGE_PREVIEW != 0
void images_clear() {
	if (previewd == 1) {
		fprintf(ueberzug, "{\"action\": \"remove\",  \
				\"identifier\": \"preview\"}\n");
		fflush(ueberzug);
		previewd = 0;
	}
}
void images_print(char *file_name) {
	char *path=getcwd(NULL, 0);

	fprintf(ueberzug, "{\"action\":\"add\", \
			\"identifier\":\"preview\", \
			\"max_height\":%d, \
			\"max_width\":%d, \
			\"y\":0, \
			\"x\":%d, \
			\"path\":\"%s/%s\"}\n", terminal_height, terminal_width/2, terminal_width/2, path, file_name);
	fflush(ueberzug);
	free(path);
}
void ueberzug_init(){

	#if SETTINGS_UEBERZUG_IMAGE_PREVIEW == 2
	ueberzug = popen("ueberzug layer -s ", "w");
	#elif SETTINGS_UEBERZUG_IMAGE_PREVIEW == 1
	ueberzug = popen("ueberzug layer -s --no-cache ", "w");
	#endif
}
#endif