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

#include "../include.h"
#include "common.h"

int (*file_ext(char *file))(struct blob *, struct userdata *) {
	size_t len = strlen(file);
	#define ext(extension) memcmp(file + len - sizeof (extension) + 1, extension, sizeof (extension))
	if ((ext(".mptm") && ext(".mod") && ext(".MOD") && ext(".xm") && ext(".s3m") && ext(".it")) == 0) {
		return module_openmpt;
	} else if ((ext(".mid") && ext(".MID") && ext(".midi")) == 0) {
		return module_fluidsynth;
	}
	#undef ext
	return NULL;
}

struct blob load_file(char const *const name) {
	const size_t START_SIZE = 8192;
	FILE *file = fopen(name, "rb");
	if (file == NULL) {
		return (struct blob) {.data = NULL};
	}
	void *data = malloc(START_SIZE);
	size_t allocated = START_SIZE;
	size_t used = 0;
	while (1) {
		size_t read = fread(data + used, 1, allocated - used, file);
		if (read != allocated - used) {
			used += read;
			break;
		}
		used += read;
		allocated *= 2;
		void *const newdata = realloc(data, allocated);
		if (newdata == NULL) {
			goto realloc_error;
		}
		data = newdata;
	}
	void *const newdata = realloc(data, used);
	if (newdata == NULL && used != 0) {
		goto realloc_error;
	}
	fclose(file);
	return (struct blob) {.data = newdata, .size = used};
	
	realloc_error:
	free(data);
	fclose(file);
	return (struct blob) {.data = NULL};
}