/*
  * E-UAE - The portable Amiga Emulator
  *
  * make_hdf_wii modification of make_hdf
  *
  * A quick hack to generate a hard file image and associated config option.
  * Anybody want to show this rubbish some love, feel free.
  *
  * Copyright Richard Drummond 2007
  * Copyright Fabio Olimpieri 2014
  *
  */

#include "sysconfig.h"
#include "sysdeps.h"
#include "writelog.h"
#include <ctype.h>



static int create_hdf (const char *path, off_t size)
{
    FILE *f;
    void *buf;
    const size_t CHUNK_SIZE = 4096;

    f = fopen (path, "wb+");

    if (f) {
	if (size == 0) {
	    fclose (f);
	    return 0;
	}

	/*
	 * Try it the easy way.
	 */
	if (fseeko (f, size - 1, SEEK_SET) == 0) {
	    fputc (0, f);
	    if (fseeko (f, 0, SEEK_SET) == 0) {
		fclose (f);
		return 0;
	    }
	}

	/*
	 * Okay. That failed. Let's assume seeking passed
	 * the end of a file ain't supported. Do it the
	 * hard way.
	 */
	fseeko (f, 0, SEEK_SET);
	buf = calloc (1, CHUNK_SIZE);

	while (size >= (off_t) CHUNK_SIZE) {
	    if (fwrite (buf, CHUNK_SIZE, 1, f) != 1)
		break;
	    size -= CHUNK_SIZE;
	}

	if (size < (off_t) CHUNK_SIZE) {
	    if (size == 0 || fwrite (buf, (size_t)size, 1, f) == 1) {
		fclose (f);
		return 0;
	    }
	}
    }

    write_log ("Failed creating hdf\n");

    if (f) {
	fclose (f);
	/* TODO: Should probably delete failed image here. */
    }

    return -1;
}

int make_hdf(unsigned int size, const char *hdf_path, int blocks_per_track, int surfaces, int block_size)
{
    char *size_spec;
	const char *device_name ="DH0";
	
    uae_u64 num_blocks;
    int cylinders;
 

    if (size <= 0) {
	write_log ("Invalid size\n");
	exit (EXIT_FAILURE);
    }

    if ((size >= (1u << 31)) && (sizeof (off_t) < sizeof (uae_u64))) {
	write_log ("Specified size too large (2GB file size is maximum).\n");
	exit (EXIT_FAILURE);
    }

	
	
	if (block_size==0)  block_size = 512;
    num_blocks = size / block_size;

    /* We don't want more than (2^32)-1 blocks */
    if (num_blocks >= (1LL << 32)) {
	write_log ("Specified size too large (too many blocks).\n");
	exit (EXIT_FAILURE);
    }

    /*
     * Try and work out some plausible geometry
     *
     * We try and set surfaces and blocks_per_track to keep
     * cylinders < 65536. Prior to OS 3.9, FFS had problems with
     * more cylinders than that.
     */

    /* The default practice in UAE hardfiles, so let's start there. */
    if (blocks_per_track==0)  blocks_per_track = 32;
    if (surfaces==0) surfaces = 1;

    cylinders = num_blocks / (blocks_per_track * surfaces);

    if (cylinders == 0) {
	write_log ("Specified size is too small.\n");
	exit (EXIT_FAILURE);
    }

    while (cylinders > 65535 && surfaces < 255) {
	surfaces++;
	cylinders = num_blocks / (blocks_per_track * surfaces);
    }

    while (cylinders > 65535 && blocks_per_track < 255) {
	blocks_per_track++;
	cylinders = num_blocks / (blocks_per_track * surfaces);
    }

    /* Calculate size based on above geometry */
    num_blocks = (uae_u64)cylinders * surfaces * blocks_per_track;

    /* make file */
    if (create_hdf (hdf_path, num_blocks * block_size) < 0)
	return EXIT_FAILURE;

    /* output_spec */
    write_log ("hardfile2=rw,%s:%s,%d,%d,%d,%d,%d,\n", device_name, hdf_path, blocks_per_track, surfaces, 2, block_size, 0);
    write_log ("hardfile=rw,%d,%d,%d,%d,%s\n", blocks_per_track, surfaces, 2, block_size, hdf_path);

    return EXIT_SUCCESS;
}