/* ----------------------------------------------------------------------- *
 *
 *   Copyright 2003 Lars Munch Christensen - All Rights Reserved
 *   Copyright 1998-2008 H. Peter Anvin - All Rights Reserved
 *   Copyright 2012-2014 Pete Batard
 *
 *   Based on the Linux installer program for SYSLINUX by H. Peter Anvin
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
 *   Boston MA 02111-1307, USA; either version 2 of the License, or
 *   (at your option) any later version; incorporated herein by reference.
 *
 * ----------------------------------------------------------------------- */

/* Memory leaks detection - define _CRTDBG_MAP_ALLOC as preprocessor macro */
#ifdef _CRTDBG_MAP_ALLOC
#include <stdlib.h>
#include <crtdbg.h>
#endif

#include <windows.h>
#include <windowsx.h>
#include <stdio.h>
#include <malloc.h>
#include <ctype.h>

#include "rufus.h"
#include "drive.h"
#include "resource.h"
#include "localization.h"
#include "msapi_utf8.h"

#include "syslinux.h"
#include "syslxfs.h"
#include "libfat.h"
#include "setadv.h"

unsigned char* syslinux_ldlinux[2] = { NULL, NULL };
DWORD syslinux_ldlinux_len[2];
unsigned char* syslinux_mboot = NULL;
DWORD syslinux_mboot_len;

/*
 * Wrapper for ReadFile suitable for libfat
 */
int libfat_readfile(intptr_t pp, void *buf, size_t secsize,
		    libfat_sector_t sector)
{
	uint64_t offset = (uint64_t) sector * secsize;
	LONG loword = (LONG) offset;
	LONG hiword = (LONG) (offset >> 32);
	LONG hiwordx = hiword;
	DWORD bytes_read;

	if (SetFilePointer((HANDLE) pp, loword, &hiwordx, FILE_BEGIN) != loword ||
		hiword != hiwordx ||
		!ReadFile((HANDLE) pp, buf, (DWORD)secsize, &bytes_read, NULL) ||
		bytes_read != secsize) {
		uprintf("Cannot read sector %u\n", sector);
		return 0;
	}

	return (int)secsize;
}

/*
 * Extract the ldlinux.sys and ldlinux.bss from resources,
 * then patch and install them
 */
BOOL InstallSyslinux(DWORD drive_index, char drive_letter)
{
	HANDLE f_handle = INVALID_HANDLE_VALUE;
	HANDLE d_handle = INVALID_HANDLE_VALUE;
	DWORD bytes_read;
	DWORD bytes_written;
	BOOL r = FALSE;
	FILE* fd;
	size_t len;

	static unsigned char sectbuf[SECTOR_SIZE];
	static char* resource[2][2] = {
		{ MAKEINTRESOURCEA(IDR_SL_LDLINUX_V4_SYS), MAKEINTRESOURCEA(IDR_SL_LDLINUX_V4_BSS) },
		{ MAKEINTRESOURCEA(IDR_SL_LDLINUX_V5_SYS), MAKEINTRESOURCEA(IDR_SL_LDLINUX_V5_BSS) } };
	const char* ldlinux = "ldlinux";
	const char* syslinux = "syslinux";
	const char* ldlinux_ext[3] = { "sys", "bss", "c32" };
	const char* mboot_c32 = "mboot.c32";
	char path[MAX_PATH], tmp[64];
	struct libfat_filesystem *fs;
	libfat_sector_t s, *secp;
	libfat_sector_t *sectors = NULL;
	int ldlinux_sectors;
	uint32_t ldlinux_cluster;
	int i, nsectors;
	int dt = (int)ComboBox_GetItemData(hBootType, ComboBox_GetCurSel(hBootType));
	BOOL use_v5 = (dt == DT_SYSLINUX_V5) || ((dt == DT_ISO) && (SL_MAJOR(iso_report.sl_version) >= 5));

	PrintStatus(0, TRUE, MSG_234, (dt == DT_ISO)?iso_report.sl_version_str:embedded_sl_version_str[use_v5?1:0]);

	/* Initialize the ADV -- this should be smarter */
	syslinux_reset_adv(syslinux_adv);

	/* Access a copy of the ldlinux.sys & ldlinux.bss resources (downloaded or embedded) */
	if ((syslinux_ldlinux_len[0] != 0) && (syslinux_ldlinux_len[1] != 0)) {
		IGNORE_RETVAL(_chdirU(app_dir));
		for (i=0; i<2; i++) {
			syslinux_ldlinux[i] = (unsigned char*) malloc(syslinux_ldlinux_len[i]);
			if (syslinux_ldlinux[i] == NULL)
				goto out;
			static_sprintf(path, "%s/%s-%s/%s.%s", FILES_DIR, syslinux, iso_report.sl_version_str, ldlinux, i==0?"sys":"bss");
			fd = fopen(path, "rb");
			if (fd == NULL) {
				uprintf("Could not open %s\n", path);
				goto out;
			}
			len = fread(syslinux_ldlinux[i], 1, (size_t)syslinux_ldlinux_len[i], fd);
			fclose(fd);
			if (len != (size_t)syslinux_ldlinux_len[i]) {
				uprintf("Could not read %s\n", path);
				goto out;
			}
			uprintf("Using existing './%s'\n", path);
		}
	} else {
		for (i=0; i<2; i++) {
		static_sprintf(tmp, "%s.%s", ldlinux, ldlinux_ext[i]);
		syslinux_ldlinux[i] = GetResource(hMainInstance, resource[use_v5?1:0][i],
			_RT_RCDATA, tmp, &syslinux_ldlinux_len[i], TRUE);
		if (syslinux_ldlinux[i] == NULL)
			goto out;
		}
	}

	/* Create ldlinux.sys file */
	static_sprintf(path, "%C:\\%s.%s", drive_letter, ldlinux, ldlinux_ext[0]);
	f_handle = CreateFileA(path, GENERIC_READ | GENERIC_WRITE,
			  FILE_SHARE_READ | FILE_SHARE_WRITE,
			  NULL, CREATE_ALWAYS,
			  FILE_ATTRIBUTE_READONLY | FILE_ATTRIBUTE_SYSTEM |
			  FILE_ATTRIBUTE_HIDDEN, NULL);

	if (f_handle == INVALID_HANDLE_VALUE) {
		uprintf("Unable to create '%s'\n", &path[3]);
		goto out;
	}

	/* Write ldlinux.sys file */
	if (!WriteFile(f_handle, syslinux_ldlinux[0], syslinux_ldlinux_len[0],
		   &bytes_written, NULL) ||
		bytes_written != syslinux_ldlinux_len[0]) {
		uprintf("Could not write '%s'\n", &path[3]);
		goto out;
	}
	if (!WriteFile(f_handle, syslinux_adv, 2 * ADV_SIZE,
		   &bytes_written, NULL) ||
		bytes_written != 2 * ADV_SIZE) {
		uprintf("Could not write ADV to '%s'\n", &path[3]);
		goto out;
	}

	uprintf("Successfully wrote '%s'\n", &path[3]);
	if (dt != DT_ISO)
		UpdateProgress(OP_DOS, -1.0f);

	/* Now flush the media */
	if (!FlushFileBuffers(f_handle)) {
		uprintf("FlushFileBuffers failed\n");
		goto out;
	}

	/* Reopen the volume (we already have a lock) */
	d_handle = GetLogicalHandle(drive_index, TRUE, FALSE);
	if (d_handle == INVALID_HANDLE_VALUE) {
		uprintf("Could open volume for Syslinux installation\n");
		goto out;
	}

	/* Map the file (is there a better way to do this?) */
	ldlinux_sectors = (syslinux_ldlinux_len[0] + 2 * ADV_SIZE + SECTOR_SIZE - 1) >> SECTOR_SHIFT;
	sectors = (libfat_sector_t*) calloc(ldlinux_sectors, sizeof *sectors);
	if (sectors == NULL)
		goto out;
	fs = libfat_open(libfat_readfile, (intptr_t) d_handle);
	if (fs == NULL) {
		uprintf("Syslinux FAT access error\n");
		goto out;
	}
	ldlinux_cluster = libfat_searchdir(fs, 0, "LDLINUX SYS", NULL);
	secp = sectors;
	nsectors = 0;
	s = libfat_clustertosector(fs, ldlinux_cluster);
	while (s && nsectors < ldlinux_sectors) {
		*secp++ = s;
		nsectors++;
		s = libfat_nextsector(fs, s);
	}
	libfat_close(fs);

	/* Patch ldlinux.sys and the boot sector */
	syslinux_patch(sectors, nsectors, 0, 0, NULL, NULL);

	/* Rewrite the file */
	if (SetFilePointer(f_handle, 0, NULL, FILE_BEGIN) != 0 ||
		!WriteFile(f_handle, syslinux_ldlinux[0], syslinux_ldlinux_len[0],
			   &bytes_written, NULL)
		|| bytes_written != syslinux_ldlinux_len[0]) {
		uprintf("Could not write '%s': %s\n", &path[3], WindowsErrorString());
		goto out;
	}

	/* Close file */
	safe_closehandle(f_handle);

	/* Read existing FAT data into boot sector */
	if (SetFilePointer(d_handle, 0, NULL, FILE_BEGIN) != 0 ||
		!ReadFile(d_handle, sectbuf, SECTOR_SIZE,
			   &bytes_read, NULL)
		|| bytes_read != SECTOR_SIZE) {
		uprintf("Could not read boot record: %s\n", WindowsErrorString());
		goto out;
	}

	/* Make the syslinux boot sector */
	syslinux_make_bootsect(sectbuf, VFAT);

	/* Write boot sector back */
	if (SetFilePointer(d_handle, 0, NULL, FILE_BEGIN) != 0 ||
		!WriteFile(d_handle, sectbuf, SECTOR_SIZE,
			   &bytes_written, NULL)
		|| bytes_written != SECTOR_SIZE) {
		uprintf("Could not write Syslinux boot record: %s\n", WindowsErrorString());
		goto out;
	}

	uprintf("Successfully wrote Syslinux boot record\n");

	if (dt == DT_SYSLINUX_V5) {
		IGNORE_RETVAL(_chdirU(app_dir));
		static_sprintf(path, "%s/%s-%s", FILES_DIR, syslinux, embedded_sl_version_str[1]);
		IGNORE_RETVAL(_chdir(path));
		static_sprintf(path, "%C:\\%s.%s", drive_letter, ldlinux, ldlinux_ext[2]);
		fd = fopen(&path[3], "rb");
		if (fd == NULL) {
			uprintf("Caution: No '%s' was provided. The target will be missing a required Syslinux file!\n", &path[3]);
		} else {
			fclose(fd);
			if (CopyFileA(&path[3], path, TRUE)) {
				uprintf("Created '%s' (from '%s/%s-%s/%s')", path, FILES_DIR, syslinux, embedded_sl_version_str[1], &path[3]);
			} else {
				uprintf("Failed to create '%s': %s\n", path, WindowsErrorString());
			}
		}
	} else if (IS_REACTOS(iso_report)) {
		uprintf("Setting up ReactOS...\n");
		syslinux_mboot = GetResource(hMainInstance, MAKEINTRESOURCEA(IDR_SL_MBOOT_C32),
			_RT_RCDATA, "mboot.c32", &syslinux_mboot_len, FALSE);
		if (syslinux_mboot == NULL) {
			goto out;
		}
		/* Create mboot.c32 file */
		static_sprintf(path, "%C:\\%s", drive_letter, mboot_c32);
		f_handle = CreateFileA(path, GENERIC_READ | GENERIC_WRITE,
				  FILE_SHARE_READ | FILE_SHARE_WRITE,
				  NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
		if (f_handle == INVALID_HANDLE_VALUE) {
			uprintf("Unable to create '%s'\n", path);
			goto out;
		}
		if (!WriteFile(f_handle, syslinux_mboot, syslinux_mboot_len,
			   &bytes_written, NULL) ||
			bytes_written != syslinux_mboot_len) {
			uprintf("Could not write '%s'\n", path);
			goto out;
		}
		safe_closehandle(f_handle);
		static_sprintf(path, "%C:\\syslinux.cfg", drive_letter);
		fd = fopen(path, "w");
		if (fd == NULL) {
			uprintf("Could not create ReactOS 'syslinux.cfg'\n");
			goto out;
		}
		/* Write the syslinux.cfg for ReactOS */
		fprintf(fd, "DEFAULT ReactOS\nLABEL ReactOS\n  KERNEL %s\n  APPEND %s\n",
			mboot_c32, iso_report.reactos_path);
		fclose(fd);
	}

	if (dt != DT_ISO)
		UpdateProgress(OP_DOS, -1.0f);

	r = TRUE;

out:
	safe_free(syslinux_ldlinux[0]);
	safe_free(syslinux_ldlinux[1]);
	safe_free(sectors);
	safe_closehandle(d_handle);
	safe_closehandle(f_handle);
	return r;
}