/*
 * Rufus: The Reliable USB Formatting Utility
 * ISO file extraction
 * Copyright (c) 2011-2012 Pete Batard <pete@akeo.ie>
 * Based on libcdio's iso & udf samples:
 * Copyright (c) 2003-2011 Rocky Bernstein <rocky@gnu.org>
 *
 * 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, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/* 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 <stdio.h>
#include <string.h>
#include <malloc.h>
#include <errno.h>
#include <direct.h>

#include <cdio/cdio.h>
#include <cdio/logging.h>
#include <cdio/iso9660.h>
#include <cdio/udf.h>

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

#ifndef MIN
#define MIN(a,b) (((a) < (b)) ? (a) : (b))
#endif
#ifndef PBS_MARQUEE
#define PBS_MARQUEE 0x08
#endif
#ifndef PBM_SETMARQUEE
#define PBM_SETMARQUEE (WM_USER+10)
#endif
// How often should we update the progress bar (in 2K blocks) as updating
// the progress bar for every block will bring extraction to a crawl
#define PROGRESS_THRESHOLD        1024
#define FOUR_GIGABYTES            4294967296LL

// Needed for UDF ISO access
CdIo_t* cdio_open (const char *psz_source, driver_id_t driver_id) {return NULL;}
void cdio_destroy (CdIo_t *p_cdio) {}

RUFUS_ISO_REPORT iso_report;
int64_t iso_blocking_status = -1;
#define ISO_BLOCKING(x) do {x; iso_blocking_status++; } while(0)
static const char *psz_extract_dir;
static const char *bootmgr_name = "bootmgr";
static const char *ldlinux_name = "ldlinux.sys";
static const char *isolinux_name[] = { "isolinux.cfg", "syslinux.cfg", "extlinux.conf"};
static uint8_t i_joliet_level = 0;
static uint64_t total_blocks, nb_blocks;
static BOOL scan_only = FALSE;
static StrArray config_path;

// TODO: Timestamp & permissions preservation

// Convert a file size to human readable
static __inline char* size_to_hr(int64_t size)
{
	int suffix = 0;
	static char str_size[24];
	const char* sizes[] = { "", "KB", "MB", "GB", "TB" };
	double hr_size = (double)size;
	while ((suffix < ARRAYSIZE(sizes)) && (hr_size >= 1024.0)) {
		hr_size /= 1024.0;
		suffix++;
	}
	if (suffix == 0) {
		safe_sprintf(str_size, sizeof(str_size), " (%d bytes)", (int)hr_size);
	} else {
		safe_sprintf(str_size, sizeof(str_size), " (%0.1f %s)", hr_size, sizes[suffix]);
	}
	return str_size;
}

static void log_handler (cdio_log_level_t level, const char *message)
{
	switch(level) {
	case CDIO_LOG_DEBUG:
		return;
	default:
		uprintf("libcdio: %s\n", message);
	}
}

/*
 * Workaround for isolinux config files requiring an ISO label for kernel
 * append that may be different from our USB label.
 * NB: this is intended as a quick-and-dirty workaround, because it is the
 * distro creator's job to make their config and labels also work with USB.
 * As such, this process may fail if:
 * - the label is on the block size limit, for cfg files of more than 2KB
 * - the user changed the label to one that is larger than the one from the cfg
 * - the cfg is weird (more than one label on the same line, etc.)
 */
static void process_config(char* buf, size_t buf_size, const char* cfg_name)
{
	char last_char, eol_char, *label;
	size_t i, j, k;

	// Don't apply workaround if USB label is the same or longer than ISO
	if ( (strcmp(iso_report.label, iso_report.usb_label) == 0)
	  || (strlen(iso_report.label) < strlen(iso_report.usb_label)) )
		return;

	// Make sure our buffer is NUL terminated
	if (buf_size >= UDF_BLOCKSIZE)	// UDF_BLOCKSIZE = ISO_BLOCKSIZE = 2048
		buf_size = UDF_BLOCKSIZE-1;
	last_char = buf[buf_size];
	buf[buf_size] = 0;

	for (i=0; i<buf_size; i++) {
		// Check if there is a line starting with "append" (case insensitive)
		if (_strnicmp(&buf[i], "append", sizeof("append")-1) == 0) {
			for (j=i; (buf[j]!=0x00)&&(buf[j]!=0x0A)&&(buf[j]!=0x0D); j++);	// EOL
			eol_char = buf[j];	// Make sure the line is NUL terminated
			buf[j] = 0;
			label = strstr(&buf[i], iso_report.label);
			if (label != NULL) {
				// Since label is longer than usb_label we can replace it
				for (k=0; k<strlen(iso_report.label); k++)
					label[k] = (k<strlen(iso_report.usb_label))?iso_report.usb_label[k]:' ';
				uprintf("  Patched config file to use USB label '%s'\n", iso_report.usb_label);
//				uprintf("  Patched line: '%s'\n", &buf[i]);
			}
			// Revert EOL
			buf[j] = eol_char;
			i = j;
		}
	}
	// Revert NUL terminator
	buf[buf_size] = last_char;
}

/*
 * Scan and set ISO properties
 * Returns true if the the current file does not need to be processed further
 */
static __inline BOOL check_iso_props(BOOL is_root, BOOL* is_syslinux_cfg, int64_t i_file_length,
	const char* psz_basename, char* psz_fullpath)
{
	size_t i;

	// Check for an isolinux/syslinux config file anywhere
	*is_syslinux_cfg = FALSE;
	for (i=0; i<ARRAYSIZE(isolinux_name); i++) {
		if (_stricmp(psz_basename, isolinux_name[i]) == 0)
			*is_syslinux_cfg = TRUE;
	}

	if (scan_only) {
		// Check for a "bootmgr" file in root (psz_path = "")
		if (is_root && (_stricmp(psz_basename, bootmgr_name) == 0))
			iso_report.has_bootmgr = TRUE;
		if (*is_syslinux_cfg) {
			iso_report.has_isolinux = TRUE;
			// Maintain a list of all the isolinux/syslinux configs identified so far
			StrArrayAdd(&config_path, psz_fullpath);
		}
		if (i_file_length >= FOUR_GIGABYTES)
			iso_report.has_4GB_file = TRUE;
		// Compute projected size needed
		total_blocks += i_file_length/UDF_BLOCKSIZE;
		// NB: ISO_BLOCKSIZE = UDF_BLOCKSIZE
		if ((i_file_length != 0) && (i_file_length%ISO_BLOCKSIZE == 0))	// 
			total_blocks++;
		return TRUE;
	}
	// In case there's an ldlinux.sys on the ISO, prevent it from overwriting ours
	if (is_root && (safe_strcmp(psz_basename, ldlinux_name) == 0)) {
		uprintf("skipping % file from ISO image\n", ldlinux_name);
		return TRUE;
	}
	return FALSE;
}

// Returns 0 on success, nonzero on error
static int udf_extract_files(udf_t *p_udf, udf_dirent_t *p_udf_dirent, const char *psz_path)
{
	HANDLE file_handle = NULL;
	DWORD buf_size, wr_size;
	BOOL r, is_syslinux_cfg;
	int i_length;
	size_t i, nul_pos;
	char* psz_fullpath = NULL;
	const char* psz_basename;
	udf_dirent_t *p_udf_dirent2;
	uint8_t buf[UDF_BLOCKSIZE];
	int64_t i_read, i_file_length;

	if ((p_udf_dirent == NULL) || (psz_path == NULL))
		return 1;

	while ((p_udf_dirent = udf_readdir(p_udf_dirent)) != NULL) {
		if (FormatStatus) goto out;
		psz_basename = udf_get_filename(p_udf_dirent);
		i_length = (int)(3 + strlen(psz_path) + strlen(psz_basename) + strlen(psz_extract_dir) + 24);
		psz_fullpath = (char*)calloc(sizeof(char), i_length);
		if (psz_fullpath == NULL) {
			uprintf("Error allocating file name\n");
			goto out;
		}
		i_length = safe_sprintf(psz_fullpath, i_length, "%s%s/%s", psz_extract_dir, psz_path, psz_basename);
		if (i_length < 0) {
			goto out;
		}
		if (udf_is_dir(p_udf_dirent)) {
			if (!scan_only) _mkdir(psz_fullpath);
			p_udf_dirent2 = udf_opendir(p_udf_dirent);
			if (p_udf_dirent2 != NULL) {
				if (udf_extract_files(p_udf, p_udf_dirent2, &psz_fullpath[strlen(psz_extract_dir)]))
					goto out;
			}
		} else {
			i_file_length = udf_get_file_length(p_udf_dirent);
			if (check_iso_props((*psz_path == 0), &is_syslinux_cfg, i_file_length, psz_basename, psz_fullpath)) {
				safe_free(psz_fullpath);
				continue;
			}
			// Replace slashes with backslashes and append the size to the path for UI display
			nul_pos = safe_strlen(psz_fullpath);
			for (i=0; i<nul_pos; i++) if (psz_fullpath[i] == '/') psz_fullpath[i] = '\\';
			safe_strcpy(&psz_fullpath[nul_pos], 24, size_to_hr(i_file_length));
			uprintf("Extracting: %s\n", psz_fullpath);
			SetWindowTextU(hISOFileName, psz_fullpath);
			// Remove the appended size for extraction
			psz_fullpath[nul_pos] = 0;
			file_handle = CreateFileU(psz_fullpath, GENERIC_READ | GENERIC_WRITE,
				FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
			if (file_handle == INVALID_HANDLE_VALUE) {
				uprintf("  Unable to create file: %s\n", WindowsErrorString());
				goto out;
			}
			while (i_file_length > 0) {
				if (FormatStatus) goto out;
				memset(buf, 0, UDF_BLOCKSIZE);
				i_read = udf_read_block(p_udf_dirent, buf, 1);
				if (i_read < 0) {
					uprintf("  Error reading UDF file %s\n", &psz_fullpath[strlen(psz_extract_dir)]);
					goto out;
				}
				buf_size = (DWORD)MIN(i_file_length, i_read);
				if (is_syslinux_cfg)
					process_config((char*)buf, (size_t)buf_size, psz_fullpath);
				ISO_BLOCKING(r = WriteFile(file_handle, buf, buf_size, &wr_size, NULL));
				if ((!r) || (buf_size != wr_size)) {
					uprintf("  Error writing file: %s\n", WindowsErrorString());
					goto out;
				}
				i_file_length -= i_read;
				if (nb_blocks++ % PROGRESS_THRESHOLD == 0) {
					SendMessage(hISOProgressBar, PBM_SETPOS, (WPARAM)((MAX_PROGRESS*nb_blocks)/total_blocks), 0);
				}
			}
			// If you have a fast USB 3.0 device, the default Windows buffering does an
			// excellent job at compensating for our small blocks read/writes to max out the
			// device's bandwidth.
			// The drawback however is with cancellation. With a large file, CloseHandle()
			// may take forever to complete and is not interruptible. We try to detect this.
			ISO_BLOCKING(safe_closehandle(file_handle));
		}
		safe_free(psz_fullpath);
	}
	return 0;

out:
	if (p_udf_dirent != NULL)
		udf_dirent_free(p_udf_dirent);
	ISO_BLOCKING(safe_closehandle(file_handle));
	safe_free(psz_fullpath);
	return 1;
}

// Returns 0 on success, nonzero on error
static int iso_extract_files(iso9660_t* p_iso, const char *psz_path)
{
	HANDLE file_handle = NULL;
	DWORD buf_size, wr_size;
	BOOL s, is_syslinux_cfg;
	int i_length, r = 1;
	char psz_fullpath[1024], *psz_basename;
	const char *psz_iso_name = &psz_fullpath[strlen(psz_extract_dir)];
	unsigned char buf[ISO_BLOCKSIZE];
	CdioListNode_t* p_entnode;
	iso9660_stat_t *p_statbuf;
	CdioList_t* p_entlist;
	size_t i, nul_pos;
	lsn_t lsn;
	int64_t i_file_length;

	if ((p_iso == NULL) || (psz_path == NULL))
		return 1;

	i_length = safe_sprintf(psz_fullpath, sizeof(psz_fullpath), "%s%s/", psz_extract_dir, psz_path);
	if (i_length < 0)
		return 1;
	psz_basename = &psz_fullpath[i_length];

	p_entlist = iso9660_ifs_readdir(p_iso, psz_path);
	if (!p_entlist) {
		uprintf("Could not access directory %s\n", psz_path);
		return 1;
	}

	_CDIO_LIST_FOREACH(p_entnode, p_entlist) {
		if (FormatStatus) goto out;
		p_statbuf = (iso9660_stat_t*) _cdio_list_node_data(p_entnode);
		/* Eliminate . and .. entries */
		if ( (strcmp(p_statbuf->filename, ".") == 0)
			|| (strcmp(p_statbuf->filename, "..") == 0) )
			continue;
		iso9660_name_translate_ext(p_statbuf->filename, psz_basename, i_joliet_level);
		if (p_statbuf->type == _STAT_DIR) {
			if (!scan_only) _mkdir(psz_fullpath);
			if (iso_extract_files(p_iso, psz_iso_name))
				goto out;
		} else {
			i_file_length = p_statbuf->size;
			if (check_iso_props((*psz_path == 0), &is_syslinux_cfg, i_file_length, psz_basename, psz_fullpath)) {
				continue;
			}
			// Replace slashes with backslashes and append the size to the path for UI display
			nul_pos = safe_strlen(psz_fullpath);
			for (i=0; i<nul_pos; i++) if (psz_fullpath[i] == '/') psz_fullpath[i] = '\\';
			safe_strcpy(&psz_fullpath[nul_pos], 24, size_to_hr(i_file_length));
			uprintf("Extracting: %s\n", psz_fullpath);
			SetWindowTextU(hISOFileName, psz_fullpath);
			// ISO9660 cannot handle backslashes
			for (i=0; i<nul_pos; i++) if (psz_fullpath[i] == '\\') psz_fullpath[i] = '/';
			psz_fullpath[nul_pos] = 0;
			file_handle = CreateFileU(psz_fullpath, GENERIC_READ | GENERIC_WRITE,
				FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
			if (file_handle == INVALID_HANDLE_VALUE) {
				uprintf("  Unable to create file: %s\n", WindowsErrorString());
				goto out;
			}
			for (i = 0; i_file_length > 0; i++) {
				if (FormatStatus) goto out;
				memset(buf, 0, ISO_BLOCKSIZE);
				lsn = p_statbuf->lsn + (lsn_t)i;
				if (iso9660_iso_seek_read(p_iso, buf, lsn, 1) != ISO_BLOCKSIZE) {
					uprintf("  Error reading ISO9660 file %s at LSN %lu\n",
						psz_iso_name, (long unsigned int)lsn);
					goto out;
				}
				buf_size = (DWORD)MIN(i_file_length, ISO_BLOCKSIZE);
				if (is_syslinux_cfg)
					process_config((char*)buf, (size_t)buf_size, psz_fullpath);
				ISO_BLOCKING(s = WriteFile(file_handle, buf, buf_size, &wr_size, NULL));
				if ((!s) || (buf_size != wr_size)) {
					uprintf("  Error writing file: %s\n", WindowsErrorString());
					goto out;
				}
				i_file_length -= ISO_BLOCKSIZE;
				if (nb_blocks++ % PROGRESS_THRESHOLD == 0) {
					SendMessage(hISOProgressBar, PBM_SETPOS, (WPARAM)((MAX_PROGRESS*nb_blocks)/total_blocks), 0);
				}
			}
			ISO_BLOCKING(safe_closehandle(file_handle));
		}
	}
	r = 0;

out:
	ISO_BLOCKING(safe_closehandle(file_handle));
	_cdio_list_free(p_entlist, true);
	return r;
}

BOOL ExtractISO(const char* src_iso, const char* dest_dir, bool scan)
{
	size_t i;
	FILE* fd;
	BOOL r = FALSE;
	iso9660_t* p_iso = NULL;
	udf_t* p_udf = NULL; 
	udf_dirent_t* p_udf_root;
	LONG progress_style;
	char* vol_id;
	char syslinux_path[64];
	const char* scan_text = "Scanning ISO image...";

	if ((src_iso == NULL) || (dest_dir == NULL))
		return FALSE;

	scan_only = scan;
	cdio_log_set_handler(log_handler);
	psz_extract_dir = dest_dir;
	progress_style = GetWindowLong(hISOProgressBar, GWL_STYLE);
	if (scan_only) {
		total_blocks = 0;
		iso_report.projected_size = 0;
		iso_report.has_4GB_file = FALSE;
		iso_report.has_bootmgr = FALSE;
		iso_report.has_isolinux = FALSE;
		// String array of all isolinux/syslinux locations
		StrArrayCreate(&config_path, 8);
		// Change the Window title and static text
		SetWindowTextU(hISOProgressDlg, scan_text);
		SetWindowTextU(hISOFileName, scan_text);
		// Change progress style to marquee for scanning
		SetWindowLong(hISOProgressBar, GWL_STYLE, progress_style | PBS_MARQUEE);
		SendMessage(hISOProgressBar, PBM_SETMARQUEE, TRUE, 0);
	} else {
		uprintf("Extracting files...\n");
		if (total_blocks == 0) {
			uprintf("Error: ISO has not been properly scanned.\n");
			FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|APPERR(ERROR_ISO_SCAN);
			goto out;
		}
		nb_blocks = 0;
		iso_blocking_status = 0;
		SetWindowLong(hISOProgressBar, GWL_STYLE, progress_style & (~PBS_MARQUEE));
		SendMessage(hISOProgressBar, PBM_SETPOS, 0, 0);
	}
	ShowWindow(hISOProgressDlg, SW_SHOW);
	UpdateWindow(hISOProgressDlg);

	/* First try to open as UDF - fallback to ISO if it failed */
	p_udf = udf_open(src_iso);
	if (p_udf == NULL)
		goto try_iso;
	uprintf("Disc image is an UDF image\n");

	p_udf_root = udf_get_root(p_udf, true, 0);
	if (p_udf_root == NULL) {
		uprintf("Couldn't locate UDF root directory\n");
		goto out;
	}
	if (scan_only) {
		if (udf_get_logical_volume_id(p_udf, iso_report.label, sizeof(iso_report.label)) <= 0)
			iso_report.label[0] = 0;
	}
	r = udf_extract_files(p_udf, p_udf_root, "");
	goto out;

try_iso:
	p_iso = iso9660_open_ext(src_iso, ISO_EXTENSION_ALL);
	if (p_iso == NULL) {
		uprintf("Unable to open image '%s'.\n", src_iso);
		goto out;
	}
	i_joliet_level = iso9660_ifs_get_joliet_level(p_iso);
	uprintf("Disc image is an ISO9660 image\n");
	if (scan_only) {
		if (iso9660_ifs_get_volume_id(p_iso, &vol_id)) {
			safe_strcpy(iso_report.label, sizeof(iso_report.label), vol_id);
			safe_free(vol_id);
		} else
			iso_report.label[0] = 0;
	}
	r = iso_extract_files(p_iso, "");

out:
	iso_blocking_status = -1;
	if (scan_only) {
		// We use the fact that UDF_BLOCKSIZE and ISO_BLOCKSIZE are the same here
		iso_report.projected_size = total_blocks * ISO_BLOCKSIZE;
		// We will link the existing isolinux.cfg from a syslinux.cfg we create
		// If multiple config file exist, choose the one with the shortest path
		if (iso_report.has_isolinux) {
			safe_strcpy(iso_report.cfg_path, sizeof(iso_report.cfg_path), config_path.Table[0]);
			for (i=1; i<config_path.Index; i++) {
				if (safe_strlen(iso_report.cfg_path) > safe_strlen(config_path.Table[i]))
					safe_strcpy(iso_report.cfg_path, sizeof(iso_report.cfg_path), config_path.Table[i]);
			}
			uprintf("Will use %s for Syslinux\n", iso_report.cfg_path);
		}
		StrArrayDestroy(&config_path);
	} else if (iso_report.has_isolinux) {
		safe_sprintf(syslinux_path, sizeof(syslinux_path), "%s\\syslinux.cfg", dest_dir);
		// Create a /syslinux.cfg (if none exists) that points to the existing isolinux cfg
		fd = fopen(syslinux_path, "r");
		if (fd == NULL) {
			fd = fopen(syslinux_path, "w");	// No "/syslinux.cfg" => create a new one
			if (fd == NULL) {
				uprintf("Unable to create %s - booting from USB will not work\n", syslinux_path);
				r = 1;
			} else {
				fprintf(fd, "DEFAULT loadconfig\n\nLABEL loadconfig\n  CONFIG %s\n", iso_report.cfg_path);
				for (i=safe_strlen(iso_report.cfg_path); (i>0)&&(iso_report.cfg_path[i]!='/'); i--);
				if (i>0) {
					iso_report.cfg_path[i] = 0;
					fprintf(fd, "  APPEND %s/\n", iso_report.cfg_path);
					iso_report.cfg_path[i] = '/';
				}
				uprintf("Created: %s\n", syslinux_path);
			}
		}
		fclose(fd);
	}
	SendMessage(hISOProgressDlg, UM_ISO_EXIT, 0, 0);
	if (p_iso != NULL)
		iso9660_close(p_iso);
	if (p_udf != NULL)
		udf_close(p_udf);
	if ((r != 0) && (FormatStatus == 0))
		FormatStatus = ERROR_SEVERITY_ERROR|FAC(FACILITY_STORAGE)|APPERR((scan_only?ERROR_ISO_SCAN:ERROR_ISO_EXTRACT));
	return (r == 0);
}