/*
  Hatari - zip.c

  This file is distributed under the GNU Public License, version 2 or at
  your option any later version. Read the file gpl.txt for details.

  Zipped disk support, uses zlib
*/
const char ZIP_rcsid[] = "Hatari $Id: zip.c,v 1.22 2007/01/16 18:42:59 thothy Exp $";

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include <dirent.h>
#include <sys/types.h>

#include <zlib.h>

#include "main.h"
#include "dim.h"
#include "file.h"
#include "floppy.h"
#include "log.h"
#include "msa.h"
#include "st.h"
#include "unzip.h"
#include "zip.h"

#ifdef QNX
#include <sys/dir.h>
#define dirent direct
#endif

/* #define SAVE_TO_ZIP_IMAGES */

#define ZIP_PATH_MAX  256

#define ZIP_FILE_ST   1
#define ZIP_FILE_MSA  2
#define ZIP_FILE_DIM  3


/* Possible disk image extensions to scan for */
static const char * const pszDiskNameExts[] =
{
  ".msa",
  ".st",
  ".dim",
  NULL
};


/*-----------------------------------------------------------------------*/
/**
 * Does filename end with a .ZIP extension? If so, return TRUE
 */
BOOL ZIP_FileNameIsZIP(char *pszFileName)
{
	return File_DoesFileExtensionMatch(pszFileName,".zip");
}


/*-----------------------------------------------------------------------*/
/**
 * Check if a file name contains a slash or backslash and return its position.
 */
static int Zip_FileNameHasSlash(char *fn)
{
	int i=0;

	while (fn[i] != '\0')
	{
		if (fn[i] == '\\' || fn[i] == '/')
			return i;
		i++;
	}
	return -1;
}


/*-----------------------------------------------------------------------*/
/**
 * Returns a list of files from a zip file. returns NULL on failure,
 * returns a pointer to an array of strings if successful. Sets nfiles
 * to the number of files.
 */
zip_dir *ZIP_GetFiles(char *pszFileName)
{
	int nfiles;
	unsigned int i;
	unz_global_info gi;
	int err;
	unzFile uf;
	char **filelist;
	unz_file_info file_info;
	char filename_inzip[ZIP_PATH_MAX];
	zip_dir *zd;

	uf = unzOpen(pszFileName);
	if (uf == NULL)
	{
		Log_Printf(LOG_ERROR, "ZIP_GetFiles: Cannot open %s\n", pszFileName);
		return NULL;
	}

	err = unzGetGlobalInfo(uf,&gi);
	if (err != UNZ_OK)
	{
		Log_Printf(LOG_ERROR, "Error %d with zipfile in unzGetGlobalInfo \n",err);
		return NULL;
	}

	/* allocate a file list */
	filelist = (char **)malloc(gi.number_entry*sizeof(char *));
	if (!filelist)
	{
		perror("ZIP_GetFiles");
		return NULL;
	}

	nfiles = gi.number_entry;  /* set the number of files */

	for (i = 0; i < gi.number_entry; i++)
	{
		err = unzGetCurrentFileInfo(uf, &file_info, filename_inzip, ZIP_PATH_MAX, NULL, 0, NULL, 0);
		if (err != UNZ_OK)
		{
			free(filelist);
			return NULL;
		}

		filelist[i] = (char *)malloc(strlen(filename_inzip) + 1);
		if (!filelist[i])
		{
			perror("ZIP_GetFiles");
			free(filelist);
			return NULL;
		}

		strcpy(filelist[i], filename_inzip);
		if ((i+1) < gi.number_entry)
		{
			err = unzGoToNextFile(uf);
			if (err != UNZ_OK)
			{
				Log_Printf(LOG_ERROR, "ZIP_GetFiles: Error in ZIP-file\n");
				/* deallocate memory */
				for (; i > 0; i--)
					free(filelist[i]);
				free(filelist);
				return NULL;
			}
		}
	}

	unzClose(uf);

	zd = (zip_dir *)malloc(sizeof(zip_dir));
	if (!zd)
	{
		perror("ZIP_GetFiles");
		free(filelist);
		return NULL;
	}
	zd->names = filelist;
	zd->nfiles = nfiles;

	return zd;
}


/*-----------------------------------------------------------------------*/
/**
 * Free the memory that has been allocated for a zip_dir.
 */
void ZIP_FreeZipDir(zip_dir *f_zd)
{
	while (f_zd->nfiles > 0)
	{
		f_zd->nfiles--;
		free(f_zd->names[f_zd->nfiles]);
		f_zd->names[f_zd->nfiles] = NULL;
	}
	free(f_zd->names);
	f_zd->names = NULL;
	free(f_zd);
}


/*-----------------------------------------------------------------------*/
/**
 *   Returns a list of files from the directory (dir) in a zip file list (zip)
 *   sets entries to the number of entries and returns a dirent structure, or
 *   NULL on failure. NOTE: only f_name is set in the dirent structures. 
 */
struct dirent **ZIP_GetFilesDir(zip_dir *zip, char *dir, int *entries)
{
	int i,j;
	zip_dir *files;
	char *temp;
	BOOL flag;
	int slash;
	struct dirent **fentries;

	files = (zip_dir *)malloc(sizeof(zip_dir));
	if (!files)
	{
		perror("ZIP_GetFilesDir");
		return NULL;
	}

	files->names = (char **)malloc((zip->nfiles + 1) * sizeof(char *));
	if (!files->names)
	{
		perror("ZIP_GetFilesDir");
		free(files);
		return NULL;
	}

	/* add ".." directory */
	files->nfiles = 1;
	temp = (char *)malloc(4);
	if (!temp)
		return NULL;
	temp[0] = temp[1] = '.';
	temp[2] = '/';
	temp[3] = '\0';
	files->names[0] = temp;

	for (i = 0; i < zip->nfiles; i++)
	{
		if (strlen(zip->names[i]) > strlen(dir))
		{
			if (strncasecmp(zip->names[i], dir, strlen(dir)) == 0)
			{
				temp = zip->names[i];
				temp = (char *)(temp + strlen(dir));
				if (temp[0] != '\0')
				{
					if ((slash=Zip_FileNameHasSlash(temp)) > 0)
					{
						/* file is in a subdirectory, add this subdirectory if it doesn't exist in the list */
						flag = FALSE;
						for (j = files->nfiles-1; j > 0; j--)
						{
							if (strncasecmp(temp, files->names[j], slash+1) == 0)
								flag=TRUE;
						}
						if (flag == FALSE)
						{
							files->names[files->nfiles] = (char *)malloc(slash+1);
							if (!files->names[files->nfiles])
							{
								perror("ZIP_GetFilesDir");
								return NULL;
							}
							strncpy(files->names[files->nfiles], temp, slash+1);
							((char *)files->names[files->nfiles])[slash+1] = '\0';
							files->nfiles++;
						}
					}
					else
					{
						/* add a filename */
						files->names[files->nfiles] = (char *)malloc(strlen(temp)+1);
						if (!files->names[files->nfiles])
						{
							perror("ZIP_GetFilesDir");
							return NULL;
						}
						strncpy(files->names[files->nfiles], temp, strlen(temp));
						((char *)files->names[files->nfiles])[strlen(temp)] = '\0';
						files->nfiles++;
					}
				}
			}
		}
	}

	/* copy to a dirent structure */
	*entries = files->nfiles;
	fentries = (struct dirent **)malloc(sizeof(struct dirent *)*files->nfiles);
	if (!fentries)
	{
		perror("ZIP_GetFilesDir");
		ZIP_FreeZipDir(files);
		return NULL;
	}
	for (i = 0; i < files->nfiles; i++)
	{
		fentries[i] = (struct dirent *)malloc(sizeof(struct dirent));
		if (!fentries[i])
		{
			perror("ZIP_GetFilesDir");
			return NULL;
		}
		strcpy(fentries[i]->d_name, files->names[i]);
	}

	ZIP_FreeZipDir(files);

	return fentries;
}


/*-----------------------------------------------------------------------*/
/**
 * Check an image file in the archive, return the uncompressed length
 */
static long ZIP_CheckImageFile(unzFile uf, char *filename, int *pDiskType)
{
	unz_file_info file_info;

	if (unzLocateFile(uf,filename, 0) != UNZ_OK)
	{
		Log_Printf(LOG_ERROR, "Error: File \"%s\" not found in the archive!", filename);
		return -1;
	}

	if (unzGetCurrentFileInfo(uf, &file_info, filename, ZIP_PATH_MAX, NULL, 0, NULL, 0) != UNZ_OK)
	{
		Log_Printf(LOG_ERROR, "Error with zipfile in unzGetCurrentFileInfo \n");
		return -1;
	}

	/* check for a .msa or .st extention */
	if (MSA_FileNameIsMSA(filename, FALSE))
	{
		*pDiskType = ZIP_FILE_MSA;
		return file_info.uncompressed_size;
	}

	if (ST_FileNameIsST(filename, FALSE))
	{
		*pDiskType = ZIP_FILE_ST;
		return file_info.uncompressed_size;
	}

	if (DIM_FileNameIsDIM(filename, FALSE))
	{
		*pDiskType = ZIP_FILE_DIM;
		return file_info.uncompressed_size;
	}

	Log_Printf(LOG_ERROR, "Not an .ST, .MSA or .DIM file.\n");
	return 0;
}

/*-----------------------------------------------------------------------*/
/**
 * Return the first matching file in a zip, or NULL on failure
 */
static char *ZIP_FirstFile(char *filename, const char * const ppsExts[])
{
	zip_dir *files;
	int i, j;
	char *name;

	files = ZIP_GetFiles(filename);
	if (files == NULL)
		return NULL;

	name = malloc(ZIP_PATH_MAX);
	if (!name)
	{
		perror("ZIP_FirstFile");
		return NULL;
	}

	/* Do we have to scan for a certain extension? */
	if (ppsExts)
	{
		name[0] = '\0';
		for(i = files->nfiles-1; i >= 0; i--)
		{
			for (j = 0; ppsExts[j] != NULL; j++)
			{
				if (File_DoesFileExtensionMatch(files->names[i], ppsExts[j]))
				{
					strncpy(name, files->names[i], ZIP_PATH_MAX);
					break;
				}
			}
		}
	}
	else
	{
		/* There was no extension given -> use the very first name */
		strncpy(name, files->names[0], ZIP_PATH_MAX);
	}

	/* free the files */
	ZIP_FreeZipDir(files);

	if (name[0] == '\0')
		return NULL;
	return name;
}


/*-----------------------------------------------------------------------*/
/**
 * Extract a file (filename) from a ZIP-file (uf), the number of 
 * bytes to uncompress is size. Returns a pointer to a buffer containing
 * the uncompressed data, or NULL.
 */
static void *ZIP_ExtractFile(unzFile uf, char *filename, uLong size)
{
	int err = UNZ_OK;
	char filename_inzip[ZIP_PATH_MAX];
	void* buf;
	uInt size_buf;
	unz_file_info file_info;


	if (unzLocateFile(uf,filename, 0) != UNZ_OK)
	{
		Log_Printf(LOG_ERROR, "ZIP_ExtractFile: could not find file in archive\n");
		return NULL;
	}

	err = unzGetCurrentFileInfo(uf,&file_info,filename_inzip,sizeof(filename_inzip),NULL,0,NULL,0);

	if (err != UNZ_OK)
	{
		Log_Printf(LOG_ERROR, "ZIP_ExtractFile: could not get file info\n");
		return NULL;
	}

	size_buf = size;
	buf = malloc(size_buf);
	if (!buf)
	{
		perror("ZIP_ExtractFile");
		return NULL;
	}

	err = unzOpenCurrentFile(uf);
	if (err != UNZ_OK)
	{
		Log_Printf(LOG_ERROR, "ZIP_ExtractFile: could not open file\n");
		return NULL;
	}

	do
	{
		err = unzReadCurrentFile(uf,buf,size_buf);
		if (err < 0)
		{
			Log_Printf(LOG_ERROR, "ZIP_ExtractFile: could not read file\n");
			return NULL;
		}
	}
	while (err > 0);

	return buf;
}


/*-----------------------------------------------------------------------*/
/**
 * Load disk image from a .ZIP archive into memory, and return the number
 * of bytes loaded.
 */
Uint8 *ZIP_ReadDisk(char *pszFileName, char *pszZipPath, long *pImageSize)
{
	uLong ImageSize=0;
	unzFile uf=NULL;
	Uint8 *buf;
	int nDiskType = -1;
	BOOL pathAllocated=FALSE;
	Uint8 *pDiskBuffer = NULL;

	*pImageSize = 0;

	uf = unzOpen(pszFileName);
	if (uf == NULL)
	{
		Log_Printf(LOG_ERROR, "Cannot open %s\n", pszFileName);
		return NULL;
	}

	if (pszZipPath == NULL || pszZipPath[0] == 0)
	{
		pszZipPath = ZIP_FirstFile(pszFileName, pszDiskNameExts);
		if (pszZipPath == NULL)
		{
			Log_Printf(LOG_ERROR, "Cannot open %s\n", pszFileName);
			unzClose(uf);
			return NULL;
		}
		pathAllocated=TRUE;
	}

	ImageSize = ZIP_CheckImageFile(uf, pszZipPath, &nDiskType);
	if (ImageSize <= 0)
	{
		unzClose(uf);
		return NULL;
	}

	/* extract to buf */
	buf=ZIP_ExtractFile(uf, pszZipPath, ImageSize);
	unzCloseCurrentFile(uf);
	unzClose(uf);
	if (buf == NULL)
	{
		return NULL;  /* failed extraction, return error */
	}

	if (nDiskType == ZIP_FILE_ST)
	{
		/* ST image => return buffer directly */
		pDiskBuffer = buf;
	}
	else if (nDiskType == ZIP_FILE_MSA)
	{
		/* uncompress the MSA file */
		pDiskBuffer = MSA_UnCompress(buf, (long *)&ImageSize);
	}
	else if (nDiskType == ZIP_FILE_DIM)
	{
		/* Skip DIM header */
		ImageSize -= 32;
		pDiskBuffer = malloc(ImageSize);
		if (pDiskBuffer)
			memcpy(pDiskBuffer, buf+32, ImageSize);
		else
			perror("ZIP_ReadDisk");
	}

	/* Free the buffers */
	if (pDiskBuffer != buf)
		free(buf);
	if (pathAllocated == TRUE)
		free(pszZipPath);

	if (pDiskBuffer != NULL)
		*pImageSize = ImageSize;

	return pDiskBuffer;
}


/*-----------------------------------------------------------------------*/
/**
 * Save .ZIP file from memory buffer. Returns TRUE is all OK
 *
 * Not yet implemented.
 */
BOOL ZIP_WriteDisk(char *pszFileName,unsigned char *pBuffer,int ImageSize)
{
	return FALSE;
}


/*-----------------------------------------------------------------------*/
/**
 * Load first file from a .ZIP archive into memory, and return the number
 * of bytes loaded.
 */
Uint8 *ZIP_ReadFirstFile(char *pszFileName, long *pImageSize, const char * const ppszExts[])
{
	unzFile uf=NULL;
	Uint8 *pBuffer;
	char *pszZipPath;
	unz_file_info file_info;

	*pImageSize = 0;

	/* Open the ZIP file */
	uf = unzOpen(pszFileName);
	if (uf == NULL)
	{
		Log_Printf(LOG_ERROR, "Cannot open '%s'\n", pszFileName);
		return NULL;
	}

	/* Locate the first file in the ZIP archive */
	pszZipPath = ZIP_FirstFile(pszFileName, ppszExts);
	if (pszZipPath == NULL)
	{
		Log_Printf(LOG_ERROR, "Failed to locate first file in '%s'\n", pszFileName);
		unzClose(uf);
		return NULL;
	}

	if (unzLocateFile(uf, pszZipPath, 0) != UNZ_OK)
	{
		Log_Printf(LOG_ERROR, "Error: Can not locate '%s' in the archive!", pszZipPath);
		return NULL;
	}

	/* Get file information (file size!) */
	if (unzGetCurrentFileInfo(uf, &file_info, pszZipPath, ZIP_PATH_MAX, NULL, 0, NULL, 0) != UNZ_OK)
	{
		Log_Printf(LOG_ERROR, "Error with zipfile in unzGetCurrentFileInfo.\n");
		return NULL;
	}

	/* Extract to buffer */
	pBuffer = ZIP_ExtractFile(uf, pszZipPath, file_info.uncompressed_size);

	/* And close the file */
	unzCloseCurrentFile(uf);
	unzClose(uf);

	free(pszZipPath);

	if (pBuffer)
		*pImageSize = file_info.uncompressed_size;

	return pBuffer;
}