/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 *   Mupen64plus-core - osal/files_unix.c                                  *
 *   Mupen64Plus homepage: http://code.google.com/p/mupen64plus/           *
 *   Copyright (C) 2009 Richard Goedeken                                   *
 *                                                                         *
 *   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 2 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, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.          *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
                       
/* This file contains the definitions for the unix-specific file handling
 * functions
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <limits.h>

#include "files.h"
#include "api/m64p_types.h"
#include "api/callbacks.h"

#ifdef __APPLE__
/* OS X code for app bundle handling */
#include <CoreFoundation/CoreFoundation.h>

// dynamic data path detection onmac
bool macSetBundlePath(char* buffer)
{
    // the following code will enable mupen to find its data when placed in an app bundle on mac OS X.
    // returns true if path is set, returns false if path was not set
    char path[1024];
    CFBundleRef main_bundle = CFBundleGetMainBundle(); assert(main_bundle);
    CFURLRef main_bundle_URL = CFBundleCopyBundleURL(main_bundle); assert(main_bundle_URL);
    CFStringRef cf_string_ref = CFURLCopyFileSystemPath( main_bundle_URL, kCFURLPOSIXPathStyle); assert(cf_string_ref);
    CFStringGetCString(cf_string_ref, path, 1024, kCFStringEncodingASCII);
    CFRelease(main_bundle_URL);
    CFRelease(cf_string_ref);
    
    if (strstr( path, ".app" ) != 0)
    {
        DebugMessage(M64MSG_VERBOSE, "checking whether we are using an app bundle: yes");
        // executable is inside an app bundle, use app bundle-relative paths
        sprintf(buffer, "%s/Contents/Resources/", path);
        return true;
    }
    else
    {
        DebugMessage(M64MSG_VERBOSE, "checking whether we are using an app bundle: no");
        return false;
    }
}
#endif

/* definitions for system directories to search when looking for shared data files */
#if defined(SHAREDIR)
  #define XSTR(S) STR(S) /* this wacky preprocessor thing is necessary to generate a quote-enclosed */
  #define STR(S) #S      /* copy of the SHAREDIR macro, which is defined by the makefile via gcc -DSHAREDIR="..." */
  static const int   datasearchdirs = 4;
  static const char *datasearchpath[4] = { XSTR(SHAREDIR), "/usr/local/share/mupen64plus",  "/usr/share/mupen64plus", "./" };
  #undef STR
  #undef XSTR
#else
  static const int   datasearchdirs = 3;
  static const char *datasearchpath[3] = { "/usr/local/share/mupen64plus",  "/usr/share/mupen64plus", "./" };
#endif

/* local functions */

static int get_xdg_dir(char *destpath, const char *envvar, const char *subdir)
{
    struct stat fileinfo;
    const char *envpath = getenv(envvar);

    /* error if this environment variable doesn't return a good string */
    if (envpath == NULL || strlen(envpath) < 1)
        return 1;

    /* error if path returned by the environemnt variable isn't a valid path to a directory */
    if (stat(envpath, &fileinfo) != 0 || !S_ISDIR(fileinfo.st_mode))
        return 2;

    /* append the given sub-directory to the path given by the environment variable */
    strcpy(destpath, envpath);
    if (destpath[strlen(destpath)-1] != '/')
        strcat(destpath, "/");
    strcat(destpath, subdir);

    /* try to create the resulting directory tree, or return successfully if it already exists */
    if (osal_mkdirp(destpath, 0700) != 0)
    {
        DebugMessage(M64MSG_ERROR, "Couldn't create directory: %s", destpath);
        return 3;
    }

    /* Success */
    return 0;
}

static int search_dir_file(char *destpath, const char *path, const char *filename)
{
    struct stat fileinfo;

    /* sanity check to start */
    if (destpath == NULL || path == NULL || filename == NULL)
        return 1;

    /* build the full filepath */
    strcpy(destpath, path);
    if (destpath[strlen(destpath)-1] != '/')
        strcat(destpath, "/");
    strcat(destpath, filename);

    /* test for a valid file */
    if (stat(destpath, &fileinfo) != 0)
        return 2;
    if (!S_ISREG(fileinfo.st_mode))
        return 3;

    /* success - file exists and is a regular file */
    return 0;
}

/* global functions */

int osal_mkdirp(const char *dirpath, int mode)
{
    struct stat fileinfo;
    int dirpathlen = strlen(dirpath);
    char *currpath = strdup(dirpath);

    /* first, break the path into pieces by replacing all of the slashes wil NULL chars */
    while (strlen(currpath) > 1)
    {
        char *lastslash = strrchr(currpath, '/');
        if (lastslash == NULL)
            break;
        *lastslash = 0;
    }
    
    /* then re-assemble the path from left to right until we get to a directory that doesn't exist */
    while (strlen(currpath) < dirpathlen)
    {
        if (strlen(currpath) > 0 && stat(currpath, &fileinfo) != 0)
            break;
        currpath[strlen(currpath)] = '/';
    }

    /* then walk up the path chain, creating directories along the way */
    do
    {
        if (stat(currpath, &fileinfo) != 0)
        {
            if (mkdir(currpath, mode) != 0)
            {
                free(currpath);
                return 1;        /* mkdir failed */
            }
        }
        if (strlen(currpath) == dirpathlen)
            break;
        else
            currpath[strlen(currpath)] = '/';
    } while (1);
    
    free(currpath);        
    return 0;
}

const char * osal_get_shared_filepath(const char *filename, const char *firstsearch, const char *secondsearch)
{
    static char retpath[PATH_MAX];
    int i;

    /* if caller gave us any directories to search, then look there first */
    if (firstsearch != NULL && search_dir_file(retpath, firstsearch, filename) == 0)
        return retpath;
    if (secondsearch != NULL && search_dir_file(retpath, secondsearch, filename) == 0)
        return retpath;

#ifdef __APPLE__
    /* Special case : OS X bundles */
    static char buf[1024];
    if (macSetBundlePath(buf))
    {
        sprintf(retpath, "%s%s", buf, filename);
        return retpath;
    }
#endif

    /* otherwise check our standard paths */
    for (i = 0; i < datasearchdirs; i++)
    {
        if (search_dir_file(retpath, datasearchpath[i], filename) == 0)
            return retpath;
    }

    /* we couldn't find the file */
    return NULL;
}

const char * osal_get_user_configpath(void)
{
    static char retpath[PATH_MAX];
    int rval;
    
    /* first, try the XDG_CONFIG_HOME environment variable */
    rval = get_xdg_dir(retpath, "XDG_CONFIG_HOME", "mupen64plus/");
    if (rval == 0)
        return retpath;

    /* then try the HOME environment variable */
    rval = get_xdg_dir(retpath, "HOME", ".config/mupen64plus/");
    if (rval == 0)
        return retpath;

    /* otherwise we are in trouble */
    if (rval < 3)
        DebugMessage(M64MSG_ERROR, "Failed to get configuration directory; $HOME is undefined or invalid.");
    return NULL;
}

const char * osal_get_user_datapath(void)
{
    static char retpath[PATH_MAX];
    int rval;
    
    /* first, try the XDG_DATA_HOME environment variable */
    rval = get_xdg_dir(retpath, "XDG_DATA_HOME", "mupen64plus/");
    if (rval == 0)
        return retpath;

    /* then try the HOME environment variable */
    rval = get_xdg_dir(retpath, "HOME", ".local/share/mupen64plus/");
    if (rval == 0)
        return retpath;

    /* otherwise we are in trouble */
    if (rval < 3)
        DebugMessage(M64MSG_ERROR, "Failed to get data directory; $HOME is undefined or invalid.");
    return NULL;
}

const char * osal_get_user_cachepath(void)
{
    static char retpath[PATH_MAX];
    int rval;
    
    /* first, try the XDG_CACHE_HOME environment variable */
    rval = get_xdg_dir(retpath, "XDG_CACHE_HOME", "mupen64plus/");
    if (rval == 0)
        return retpath;

    /* then try the HOME environment variable */
    rval = get_xdg_dir(retpath, "HOME", ".cache/mupen64plus/");
    if (rval == 0)
        return retpath;

    /* otherwise we are in trouble */
    if (rval < 3)
        DebugMessage(M64MSG_ERROR, "Failed to get cache directory; $HOME is undefined or invalid.");
    return NULL;
}


