/*
 *  Window Maker miscelaneous function library
 *
 *  Copyright (c) 1997-2003 Alfredo K. Kojima
 *
 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */


#include "wconfig.h"

#include "WUtil.h"

#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <pwd.h>
#include <limits.h>

#ifndef PATH_MAX
#define PATH_MAX  1024
#endif


char*
wgethomedir()
{
    char *home = getenv("HOME");
    struct passwd *user;

    if (home)
        return home;

    user = getpwuid(getuid());
    if (!user) {
        wsyserror(_("could not get password entry for UID %i"), getuid());
        return "/";
    }
    if (!user->pw_dir) {
        return "/";
    } else {
        return user->pw_dir;
    }
}


static char*
getuserhomedir(char *username)
{
    struct passwd *user;

    user = getpwnam(username);
    if (!user) {
        wsyserror(_("could not get password entry for user %s"), username);
        return NULL;
    }
    if (!user->pw_dir) {
        return "/";
    } else {
        return user->pw_dir;
    }
}




char*
wexpandpath(char *path)
{
    char buffer2[PATH_MAX+2];
    char buffer[PATH_MAX+2];
    int i;

    memset(buffer, 0, PATH_MAX+2);

    if (*path=='~') {
        char *home;

        path++;
        if (*path=='/' || *path==0) {
            home = wgethomedir();
            strcat(buffer, home);
        } else {
            int j;
            j = 0;
            while (*path!=0 && *path!='/') {
                buffer2[j++] = *path;
                buffer2[j] = 0;
                path++;
            }
            home = getuserhomedir(buffer2);
            if (!home)
                return NULL;
            strcat(buffer, home);
        }
    }

    i = strlen(buffer);

    while (*path!=0) {
        char *tmp;

        if (*path=='$') {
            int j = 0;
            path++;
            /* expand $(HOME) or $HOME style environment variables */
            if (*path=='(') {
                path++;
                while (*path!=0 && *path!=')') {
                    buffer2[j++] = *(path++);
                    buffer2[j] = 0;
                }
                if (*path==')')
                    path++;
                tmp = getenv(buffer2);
                if (!tmp) {
                    buffer[i] = 0;
                    strcat(buffer, "$(");
                    strcat(buffer, buffer2);
                    strcat(buffer, ")");
                    i += strlen(buffer2)+3;
                } else {
                    strcat(buffer, tmp);
                    i += strlen(tmp);
                }
            } else {
                while (*path!=0 && *path!='/') {
                    buffer2[j++] = *(path++);
                    buffer2[j] = 0;
                }
                tmp = getenv(buffer2);
                if (!tmp) {
                    strcat(buffer, "$");
                    strcat(buffer, buffer2);
                    i += strlen(buffer2)+1;
                } else {
                    strcat(buffer, tmp);
                    i += strlen(tmp);
                }
            }
        } else {
            buffer[i++] = *path;
            path++;
        }
    }

    return wstrdup(buffer);
}


/* return address of next char != tok or end of string whichever comes first */
static char*
skipchar(char *string, char tok)
{
    while(*string!=0 && *string==tok)
        string++;

    return string;
}


/* return address of next char == tok or end of string whichever comes first */
static char*
nextchar(char *string, char tok)
{
    while(*string!=0 && *string!=tok)
        string++;

    return string;
}


/*
 *----------------------------------------------------------------------
 * findfile--
 * 	Finds a file in a : separated list of paths. ~ expansion is also
 * done.
 *
 * Returns:
 * 	The complete path for the file (in a newly allocated string) or
 * NULL if the file was not found.
 *
 * Side effects:
 * 	A new string is allocated. It must be freed later.
 *
 *----------------------------------------------------------------------
 */
char*
wfindfile(char *paths, char *file)
{
    char *path;
    char *tmp, *tmp2;
    int len, flen;
    char *fullpath;

    if (!file)
        return NULL;

    if (*file=='/' || *file=='~' || *file=='$' || !paths || *paths==0) {
        if (access(file, F_OK)<0) {
            fullpath = wexpandpath(file);
            if (!fullpath)
                return NULL;

            if (access(fullpath, F_OK)<0) {
                wfree(fullpath);
                return NULL;
            } else {
                return fullpath;
            }
        } else {
            return wstrdup(file);
        }
    }

    flen = strlen(file);
    tmp = paths;
    while (*tmp) {
        tmp = skipchar(tmp, ':');
        if (*tmp==0)
            break;
        tmp2 = nextchar(tmp, ':');
        len = tmp2 - tmp;
        path = wmalloc(len+flen+2);
        path = memcpy(path, tmp, len);
        path[len]=0;
        if (path[len-1] != '/')
            strcat(path, "/");
        strcat(path, file);
        fullpath = wexpandpath(path);
        wfree(path);
        if (fullpath) {
            if (access(fullpath, F_OK)==0) {
                return fullpath;
            }
            wfree(fullpath);
        }
        tmp = tmp2;
    }

    return NULL;
}


char*
wfindfileinlist(char **path_list, char *file)
{
    int i;
    char *path;
    int len, flen;
    char *fullpath;

    if (!file)
        return NULL;

    if (*file=='/' || *file=='~' || !path_list) {
        if (access(file, F_OK)<0) {
            fullpath = wexpandpath(file);
            if (!fullpath)
                return NULL;

            if (access(fullpath, F_OK)<0) {
                wfree(fullpath);
                return NULL;
            } else {
                return fullpath;
            }
        } else {
            return wstrdup(file);
        }
    }

    flen = strlen(file);
    for (i=0; path_list[i]!=NULL; i++) {
        len = strlen(path_list[i]);
        path = wmalloc(len+flen+2);
        path = memcpy(path, path_list[i], len);
        path[len]=0;
        strcat(path, "/");
        strcat(path, file);
        /* expand tilde */
        fullpath = wexpandpath(path);
        wfree(path);
        if (fullpath) {
            /* check if file exists */
            if (access(fullpath, F_OK)==0) {
                return fullpath;
            }
            wfree(fullpath);
        }
    }
    return NULL;
}



char*
wfindfileinarray(WMPropList *array, char *file)
{
    int i;
    char *path;
    int len, flen;
    char *fullpath;

    if (!file)
        return NULL;

    if (*file=='/' || *file=='~' || !array) {
        if (access(file, F_OK)<0) {
            fullpath = wexpandpath(file);
            if (!fullpath)
                return NULL;

            if (access(fullpath, F_OK)<0) {
                wfree(fullpath);
                return NULL;
            } else {
                return fullpath;
            }
        } else {
            return wstrdup(file);
        }
    }

    flen = strlen(file);
    for (i=0; i<WMGetPropListItemCount(array); i++) {
        WMPropList *prop;
        char *p;

        prop = WMGetFromPLArray(array, i);
        if (!prop)
            continue;
        p = WMGetFromPLString(prop);

        len = strlen(p);
        path = wmalloc(len+flen+2);
        path = memcpy(path, p, len);
        path[len]=0;
        strcat(path, "/");
        strcat(path, file);
        /* expand tilde */
        fullpath = wexpandpath(path);
        wfree(path);
        if (fullpath) {
            /* check if file exists */
            if (access(fullpath, F_OK)==0) {
                return fullpath;
            }
            wfree(fullpath);
        }
    }
    return NULL;
}