/*
 * ignorecase.c:  If the requested file is not there, check to see if it
 *                is simply a matter of case.  This only checks the file
 *                part of the URL, not the directories.
 *
 * Ported from Apache module mod_speling.c (Alexei Kosut) by
 *   Rob Crittenden (rcrit@greyoak.com)
 *
 * How to install this program:
 *
 *    Add the following lines to your obj.conf:
 *
 *    Init fn=load-modules shlib=<path to ignorecase.so> funcs=ignorecase
 *    PathCheck fn="ignorecase"
 *
 *    NOTE:  This should be the _last_ PathCheck
 *
 */

#include "nsapi.h"

/* Forward declarations */
int revindex(const char *s, char c);
char * STRNDUP(const char *s, int n);

/* 
 * ignorecase()
 *
 * Try really hard to find the requested file and update uri and path
 * accordingly.
 *
 */
NSAPI_PUBLIC int ignorecase(pblock *pb, Session *sn, Request *rq)
{
    int return_value=REQ_NOACTION;
    char * path;  /* original path to the file */
    char * new_path; /* will hold the new path */
    pb_param *pblock_path; /* pointer to path in the pblock */
    char * uri; /* the original URI */
    char * url; /* the modified URI */
    char * filename;
    char * method;
    int fileindex;
    char * directory;  /* the physical path to the file */
    char * urld; /* the URI path to the file */
    SYS_DIR ds;
    SYS_DIRENT *d;
    struct stat fi;

    if (!(path = pblock_findval("path", rq->vars)))
    {
 	log_error(LOG_WARN, "ignorecase", sn, rq, "No path specified");
	return_value = REQ_NOACTION;
	goto done;
    }
    
    /* only do this for GET's and POST's */
    if ((method = pblock_findval( "method", rq->reqpb)))
        if (strcmp( method, "GET" ) && strcmp( method, "POST")) {
            return_value = REQ_NOACTION;
	    goto done;
	}

    /* If the file is there, do nothing */
    if (system_stat(path, &fi) != -1) {
	return_value = REQ_NOACTION;
	goto done;
    }

    /* break apart the requested filename from the path */
    fileindex = revindex(path, '/');
    if (fileindex == -1) {
	return_value = REQ_NOACTION;
	goto done;
    }
    directory = STRNDUP(path, fileindex);

    uri = pblock_findval("uri", rq->reqpb);

    if(!(filename = strrchr(path,FILE_PATHSEP)))
	filename = uri;
    else
	++filename; 

    /* open the directory to find the file, if I can't open it, do nothing,
       let send-file deal with it */
    if(!(ds = dir_open(directory))) {
        return_value = REQ_NOACTION;
	goto done;
    }

    while( (d = dir_read(ds)) ) {
        if(d->d_name[0] == '.')
            continue;

	/* if the file matches, we're done */
	if (strcasecmp(filename, d->d_name) == 0) {

	    /* put the corrected path into the pblock */
	    new_path = (char *)MALLOC(strlen(path));
	    util_sprintf(new_path,"%s/%s", directory, d->d_name);
	    pblock_path = pblock_find("path", rq->vars);
	    FREE(pblock_path->value);
	    pblock_path->value = new_path;

	    /* The server caches the stat() of the current path. Update it. */
	    (void) request_stat_path(NULL, rq);

	    /* put the corrected uri into the pblock */
	    fileindex = revindex(uri, '/');
	    urld = (char *)STRNDUP(uri, fileindex);
	    url = (char *)MALLOC(strlen(uri));
	    util_sprintf(url,"%s/%s", urld, d->d_name);
	    param_free(pblock_remove("uri", rq->reqpb));
	    pblock_nvinsert("uri", url, rq->reqpb);

	    return_value = REQ_PROCEED;
	    goto done;
	}
    }

    /* exit gracefully (hopefully) */
done:
    if (url) FREE(url);
    if (directory) FREE(directory);
    if (urld) FREE(urld);

    return(return_value);
}

/* find a character looking through a string in reverse */
int revindex(const char *s, char c)
{
    int x;

    for (x=strlen(s) -1; x!= -1;x--)
	if (s[x] == c)
		return x;

    return -1;
}

/* duplicate a string up to n characters long */
char * STRNDUP(const char *s, int n)
{
    char * result;

    if (s == NULL)
	return NULL;

    result = (char *)MALLOC(n+1);
    memcpy(result, s, n);
    result[n] = '\0';
    return result;
}