/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2026 Olaf Wintermann. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "sab.h"

#include "../../util/util.h"
#include "../../util/pblock.h"


int rq_match(pblock *pb, const pb_key *param, Request *rq, const char *match, const char *notmatch, int *error) {
    if(error) {
        *error = 0;
    }
    
    if(!match && !notmatch) {
        return 1;
    }
    
    char *str = pblock_findkeyval(param, rq->reqpb);
    if(!str) {
        str = "";
    }
    
    int ret = 0;
    if(match) {
        regex_t regex;
        if(regcomp(&regex, match, REG_EXTENDED)) {
            log_ereport(LOG_MISCONFIG, "sab: cannot compile regex pattern %s", match);
            if(error) {
                *error = 1;
            }
            return 0;
        }

        regmatch_t rm;
        if(regexec(&regex, str, 1, &rm, 0) == 0) {
            ret = 1;
        }
        
        regfree(&regex);
    } else {
        ret = 1;
    }
    
    
    if(notmatch) {
        regex_t regex;
        if(regcomp(&regex, notmatch, REG_EXTENDED)) {
            log_ereport(LOG_MISCONFIG, "sab: cannot compile regex pattern %s", match);
            if(error) {
                *error = 1;
            }
            return 0;
        }

        regmatch_t rm;
        if(regexec(&regex, str, 1, &rm, 0) == 0) {
            ret = 0;
        }
        
        regfree(&regex);
    }
    
    return ret;
}

int sab_url_match(pblock *pb, Request *rq, int *error) {
    char *match = pblock_findval("match", pb);
    char *notmatch = pblock_findval("notmatch", pb);
    return rq_match(pb, pb_key_uri, rq, match, notmatch, error);
}

int sab_query_match(pblock *pb, Request *rq, int *error) {
    char *match = pblock_findval("query_match", pb);
    char *notmatch = pblock_findval("query_notmatch", pb);
    return rq_match(pb, pb_key_query, rq, match, notmatch, error);
}

// Simple detection based on a dumb cookie. If not it adds
// is-bot to rq->vars.
// 
// Args:
//     cookie: cookie name
//     value: cookie value (optional)
//     match: only apply this check if the request url matches this regex
//     notmatch: the url should also not match this pattern
//     query_match: only apply this check if the request query matches this regex
//     query_notmatch: the query should also not match this pattern
//     
int sab_has_cookie(pblock *pb, Session *sn, Request *rq) {
    int error;
    int match = sab_url_match(pb, rq, &error);
    if(!match) {
        return error ? REQ_ABORTED : REQ_NOACTION;
    }
    match = sab_query_match(pb, rq, &error);
    if(!match) {
        return error ? REQ_ABORTED : REQ_NOACTION;
    }
    
    char *cookie_name = pblock_findval("cookie", pb);
    char *cookie_value = pblock_findval("value", pb);
    if(!cookie_name) {
        log_ereport(LOG_MISCONFIG, "sab-has-cookie: no cookie specified");
        return REQ_ABORTED;
    }
    
    WSBool has_cookie = FALSE;
    char *cookie = pblock_findkeyval(pb_key_cookie, rq->headers);
    if(cookie) {
        char *value = util_cookie_find(cookie, cookie_name);
        if(value) {
            if(cookie_value) {
                has_cookie = !strcmp(cookie_value, value);
            } else {
                has_cookie = TRUE;
            }
        }
    }
    
    if(!has_cookie) {
        pblock_nvinsert("is-bot", "1", rq->vars);
    }
    
    return REQ_NOACTION;
}