#define SC_CAPI(c, b, h, e, ...) sc_api(c, b, h, 0##__VA_OPT__(1), e __VA_OPT__(,) __VA_ARGS__)
#define SC_CAPIX(c, b, h, e, ...) sc_capix(c, b, h, 0##__VA_OPT__(1), e __VA_OPT__(,) __VA_ARGS__)
char * sc_api (struct sc_cache * c, char * body, char * headers, int isfmt, char * endpoint, ...) {
	if (!c || !endpoint)
		return NULL;
	size_t va_count = parse_printf_format(endpoint, 0, NULL);
	char * endpoint_formatted = NULL;
	long response_code = 0;
	if (isfmt && va_count > 0 && endpoint_formatted == NULL) {
		va_list ap, ap2;
		va_start(ap, endpoint);
		va_copy(ap2, ap);
		size_t strlenm = vsnprintf(NULL, 0, endpoint, ap);
		endpoint_formatted = malloc(sizeof(char)*strlenm+1);
		vsnprintf(endpoint_formatted, strlenm+1, endpoint, ap2);
		va_end(ap);
		va_end(ap2);
	}
	if (!headers)
		headers = "";
	char * hedrs = malloc(sizeof(char)*strlen(headers)+strlen(SC_HTTP_HEADERS)+1);
	strcpy(hedrs, SC_HTTP_HEADERS);
	strcat(hedrs, headers);
	char * contentType = NULL;
	char * redir = NULL;
	char * buf = malloc(sizeof(char)*SC_HTTP_RBUFSIZE);
	size_t buf_sizeof = SC_HTTP_RBUFSIZE;
	size_t buf_length = 0;
	int readstatus = 0;
	void * r = xmlNanoHTTPMethodRedir(
			endpoint_formatted ? endpoint_formatted : endpoint,
			body ? "POST" : "GET",
			body,
			&contentType,
			&redir,
			hedrs,
			body ? strlen(body) : 0
			);
	if (!r) {
		SC_LOG(SC_LOG_ERROR, c, "!r, endpoint: %s", endpoint_formatted ? endpoint_formatted : endpoint);
		goto rc;
	}
	response_code = xmlNanoHTTPReturnCode(r);
	if (!(response_code - 200 >= 0 && response_code - 200 < 100)) {
		SC_LOG(SC_LOG_ERROR, c, "response_code == %ld, endpoint: %s", response_code, endpoint_formatted ? endpoint_formatted:endpoint);
	}
	while ((readstatus = xmlNanoHTTPRead(r, buf+buf_length, buf_sizeof-buf_length)) > 0) {
		buf_length += readstatus;
		if (buf_sizeof-buf_length < SC_HTTP_RBUFSIZE) {
			buf_sizeof *= SC_REALLOC_K;
			buf = realloc(buf, sizeof(char)*buf_sizeof);
		}
	}
	if (readstatus == -1)
		SC_LOG(SC_LOG_ERROR, c, "readstatus == -1, endpoint: %s", endpoint_formatted ? endpoint_formatted : endpoint);
	xmlNanoHTTPClose(r);
	SC_LOG(SC_LOG_DEBUG, c, "contentType = %s, redir = %s", contentType ? contentType : "NULL", redir ? redir : "NULL");
rc:
	free(endpoint_formatted);
	free(contentType);
	free(redir);
	free(hedrs);
	return buf;
}
htmlDocPtr sc_capix (struct sc_cache * c, char * body, char * headers, int isfmt, char * endpoint, ...) {
	if (!c || !endpoint)
		return NULL;
	size_t va_count = parse_printf_format(endpoint, 0, NULL);
	char * endpoint_formatted = NULL;
	if (isfmt && va_count > 0 && endpoint_formatted == NULL) {
		va_list ap, ap2;
		va_start(ap, endpoint);
		va_copy(ap2, ap);
		size_t strlenm = vsnprintf(NULL, 0, endpoint, ap);
		endpoint_formatted = malloc(sizeof(char)*strlenm+1);
		vsnprintf(endpoint_formatted, strlenm+1, endpoint, ap2);
		va_end(ap);
		va_end(ap2);
	}
	char * buf = sc_api(c, body, headers, 0, endpoint_formatted ? endpoint_formatted : endpoint);
	htmlDocPtr htmldoc = parseHtmlDocument(buf, endpoint_formatted ? endpoint_formatted : endpoint);
	free(buf);
	free(endpoint_formatted);
	return htmldoc;
}
char * sc_find_class (char * haystack, const char * definition) { /* you must free class after calling */
	if (!haystack || !definition)
		return NULL;
	char * class = strstr(haystack, definition);
	if (!class)
		return NULL;
	int found = 0;
	for (; class > haystack; class--)
		if (class[-1] == '.' && (found = 1))
			break;
	if (!found)
		return NULL;
	char * endofclass = class;
	found = 0;
	for (; *endofclass; endofclass++) /* google only has alphanumeric class names. TODO: be pedantic and conformic to w3 stds */
		if (!isalnum(endofclass[0]) && (found = 1))
			break;
	if (!found)
		return NULL;
	char * toreturn = malloc(endofclass-class+1);
	strncpy(toreturn, class, endofclass-class);
	toreturn[endofclass-class] = '\0';
	return toreturn;
}
int sc_query_google (char * s, struct sc_cache * c) {
	/*
		remarks:
			* we are using wap.google.com over HTTP and with a user-agent string of a nokia mobile phone, so we get a lite website
			* we determine which class holds a specific value by looking at the css definitions
				- result title: the only class that has definition {color:#1967D2;font-size:14px;line-height:16px}
					+ A links have this class set, but they have a child SPAN element that then holds the text of the title
					+ A href points to a tracking relative link, starting with /url?q=. the q parameter contains the (obv urlencoded) link.
				- result date: class has only one definition, {color:#70757a}, but same definition has the class for the settings A link.
					+ extract those two classes and find the one that is only present on SPAN text elements.
				- result description: once we have the result div, the description is the // span with the appropriate class
					+ the appropriate class is the only one with {word-break:break-word}. note that this class also describes other elements.
				- result div: to get the result div, we need the parent of the parent of the A link of the title.
			* result dates are sometimes relative ("an hour ago") and heavily depend on the client location, based on IP.
				- we won't parse those yet
			* I couldn't find anything with ratings, so we won't parse thouse either yet
			* captcha: google knows that this nokia phone we're pretending to be doesn't support javascript
				- the request limiting captcha must work on a phone without javascript. it is probably loaded inside an iframe, but has
					origin protection, so we can't just solve it client-side. we would have to proxy images and create some sort of a session
					based http request-response based user interface so we can ask the user to complete the captcha. this is not yet
					implemeted and will be hard work.
	*/
	if (!s || !c)
		return -1;
	int rs = 1;
	char * us = malloc(sizeof(char)*strlen(s)*3+1);
	urlencode(us, s);
	char * txtdoc = SC_CAPI(c, NULL, NULL, "http://wap.google.com/search?q=%s", us);
	// fprintf(stdout, "%s\n", txtdoc);
	free(us);
	if (!txtdoc) {
		rs = -2;
		goto rc;
	}
	char * titleclass = sc_find_class(txtdoc, "{color:#1967D2;font-size:14px;line-height:16px}");
	if (!titleclass) {
		SC_LOG(SC_LOG_ERROR, c, "!titleclass");
		rs = -3;
		goto rc;
	}
#define SC_GTXF "/html/body//a[contains(@class, '%s')]" // @class='fuLhoc ZWRArf'"
	char * xpath = malloc(strlen(titleclass)+strlen(SC_GTXF));
	sprintf(xpath, SC_GTXF, titleclass); /* whenever starts with titleclas */
	fprintf(stdout, "%s\n", xpath);
	htmlDocPtr xmldoc = parseHtmlDocument(txtdoc, NULL);
	xmlXPathObjectPtr nodes = findNodes(xmldoc, xpath);
	eachNode(nodes, printLinkNode, NULL);
rc:
	xmlFreeDoc(xmldoc);
	free(txtdoc);
	free(titleclass);
	free(xpath);
	return rs;
}