#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#undef WIN32_LEAN_AND_MEAN

extern "C" {
#include "expat.h"
};

#include "api.h"
#include <stdio.h>
#include <string.h>

#define XML_TYPE		'XM'

#pragma warning(disable: 4244)


class zsRegPrimitive
{
public:
	zsRegPrimitive(const char* name, int type, void* func) { api_add_primitive(name, type, func); }
};


class zsExpat {
public:
	int			depth;
    XML_Parser	parser;
	void		*startfunc;
	void		*endfunc;
	void		*datafunc;
};


void startElement(void *userData, const char *name, const char **attrs)
{
	int k;
	zsExpat *u = (zsExpat*)userData;
    const char **cp = attrs;

	u->depth++;

    if (u->startfunc == 0) {
		for (k = 0; k < u->depth; ++k) putchar(' ');
		printf("<%s>\n", name);
		while (*cp) {
			for (k = 0; k < u->depth; ++k) putchar(' ');
			fprintf(stdout, "%s = %s\n", *cp++, *cp++);
		}
		fflush(stdout);
	}
	else {
		void *p[2];
		p[0] = api_create_integer(u->startfunc, u->depth);
		p[1] = api_create_string(u->startfunc, (char*)name);
		api_call_func(u->startfunc, 2, p);
		while (*cp) {
			p[0] = api_create_string(u->startfunc, (char*)(*cp++));
			p[1] = api_create_string(u->startfunc, (char*)(*cp++));
			api_call_func(u->startfunc, 2, p);
		}
	}
}

void endElement(void *userData, const char *name)
{
	int k;
	zsExpat *u = (zsExpat*)userData;
    if (u->endfunc == 0) {
		for (k = 0; k < u->depth; ++k) putchar(' ');
		fprintf(stdout, "</%s>\n", name);
		fflush(stdout);
	}
	else {
		void *p[1];
		p[0] = api_create_string(u->endfunc, (char*)name);
		api_call_func(u->endfunc, 1, p);
	}
	u->depth--;
}

void charData(void *userData, const char *s, int len)
{
	int k = 0;
	zsExpat *u = (zsExpat*)userData;
    if (u->datafunc == 0) {
		for (k = 0; k < u->depth; ++k) putchar(' ');
		for (k = 0; k < len; ++k) putchar(s[k]);
		fprintf(stdout, "\n");
		fflush(stdout);
	}
	else {
		void *p[1];
		if (len < 32766) {
			char buf[32768];
			memcpy(buf, s, len);
			buf[len] = 0;
			p[0] = api_create_string(u->datafunc, buf);
		}
		else {
			char* buf = new char[len + 1];
			memcpy(buf, s, len);
			buf[len] = 0;
			p[0] = api_create_string(u->datafunc, buf);
			delete[] buf;
		}
		api_call_func(u->datafunc, 1, p);
	}
}    


void input_error(void* caller) { api_runtime_error(caller, "bad arguments");  }


void xml_destroy(void* ptr)
{
	zsExpat *u = (zsExpat*)ptr;
	if (u->parser) XML_ParserFree(u->parser);
	delete u;
}


void* xml_create(void *caller, int nargs, void** args)
{
	zsExpat *u = new zsExpat;
	XML_Parser parser = XML_ParserCreate(0);
    if (!parser) api_runtime_error(caller, "XML_ParserCreate() failed");
    XML_SetUserData(parser, u);
    XML_SetElementHandler(parser, startElement, endElement);
    XML_SetCharacterDataHandler(parser, charData);
	u->parser = parser;
	u->depth = 0;
	u->startfunc = 0;
	u->endfunc = 0;
	u->datafunc = 0;
	return api_create_user(caller, u, 0, xml_destroy, XML_TYPE);
}
static zsRegPrimitive xml0("expat", 0, xml_create);


void* xml_version(void *caller, int nargs, void** args)
{
	return api_create_string(caller, (char*)XML_ExpatVersion());
}
static zsRegPrimitive xml1("version",XML_TYPE, xml_version);


void* xml_callback(void *caller, int nargs, void** args)
{
	if (nargs < 4) input_error(caller);
	zsExpat *u = (zsExpat*)api_get_user(caller, args[0], XML_TYPE);
	u->startfunc = 0;
	u->endfunc = 0;
	u->datafunc = 0;
	const char *s;
	s = api_get_string(caller, args[1]);
	if (strlen(s) > 0) u->startfunc = api_get_func(caller, s);
	s = api_get_string(caller, args[2]);
	if (strlen(s) > 0) u->endfunc = api_get_func(caller, s);
	s = api_get_string(caller, args[3]);
	if (strlen(s) > 0) u->datafunc = api_get_func(caller, s);
	return 0;
}
static zsRegPrimitive xml2("callback", XML_TYPE, xml_callback);


void* xml_parse(void *caller, int nargs, void** args)
{
	if (nargs < 2) input_error(caller);
	zsExpat *u = (zsExpat*)api_get_user(caller, args[0], XML_TYPE);
	const char* s = api_get_string(caller, args[1]);
	int status = XML_Parse(u->parser, s, strlen(s), 0);
	if (status != XML_STATUS_OK) api_runtime_error(caller, XML_ErrorString(XML_GetErrorCode(u->parser)));
    return 0;
}
static zsRegPrimitive xml3("parse", XML_TYPE, xml_parse);