#include <cstdlib>

#include <pugixml.hpp>

#include "XMLParser.h"
#include "Exception.h"
#include "Parser.h"

using namespace std;

XMLParser XMLParser::instance {};
XMLParser::XMLParser() {
	Parser::register_strategy(this);
}

unsigned int XMLParser::heuristic(FileStrategy & f) {
	const string content = f.read();
	int open_backets = 0;
	int close_brackets = 0;
	for (char c : content) {
		if (c == '<') open_backets++;
		if (c == '>') close_brackets++;
	}
	int balance = abs(open_backets - close_brackets);
	int penalty = 1 + balance * 10;
	return (open_backets + close_brackets) / penalty;
}

void XMLParser::parse(FileStrategy & f, Deserializer & d) {
	using namespace pugi;

	const string content = f.read();
	xml_document doc;
	xml_parse_result result = doc.load_string(content.c_str());
	if (!result)
		throw Exception("parsing XML failed");

	xml_node canvas = doc.child("canvas");
	if (!canvas)
		throw Exception("missing <canvas>");
	d.set_canvas({
		.rows = canvas.attribute("rows").as_uint(),
		.columns = canvas.attribute("cols").as_uint(),
	});

	xml_node node_types = canvas.child("nodeTypes");
	if (!node_types)
		throw Exception("missing <nodeTypes>");
	for (xml_node node_type : node_types) {
		d.add_type(
			node_type.attribute("tag").as_string(),
			{
				.red = node_type.attribute("red").as_uint(),
				.green = node_type.attribute("green").as_uint(),
				.blue = node_type.attribute("blue").as_uint(),
			},
			node_type.attribute("weight").as_int()
		);
	}

	xml_node nodes = canvas.child("nodes");
	if (!nodes)
		throw Exception("missing <nodes>");
	for (xml_node node : nodes) {
		d.add_tile(
			node.attribute("x").as_uint(),
			node.attribute("y").as_uint(),
			{
				.type = node.name(),
			}
		);
	}
}