import std.stdio;
import std.regex;
import std.conv   : to;
import std.file   : readText;
import std.string : splitLines, strip;
import std.array  : split, join;

string get_user_types(string[] lines) {
	bool[string] user_types;
	//writeln(lines);
	foreach (string line; lines) {
		auto m = match(line, regex(r"^(?:class|struct|interface)\s+(\_?[a-z]+\w*)(?:\s*\:\s*(\_?[a-z]+\w*(?:\s*\,\s*)?)*\s*\{?)?", "i"));
		
		if (!m.empty()) {
			auto c = m.captures;
			
			user_types[strip(c[1])] = true;
			
			if (c.length > 2) {
				foreach (string splitter; split(c[2], ",")) {
					user_types[strip(splitter)] = true;
				}
			}
		}
	}
	
	//writeln(user_types.keys);
	
	if (user_types.length > 0) {
		return "r" ~ join(user_types.keys, "|");
	}
	
	return "";
}

void main(string[] args) {
	if (args.length == 1) {
		writeln("Zuwenige Argumente");
		
		return;
	}
	
	const string content = readText(args[1]);
	string[] content_lines = splitLines(content);
	
	string user_types = get_user_types(content_lines);
	if (user_types.length > 0) {
		user_types = r"|" ~ user_types;
	}
	
	string[][] vars;
	
	foreach (uint lnr, string line; content_lines) {
		// is comment?
		auto _m = match(line, regex(r"(?:\/\/+|\/+\*+)"));
		
		if (!_m.empty()) continue;
		
		auto m = match(line, regex(r"((?:u?(?:long|int|short|byte|cent)|(?:(?:i|c)?(?:real|double|float))|bool|(?:w|d)?char|string|Object" ~ user_types ~ r")(?:\s*\[.*?\]\s*)?)\s+(\_?[a-z]+[\-_\w]*?)(\s*\,\s*.+?)?\s*\;", "i"));
		
		if (!m.empty()) {
			auto c = m.captures;
			
			//writeln(c);
			
			string hit = strip(c[2]);
			
			vars ~= [to!(string)(lnr + 1), c[1], hit];
			
			if (c.length > 3) {
				string[] splitter = split(c[3], ",");
				
				foreach (s; splitter) {
					auto m2 = match(s, regex(r"^\s*\_?[a-z]+[\-_\w]*?\s*$", "i"));
					
					if (!m2.empty()) {
						//writeln(m2.captures);
						hit = strip(m2.captures.hit);
						
						vars ~= [to!(string)(lnr + 1), c[1], hit];
					}
				}
			}
		}
	}
	
	//writeln(content);
	writeln("All variables that were not directly initialized: ");
	
	foreach (string[] var; vars) {
		writefln("Variable \"%s\" of Type \"%s\" on line %s", var[2], var[1], var[0]);
	}
	
	bool[string] init;
	
	foreach (string line; splitLines(content)) {
		//writeln(line);
		foreach (string[] var; vars) {
			// is comment?
			auto _m = match(line, regex(r"(?:\/\/+|\/+\*+)"));
			
			if (!_m.empty()) continue;
			
			/* Wird der Variable etwas zugewiesen? */
			auto m  = match(line, regex(r"(?:\*|this\.|super\.|\_?[a-z]+[\-_\w]*?\.)?" ~ var[2] ~ r"(?:\[.*?\])?\s*(?:~\s*)?=\s*(?:.+?|\[.*?\])\s*\;"));
			/* Wird die Variable per Referenz "befüllt"? */
			auto m2 = match(line, regex(r"\&(?:this\.|super\.|\_?[a-z]+[\-_\w]*?\.)?" ~ var[2]));
			/* Wird mit der Variable gerechnet, einer anderen zugewiesen oder eine andere Operation durchgeführt? */
			auto m3 = match(line, regex(r"\_?[a-z]+[\-_\w]*(?:\[.*?\])?\s*(?:~\s*)?=\s*(?:.*?)" ~ var[2]));
			
			if (!m.empty || !m2.empty() || !m3.empty()) {
				init[var[2]] = true;
			}
		}
	}
	
	writeln("\nUnused variables: ");
	
	uint total = 0;
	foreach (string[] var; vars) {
		if (var[2] !in init) {
			writefln("Variable \"%s\" of Type \"%s\" on line %s is unused.", var[2], var[1], var[0]);
			
			++total;
		}
	}
	
	writefln("%d unused variables.", total);
}