#include <iostream>
#include <sstream>
#include <string>
#include "error.h"
#include "prelude.h"

using namespace std;


Environment prelude;

const AST afterBootstrap=AST(R"RAW(
(do
	(def '. \f \g \x (f (g x)))
	(def 'flip \f \a \b (f b a))
	(def 'id \x x)
	(def 'const \x \y x)
	(def 'print (. putstr repr)))
)RAW");

static AST dofunction(const AST&);

const AST doNative=AST::makeNative(dofunction);

static AST dofunction(const AST&){
	return doNative;
}

class PreludeInit{
public:
	PreludeInit(Environment &intoEnv){
		intoEnv.define("repr",AST::makeNative([](const AST &ast) -> AST {
			stringstream ss;
			ss<<ast;
			String res=ss.str();
			return AST::makeString(res);
		}));

		intoEnv.define("putstr",AST::makeNative([](const AST &ast) -> AST {
			if(ast.type!=AST::Type::string){
				throw TypeError("Argument to 'putstr' is not a String");
			}
			cout<<ast.strval<<endl;
			return AST();
		}));

		intoEnv.define("def",[](Environment &env,const AST &arg1) -> AST {
			return AST::makeNative([&env,arg1](const AST &arg2) -> AST {
				if(arg1.type!=AST::Type::name){
					throw TypeError("First argument to 'def' is not a Name");
				}
				env.define(arg1.nameval,arg2);
				return AST();
			});
		});

		intoEnv.define("do",doNative);

		intoEnv.define("unquote",AST::makeNative([](const AST &ast) -> AST {
			AST res(ast);
			res.quoted=false;
			return res;
		}));

		intoEnv.define2("+",[](Environment&,const AST &arg1,const AST &arg2) -> AST {
			if(arg1.type!=arg2.type){
				throw TypeError("Unequal types in '+'");
			}
			if(arg1.type==AST::Type::number){
				return AST::makeNumber(arg1.numval+arg2.numval);
			} else if(arg1.type==AST::Type::string){
				return AST::makeString(arg1.strval+arg2.strval);
			} else {
				throw TypeError("Arguments to '+' neither Number nor String");
			}
		});

		intoEnv.run(afterBootstrap);
	}
} preludeInit(prelude);