/* Tuplr Serialisation
 * Copyright (C) 2008-2009 David Robillard <dave@drobilla.net>
 *
 * Tuplr is free software: you can redistribute it and/or modify it under
 * the terms of the GNU Affero General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or (at your
 * option) any later version.
 *
 * Tuplr is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General
 * Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with Tuplr.  If not, see <http://www.gnu.org/licenses/>.
 */

/** @file
 * @brief Pretty-print AST expressions
 */

#include "tuplr.hpp"

ostream&
operator<<(ostream& out, const AST* ast)
{
	const ALiteral<float>* flit = ast->to<const ALiteral<float>*>();
	if (flit)
		return out << showpoint << flit->val;

	const ALiteral<int32_t>* ilit = ast->to<const ALiteral<int32_t>*>();
	if (ilit)
		return out << ilit->val;

	const ALiteral<bool>* blit = ast->to<const ALiteral<bool>*>();
	if (blit)
		return out << (blit->val ? "#t" : "#f");

	const ASymbol* sym = ast->to<const ASymbol*>();
	if (sym)
		return out << sym->cppstr;

	const AType* type = ast->to<const AType*>();
	if (type) {
		switch (type->kind) {
		case AType::VAR:  return out << "?" << type->id;
		case AType::PRIM: return out << type->at(0);
		case AType::EXPR: break; // will catch Tuple case below
		}
	 }

	const ATuple* tup = ast->to<const ATuple*>();
	if (tup) {
		out << "(";
		for (size_t i = 0; i != tup->size(); ++i)
			out << tup->at(i) << ((i != tup->size() - 1) ? " " : "");
		return out << ")";
	}

	return out << "?";
}

void
pprint_internal(ostream& out, const AST* ast, unsigned indent)
{
	const ATuple* tup = ast->to<const ATuple*>();
	if (tup && tup->size() > 0) {
		const string head = tup->at(0)->str();
		ASymbol* headSym = tup->at(0)->to<ASymbol*>();
		out << "(";
		pprint_internal(out, tup->at(0), indent);
		unsigned child_indent = indent;
		if (tup->size() > 1) {
			out << " ";
			if (headSym && headSym->cppstr == "fn") {
				out << tup->at(1);
				child_indent = indent + 4;
			} else {
				child_indent += head.length() + 1;
				pprint_internal(out, tup->at(1), child_indent);
			}
		}
		for (size_t i = 2; i < tup->size(); ++i) {
			out << endl << string().insert(0, child_indent, ' ');
			pprint_internal(out, tup->at(i), child_indent);
		}
		out << ")";
		if (headSym && headSym->cppstr == "fn")
			out << endl << string().insert(0, indent + 4, ' ');
	} else {
		out << ast;
	}
}

/// Pretty-print @a ast to @a out
void
pprint(ostream& out, const AST* ast)
{
	pprint_internal(out, ast, 0);
	out << endl;
}