/*
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#include "Gate.h"

int Object::object_id_counter = 0; // initialise static object counter FIXME: do it somehwere else?

Gate::Gate(GATE_TYPE type, int x, int y, int width, int height, int loaded_id)
{
	set_object_type(Object::GATE);
	this->gate_type = type;
	this->input_gate1 = nullptr;
	this->input_gate2 = nullptr;
	this->input_gate3 = nullptr;
	//this->output_gate = nullptr;

	/* special handing of id - if the gate is loaded from file the loaded_id will be set and we use that */
	if (loaded_id != -1)
		this->id = loaded_id;
	else
		this->id = Object::object_id_counter++; // increment counter after assigning
	this->x = x;
	this->y = y;
	this->w = width;
	this->h = height;
}

Gate::~Gate() {}


void
Gate::remove_input_object(int id)
{
	if (input_gate1)
	{
		if (input_gate1->get_id() == id)
			input_gate1 = nullptr;
	}

	if (input_gate2)
	{
		if (input_gate2->get_id() == id)
			input_gate2 = nullptr;
	}

	if (input_gate3)
	{
		if (input_gate3->get_id() == id)
			input_gate3 = nullptr;
	}

}

void Gate::update_state()
{
	switch (this->gate_type)
	{
		case INPUT:
		{
			/* we're a simple input, do nothing */
			break;
		}

		case PULSE:
		{
			if (output_state)
				output_state = false;
			break;
		}

		case OUTPUT:
		{
			if (input_gate1 && input_gate1->get_output_state() == true)
			{
				this->output_state = true;
			}
			else
			{
				this->output_state = false;
			}
			break;
		}

		case AND:
		{
			if (!input_gate1 || !input_gate2) {this->output_state = false; return; }
			output_state = input_gate1->get_output_state() & input_gate2->get_output_state();
			break;
		}


		case OR:
		{
			if (!input_gate1 || !input_gate2) {this->output_state = false; return; }
			output_state = input_gate1->get_output_state() | input_gate2->get_output_state();
			break;
		}


		case NOT:
		{
			/* NOT only cares for input 1 */
			if (!input_gate1) {this->output_state = false; return; }
			output_state = !input_gate1->get_output_state();
			break;
		}


		case NAND:
		{
			if (!input_gate1 || !input_gate2) {this->output_state = false; return; }
			output_state = !(input_gate1->get_output_state() & input_gate2->get_output_state());
			break;
		}

		case NAND3:
		{
			if (!input_gate1 || !input_gate2 || !input_gate3) { output_state = false; return; }
			output_state = !(input_gate1->get_output_state() && input_gate2->get_output_state() && input_gate3->get_output_state());
			break;
		}

		case NOR:
		{
			if (!input_gate1 || !input_gate2) {this->output_state = false; return; }
			output_state = !(input_gate1->get_output_state() | input_gate2->get_output_state());
			break;
		}


		case XOR:
		{
			if (!input_gate1 || !input_gate2) {this->output_state = false; return; }
			output_state = input_gate1->get_output_state() ^ input_gate2->get_output_state();
			break;
		}


		case XNOR:
		{
			if (!input_gate1 || !input_gate2) {this->output_state = false; return; }
			output_state = !(input_gate1->get_output_state() ^ input_gate2->get_output_state());
			break;
		}

		default:
			break;
	}
}

std::string
Gate::get_output_type_text()
{
	std::string out;
	switch (this->gate_type)
	{
		case INPUT:
		{
			return "INPUT";
		}
		case OUTPUT:
		{
			return "OUTPUT";
		}
		case AND:
		{
			return "AND";
		}
		case OR:
		{
			return "OR";
		}
		case NOT:
		{
			return "NOT";
		}
		case NAND:
		{
			return "NAND";
		}
		case NAND3:
		{
			return "3NAND";
		}
		case NOR:
		{
			return "NOR";
		}
		case XOR:
		{
			return "XOR";
		}
		case XNOR:
		{
			return "XNOR";
		}
		default:
		return "?";
	}
}