// J-K-Flip-Flop component for the LogicSimulator
// Copyright (C) 2022 Sascha Nitsch

// 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 <https://www.gnu.org/licenses/>.

interface JKFlipFlopParam extends BaseComponentParam {
  default?: boolean;
}

// eslint-disable-next-line @typescript-eslint/no-unused-vars
class JKFlipFlop extends BaseComponent {
  private j = false;
  private k = false;
  private CLK = true;
  private oldCLK = true;
  private q = false;
  constructor(simulator: Simulator, id: string, param: JKFlipFlopParam = {}) {
    super(simulator, id, param);
    this.pins.set('j', new TriState(this, -30, -15));
    this.pins.set('k', new TriState(this, -30, 15));
    this.pins.set('clk', new TriState(this, -30, 0));
    this.pins.set('q', new TriState(this, 30, -15));
    this.pins.set('notq', new TriState(this, 30, 15));
    if (param.default) this.q = param.default;
    this.getPin('q').setBool(this.q);
    this.getPin('notq').setBool(!this.q);
  }

  setup(canvas: SVGElement) {
    super.doSetup('jkflipflop', canvas);
  }

  io() {
    this.j = this.binary(this.getPin('j').getAndReset(), true);
    this.k = this.binary(this.getPin('k').getAndReset(), true);
    this.CLK = this.binary(this.getPin('clk').getAndReset(), true);
  }

  update(): boolean {
    const oldstate = this.q;
    if (this.oldCLK === false && this.CLK === true) {
      if (this.j === true && this.k === true) {
        this.q = !this.q;
      } else {
        if (this.j === true) {
          this.q = true;
        }
        if (this.k === true) {
          this.q = false;
        }
      }
    }
    this.getPin('q').setBool(this.q);
    this.getPin('notq').setBool(this.q === false);
    this.oldCLK = this.CLK;
    return oldstate !== this.q;
  }
}