broken-neees/NEEES.js

A really broken NEEES emulator that introduces glitches and random bugs on purpose!

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;
var _CPUMemory = _interopRequireDefault(require("./CPUMemory"));
var _CPU = _interopRequireDefault(require("./cpu/CPU"));
var _PPU = _interopRequireDefault(require("./ppu/PPU"));
var _APU = _interopRequireDefault(require("./apu/APU"));
var _Cartridge = _interopRequireDefault(require("./Cartridge"));
var _Controller = _interopRequireDefault(require("./controller/Controller"));
var _mappers = _interopRequireDefault(require("./mappers/mappers"));
var _interrupts = _interopRequireDefault(require("./lib/cpu/interrupts"));
var _saveStates = _interopRequireDefault(require("./saveStates"));
function _interopRequireDefault(e) { return e && e.__esModule ? e : { default: e }; }
function ownKeys(e, r) { var t = Object.keys(e); if (Object.getOwnPropertySymbols) { var o = Object.getOwnPropertySymbols(e); r && (o = o.filter(function (r) { return Object.getOwnPropertyDescriptor(e, r).enumerable; })), t.push.apply(t, o); } return t; }
function _objectSpread(e) { for (var r = 1; r < arguments.length; r++) { var t = null != arguments[r] ? arguments[r] : {}; r % 2 ? ownKeys(Object(t), !0).forEach(function (r) { _defineProperty(e, r, t[r]); }) : Object.getOwnPropertyDescriptors ? Object.defineProperties(e, Object.getOwnPropertyDescriptors(t)) : ownKeys(Object(t)).forEach(function (r) { Object.defineProperty(e, r, Object.getOwnPropertyDescriptor(t, r)); }); } return e; }
function _defineProperty(e, r, t) { return (r = _toPropertyKey(r)) in e ? Object.defineProperty(e, r, { value: t, enumerable: !0, configurable: !0, writable: !0 }) : e[r] = t, e; }
function _toPropertyKey(t) { var i = _toPrimitive(t, "string"); return "symbol" == typeof i ? i : i + ""; }
function _toPrimitive(t, r) { if ("object" != typeof t || !t) return t; var e = t[Symbol.toPrimitive]; if (void 0 !== e) { var i = e.call(t, r || "default"); if ("object" != typeof i) return i; throw new TypeError("@@toPrimitive must return a primitive value."); } return ("string" === r ? String : Number)(t); }
const PPU_STEPS_PER_CPU_CYCLE = 3;
const APU_STEPS_PER_CPU_CYCLE = 0.5;
const TIMEOUT_MS = 3000;
const MAX_STEP_MS = 300;
const BUTTONS = ["BUTTON_A", "BUTTON_B", "BUTTON_SELECT", "BUTTON_START", "BUTTON_UP", "BUTTON_DOWN", "BUTTON_LEFT", "BUTTON_RIGHT"];

/** The NEEES Emulator. */
var _default = exports.default = function _default() {
  let customComponents = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : {};
  return class NEEES {
    constructor() {
      let onFrame = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : () => {};
      let onSample = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : () => {};
      this.customComponents = _objectSpread({}, customComponents);
      const components = _objectSpread({}, customComponents);
      if (!components.CPUMemory) components.CPUMemory = _CPUMemory.default;
      if (!components.CPU) components.CPU = _CPU.default;
      if (!components.PPU) components.PPU = _PPU.default;
      if (!components.APU) components.APU = _APU.default;
      if (!components.Cartridge) components.Cartridge = _Cartridge.default;
      if (!components.Controller) components.Controller = _Controller.default;
      if (!components.mappers) components.mappers = _mappers.default;
      if (!components.omitReset) components.omitReset = false;
      if (!components.unbroken) components.unbroken = false;
      this.components = components;
      this.onFrame = onFrame;
      this.onSample = (sample, pulse1, pulse2, triangle, noise, dmc) => {
        this.sampleCount++;
        onSample(sample, pulse1, pulse2, triangle, noise, dmc);
      };
      let cpuMemory = null;
      try {
        cpuMemory = new this.components.CPUMemory();
      } catch (error) {
        throw new Error("🐒  Failure instantiating new CPUMemory(): " + (error === null || error === void 0 ? void 0 : error.message));
      }
      try {
        this.cpu = new this.components.CPU(cpuMemory);
        if (components.unbroken) this.cpu.unbroken = true;
      } catch (error) {
        throw new Error("🐒  Failure instantiating new CPU(): " + (error === null || error === void 0 ? void 0 : error.message));
      }
      try {
        this.ppu = new this.components.PPU(this.cpu);
      } catch (error) {
        throw new Error("🐒  Failure instantiating new PPU(cpu): " + (error === null || error === void 0 ? void 0 : error.message));
      }
      try {
        this.apu = new this.components.APU(this.cpu);
      } catch (error) {
        throw new Error("🐒  Failure instantiating new APU(cpu): " + (error === null || error === void 0 ? void 0 : error.message));
      }
      this._patchCPUMemory();
      this.sampleCount = 0;
      this.pendingPPUCycles = 0;
      this.pendingAPUCycles = 0;
      this.onScanline = null;
    }

    /** Loads a `rom` as the current cartridge. */
    load(rom) {
      let saveFileBytes = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : [];
      const cartridge = new this.components.Cartridge(rom);
      if (this.components.unbroken) cartridge.unbroken = true;
      const mapper = this.components.mappers.create(this.cpu, this.ppu, cartridge);
      const controller1 = new this.components.Controller(1);
      const controller2 = new this.components.Controller(2);
      controller1.other = controller2;
      controller2.other = controller1;
      const controllers = [controller1, controller2];
      controller1.cpu = this.cpu;
      controller2.cpu = this.cpu;
      try {
        this.cpu.memory.onLoad(this.ppu, this.apu, mapper, controllers);
      } catch (error) {
        throw new Error("🐒  CPU::memory::onLoad(...) failed: " + (error === null || error === void 0 ? void 0 : error.message));
      }
      try {
        var _this$ppu$onLoad, _this$ppu;
        (_this$ppu$onLoad = (_this$ppu = this.ppu).onLoad) === null || _this$ppu$onLoad === void 0 ? void 0 : _this$ppu$onLoad.call(_this$ppu, mapper);
      } catch (error) {
        throw new Error("🐒  PPU::onLoad(...) failed: " + (error === null || error === void 0 ? void 0 : error.message));
      }
      try {
        var _this$ppu$memory, _this$ppu$memory$onLo;
        (_this$ppu$memory = this.ppu.memory) === null || _this$ppu$memory === void 0 ? void 0 : (_this$ppu$memory$onLo = _this$ppu$memory.onLoad) === null || _this$ppu$memory$onLo === void 0 ? void 0 : _this$ppu$memory$onLo.call(_this$ppu$memory, cartridge, mapper);
      } catch (error) {
        throw new Error("🐒  PPU::memory::onLoad(...) failed: " + (error === null || error === void 0 ? void 0 : error.message));
      }
      this.pendingPPUCycles = 0;
      this.pendingAPUCycles = 0;
      this.context = {
        cartridge,
        mapper,
        controllers
      };
      try {
        if (!this.components.omitReset) this.cpu.interrupt(_interrupts.default.RESET);
      } catch (error) {
        throw new Error("🐒  RESET interrupt failed: " + (error === null || error === void 0 ? void 0 : error.message));
      }
      this._setSaveFile(saveFileBytes);
    }

    /** Runs the emulation for a whole video frame. */
    frame() {
      if (!this.context) return;
      let lastTime = Date.now();
      let activeElapsed = 0;
      const currentFrame = this.ppu.frame;
      while (this.ppu.frame === currentFrame) {
        this.step();
        const now = Date.now();
        const gap = now - lastTime;
        lastTime = now;
        activeElapsed += gap < MAX_STEP_MS ? gap : 0; // long gaps = debugging

        if (activeElapsed > TIMEOUT_MS) {
          throw new Error("\uD83D\uDC12  The PPU is taking more than ".concat(TIMEOUT_MS, " ms to generate a single frame. This looks bad!"));
        }
      }
    }

    /** Runs the emulation until the audio system generates `requestedSamples`. */
    samples(requestedSamples) {
      if (!this.context) return;
      let lastTime = Date.now();
      let activeElapsed = 0;
      this.sampleCount = 0;
      while (this.sampleCount < requestedSamples) {
        this.step();
        const now = Date.now();
        const gap = now - lastTime;
        lastTime = now;
        activeElapsed += gap < MAX_STEP_MS ? gap : 0; // long gaps = debugging

        if (activeElapsed > TIMEOUT_MS) {
          throw new Error("\uD83D\uDC12  The APU is taking more than ".concat(TIMEOUT_MS, " ms to generate ").concat(requestedSamples, " samples. This looks bad!"));
        }
      }
    }

    /** Runs the emulation until the next scanline. */
    scanline() {
      let debug = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : false;
      if (!this.context) return;
      let lastTime = Date.now();
      let activeElapsed = 0;
      const currentScanline = this.ppu.scanline;
      while (this.ppu.scanline === currentScanline) {
        this.step();
        const now = Date.now();
        const gap = now - lastTime;
        lastTime = now;
        activeElapsed += gap < MAX_STEP_MS ? gap : 0; // long gaps = debugging

        if (activeElapsed > TIMEOUT_MS) {
          throw new Error("\uD83D\uDC12  The PPU is taking more than ".concat(TIMEOUT_MS, " ms to generate a single scanline. This looks bad!"));
        }
      }
      let oldFrameBuffer;
      if (debug) {
        oldFrameBuffer = new Uint32Array(this.ppu.frameBuffer.length);
        for (let i = 0; i < this.ppu.frameBuffer.length; i++) oldFrameBuffer[i] = this.ppu.frameBuffer[i];
        for (let i = 0; i < 256; i++) this.ppu.plot(i, this.ppu.scanline, 0xff0000ff);
      }
      this.onFrame(this.ppu.frameBuffer);
      if (debug) {
        for (let i = 0; i < this.ppu.frameBuffer.length; i++) this.ppu.frameBuffer[i] = oldFrameBuffer[i];
      }
    }

    /** Executes a step in the emulation (1 CPU instruction). */
    step() {
      let cpuCycles = this.cpu.step();
      cpuCycles = this._clockPPU(cpuCycles);
      this._clockAPU(cpuCycles);
    }

    /** Sets the `button` state of `player` to `isPressed`. */
    setButton(player, button, isPressed) {
      if (!this.context) return;
      if (player !== 1 && player !== 2) throw new Error("Invalid player: ".concat(player, "."));
      this.context.controllers[player - 1].update(button, isPressed);
    }

    /** Sets all buttons of `player` to a non-pressed state. */
    clearButtons(player) {
      if (!this.context) return;
      if (player !== 1 && player !== 2) throw new Error("Invalid player: ".concat(player, "."));
      for (let button of BUTTONS) this.context.controllers[player - 1].update(button, false);
    }

    /** Returns the PRG RAM bytes, or null. */
    getSaveFile() {
      if (!this.context) return;
      const {
        prgRam
      } = this.context.mapper;
      if (!prgRam) return null;
      const bytes = [];
      for (let i = 0; i < prgRam.length; i++) bytes[i] = prgRam[i];
      return bytes;
    }

    /** Returns a snapshot of the current state. */
    getSaveState() {
      if (!this.context) return;
      return _saveStates.default.getSaveState(this);
    }

    /** Restores state from a snapshot. */
    setSaveState(_saveState) {
      if (!this.context) return;
      const saveState = JSON.parse(JSON.stringify(_saveState)); // deep copy

      _saveStates.default.setSaveState(this, saveState);
      this._setSaveFile(saveState.saveFile);
    }
    _clockPPU(cpuCycles) {
      const scanline = this.ppu.scanline;
      let unitCycles = this.pendingPPUCycles + cpuCycles * PPU_STEPS_PER_CPU_CYCLE;
      this.pendingPPUCycles = 0;
      const onIntr = interrupt => {
        const newCPUCycles = this.cpu.interrupt(interrupt);
        cpuCycles += newCPUCycles;
        this.pendingPPUCycles += newCPUCycles * PPU_STEPS_PER_CPU_CYCLE;
      };
      for (let i = 0; i < unitCycles; i++) {
        // <optimization>
        if (this.ppu.cycle > 1 && this.ppu.cycle < 256 || this.ppu.cycle > 260 && this.ppu.cycle < 304 || this.ppu.cycle > 304 && this.ppu.cycle < 340) {
          this.ppu.cycle++;
          continue;
        }
        // </optimization>

        this.ppu.step(this.onFrame, onIntr);
      }
      if (this.ppu.scanline !== scanline && this.onScanline != null) this.onScanline();
      return cpuCycles;
    }
    _clockAPU(cpuCycles) {
      let unitCycles = this.pendingAPUCycles + cpuCycles * APU_STEPS_PER_CPU_CYCLE;
      const onIntr = interrupt => {
        const newCPUCycles = this.cpu.interrupt(interrupt);
        unitCycles += newCPUCycles * APU_STEPS_PER_CPU_CYCLE;
        this.pendingPPUCycles += newCPUCycles * PPU_STEPS_PER_CPU_CYCLE;
      };
      while (unitCycles >= 1) {
        this.apu.step(this.onSample, onIntr);
        unitCycles--;
      }
      this.pendingAPUCycles = unitCycles;
    }
    _setSaveFile(prgRamBytes) {
      const prgRam = this.context.mapper.prgRam;
      if (!prgRam || !prgRamBytes) return;
      for (let i = 0; i < prgRamBytes.length; i++) prgRam[i] = prgRamBytes[i];
    }
    _patchCPUMemory() {
      if (!this.cpu.memory) throw new Error("🐒  CPU::memory not found");
      this._patchCPUMemoryReads();
      this._patchCPUMemoryWrites();
    }
    _patchCPUMemoryReads() {
      const components = this.customComponents;
      const memory = this.cpu.memory;
      const read = memory.read;
      if (!read) throw new Error("🐒  CPU::memory::read(...) not found");
      memory.read = function (address) {
        // PPU registers
        if (!components.PPU || !components.CPUMemory) {
          var _this$ppu$registers$r, _this$ppu$registers, _this$ppu$registers$r2, _this$ppu$registers$r3, _this$ppu$registers2, _this$ppu$registers2$;
          if (address >= 0x2000 && address <= 0x2007 || address === 0x4014) return (_this$ppu$registers$r = (_this$ppu$registers = this.ppu.registers) === null || _this$ppu$registers === void 0 ? void 0 : (_this$ppu$registers$r2 = _this$ppu$registers.read) === null || _this$ppu$registers$r2 === void 0 ? void 0 : _this$ppu$registers$r2.call(_this$ppu$registers, address)) !== null && _this$ppu$registers$r !== void 0 ? _this$ppu$registers$r : 0;else if (address >= 0x2008 && address <= 0x3fff) return (_this$ppu$registers$r3 = (_this$ppu$registers2 = this.ppu.registers) === null || _this$ppu$registers2 === void 0 ? void 0 : (_this$ppu$registers2$ = _this$ppu$registers2.read) === null || _this$ppu$registers2$ === void 0 ? void 0 : _this$ppu$registers2$.call(_this$ppu$registers2, 0x2000 + (address - 0x2008) % 0x0008)) !== null && _this$ppu$registers$r3 !== void 0 ? _this$ppu$registers$r3 : 0;
        }

        // APU registers
        if (!components.APU || !components.CPUMemory) {
          var _this$apu$registers$r, _this$apu$registers, _this$apu$registers$r2;
          if (address >= 0x4000 && address <= 0x4013 || address === 0x4015) return (_this$apu$registers$r = (_this$apu$registers = this.apu.registers) === null || _this$apu$registers === void 0 ? void 0 : (_this$apu$registers$r2 = _this$apu$registers.read) === null || _this$apu$registers$r2 === void 0 ? void 0 : _this$apu$registers$r2.call(_this$apu$registers, address)) !== null && _this$apu$registers$r !== void 0 ? _this$apu$registers$r : 0;
        }

        // Controller ports
        if (!components.Controller || !components.CPUMemory) {
          if (address === 0x4016) return this.controllers[0].onRead();else if (address === 0x4017) return this.controllers[1].onRead();
        }

        // APU and I/O functionality that is normally disabled
        if (address >= 0x4018 && address <= 0x401f) return 0;

        // Cartridge space: PRG ROM, PRG RAM, and mapper registers
        if (!components.mappers || !components.CPUMemory) {
          if (address >= 0x4020 && address <= 0xffff) return this.mapper.cpuRead(address);
        }

        // Original method call
        return read.call(this, address);
      };
    }
    _patchCPUMemoryWrites() {
      const components = this.customComponents;
      const memory = this.cpu.memory;
      const write = memory.write;
      if (!write) throw new Error("🐒  CPU::memory::write(...) not found");
      memory.write = function (address, value) {
        // PPU registers
        if (!components.PPU || !components.CPUMemory) {
          var _this$ppu$registers3, _this$ppu$registers3$, _this$ppu$registers4, _this$ppu$registers4$;
          if (address >= 0x2000 && address <= 0x2007 || address === 0x4014) return (_this$ppu$registers3 = this.ppu.registers) === null || _this$ppu$registers3 === void 0 ? void 0 : (_this$ppu$registers3$ = _this$ppu$registers3.write) === null || _this$ppu$registers3$ === void 0 ? void 0 : _this$ppu$registers3$.call(_this$ppu$registers3, address, value);else if (address >= 0x2008 && address <= 0x3fff) return (_this$ppu$registers4 = this.ppu.registers) === null || _this$ppu$registers4 === void 0 ? void 0 : (_this$ppu$registers4$ = _this$ppu$registers4.write) === null || _this$ppu$registers4$ === void 0 ? void 0 : _this$ppu$registers4$.call(_this$ppu$registers4, 0x2000 + (address - 0x2008) % 0x0008, value);
        }

        // APU registers
        if (!components.APU || !components.CPUMemory) {
          var _this$apu$registers2, _this$apu$registers2$;
          if (address >= 0x4000 && address <= 0x4013 || address === 0x4015 || address === 0x4017) return (_this$apu$registers2 = this.apu.registers) === null || _this$apu$registers2 === void 0 ? void 0 : (_this$apu$registers2$ = _this$apu$registers2.write) === null || _this$apu$registers2$ === void 0 ? void 0 : _this$apu$registers2$.call(_this$apu$registers2, address, value);
        }

        // Controller ports
        if (!components.Controller || !components.CPUMemory) {
          if (address === 0x4016) return this.controllers[0].onWrite(value);
        }

        // APU and I/O functionality that is normally disabled
        if (address >= 0x4018 && address <= 0x401f) return;

        // Cartridge space: PRG ROM, PRG RAM, and mapper registers
        if (!components.mappers || !components.CPUMemory) {
          if (address >= 0x4020 && address <= 0xffff) return this.mapper.cpuWrite(address, value);
        }

        // Original method call
        return write.call(this, address, value);
      };
    }
  };
};