import { Player } from "../../../src/Player";
import { NetscriptFunctions } from "../../../src/NetscriptFunctions";
import { RamCosts, getRamCost, RamCostConstants } from "../../../src/Netscript/RamCostGenerator";
import { Environment } from "../../../src/Netscript/Environment";
import { RunningScript } from "../../../src/Script/RunningScript";
import { Script } from "../../../src/Script/Script";
import { WorkerScript } from "../../../src/Netscript/WorkerScript";
import { calculateRamUsage } from "../../../src/Script/RamCalculations";

describe("Netscript RAM Calculation/Generation Tests", function () {
  Player.sourceFiles[0] = { n: 4, lvl: 3 };
  // For simulating costs of singularity functions.
  const ScriptBaseCost = RamCostConstants.ScriptBaseRamCost;
  const script = new Script();
  /** Creates a RunningScript object which calculates static ram usage */
  function createRunningScript(code: string) {
    script.code = code;
    script.updateRamUsage([]);
    const runningScript = new RunningScript(script);
    return runningScript;
  }

  type potentiallyAsyncFunction = (arg?: unknown) => { catch?: potentiallyAsyncFunction };
  /** Runs a Netscript function and properly catches an error even if it returns promise. */
  function tryFunction(fn: potentiallyAsyncFunction) {
    try {
      fn()?.catch?.(() => undefined);
    } catch {}
  }

  let runningScript = createRunningScript("");
  //Since it is expensive to create a workerscript and wrap the ns API, this is done once
  const workerScript = {
    args: [] as string[],
    code: "",
    delay: null,
    dynamicLoadedFns: {},
    dynamicRamUsage: RamCostConstants.ScriptBaseRamCost,
    env: new Environment(),
    ramUsage: runningScript.ramUsage,
    scriptRef: runningScript,
  };
  const ns = NetscriptFunctions(workerScript as WorkerScript);

  /**
   * Tests that:
   *      1. A function has non-zero RAM cost, or zero if it is flagged as zero cost.
   *      2. Running the function properly updates the MockWorkerScript's dynamic RAM calculation
   *      3. Running multiple calls of the function does not result in additional RAM cost
   * @param {string[]} fnDesc - describes the name of the function being tested,
   *                            including the namespace(s). e.g. ["gang", "getMemberNames"]
   */
  function testDynamicRamCost(fnDesc: string[], zero: boolean = false) {
    const expected = getRamCost(...fnDesc);
    zero ? expect(expected).toEqual(0) : expect(expected).toBeGreaterThan(0);
  }

  function dynamicCheck(fnPath: string[], expectedRamCost: number) {
    const code = `${fnPath.join(".")}();\n`.repeat(3);
    const fnName = fnPath[fnPath.length - 1];

    // update our existing WorkerScript
    runningScript = createRunningScript(code);
    workerScript.code = code;
    workerScript.scriptRef = runningScript;
    workerScript.ramUsage = workerScript.scriptRef.ramUsage;
    workerScript.dynamicRamUsage = ScriptBaseCost;
    workerScript.env = new Environment();
    workerScript.dynamicLoadedFns = {};
    workerScript.env.vars = ns;

    // Run the function through the workerscript's args
    const fn = fnPath.reduce((prev, curr) => prev[curr], ns as any);

    if (typeof fn === "function") {
      tryFunction(fn);
      tryFunction(fn);
      tryFunction(fn);
    } else {
      throw new Error(`Invalid function specified: [${fnPath.toString()}]`);
    }

    expect(workerScript.dynamicLoadedFns).toHaveProperty(fnName);
    expect(workerScript.dynamicRamUsage - ScriptBaseCost).toBeCloseTo(expectedRamCost, 5);
    expect(workerScript.dynamicRamUsage).toBeCloseTo(runningScript.ramUsage, 5);
  }

  function testFunctionExpectZero(fnPath: string[]) {
    const wholeFn = `${fnPath.join(".")}()`;
    describe(wholeFn, () => {
      it("Zero Ram Static Check", () => {
        const ramCost = getRamCost(...fnPath);
        expect(ramCost).toEqual(0);
        const code = wholeFn;
        const staticCost = calculateRamUsage(code, []).cost;
        expect(staticCost).toEqual(ScriptBaseCost);
      });
      it("Zero Ram Dynamic check", () => dynamicCheck(fnPath, 0));
    });
  }

  function testFunctionExpectNonzero(fnPath: string[]) {
    const wholeFn = `${fnPath.join(".")}()`;
    const ramCost = getRamCost(...fnPath);
    describe(wholeFn, () => {
      it("Static Check", () => {
        expect(ramCost).toBeGreaterThan(0);
        const code = wholeFn;
        const staticCost = calculateRamUsage(code, []).cost;
        expect(staticCost).toBeCloseTo(ramCost + ScriptBaseCost, 5);
      });
      it("Dynamic Check", () => dynamicCheck(fnPath, ramCost));
    });
  }

  type singularityData = { fnPath: string[]; baseCost: number };
  function testSingularityFunctions(data: singularityData[]) {
    const sf4 = Player.sourceFiles[0];
    data.forEach(({ fnPath, baseCost }) => {
      const wholeFn = `${fnPath.join(".")}()`;
      describe(wholeFn, () => {
        it("SF4.3", () => {
          sf4.lvl = 3;
          const ramCost = getRamCost(...fnPath);
          expect(ramCost).toEqual(baseCost);
          const code = wholeFn;
          const staticCost = calculateRamUsage(code, []).cost;
          expect(staticCost).toBeCloseTo(ramCost + ScriptBaseCost);
          dynamicCheck(fnPath, baseCost);
        });
        it("SF4.2", () => {
          sf4.lvl = 2;
          const ramCost = getRamCost(...fnPath);
          expect(ramCost).toBeCloseTo(baseCost * 4, 5);
          const code = wholeFn;
          const staticCost = calculateRamUsage(code, []).cost;
          expect(staticCost).toBeCloseTo(ramCost + ScriptBaseCost);
          dynamicCheck(fnPath, ramCost);
        });
        it("SF4.1", () => {
          sf4.lvl = 1;
          const ramCost = getRamCost(...fnPath);
          expect(ramCost).toBeCloseTo(baseCost * 16, 5);
          const code = wholeFn;
          const staticCost = calculateRamUsage(code, []).cost;
          expect(staticCost).toBeCloseTo(ramCost + ScriptBaseCost);
          dynamicCheck(fnPath, ramCost);
        });
      });
    });
  }

  type NSLayer = {
    [key: string]: NSLayer | unknown[] | (() => unknown);
  };
  type RamLayer = {
    [key: string]: number | (() => number);
  };
  function testLayer(nsLayer: NSLayer, ramLayer: RamLayer, path: string[]) {
    const zeroCostFunctions = Object.entries(nsLayer)
      .filter(([key, val]) => ramLayer[key] === 0 && typeof val === "function")
      .map(([key]) => [...path, key]);
    zeroCostFunctions.forEach(testFunctionExpectZero);

    const nonzeroCostFunctions = Object.entries(nsLayer)
      .filter(([key, val]) => ramLayer[key] > 0 && typeof val === "function")
      .map(([key]) => [...path, key]);
    nonzeroCostFunctions.forEach(testFunctionExpectNonzero);
  }

  describe("Top level ns functions", function () {
    const nsScope = ns as unknown as NSLayer;
    const ramScope = RamCosts as unknown as RamLayer;
    testLayer(nsScope, ramScope, []);
  });

  describe("TIX API (stock) functions", function () {
    const nsScope = ns.stock as unknown as NSLayer;
    const ramScope = RamCosts.stock as unknown as RamLayer;
    testLayer(nsScope, ramScope, ["stock"]);
  });

  describe("Bladeburner API (bladeburner) functions", function () {
    const nsScope = ns.bladeburner as unknown as NSLayer;
    const ramScope = RamCosts.bladeburner as unknown as RamLayer;
    testLayer(nsScope, ramScope, ["bladeburner"]);
  });

  describe("Gang API (gang) functions", function () {
    const nsScope = ns.gang as unknown as NSLayer;
    const ramScope = RamCosts.gang as unknown as RamLayer;
    testLayer(nsScope, ramScope, ["gang"]);
  });

  describe("Coding Contract API (codingcontract) functions", function () {
    const nsScope = ns.codingcontract as unknown as NSLayer;
    const ramScope = RamCosts.codingcontract as unknown as RamLayer;
    testLayer(nsScope, ramScope, ["codingcontract"]);
  });

  describe("Sleeve API (sleeve) functions", function () {
    const nsScope = ns.sleeve as unknown as NSLayer;
    const ramScope = RamCosts.sleeve as unknown as RamLayer;
    testLayer(nsScope, ramScope, ["sleeve"]);
  });

  //Singularity functions are tested in a different way because they also check SF4 level effect
  describe("ns.singularity functions", function () {
    const singularityFunctions = Object.entries(RamCosts.singularity).map(([key, val]) => {
      return {
        fnPath: ["singularity", key],
        baseCost: (val as () => number)(),
      };
    });
    testSingularityFunctions(singularityFunctions);
  });
});