import { BenchmarkFunction } from "./benchmark_types";

export function toFixed(num: number, decimalPlaces = 0): string {

return string.format(`%.${decimalPlaces}f`, num);

}

export function calculatePercentageChange(oldValue: number, newValue: number): number {

return (newValue / oldValue) * 100 - 100;

}

// @ts-ignore

export const isWindows = package.config.startsWith("\\");

export const json: {

decode: (this: void, str: string) => Record<string, unknown> | unknown[];

encode: (this: void, val: any) => string;

} = require("json");

export function readFile(path: string): string {

const [fileHandle] = io.open(path, "rb");

if (!fileHandle) {

throw Error(`Can't open file ${path}`);

}

const fileContent = readAll(fileHandle);

fileHandle.close();

return fileContent;

}

export function readAll(file: LuaFile): string {

const content = file.read(_VERSION === "Lua 5.3" ? "a" : ("*a" as any));

if (content) {

return content as string;

}

throw Error(`Can't readAll for file ${file}`);

}

export function readDir(dir: string): string[] {

const [findHandle] = io.popen(isWindows ? `dir /A-D /B ${dir}` : `find '${dir}' -maxdepth 1 -type f`);

if (!findHandle) {

throw new Error(`Failed to read dir ${dir}`);

}

const findResult = readAll(findHandle);

if (!findHandle.close()) {

throw Error(`readDir popen failed for dir ${dir} see stdout for more information.`);

}

let files = findResult.split("\n");

if (isWindows) {

// on windows we need to append the directory path

// on unix this is done by find automatically

files = files.map(f => `${dir}/${f}`);

} else {

// strip leading "./" on unix

files = files.map(f => (f.startsWith(".") && f[1] === "/" ? f.substr(2) : f));

}

return files.filter(p => p !== "");

}

export function loadBenchmarksFromDirectory(benchmarkDir: string): BenchmarkFunction[] {

const benchmarkFiles = readDir(benchmarkDir);

return benchmarkFiles.map(f => {

// replace slashes with dots

let dotPath = string.gsub(f, "%/", ".")[0];

// remove extension

dotPath = string.gsub(dotPath, ".lua", "")[0];

return require(dotPath).default as BenchmarkFunction;

});

}