namespace Harness {
    /* eslint-disable prefer-const */
    export let runners: RunnerBase[] = [];
    export let iterations = 1;
    /* eslint-enable prefer-const */

    function runTests(runners: RunnerBase[]) {
        for (let i = iterations; i > 0; i--) {
            for (const runner of runners) {
                runner.initializeTests();
            }
        }
    }

    function tryGetConfig(args: string[]) {
        const prefix = "--config=";
        const configPath = ts.forEach(args, arg => arg.lastIndexOf(prefix, 0) === 0 && arg.substr(prefix.length));
        // strip leading and trailing quotes from the path (necessary on Windows since shell does not do it automatically)
        return configPath && configPath.replace(/(^[\"'])|([\"']$)/g, "");
    }

    export function createRunner(kind: TestRunnerKind): RunnerBase {
        switch (kind) {
            case "conformance":
                return new CompilerBaselineRunner(CompilerTestType.Conformance);
            case "compiler":
                return new CompilerBaselineRunner(CompilerTestType.Regressions);
            case "fourslash":
                return new FourSlashRunner(FourSlash.FourSlashTestType.Native);
            case "fourslash-shims":
                return new FourSlashRunner(FourSlash.FourSlashTestType.Shims);
            case "fourslash-shims-pp":
                return new FourSlashRunner(FourSlash.FourSlashTestType.ShimsWithPreprocess);
            case "fourslash-server":
                return new FourSlashRunner(FourSlash.FourSlashTestType.Server);
            case "project":
                return new project.ProjectRunner();
            case "rwc":
                return new RWC.RWCRunner();
            case "test262":
                return new Test262BaselineRunner();
            case "user":
                return new UserCodeRunner();
            case "dt":
                return new DefinitelyTypedRunner();
            case "docker":
                return new DockerfileRunner();
        }
        return ts.Debug.fail(`Unknown runner kind ${kind}`);
    }

    // users can define tests to run in mytest.config that will override cmd line args, otherwise use cmd line args (test.config), otherwise no options

    const mytestconfigFileName = "mytest.config";
    const testconfigFileName = "test.config";

    const customConfig = tryGetConfig(IO.args());
    const testConfigContent =
        customConfig && IO.fileExists(customConfig)
            ? IO.readFile(customConfig)!
            : IO.fileExists(mytestconfigFileName)
                ? IO.readFile(mytestconfigFileName)!
                : IO.fileExists(testconfigFileName) ? IO.readFile(testconfigFileName)! : "";

    export let taskConfigsFolder: string;
    export let workerCount: number;
    export let runUnitTests: boolean | undefined;
    export let stackTraceLimit: number | "full" | undefined;
    export let noColors = false;
    export let keepFailed = false;

    export interface TestConfig {
        light?: boolean;
        taskConfigsFolder?: string;
        listenForWork?: boolean;
        workerCount?: number;
        stackTraceLimit?: number | "full";
        test?: string[];
        runners?: string[];
        runUnitTests?: boolean;
        noColors?: boolean;
        timeout?: number;
        keepFailed?: boolean;
        shardId?: number;
        shards?: number;
    }

    export interface TaskSet {
        runner: TestRunnerKind;
        files: string[];
    }

    export let configOption: string;
    export let globalTimeout: number;
    function handleTestConfig() {
        if (testConfigContent !== "") {
            const testConfig = <TestConfig>JSON.parse(testConfigContent);
            if (testConfig.light) {
                setLightMode(true);
            }
            if (testConfig.timeout) {
                globalTimeout = testConfig.timeout;
            }
            runUnitTests = testConfig.runUnitTests;
            if (testConfig.workerCount) {
                workerCount = +testConfig.workerCount;
            }
            if (testConfig.taskConfigsFolder) {
                taskConfigsFolder = testConfig.taskConfigsFolder;
            }
            if (testConfig.noColors !== undefined) {
                noColors = testConfig.noColors;
            }
            if (testConfig.keepFailed) {
                keepFailed = true;
            }
            if (testConfig.shardId) {
                setShardId(testConfig.shardId);
            }
            if (testConfig.shards) {
                setShards(testConfig.shards);
            }

            if (testConfig.stackTraceLimit === "full") {
                (<any>Error).stackTraceLimit = Infinity;
                stackTraceLimit = testConfig.stackTraceLimit;
            }
            else if ((+testConfig.stackTraceLimit! | 0) > 0) {
                (<any>Error).stackTraceLimit = +testConfig.stackTraceLimit! | 0;
                stackTraceLimit = +testConfig.stackTraceLimit! | 0;
            }
            if (testConfig.listenForWork) {
                return true;
            }

            const runnerConfig = testConfig.runners || testConfig.test;
            if (runnerConfig && runnerConfig.length > 0) {
                if (testConfig.runners) {
                    runUnitTests = runnerConfig.indexOf("unittest") !== -1;
                }
                for (const option of runnerConfig) {
                    if (!option) {
                        continue;
                    }

                    if (!configOption) {
                        configOption = option;
                    }
                    else {
                        configOption += "+" + option;
                    }

                    switch (option) {
                        case "compiler":
                            runners.push(new CompilerBaselineRunner(CompilerTestType.Conformance));
                            runners.push(new CompilerBaselineRunner(CompilerTestType.Regressions));
                            break;
                        case "conformance":
                            runners.push(new CompilerBaselineRunner(CompilerTestType.Conformance));
                            break;
                        case "project":
                            runners.push(new project.ProjectRunner());
                            break;
                        case "fourslash":
                            runners.push(new FourSlashRunner(FourSlash.FourSlashTestType.Native));
                            break;
                        case "fourslash-shims":
                            runners.push(new FourSlashRunner(FourSlash.FourSlashTestType.Shims));
                            break;
                        case "fourslash-shims-pp":
                            runners.push(new FourSlashRunner(FourSlash.FourSlashTestType.ShimsWithPreprocess));
                            break;
                        case "fourslash-server":
                            runners.push(new FourSlashRunner(FourSlash.FourSlashTestType.Server));
                            break;
                        case "fourslash-generated":
                            runners.push(new GeneratedFourslashRunner(FourSlash.FourSlashTestType.Native));
                            break;
                        case "rwc":
                            runners.push(new RWC.RWCRunner());
                            break;
                        case "test262":
                            runners.push(new Test262BaselineRunner());
                            break;
                        case "user":
                            runners.push(new UserCodeRunner());
                            break;
                        case "dt":
                            runners.push(new DefinitelyTypedRunner());
                            break;
                        case "docker":
                            runners.push(new DockerfileRunner());
                            break;
                    }
                }
            }
        }

        if (runners.length === 0) {
            // compiler
            runners.push(new CompilerBaselineRunner(CompilerTestType.Conformance));
            runners.push(new CompilerBaselineRunner(CompilerTestType.Regressions));

            runners.push(new project.ProjectRunner());

            // language services
            runners.push(new FourSlashRunner(FourSlash.FourSlashTestType.Native));
            runners.push(new FourSlashRunner(FourSlash.FourSlashTestType.Shims));
            runners.push(new FourSlashRunner(FourSlash.FourSlashTestType.ShimsWithPreprocess));
            runners.push(new FourSlashRunner(FourSlash.FourSlashTestType.Server));
            // runners.push(new GeneratedFourslashRunner());

            // CRON-only tests
            if (process.env.TRAVIS_EVENT_TYPE === "cron") {
                runners.push(new UserCodeRunner());
                runners.push(new DockerfileRunner());
            }
        }
        if (runUnitTests === undefined) {
            runUnitTests = runners.length !== 1; // Don't run unit tests when running only one runner if unit tests were not explicitly asked for
        }
        return false;
    }

    function beginTests() {
        if (ts.Debug.isDebugging) {
            ts.Debug.enableDebugInfo();
        }

        // run tests in en-US by default.
        let savedUILocale: string | undefined;
        beforeEach(() => {
            savedUILocale = ts.getUILocale();
            ts.setUILocale("en-US");
        });
        afterEach(() => ts.setUILocale(savedUILocale));

        runTests(runners);

        if (!runUnitTests) {
            // patch `describe` to skip unit tests
            (global as any).describe = ts.noop;
        }
    }

    export let isWorker: boolean;
    function startTestEnvironment() {
        isWorker = handleTestConfig();
        if (isWorker) {
            return Parallel.Worker.start();
        }
        else if (taskConfigsFolder && workerCount && workerCount > 1) {
            return Parallel.Host.start();
        }
        beginTests();
    }

    startTestEnvironment();
}