const { test } = require("tap");
const fs = require("fs-extra");
const path = require("path");
const sandbox = require("@log4js-node/sandboxed-module");
const zlib = require("zlib");
const util = require("util");

const sleep = util.promisify(setTimeout);
const gunzip = util.promisify(zlib.gunzip);
const EOL = require("os").EOL || "\n";
const log4js = require("../../lib/log4js");

const removeFile = async filename => {
  try {
    await fs.unlink(filename);
  } catch (e) {
    // let's pretend this never happened
  }
};

test("log4js fileAppender", batch => {
  batch.test("with default fileAppender settings", async t => {
    const testFile = path.join(__dirname, "fa-default-test.log");
    const logger = log4js.getLogger("default-settings");
    await removeFile(testFile);

    t.tearDown(async () => {
      await new Promise(resolve => log4js.shutdown(resolve));
      await removeFile(testFile);
    });

    log4js.configure({
      appenders: { file: { type: "file", filename: testFile } },
      categories: { default: { appenders: ["file"], level: "debug" } }
    });

    logger.info("This should be in the file.");

    await sleep(100);
    const fileContents = await fs.readFile(testFile, "utf8");
    t.include(fileContents, `This should be in the file.${EOL}`);
    t.match(
      fileContents,
      /\[\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}] \[INFO] default-settings - /
    );
    t.end();
  });

  batch.test("should flush logs on shutdown", async t => {
    const testFile = path.join(__dirname, "fa-default-test.log");
    await removeFile(testFile);

    log4js.configure({
      appenders: { test: { type: "file", filename: testFile } },
      categories: { default: { appenders: ["test"], level: "trace" } }
    });
    const logger = log4js.getLogger("default-settings");

    logger.info("1");
    logger.info("2");
    logger.info("3");

    await new Promise(resolve => log4js.shutdown(resolve));
    const fileContents = await fs.readFile(testFile, "utf8");
    // 3 lines of output, plus the trailing newline.
    t.equal(fileContents.split(EOL).length, 4);
    t.match(
      fileContents,
      /\[\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}] \[INFO] default-settings - /
    );
    t.end();
  });

  batch.test("with a max file size and no backups", async t => {
    const testFile = path.join(__dirname, "fa-maxFileSize-test.log");
    const logger = log4js.getLogger("max-file-size");

    t.tearDown(async () => {
      await Promise.all([removeFile(testFile), removeFile(`${testFile}.1`)]);
    });
    await Promise.all([removeFile(testFile), removeFile(`${testFile}.1`)]);

    // log file of 100 bytes maximum, no backups
    log4js.configure({
      appenders: {
        file: {
          type: "file",
          filename: testFile,
          maxLogSize: 100,
          backups: 0
        }
      },
      categories: {
        default: { appenders: ["file"], level: "debug" }
      }
    });

    logger.info("This is the first log message.");
    logger.info("This is an intermediate log message.");
    logger.info("This is the second log message.");
    // wait for the file system to catch up
    await sleep(100);
    const fileContents = await fs.readFile(testFile, "utf8");
    t.include(fileContents, "This is the second log message.");
    t.equal(fileContents.indexOf("This is the first log message."), -1);
    const files = await fs.readdir(__dirname);
    const logFiles = files.filter(file =>
      file.includes("fa-maxFileSize-test.log")
    );
    t.equal(logFiles.length, 2, "should be 2 files");
    t.end();
  });

  batch.test("with a max file size in unit mode and no backups", async t => {
    const testFile = path.join(__dirname, "fa-maxFileSize-unit-test.log");
    const logger = log4js.getLogger("max-file-size-unit");

    t.tearDown(async () => {
      await Promise.all([removeFile(testFile), removeFile(`${testFile}.1`)]);
    });
    await Promise.all([removeFile(testFile), removeFile(`${testFile}.1`)]);

    // log file of 1K = 1024 bytes maximum, no backups
    log4js.configure({
      appenders: {
        file: {
          type: "file",
          filename: testFile,
          maxLogSize: "1K",
          backups: 0,
          layout: { type: "messagePassThrough" }
        }
      },
      categories: {
        default: { appenders: ["file"], level: "debug" }
      }
    });
    const maxLine = 22; // 1024 max file size / 47 bytes per line
    for (let i = 0; i < maxLine; i++) {
      logger.info("These are the log messages for the first file."); // 46 bytes per line + '\n'
    }

    logger.info("This is the second log message.");

    // wait for the file system to catch up
    await sleep(100);
    const fileContents = await fs.readFile(testFile, "utf8");
    t.match(fileContents, "This is the second log message.");
    t.notMatch(fileContents, "These are the log messages for the first file.");
    const files = await fs.readdir(__dirname);
    const logFiles = files.filter(file =>
      file.includes("fa-maxFileSize-unit-test.log")
    );
    t.equal(logFiles.length, 2, "should be 2 files");
    t.end();
  });

  batch.test("with a max file size and 2 backups", async t => {
    const testFile = path.join(
      __dirname,
      "fa-maxFileSize-with-backups-test.log"
    );
    const logger = log4js.getLogger("max-file-size-backups");
    await Promise.all([
      removeFile(testFile),
      removeFile(`${testFile}.1`),
      removeFile(`${testFile}.2`)
    ]);

    t.tearDown(async () => {
      await Promise.all([
        removeFile(testFile),
        removeFile(`${testFile}.1`),
        removeFile(`${testFile}.2`)
      ]);
    });

    // log file of 50 bytes maximum, 2 backups
    log4js.configure({
      appenders: {
        file: {
          type: "file",
          filename: testFile,
          maxLogSize: 50,
          backups: 2
        }
      },
      categories: { default: { appenders: ["file"], level: "debug" } }
    });

    logger.info("This is the first log message.");
    logger.info("This is the second log message.");
    logger.info("This is the third log message.");
    logger.info("This is the fourth log message.");
    // give the system a chance to open the stream
    await sleep(200);
    const files = await fs.readdir(__dirname);
    const logFiles = files
      .sort()
      .filter(file => file.includes("fa-maxFileSize-with-backups-test.log"));
    t.equal(logFiles.length, 3);
    t.same(logFiles, [
      "fa-maxFileSize-with-backups-test.log",
      "fa-maxFileSize-with-backups-test.log.1",
      "fa-maxFileSize-with-backups-test.log.2"
    ]);
    let contents = await fs.readFile(path.join(__dirname, logFiles[0]), "utf8");
    t.include(contents, "This is the fourth log message.");
    contents = await fs.readFile(path.join(__dirname, logFiles[1]), "utf8");
    t.include(contents, "This is the third log message.");
    contents = await fs.readFile(path.join(__dirname, logFiles[2]), "utf8");
    t.include(contents, "This is the second log message.");

    t.end();
  });

  batch.test("with a max file size and 2 compressed backups", async t => {
    const testFile = path.join(
      __dirname,
      "fa-maxFileSize-with-backups-compressed-test.log"
    );
    const logger = log4js.getLogger("max-file-size-backups");
    await Promise.all([
      removeFile(testFile),
      removeFile(`${testFile}.1.gz`),
      removeFile(`${testFile}.2.gz`)
    ]);

    t.tearDown(async () => {
      await Promise.all([
        removeFile(testFile),
        removeFile(`${testFile}.1.gz`),
        removeFile(`${testFile}.2.gz`)
      ]);
    });

    // log file of 50 bytes maximum, 2 backups
    log4js.configure({
      appenders: {
        file: {
          type: "file",
          filename: testFile,
          maxLogSize: 50,
          backups: 2,
          compress: true
        }
      },
      categories: { default: { appenders: ["file"], level: "debug" } }
    });
    logger.info("This is the first log message.");
    logger.info("This is the second log message.");
    logger.info("This is the third log message.");
    logger.info("This is the fourth log message.");
    // give the system a chance to open the stream
    await sleep(1000);
    const files = await fs.readdir(__dirname);
    const logFiles = files
      .sort()
      .filter(file =>
        file.includes("fa-maxFileSize-with-backups-compressed-test.log")
      );
    t.equal(logFiles.length, 3, "should be 3 files");
    t.same(logFiles, [
      "fa-maxFileSize-with-backups-compressed-test.log",
      "fa-maxFileSize-with-backups-compressed-test.log.1.gz",
      "fa-maxFileSize-with-backups-compressed-test.log.2.gz"
    ]);
    let contents = await fs.readFile(path.join(__dirname, logFiles[0]), "utf8");
    t.include(contents, "This is the fourth log message.");

    contents = await gunzip(
      await fs.readFile(path.join(__dirname, logFiles[1]))
    );
    t.include(contents.toString("utf8"), "This is the third log message.");
    contents = await gunzip(
      await fs.readFile(path.join(__dirname, logFiles[2]))
    );
    t.include(contents.toString("utf8"), "This is the second log message.");
    t.end();
  });

  batch.test("when underlying stream errors", t => {
    let consoleArgs;
    let errorHandler;

    const RollingFileStream = class {
      end() {
        this.ended = true;
      }

      on(evt, cb) {
        if (evt === "error") {
          this.errored = true;
          errorHandler = cb;
        }
      }

      write() {
        this.written = true;
        return true;
      }
    };
    const fileAppender = sandbox.require("../../lib/appenders/file", {
      globals: {
        console: {
          error(...args) {
            consoleArgs = args;
          }
        }
      },
      requires: {
        streamroller: {
          RollingFileStream
        }
      }
    });

    fileAppender.configure(
      { filename: "test1.log", maxLogSize: 100 },
      { basicLayout() {} }
    );
    errorHandler({ error: "aargh" });

    t.test("should log the error to console.error", assert => {
      assert.ok(consoleArgs);
      assert.equal(
        consoleArgs[0],
        "log4js.fileAppender - Writing to file %s, error happened "
      );
      assert.equal(consoleArgs[1], "test1.log");
      assert.equal(consoleArgs[2].error, "aargh");
      assert.end();
    });
    t.end();
  });

  batch.end();
});