var async = require("async");
var spawn = require("child_process").spawn;
var SerialPort = require("serialport");
var path = require("path");
var test = require("tape");

const exec = path.join(process.env.IDF_PATH, "components", "esptool_py", "esptool", "esptool.py");
const portString = "/dev/serial/by-id/usb-Silicon_Labs_CP2102_USB_to_UART_Bridge_Controller_SERIAL_ID-if00-port0";

const buildPath = path.join(__dirname, "lora32", "build");

var args = [
	"--chip",
	"esp32",
	"--baud",
	"460800",
	"--before",
	"default_reset",
	"--after",
	"hard_reset",
	"write_flash",
	"-z",
	"--flash_mode",
	"dio",
	"--flash_freq",
	"40m",
	"--flash_size",
	"detect",
	"0x1000",
	path.join(buildPath, "bootloader/bootloader.bin"),
	"0x10000",
	path.join(buildPath, "lora32.bin"),
	"0x8000",
	path.join(buildPath, "partitions_singleapp.bin")
];

function flash(port, cb) {
  console.log("Flashing devices at %s", port);

  var cp = spawn(exec, ["--port", port].concat(args));

  cp.on("exit", function(code) {
    console.log("%s\nexited: %d", port, code);

    cb(code === 0 ? null : new Error("exited non-zero: " + code));
  });
}

function toggleReset(sp) {
  sp.set({
    dtr: false
  }, function() {
    setTimeout(function() {
      sp.set({
        dtr: true
      });
    }, 1000);
  });
}

function serial(port, cb) {
  var to = -1;
  var buf = "";
  var sp = new SerialPort(port, {
    baudRate: 115200
  });

  sp.once("open", function() {
    console.log("port open %s", port);

    sp.on("data", onData);

    toggleReset(sp);
  });

  function done(reason) {
    console.log("%s ready%s", port, reason || "");

    cb(null, sp);
    sp.removeListener("data", onData);
  }

  function onData(chunk) {
    buf += chunk.toString();

    clearTimeout(to);

    to = setTimeout(function() {
      done(" (timeout)");
    }, 3000);

    if(buf.indexOf("set_spread") !== -1) {
      clearTimeout(to);
      done(" (got set_spreadfactor)");
    }
  }
}

async.series([
  function(next) {
    if(process.env.NOFLASH) {

      return next(null);
    }

    async.parallel([
      function(done) {
        flash(portString.replace("SERIAL_ID", "0001"), done);
      }, function(done) {
        flash(portString.replace("SERIAL_ID", "0002"), done);
      }], next);
  },

  function(next) {
    async.parallel({
      dev1: function(done) {
        serial(portString.replace("SERIAL_ID", "0001"), done);
      },
      
      dev2: function(done) {
        serial(portString.replace("SERIAL_ID", "0002"), done);
      }
    }, next);
  }
], function(err, results) {
  var ports = results[1];

  console.log("init done");

  var buf = "";
  var message = "test";

  test.onFinish(function() {
    console.log("Cleaning up");

    ports.dev1.close();
    ports.dev2.close();
  });

  test(function(t) {
    t.plan(1);

    ports.dev1.on("data", function onData(chunk) {
      //process.stdout.write(chunk);

      buf += chunk.toString();

      if(buf.indexOf(`msg: ${message}`) !== -1) {
        ports.dev1.removeListener("data", onData);

        t.pass("got round-trip message!");
      }
    });

    ports.dev2.on("data", function(chunk) {
      //process.stdout.write(chunk);
    });

    ports.dev2.write(`send${message}\n`);
  }, "round-trip message");

  test(function(t) {
    t.plan(2);

    var sf = 9;
    var msg = `sf${sf}\n`;

    testSetSpreadFactor(ports.dev1);
    testSetSpreadFactor(ports.dev2);

    function testSetSpreadFactor(port) {
      var buf = "";

      port.on("data", function onData(c) {
        buf += c.toString();

        if(buf.indexOf(`spreadfactor: ${sf}`) !== -1) {
          t.pass("spreadfactor set");
          port.removeListener("data", onData);
        }
      });

      port.write(msg);
    };
  }, "spreadfactor");

  test(function(t) {
    t.plan(4);

    var i = 0;

    async.doUntil(function(done) {
      var write = ports["dev" + (1 + i % 2)];
      var read = ports["dev" + (1 + (i + 1) % 2)];

      var buf = "";
      var msg = `tick${i}`;

      read.on("data", function onData(c) {
        buf += c.toString();

        if(buf.indexOf(msg) !== -1) {
          t.pass("got message " + i);

          read.removeListener("data", onData);

          done(null);
        }
      });

      write.write(`send${msg}\n`);
    }, function() {
      return ++i > 5;
    })
  }, "exchange");
});