let icaptchaXML;
let icaptchactx;

let icaptchas = 2;
let icaptchac = "#ffffff";
let icaptchat = "Secure Code Invalid";
let icaptchag = 0;

// =======================
// 验证码验证
// =======================

function checking_icaptcha() {
  if (window.XMLHttpRequest) {
    icaptchaXML = new XMLHttpRequest();
  } else {
    icaptchaXML = new ActiveXObject("Microsoft.XMLHTTP");
  }

  icaptchaXML.open("POST", "/validate/", false);

  icaptchaXML.setRequestHeader(
    "Content-Type",
    "application/x-www-form-urlencoded",
  );

  icaptchaXML.send(
    "code=" + encodeURIComponent(document.getElementById("secure").value),
  );

  return icaptchaXML.responseText;
}

// =======================
// 登录提交
// =======================

function login_submit() {
  let validate = checking_icaptcha();

  console.log(validate);

  if (validate == "ok=True") {
    $("#submit_login").submit();
  } else {
    alert("Secure Code Invalid");

    document.getElementById("secure").value = "";

    generateCaptcha();

    return false;
  }
}

// =======================
// Load PHP Captcha
// =======================

function loadicaptcha() {
  if (window.XMLHttpRequest) {
    icaptchaXML = new XMLHttpRequest();
  } else {
    icaptchaXML = new ActiveXObject("Microsoft.XMLHTTP");
  }

  icaptchaXML.open("POST", "/icaptcha/", true);

  icaptchaXML.onreadystatechange = readicaptcha;

  icaptchaXML.send();
}

// =======================
// Draw PHP Captcha
// =======================

function readicaptcha() {
  if (icaptchaXML.readyState != 4) {
    return;
  }

  if (icaptchaXML.status != 200) {
    return;
  }

  const captcha = document.getElementById("captchaCanvas");
  if (!captcha) {
    return;
  }

  const container = document.getElementById("icaptcha");
  if (!container) {
    return;
  }

  const ctx = captcha.getContext("2d");

  const width = container.offsetWidth;
  const height = container.offsetHeight;

  captcha.width = width;
  captcha.height = height;

  ctx.clearRect(0, 0, width, height);

  const data = icaptchaXML.responseText;

  const points = new Array(6);
  const count = data.length / 12;

  const c = width / 250;
  const h = height / 100;

  // X / Y offset
  const f = icaptchag - 5;
  const l = icaptchag - 10;

  for (let e = 0; e < count; e++) {
    ctx.beginPath();
    ctx.lineWidth = icaptchas;
    ctx.strokeStyle = icaptchac;

    for (let t = 0; t < 6; t++) {
      points[t] = parseInt(data.substr(e * 12 + t * 2, 2), 16);
    }

    ctx.moveTo((points[0] + f) * c, (points[1] + l) * h);

    ctx.quadraticCurveTo(
      (points[4] + f) * c,
      (points[5] + l) * h,
      (points[2] + f) * c,
      (points[3] + l) * h,
    );

    ctx.stroke();
  }
}

// =======================
// 初始化 Captcha
// =======================

function generateCaptcha() {
  const container = document.getElementById("icaptcha");

  if (!container) {
    return;
  }

  const canvas = document.getElementById("captchaCanvas");

  if (!canvas) {
    return;
  }

  icaptchactx = canvas.getContext("2d");

  loadicaptcha();
}