// content/paypal-flow.js — PayPal login and approval helper.

console.log('[MultiPage:paypal-flow] Content script loaded on', location.href);

const PAYPAL_FLOW_LISTENER_SENTINEL = 'data-multipage-paypal-flow-listener';

if (document.documentElement.getAttribute(PAYPAL_FLOW_LISTENER_SENTINEL) !== '1') {
  document.documentElement.setAttribute(PAYPAL_FLOW_LISTENER_SENTINEL, '1');

  chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
    if (
      message.type === 'PAYPAL_GET_STATE'
      || message.type === 'PAYPAL_SUBMIT_LOGIN'
      || message.type === 'PAYPAL_DISMISS_PROMPTS'
      || message.type === 'PAYPAL_CLICK_APPROVE'
    ) {
      resetStopState();
      handlePayPalCommand(message).then((result) => {
        sendResponse({ ok: true, ...(result || {}) });
      }).catch((err) => {
        if (isStopError(err)) {
          sendResponse({ stopped: true, error: err.message });
          return;
        }
        sendResponse({ error: err.message });
      });
      return true;
    }
  });
} else {
  console.log('[MultiPage:paypal-flow] 消息监听已存在，跳过重复注册');
}

async function handlePayPalCommand(message) {
  switch (message.type) {
    case 'PAYPAL_GET_STATE':
      return inspectPayPalState();
    case 'PAYPAL_SUBMIT_LOGIN':
      return submitPayPalLogin(message.payload || {});
    case 'PAYPAL_DISMISS_PROMPTS':
      return dismissPayPalPrompts();
    case 'PAYPAL_CLICK_APPROVE':
      return clickPayPalApprove();
    default:
      throw new Error(`paypal-flow.js 不处理消息：${message.type}`);
  }
}

async function waitUntil(predicate, options = {}) {
  const intervalMs = Math.max(50, Math.floor(Number(options.intervalMs) || 250));
  while (true) {
    throwIfStopped();
    const value = await predicate();
    if (value) {
      return value;
    }
    await sleep(intervalMs);
  }
}

async function waitForDocumentComplete() {
  await waitUntil(() => document.readyState === 'complete', { intervalMs: 200 });
  await sleep(1000);
}

function isVisibleElement(el) {
  if (!el) return false;
  const style = window.getComputedStyle(el);
  const rect = el.getBoundingClientRect();
  return style.display !== 'none'
    && style.visibility !== 'hidden'
    && Number(rect.width) > 0
    && Number(rect.height) > 0;
}

function normalizeText(text = '') {
  return String(text || '').replace(/\s+/g, ' ').trim();
}

function getActionText(el) {
  return normalizeText([
    el?.textContent,
    el?.value,
    el?.getAttribute?.('aria-label'),
    el?.getAttribute?.('title'),
    el?.getAttribute?.('placeholder'),
    el?.getAttribute?.('name'),
    el?.id,
  ].filter(Boolean).join(' '));
}

function getVisibleControls(selector) {
  return Array.from(document.querySelectorAll(selector)).filter(isVisibleElement);
}

function isEnabledControl(el) {
  return Boolean(el)
    && !el.disabled
    && el.getAttribute?.('aria-disabled') !== 'true';
}

function findClickableByText(patterns) {
  const normalizedPatterns = (Array.isArray(patterns) ? patterns : [patterns]).filter(Boolean);
  const candidates = getVisibleControls('button, a, [role="button"], input[type="button"], input[type="submit"]');
  return candidates.find((el) => {
    const text = getActionText(el);
    return normalizedPatterns.some((pattern) => pattern.test(text));
  }) || null;
}

function findInputByPatterns(patterns) {
  const inputs = getVisibleControls('input')
    .filter((input) => {
      const type = String(input.getAttribute('type') || input.type || '').trim().toLowerCase();
      return !['hidden', 'checkbox', 'radio', 'submit', 'button', 'file'].includes(type);
    });
  return inputs.find((input) => {
    const text = getActionText(input);
    return patterns.some((pattern) => pattern.test(text));
  }) || null;
}

function findEmailInput() {
  return findInputByPatterns([
    /email|login|user|账号|邮箱/i,
  ]) || getVisibleControls('input[type="email"]').find(isVisibleElement) || null;
}

function findPasswordInput() {
  return findInputByPatterns([
    /password|pass|密码/i,
  ]) || getVisibleControls('input[type="password"]').find(isVisibleElement) || null;
}

function findLoginNextButton() {
  return findClickableByText([
    /next|continue|login|log\s*in|sign\s*in/i,
    /下一步|继续|登录|登入/i,
  ]);
}

function findApproveButton() {
  return findClickableByText([
    /同意并继续|同意|继续|授权|确认并继续/i,
    /agree\s*(?:and)?\s*continue|continue|accept|authorize|agree|pay\s*now/i,
  ]);
}

function findPasskeyPromptButtons() {
  const promptPatterns = [
    /passkey|通行密钥|安全密钥|下次登录|faster|save/i,
  ];
  const bodyText = normalizeText(document.body?.innerText || '');
  const likelyPrompt = promptPatterns.some((pattern) => pattern.test(bodyText));
  if (!likelyPrompt) {
    return [];
  }

  const cancelOrClose = getVisibleControls('button, a, [role="button"]')
    .filter((el) => {
      const text = getActionText(el);
      return /取消|稍后|不保存|不用|关闭|cancel|not now|maybe later|skip|close|x/i.test(text)
        || el.getAttribute?.('aria-label')?.match(/close|关闭/i);
    });

  const iconCloseButtons = getVisibleControls('button, [role="button"]')
    .filter((el) => {
      const text = getActionText(el);
      const rect = el.getBoundingClientRect();
      return (/^×$|^x$/i.test(text) || /close|关闭/i.test(text))
        && rect.width <= 64
        && rect.height <= 64;
    });

  return [...cancelOrClose, ...iconCloseButtons];
}

function hasPasskeyPrompt() {
  return findPasskeyPromptButtons().length > 0;
}

async function submitPayPalLogin(payload = {}) {
  await waitForDocumentComplete();

  const email = normalizeText(payload.email || '');
  const password = String(payload.password || '');
  if (!password) {
    throw new Error('PayPal 密码为空，请先在侧边栏配置。');
  }

  let passwordInput = findPasswordInput();
  const emailInput = findEmailInput();

  if (!passwordInput && emailInput && email) {
    fillInput(emailInput, email);
    const nextButton = findLoginNextButton();
    if (nextButton && isEnabledControl(nextButton)) {
      simulateClick(nextButton);
    }
    passwordInput = await waitUntil(() => findPasswordInput(), { intervalMs: 250 });
  } else if (!passwordInput && emailInput && !email) {
    throw new Error('PayPal 账号为空，请先在侧边栏配置。');
  } else if (emailInput && email && !String(emailInput.value || '').trim()) {
    fillInput(emailInput, email);
  }

  passwordInput = passwordInput || await waitUntil(() => findPasswordInput(), { intervalMs: 250 });
  fillInput(passwordInput, password);
  await sleep(1000);

  const loginButton = await waitUntil(() => {
    const button = findClickableByText([
      /login|log\s*in|sign\s*in|continue/i,
      /登录|登入|继续/i,
    ]);
    return button && isEnabledControl(button) ? button : null;
  }, { intervalMs: 250 });

  simulateClick(loginButton);
  return { submitted: true };
}

async function dismissPayPalPrompts() {
  await waitForDocumentComplete();
  const buttons = findPasskeyPromptButtons();
  let clicked = 0;
  for (const button of buttons) {
    if (!isVisibleElement(button) || !isEnabledControl(button)) {
      continue;
    }
    simulateClick(button);
    clicked += 1;
    await sleep(500);
  }
  return {
    clicked,
    hasPromptAfterClick: hasPasskeyPrompt(),
  };
}

async function clickPayPalApprove() {
  await waitForDocumentComplete();
  await dismissPayPalPrompts().catch(() => ({ clicked: 0 }));

  const button = findApproveButton();
  if (!button || !isEnabledControl(button)) {
    return {
      clicked: false,
      state: inspectPayPalState(),
    };
  }

  simulateClick(button);
  return {
    clicked: true,
    buttonText: getActionText(button),
  };
}

function inspectPayPalState() {
  const emailInput = findEmailInput();
  const passwordInput = findPasswordInput();
  const approveButton = findApproveButton();
  return {
    url: location.href,
    readyState: document.readyState,
    needsLogin: Boolean(emailInput || passwordInput),
    hasEmailInput: Boolean(emailInput),
    hasPasswordInput: Boolean(passwordInput),
    approveReady: Boolean(approveButton && isEnabledControl(approveButton)),
    approveButtonText: approveButton ? getActionText(approveButton) : '',
    hasPasskeyPrompt: hasPasskeyPrompt(),
    bodyTextPreview: normalizeText(document.body?.innerText || '').slice(0, 240),
  };
}