"""PayPal 流程：从 Stripe 跳转 PayPal 后，识别落地页类型并强制走"创建账号"路径。

落地页可能是：
  A. /checkoutweb/  —— 直接是 Guest 注册+付款合表（最理想）
  B. 登录页 with #email 单输入框，下方有"Create Account / Sign Up / 注册"链接
  C. 登录页 with #email + #password 双输入框，下方有"Create Account"按钮（你描述的死锁场景：之前点上方 Next 被当成登录）

对策：
  - 不在 B/C 上点上方 Next；先尝试点"创建账号"链接/按钮；
  - 点击后等待跳到 /checkoutweb/ 再走 Guest 表单；
  - 如果点不动，再降级填邮箱点 Next（保留旧行为兜底）。
"""
from __future__ import annotations

import re
import time
from typing import Callable


CREATE_ACCOUNT_PATTERNS = [
    r"create\s+(?:an?\s+)?account",
    r"sign\s*up",
    r"open\s+(?:an?\s+)?account",
    r"pay\s+with\s+(?:debit|credit)\s+card",
    r"pay\s+with\s+card",
    r"continue\s+as\s+guest",
    r"guest\s+checkout",
    r"创建(?:新)?账[户号]",
    r"注册(?:新)?账[户号]",
    r"新建账[户号]",
    r"以游客身份继续",
]
CREATE_ACCOUNT_RE = re.compile("|".join(CREATE_ACCOUNT_PATTERNS), re.I)

LOGIN_TEXT_PATTERNS = [r"\blog\s*in\b", r"\bsign\s*in\b", r"登录"]
LOGIN_RE = re.compile("|".join(LOGIN_TEXT_PATTERNS), re.I)


def _now_ms() -> int:
    return int(time.time() * 1000)


def detect_landing_state(page, log: Callable[[str], None]) -> dict:
    """返回 { kind: 'checkoutweb'|'create_with_c2p'|'login_email_only'|'login_email_password'|'unknown',
              email_count, password_count, has_c2p, url }"""
    url = page.url or ""
    if "/checkoutweb/" in url:
        log(f"[paypal:detect] 已在 /checkoutweb/ url={url}")
        return {"kind": "checkoutweb", "email_count": 0, "password_count": 0, "has_c2p": False, "url": url}

    try:
        info = page.evaluate(
            r"""() => {
                const visible = (el) => {
                    if (!el) return false;
                    const s = window.getComputedStyle(el);
                    if (s.display === 'none' || s.visibility === 'hidden') return false;
                    const r = el.getBoundingClientRect();
                    return r.width > 0 && r.height > 0;
                };
                const emails = Array.from(document.querySelectorAll(
                    'input#email, input[name="email"], input[type="email"], input[autocomplete="username"]'
                )).filter(visible);
                const passwords = Array.from(document.querySelectorAll(
                    'input#password, input[name="password"], input[type="password"], input[autocomplete="current-password"]'
                )).filter(visible);
                const bodyText = (document.body && document.body.innerText || '').replace(/\s+/g, ' ').slice(0, 800);
                // 检测 "Continue to Payment" 中间页特征
                const hasC2P = Array.from(document.querySelectorAll(
                    'button, input[type="submit"], [role="button"]'
                )).filter(visible).some((el) => {
                    const t = (el.innerText || el.getAttribute('aria-label') || '').trim();
                    return /continue\s+to\s+payment|continue\s+to\s+pay|继续(?:到)?(?:支付|付款)|前往(?:支付|付款)/i.test(t);
                });
                const hasCreateAccount = /create\s+(?:a\s+)?paypal\s+account|create\s+(?:an?\s+)?account/i.test(bodyText);
                return {
                    emailCount: emails.length,
                    passwordCount: passwords.length,
                    hasC2P: hasC2P,
                    hasCreateAccount: hasCreateAccount,
                    bodyText: bodyText,
                };
            }"""
        ) or {}
    except Exception as exc:
        log(f"[paypal:detect] page.evaluate 异常: {exc!r}")
        info = {}

    email_count = int(info.get("emailCount") or 0)
    password_count = int(info.get("passwordCount") or 0)
    has_c2p = bool(info.get("hasC2P"))
    has_create = bool(info.get("hasCreateAccount"))
    body_preview = info.get("bodyText") or ""
    log(f"[paypal:detect] url={url} email_count={email_count} password_count={password_count} has_c2p={has_c2p} has_create={has_create} body_preview={body_preview[:160]!r}")

    # 优先识别 "Create Account + Continue to Payment" 中间页
    if has_c2p and has_create and password_count == 0:
        return {"kind": "create_with_c2p", "email_count": email_count, "password_count": password_count, "has_c2p": True, "url": url}
    if has_c2p and password_count == 0 and email_count >= 1:
        return {"kind": "create_with_c2p", "email_count": email_count, "password_count": password_count, "has_c2p": True, "url": url}

    if password_count >= 1:
        return {"kind": "login_email_password", "email_count": email_count, "password_count": password_count, "has_c2p": has_c2p, "url": url}
    if email_count >= 1:
        return {"kind": "login_email_only", "email_count": email_count, "password_count": password_count, "has_c2p": has_c2p, "url": url}
    return {"kind": "unknown", "email_count": email_count, "password_count": password_count, "has_c2p": has_c2p, "url": url}


def find_create_account_action(page, log: Callable[[str], None]):
    """优先找精确 selector，再做文本扫描。返回 Locator 或 None。"""
    for sel in (
        'a[data-testid="signUp"]',
        'button[data-testid="signUp"]',
        'a[data-testid="signup"]',
        'button[data-testid="signup"]',
        'a[data-testid="guest-checkout"]',
        'button[data-testid="guest-checkout"]',
        'button[data-testid="signup-button"]',
        'a[href*="signup" i]',
        'a[href*="create" i]',
    ):
        loc = page.locator(sel)
        if loc.count() == 0:
            continue
        try:
            first = loc.first
            if first.is_visible() and first.is_enabled():
                log(f"[paypal:create] 命中 selector={sel}")
                return first
        except Exception:
            continue

    # 文本扫描：只挑 a / button / role=button / role=link
    try:
        candidates = page.locator('a, button, [role="button"], [role="link"], input[type="button"], input[type="submit"]')
        n = candidates.count()
    except Exception as exc:
        log(f"[paypal:create] 扫描候选失败: {exc!r}")
        return None

    matched = []
    for i in range(min(n, 400)):
        el = candidates.nth(i)
        try:
            if not el.is_visible():
                continue
        except Exception:
            continue
        try:
            txt = (el.inner_text(timeout=400) or "").strip()
        except Exception:
            txt = ""
        if not txt:
            try:
                txt = (el.get_attribute("aria-label") or "").strip()
            except Exception:
                txt = ""
        if not txt:
            continue
        if CREATE_ACCOUNT_RE.search(txt) and not LOGIN_RE.search(txt):
            try:
                rect = el.bounding_box()
            except Exception:
                rect = None
            matched.append((i, txt, rect))

    if not matched:
        log('[paypal:create] 未找到任何 "创建账号/Sign Up/Pay with Card" 候选')
        return None

    # 选 y 坐标最大的（页面下方更可能是"创建账号"）
    matched.sort(key=lambda item: ((item[2] or {}).get("y", 0)), reverse=True)
    chosen_idx, chosen_txt, chosen_rect = matched[0]
    log(f"[paypal:create] 选中候选 idx={chosen_idx} text={chosen_txt!r} rect={chosen_rect}")
    return candidates.nth(chosen_idx)


def click_create_account(page, log: Callable[[str], None]) -> bool:
    el = find_create_account_action(page, log)
    if not el:
        return False
    try:
        el.scroll_into_view_if_needed(timeout=2000)
    except Exception:
        pass
    try:
        el.click(timeout=4000)
        log("[paypal:create] 已点击创建账号")
        return True
    except Exception as exc:
        log(f"[paypal:create] click 失败: {exc!r}，尝试 force click")
    try:
        el.click(timeout=4000, force=True)
        log("[paypal:create] force click 成功")
        return True
    except Exception as exc:
        log(f"[paypal:create] force click 也失败: {exc!r}")
    try:
        el.evaluate("el => el.click()")
        log("[paypal:create] JS .click() 成功")
        return True
    except Exception as exc:
        log(f"[paypal:create] JS click 也失败: {exc!r}")
    return False


def wait_for_checkoutweb(page, log: Callable[[str], None], timeout_sec: int = 25) -> bool:
    deadline = time.time() + timeout_sec
    while time.time() < deadline:
        url = page.url or ""
        if "/checkoutweb/" in url:
            log(f"[paypal:create] 已进入 /checkoutweb/ url={url}")
            return True
        time.sleep(0.4)
    log(f"[paypal:create] 等待 /checkoutweb/ 超时 url={page.url}")
    return False


def find_login_next_button(page, log: Callable[[str], None]):
    """优先精确 selector，再 fallback 文本扫描。返回 Locator 或 None。"""
    for sel in (
        'button[data-testid="submit-button"]',
        'button[type="submit"]',
        'button[id*="btnNext" i]',
        'button#btnNext',
    ):
        loc = page.locator(sel)
        if loc.count() == 0:
            continue
        try:
            first = loc.first
            if first.is_visible() and first.is_enabled():
                log(f"[paypal:login] Next 候选命中 selector={sel}")
                return first
        except Exception:
            continue

    # 文本扫描：找 Next/Log In/继续 等位于 PayPal 顶部表单的按钮
    try:
        candidates = page.locator('button, input[type="submit"], [role="button"]')
        n = candidates.count()
    except Exception as exc:
        log(f"[paypal:login] 扫描候选失败: {exc!r}")
        return None

    LOGIN_NEXT_RE = re.compile(r"\bnext\b|\blog\s*in\b|登录|登入|继续|下一步", re.I)
    for i in range(min(n, 200)):
        el = candidates.nth(i)
        try:
            if not el.is_visible() or not el.is_enabled():
                continue
            txt = (el.inner_text(timeout=400) or "").strip()
            aria = el.get_attribute("aria-label") or ""
            blob = f"{txt} {aria}"
        except Exception:
            continue
        if LOGIN_NEXT_RE.search(blob) and not CREATE_ACCOUNT_RE.search(blob):
            log(f"[paypal:login] Next 文本候选 idx={i} text={txt!r}")
            return el
    return None


def click_login_next(page, log: Callable[[str], None]) -> bool:
    el = find_login_next_button(page, log)
    if not el:
        return False
    try:
        el.scroll_into_view_if_needed(timeout=2000)
    except Exception:
        pass
    for action in ("click", "force_click", "js_click"):
        try:
            if action == "click":
                el.click(timeout=4000)
            elif action == "force_click":
                el.click(timeout=4000, force=True)
            else:
                el.evaluate("el => el.click()")
            log(f"[paypal:login] {action} 成功")
            return True
        except Exception as exc:
            log(f"[paypal:login] {action} 失败: {exc!r}")
            continue
    return False


def find_continue_to_payment_button(page, log: Callable[[str], None]):
    """Create Account 后的中间页：输入邮箱 + "Continue to Payment" 按钮。"""
    # 精确 selector
    for sel in (
        'button[data-testid="continueToPayment"]',
        'button[data-testid="continue-to-payment"]',
        'button[name="continueToPayment"]',
        'button[id*="continueToPayment" i]',
        'button[type="submit"]',
    ):
        loc = page.locator(sel)
        if loc.count() == 0:
            continue
        try:
            first = loc.first
            if first.is_visible() and first.is_enabled():
                # 文本必须像 Continue to Payment / 继续 / Next / Pay
                txt = (first.inner_text(timeout=400) or "").strip()
                if not txt or re.search(r"continue|payment|继续|前往|pay\b", txt, re.I):
                    log(f"[paypal:c2p] 命中 selector={sel} text={txt!r}")
                    return first
        except Exception:
            continue

    # 文本扫描
    try:
        candidates = page.locator('button, input[type="submit"], [role="button"]')
        n = candidates.count()
    except Exception as exc:
        log(f"[paypal:c2p] 扫描失败: {exc!r}")
        return None

    pat = re.compile(r"continue\s+to\s+payment|continue\s+to\s+pay|继续(?:到)?(?:支付|付款)|前往(?:支付|付款)", re.I)
    for i in range(min(n, 200)):
        el = candidates.nth(i)
        try:
            if not el.is_visible() or not el.is_enabled():
                continue
            txt = (el.inner_text(timeout=400) or "").strip()
            aria = el.get_attribute("aria-label") or ""
            blob = f"{txt} {aria}"
        except Exception:
            continue
        if pat.search(blob):
            log(f"[paypal:c2p] 文本候选 idx={i} text={txt!r}")
            return el
    return None


def click_continue_to_payment(page, log: Callable[[str], None]) -> bool:
    el = find_continue_to_payment_button(page, log)
    if not el:
        return False
    try:
        el.scroll_into_view_if_needed(timeout=2000)
    except Exception:
        pass
    for action in ("click", "force_click", "js_click"):
        try:
            if action == "click":
                el.click(timeout=4000)
            elif action == "force_click":
                el.click(timeout=4000, force=True)
            else:
                el.evaluate("el => el.click()")
            log(f"[paypal:c2p] {action} 成功")
            return True
        except Exception as exc:
            log(f"[paypal:c2p] {action} 失败: {exc!r}")
            continue
    return False


def handle_create_account_intermediate(
    page, *, fallback_email: str, log: Callable[[str], None]
) -> bool:
    """Create Account 之后的中间页（邮箱 + Continue to Payment）。
    如果识别到这个页，填邮箱并点 Continue to Payment，等到进入 /checkoutweb/。
    """
    page.wait_for_timeout(1500)
    deadline = time.time() + 12
    while time.time() < deadline:
        try:
            info = page.evaluate(
                r"""() => {
                    const visible = (el) => {
                        if (!el) return false;
                        const s = window.getComputedStyle(el);
                        if (s.display === 'none' || s.visibility === 'hidden') return false;
                        const r = el.getBoundingClientRect();
                        return r.width > 0 && r.height > 0;
                    };
                    const emails = Array.from(document.querySelectorAll(
                        'input#email, input[name="email"], input[type="email"]'
                    )).filter(visible);
                    const passwords = Array.from(document.querySelectorAll(
                        'input[type="password"]'
                    )).filter(visible);
                    const c2p = Array.from(document.querySelectorAll(
                        'button, input[type="submit"], [role="button"]'
                    )).filter(visible).some((el) => {
                        const t = (el.innerText || el.getAttribute('aria-label') || '').trim();
                        return /continue\s+to\s+payment|continue\s+to\s+pay|继续(?:到)?(?:支付|付款)|前往(?:支付|付款)/i.test(t);
                    });
                    return {
                        url: location.href,
                        emailCount: emails.length,
                        passwordCount: passwords.length,
                        hasContinueToPayment: c2p,
                    };
                }"""
            ) or {}
        except Exception as exc:
            log(f"[paypal:c2p] 探测异常: {exc!r}")
            info = {}

        url = info.get("url") or page.url or ""
        if "/checkoutweb/" in url:
            log(f"[paypal:c2p] 已进入 /checkoutweb/ url={url}")
            return True

        # 中间页特征：有 email 框 + Continue to Payment 按钮（且没有 password 框）
        if info.get("emailCount", 0) >= 1 and info.get("hasContinueToPayment") and info.get("passwordCount", 0) == 0:
            log(f'[paypal:c2p] 命中 "输入邮箱 + Continue to Payment" 中间页 url={url}')
            try:
                page.locator('input#email, input[name="email"], input[type="email"]').first.fill(fallback_email)
                log(f"[paypal:c2p] 填邮箱 {fallback_email}")
            except Exception as exc:
                log(f"[paypal:c2p] 填邮箱失败: {exc!r}")
            page.wait_for_timeout(400)
            click_continue_to_payment(page, log)
            # 等待进 /checkoutweb/
            inner_deadline = time.time() + 15
            while time.time() < inner_deadline:
                if "/checkoutweb/" in (page.url or ""):
                    log(f"[paypal:c2p] Continue to Payment 后已进 /checkoutweb/ url={page.url}")
                    return True
                page.wait_for_timeout(400)
            log(f"[paypal:c2p] 点了 Continue to Payment 但未进 /checkoutweb/ url={page.url}")
            break

        time.sleep(0.5)
    return False


def ensure_checkoutweb(
    page,
    *,
    fallback_email: str,
    log: Callable[[str], None],
    on_stage: Callable[[str], None] | None = None,
) -> str:
    """到 /checkoutweb/ 表单页。返回 'login' / 'create' / 'create_c2p' / 'already' / 'unknown'。

    策略：
      1. 已在 /checkoutweb/ → done
      2. email-only 登录页 → 先填 email + 点 Login Next
         - 进 /checkoutweb/ → 'login' 成功
         - 仍卡 / 冒出 password 框 → 走 Create Account
      3. 双输入框（已要求密码）→ 直接 Create Account
      4. Create Account 后若进入"邮箱 + Continue to Payment"中间页，再走一次 → 'create_c2p'
    """
    def stage(name: str):
        log(f"[stage:paypal] {name}")
        if on_stage:
            try:
                on_stage(name)
            except Exception:
                pass

    def should_try_login_next_first(state: dict) -> bool:
        kind = state.get("kind") or ""
        url = (state.get("url") or "").lower()
        # 有 Continue to Payment 特征的页面不走 Login Next，走中间页处理
        if state.get("has_c2p"):
            return False
        # /pay 页面无论单/双输入框，都先尝试填 email + Next
        if "paypal.com/pay" in url and int(state.get("email_count") or 0) >= 1:
            return True
        if kind == "login_email_only":
            return True
        return False

    page.wait_for_load_state("domcontentloaded", timeout=30000)
    page.wait_for_timeout(1500)

    state = detect_landing_state(page, log)
    if state["kind"] == "checkoutweb":
        stage("PayPal 已直达 /checkoutweb/")
        return "already"

    # 优先处理 "Create Account + Continue to Payment" 中间页
    if state.get("kind") == "create_with_c2p" or state.get("has_c2p"):
        stage("PayPal 落地为 Create Account + Continue to Payment 中间页")
        if handle_create_account_intermediate(page, fallback_email=fallback_email, log=log):
            stage("通过 Continue to Payment 进入 /checkoutweb/")
            return "create_c2p"
        # 中间页处理失败，继续尝试其他路径
        log("[paypal] Continue to Payment 中间页处理失败，尝试其他路径")

    # 路径 A：/pay 或 email-only 落地页 → 先尝试邮箱 + Next
    if should_try_login_next_first(state):
        stage("PayPal /pay 登录页：先尝试 Login Next 路径")
        try:
            page.locator('input#email, input[name="email"], input[type="email"]').first.fill(fallback_email)
            log(f"[paypal:login] 填邮箱 {fallback_email}")
        except Exception as exc:
            log(f"[paypal:login] 填邮箱失败: {exc!r}")

        if click_login_next(page, log):
            deadline = time.time() + 15
            password_seen_count = 0
            while time.time() < deadline:
                page.wait_for_timeout(800)
                cur = detect_landing_state(page, log)
                if cur["kind"] == "checkoutweb":
                    stage("通过 Login Next 进入 /checkoutweb/")
                    return "login"
                # 检测到 C2P 中间页，立刻跳出去处理
                if cur.get("has_c2p") or cur["kind"] == "create_with_c2p":
                    log("[paypal:login] Login Next 后检测到 Continue to Payment 中间页，切到 C2P 处理")
                    break
                if cur["kind"] == "login_email_password":
                    password_seen_count += 1
                    if password_seen_count >= 3:
                        log("[paypal:login] 多次检测到 password 输入框，登录路径不可行，将切到 Create Account")
                        break
                else:
                    password_seen_count = 0
            else:
                log("[paypal:login] 15s 内未进 /checkoutweb/，将切到 Create Account 兜底")
        else:
            log("[paypal:login] 没找到可点的 Login Next，将切到 Create Account")

    state2 = detect_landing_state(page, log)
    if state2["kind"] == "checkoutweb":
        stage("Login Next 之后已进 /checkoutweb/")
        return "login"

    # Login Next 后页面变成了 C2P 中间页，直接处理
    if state2.get("has_c2p") or state2["kind"] == "create_with_c2p":
        stage("Login Next 后进入 Create Account + Continue to Payment 中间页")
        if handle_create_account_intermediate(page, fallback_email=fallback_email, log=log):
            stage("通过 Continue to Payment 进入 /checkoutweb/")
            return "create_c2p"
        log("[paypal] Continue to Payment 中间页处理失败")

    # 路径 B：Create Account（之后可能还有"邮箱 + Continue to Payment"中间页）
    stage(f"PayPal 落地为 {state2['kind']}，尝试点击 Create Account")
    if click_create_account(page, log):
        # 直接进 /checkoutweb/？
        if wait_for_checkoutweb(page, log, timeout_sec=10):
            stage("通过 Create Account 直接进入 /checkoutweb/")
            return "create"
        # 否则尝试处理 Continue to Payment 中间页
        stage("Create Account 后未直接进 /checkoutweb/，处理 Continue to Payment 中间页")
        if handle_create_account_intermediate(page, fallback_email=fallback_email, log=log):
            stage("通过 Create Account → Continue to Payment 进入 /checkoutweb/")
            return "create_c2p"
        # 还有一种情况：URL 没改但表单已切到 Guest 模式
        page.wait_for_timeout(1500)
        state3 = detect_landing_state(page, log)
        if state3["kind"] == "checkoutweb":
            return "create"

    log(f"[paypal] 路径都未进 /checkoutweb/ url={page.url}")
    return "unknown"