"use client";

import { useCallback, useEffect, useState } from "react";
import Link from "next/link";
import {
  RefreshCw,
  ImageIcon,
  Type,
  CheckCircle2,
  Mail,
  Link2,
  Shield,
  AlertCircle,
} from "lucide-react";
import {
  apiAdsPublicConfig,
  apiFetchCaptcha,
  apiSubmitAd,
  type AdConfig,
  type AdPaymentOption,
} from "@/lib/api";
import ImageLightbox, { type LightboxItem } from "@/components/markdown/ImageLightbox";
import { AdText } from "@/components/AdText";
import { toast } from "@/lib/toast";
import {
  AD_IMAGE_HEIGHT,
  AD_IMAGE_SIZE_LABEL,
  AD_IMAGE_SIZE_LABEL_2X,
  AD_IMAGE_WIDTH,
  AD_TEXT_COL_WIDTH,
} from "@/lib/ads";

type Kind = "image" | "text";

export default function AdsBuyClient() {
  const [cfg, setCfg] = useState<AdConfig | null>(null);
  const [loadErr, setLoadErr] = useState("");
  const [kind, setKind] = useState<Kind>("image");
  const [email, setEmail] = useState("");
  const [link, setLink] = useState("");
  const [imageURL, setImageURL] = useState("");
  const [title, setTitle] = useState("");
  const [textColor, setTextColor] = useState("#1E293B");
  const [bgColor, setBgColor] = useState("#F1F5F9");
  const [days, setDays] = useState(0);
  const [paymentID, setPaymentID] = useState("");
  const [note, setNote] = useState("");
  const [captchaID, setCaptchaID] = useState("");
  const [captchaImg, setCaptchaImg] = useState("");
  const [captchaCode, setCaptchaCode] = useState("");
  const [busy, setBusy] = useState(false);
  const [done, setDone] = useState(false);
  const [lightbox, setLightbox] = useState<{ items: LightboxItem[]; index: number } | null>(null);

  const refreshCaptcha = useCallback(async () => {
    try {
      const c = await apiFetchCaptcha();
      setCaptchaID(c.id);
      setCaptchaImg(c.image);
      setCaptchaCode("");
    } catch (e) {
      toast(e instanceof Error ? e.message : "验证码加载失败", "error");
    }
  }, []);

  useEffect(() => {
    let alive = true;
    apiAdsPublicConfig()
      .then((c) => {
        if (!alive) return;
        setCfg(c);
        if (c.durations[0]) setDays(c.durations[0].days);
        const pay = c.payments.find((p) => p.enabled && p.qr_url);
        if (pay) setPaymentID(pay.id);
      })
      .catch((e) => {
        if (alive) setLoadErr(e instanceof Error ? e.message : "加载失败");
      });
    void refreshCaptcha();
    return () => {
      alive = false;
    };
  }, [refreshCaptcha]);

  const selectedPay: AdPaymentOption | undefined = cfg?.payments.find((p) => p.id === paymentID);
  const selectedDuration = cfg?.durations.find((d) => d.days === days);
  const canSubmit = !!cfg && cfg.payments.length > 0 && !busy;
  const kindLabel = kind === "image" ? "图片广告" : "文字广告";

  const openLightbox = (src: string, alt = "") => {
    setLightbox({ items: [{ src, alt }], index: 0 });
  };

  const onSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    if (!canSubmit) return;
    setBusy(true);
    try {
      await apiSubmitAd({
        kind,
        contact_email: email,
        link_url: link,
        image_url: kind === "image" ? imageURL : "",
        title: kind === "text" ? title : "",
        text_color: kind === "text" ? textColor : "",
        bg_color: kind === "text" ? bgColor : "",
        duration_days: days,
        payment_id: paymentID,
        buyer_note: note,
        captcha_id: captchaID,
        captcha_code: captchaCode,
      });
      setDone(true);
      toast("提交成功，请完成付款并等待审核", "ok");
    } catch (err) {
      toast(err instanceof Error ? err.message : "提交失败", "error");
      void refreshCaptcha();
    } finally {
      setBusy(false);
    }
  };

  if (loadErr) {
    return (
      <Shell>
        <div className="j13-ads-card p-8 text-center">
          <p className="font-semibold" style={{ color: "var(--ink)" }}>
            {loadErr}
          </p>
          <Link href="/" className="btn btn-line mt-5">
            返回首页
          </Link>
        </div>
      </Shell>
    );
  }

  if (!cfg) {
    return (
      <Shell>
        <div className="j13-ads-card p-6">
          <p className="meta">加载中…</p>
        </div>
      </Shell>
    );
  }

  if (!cfg.enabled) {
    return (
      <Shell>
        <div className="j13-ads-card p-8 text-center">
          <p className="text-lg font-semibold" style={{ color: "var(--ink)" }}>
            自助推广暂未开放
          </p>
          <Link href="/" className="btn btn-primary mt-5">
            返回首页
          </Link>
        </div>
      </Shell>
    );
  }

  if (done) {
    return (
      <Shell>
        <div className="j13-ads-card overflow-hidden text-center">
          <div className="j13-ads-card-head">
            <h1 className="text-[17px] font-bold">申请已提交</h1>
          </div>
          <div className="space-y-4 px-5 py-6">
            <CheckCircle2 size={36} className="mx-auto" style={{ color: "var(--ok)" }} />
            <p className="meta mx-auto max-w-sm text-[13px] leading-relaxed">
              请完成付款，管理员确认后将出现在首页侧栏。
            </p>
            {selectedPay?.qr_url ? (
              <button
                type="button"
                className="mx-auto block cursor-zoom-in"
                onClick={() => openLightbox(selectedPay.qr_url, `${selectedPay.name}收款码`)}
              >
                {/* eslint-disable-next-line @next/next/no-img-element */}
                <img
                  src={selectedPay.qr_url}
                  alt="收款码"
                  className="mx-auto h-40 w-40 rounded-xl border bg-white object-contain p-2"
                  style={{ borderColor: "var(--line)" }}
                />
              </button>
            ) : null}
            <div className="flex justify-center gap-3 pt-1">
              <Link href="/" className="btn btn-primary">
                返回首页
              </Link>
              <button
                type="button"
                className="btn btn-line"
                onClick={() => {
                  setDone(false);
                  void refreshCaptcha();
                }}
              >
                再投一条
              </button>
            </div>
          </div>
        </div>
        {lightbox ? (
          <ImageLightbox
            items={lightbox.items}
            index={lightbox.index}
            onClose={() => setLightbox(null)}
            onIndexChange={(i) => setLightbox((prev) => (prev ? { ...prev, index: i } : prev))}
          />
        ) : null}
      </Shell>
    );
  }

  return (
    <Shell>
      <form onSubmit={onSubmit} className="j13-ads-card overflow-hidden">
        <div className="j13-ads-card-head">
          <h1 className="text-[17px] font-bold tracking-tight">自助购买广告位</h1>
          <p className="text-[12.5px]">
            {kindLabel}
            {selectedDuration ? ` · ${selectedDuration.label}` : ""}
          </p>
        </div>

        <div className="space-y-3 px-4 py-4 sm:px-5 sm:py-5">
          <AdPreview
            kind={kind}
            imageURL={imageURL}
            title={title}
            textColor={textColor}
            bgColor={bgColor}
            onImageClick={() => openLightbox(imageURL, "图片广告预览")}
          />

          <div className="grid grid-cols-2 gap-2">
            <ChipTab active={kind === "image"} onClick={() => setKind("image")}>
              <ImageIcon size={15} /> 图片广告
            </ChipTab>
            <ChipTab active={kind === "text"} onClick={() => setKind("text")}>
              <Type size={15} /> 文字广告
            </ChipTab>
          </div>

          <IconField icon={<Mail size={15} />}>
            <input
              type="email"
              required
              className="j13-ads-input"
              value={email}
              onChange={(e) => setEmail(e.target.value)}
              placeholder="联系邮箱"
              autoComplete="email"
            />
          </IconField>

          <IconField icon={<Link2 size={15} />}>
            <input
              type="url"
              required
              className="j13-ads-input"
              value={link}
              onChange={(e) => setLink(e.target.value)}
              placeholder="广告链接，带 https"
            />
          </IconField>

          {kind === "image" ? (
            <>
              <IconField icon={<ImageIcon size={15} />}>
                <input
                  type="url"
                  required
                  className="j13-ads-input"
                  value={imageURL}
                  onChange={(e) => setImageURL(e.target.value)}
                  placeholder={`图片地址，带 https，尺寸 ${AD_IMAGE_SIZE_LABEL}（高清 ${AD_IMAGE_SIZE_LABEL_2X}）`}
                />
              </IconField>
            </>
          ) : (
            <>
              <IconField icon={<Type size={15} />}>
                <input
                  type="text"
                  required
                  maxLength={24}
                  className="j13-ads-input"
                  value={title}
                  onChange={(e) => setTitle(e.target.value)}
                  placeholder="广告标题，最多 24 字"
                />
              </IconField>
              <div className="grid grid-cols-2 gap-2">
                <label className="j13-ads-field flex items-center gap-2 px-2.5">
                  <input
                    type="color"
                    value={normalizeHex(textColor)}
                    onChange={(e) => setTextColor(e.target.value.toUpperCase())}
                    className="h-7 w-7 shrink-0 cursor-pointer rounded border-0 bg-transparent"
                  />
                  <input
                    className="j13-ads-input !pl-0 font-mono text-[12.5px]"
                    value={textColor}
                    onChange={(e) => setTextColor(e.target.value)}
                    aria-label="文字颜色"
                  />
                </label>
                <label className="j13-ads-field flex items-center gap-2 px-2.5">
                  <input
                    type="color"
                    value={normalizeHex(bgColor)}
                    onChange={(e) => setBgColor(e.target.value.toUpperCase())}
                    className="h-7 w-7 shrink-0 cursor-pointer rounded border-0 bg-transparent"
                  />
                  <input
                    className="j13-ads-input !pl-0 font-mono text-[12.5px]"
                    value={bgColor}
                    onChange={(e) => setBgColor(e.target.value)}
                    aria-label="背景颜色"
                  />
                </label>
              </div>
            </>
          )}

          <div className="grid grid-cols-5 gap-2">
            {cfg.durations.map((d) => {
              const active = days === d.days;
              return (
                <ChipTab key={d.days} active={active} onClick={() => setDays(d.days)} compact>
                  {d.label.replace(/\s/g, "")}
                </ChipTab>
              );
            })}
          </div>

          {cfg.payments.length === 0 ? (
            <div
              className="flex gap-2 rounded-lg border px-3 py-2.5 text-[12.5px] leading-relaxed"
              style={{
                borderColor: "color-mix(in srgb, var(--accent) 28%, var(--line))",
                background: "var(--accent-soft)",
                color: "var(--ink-2)",
              }}
            >
              <AlertCircle size={14} className="mt-0.5 shrink-0" style={{ color: "var(--accent)" }} />
              <span>站长尚未配置收款码。</span>
            </div>
          ) : (
            <>
              <div className="flex flex-wrap gap-2">
                {cfg.payments.map((p) => (
                  <ChipTab key={p.id} active={paymentID === p.id} onClick={() => setPaymentID(p.id)}>
                    {p.name}
                  </ChipTab>
                ))}
              </div>
              {selectedPay?.qr_url ? (
                <button
                  type="button"
                  className="mx-auto block cursor-zoom-in rounded-xl border bg-white p-2.5"
                  style={{ borderColor: "var(--line)" }}
                  onClick={() => openLightbox(selectedPay.qr_url, `${selectedPay.name}收款码`)}
                >
                  {/* eslint-disable-next-line @next/next/no-img-element */}
                  <img
                    src={selectedPay.qr_url}
                    alt={`${selectedPay.name}收款码`}
                    className="h-36 w-36 object-contain"
                  />
                </button>
              ) : null}
              {selectedPay?.hint ? (
                <p className="meta text-center text-[12px] leading-relaxed">{selectedPay.hint}</p>
              ) : null}
            </>
          )}

          <IconField icon={<Mail size={15} />}>
            <input
              className="j13-ads-input"
              maxLength={100}
              value={note}
              onChange={(e) => setNote(e.target.value)}
              placeholder="备注（可选）"
            />
          </IconField>

          <div className="flex items-stretch gap-2">
            <IconField icon={<Shield size={15} />} className="min-w-0 flex-1">
              <input
                required
                className="j13-ads-input uppercase tracking-widest"
                value={captchaCode}
                onChange={(e) => setCaptchaCode(e.target.value)}
                placeholder="图片验证码"
                autoComplete="off"
                maxLength={8}
              />
            </IconField>
            <button
              type="button"
              onClick={() => void refreshCaptcha()}
              className="shrink-0 overflow-hidden rounded-lg border"
              style={{ borderColor: "var(--line)" }}
              title="点击刷新"
              aria-label="刷新验证码"
            >
              {captchaImg ? (
                // eslint-disable-next-line @next/next/no-img-element
                <img src={captchaImg} alt="验证码" width={110} height={42} className="block h-[42px] w-[110px] object-cover" />
              ) : (
                <span className="meta flex h-[42px] w-[110px] items-center justify-center text-[12px]">
                  <RefreshCw size={14} />
                </span>
              )}
            </button>
          </div>

          <button type="submit" className="j13-ads-submit" disabled={!canSubmit}>
            {busy ? "提交中…" : "提交申请"}
          </button>

          <p className="text-center">
            <Link href="/" className="meta text-[12.5px] hover:text-[var(--accent)]">
              返回首页
            </Link>
          </p>
        </div>
      </form>

      {lightbox ? (
        <ImageLightbox
          items={lightbox.items}
          index={lightbox.index}
          onClose={() => setLightbox(null)}
          onIndexChange={(i) => setLightbox((prev) => (prev ? { ...prev, index: i } : prev))}
        />
      ) : null}
    </Shell>
  );
}

function Shell({ children }: { children: React.ReactNode }) {
  return <div className="mx-auto w-full max-w-[560px] px-4 py-6 sm:py-10">{children}</div>;
}

function ChipTab({
  active,
  onClick,
  children,
  compact,
}: {
  active: boolean;
  onClick: () => void;
  children: React.ReactNode;
  compact?: boolean;
}) {
  return (
    <button
      type="button"
      onClick={onClick}
      className={`j13-ads-chip${active ? " is-on" : ""}${compact ? " is-compact" : ""}`}
    >
      {children}
    </button>
  );
}

function IconField({
  icon,
  children,
  className = "",
}: {
  icon: React.ReactNode;
  children: React.ReactNode;
  className?: string;
}) {
  return (
    <label className={`j13-ads-field ${className}`.trim()}>
      <span className="j13-ads-field-ico" aria-hidden>
        {icon}
      </span>
      {children}
    </label>
  );
}

/**
 * 上线预览：复用首页侧栏 .j13-ad-promo 结构与样式，
 * 图片位 248×60、文字位两列网格，尺寸/圆角与侧栏完全一致。
 */
function AdPreview({
  kind,
  imageURL,
  title,
  textColor,
  bgColor,
  onImageClick,
}: {
  kind: Kind;
  imageURL: string;
  title: string;
  textColor: string;
  bgColor: string;
  onImageClick: () => void;
}) {
  const text = title.trim();
  return (
    <div className="text-center">
      <p className="meta mb-2 text-[12px]" style={{ color: "var(--ink-3)" }}>
        上线预览 · 尺寸与首页侧栏一致
      </p>
      <div className="j13-ad-promo">
        {kind === "image" ? (
          <ul className="space-y-2" aria-label="图片广告预览">
            <li>
              {imageURL.startsWith("https://") ? (
                <a
                  href={imageURL}
                  className="j13-ad-image-link"
                  onClick={(e) => {
                    e.preventDefault();
                    onImageClick();
                  }}
                  title="点击放大预览"
                >
                  {/* eslint-disable-next-line @next/next/no-img-element */}
                  <img
                    src={imageURL}
                    alt="图片广告预览"
                    className="j13-ad-image"
                    width={AD_IMAGE_WIDTH}
                    height={AD_IMAGE_HEIGHT}
                  />
                </a>
              ) : (
                <span className="j13-ad-slot j13-ad-slot-image">
                  图片广告位 {AD_IMAGE_SIZE_LABEL}
                </span>
              )}
            </li>
          </ul>
        ) : (
          <ul
            className="j13-ad-text-grid"
            style={{ display: "flex", justifyContent: "center" }}
            aria-label="文字广告预览"
          >
            <li style={{ width: AD_TEXT_COL_WIDTH, minWidth: 0 }}>
              {text.length > 0 ? (
                <AdText title={text} textColor={textColor} bgColor={bgColor} />
              ) : (
                <span className="j13-ad-slot j13-ad-slot-text">文字广告位</span>
              )}
            </li>
          </ul>
        )}
      </div>
    </div>
  );
}

function normalizeHex(v: string): string {
  const s = v.trim();
  if (/^#[0-9A-Fa-f]{6}$/.test(s)) return s;
  if (/^[0-9A-Fa-f]{6}$/.test(s)) return `#${s}`;
  return "#1E293B";
}