"use client";

import { useState, useEffect } from "react";
import { useParams, useRouter } from "next/navigation";
import Link from "next/link";
import { TopNav } from "@/components/layout/top-nav";
import { AmbientParticles } from "@/components/ui/ambient-particles";
import { useApp } from "@/lib/app-context";
import type { StylePack, StyleRefImage } from "@/lib/types";

export default function StyleDetailPage() {
  const params = useParams<{ id: string }>();
  const router = useRouter();
  const isNew = params.id === "new";
  const {
    stylePacks,
    upsertStylePack,
    deleteStylePack,
    setSessionStyleId,
    assets,
  } = useApp();

  const [pack, setPack] = useState<StylePack | null>(null);

  useEffect(() => {
    if (isNew) {
      const now = Date.now();
      setPack({
        id: `style-${now.toString(36)}`,
        name: "",
        description: "",
        keywords: [],
        source: "custom",
        refImages: [],
        positivePrompt: "",
        negativePrompt: "",
        usageCount: 0,
        createdAt: now,
        updatedAt: now,
      });
    } else {
      const found = stylePacks.find((s) => s.id === params.id);
      if (found) setPack(found);
    }
  }, [params.id, stylePacks, isNew]);

  if (!pack) {
    return (
      <div className="h-screen flex flex-col">
        <TopNav />
        <main className="flex-1 flex items-center justify-center">
          <p className="typo-caption">加载中...</p>
        </main>
      </div>
    );
  }

  const handleSave = () => {
    if (!pack.name.trim()) {
      alert("请填写风格名称");
      return;
    }
    upsertStylePack(pack);
    alert("已保存（占位）");
    if (isNew) router.push(`/styles/${pack.id}`);
  };

  const handleApplyToSession = () => {
    setSessionStyleId(pack.id);
    alert(`已将风格 "${pack.name}" 应用到当前会话（占位）`);
    router.push("/");
  };

  const handleFork = () => {
    const now = Date.now();
    const forked: StylePack = {
      ...pack,
      id: `style-${now.toString(36)}`,
      name: `${pack.name} (副本)`,
      source: "custom",
      forkFromId: pack.id,
      usageCount: 0,
      createdAt: now,
      updatedAt: now,
    };
    upsertStylePack(forked);
    alert("已创建副本（占位）");
    router.push(`/styles/${forked.id}`);
  };

  const handleDelete = () => {
    if (!confirm(`确认删除风格 "${pack.name}"？（占位操作）`)) return;
    deleteStylePack(pack.id);
    router.push("/styles");
  };

  const addRef = () => {
    const id = `ref-${Date.now()}`;
    setPack({
      ...pack,
      refImages: [...pack.refImages, { id, url: "", caption: "占位参考图" }],
    });
  };

  const removeRef = (id: string) => {
    setPack({ ...pack, refImages: pack.refImages.filter((r) => r.id !== id) });
  };

  const addKeyword = (kw: string) => {
    if (!kw || pack.keywords.includes(kw)) return;
    setPack({ ...pack, keywords: [...pack.keywords, kw] });
  };

  const removeKeyword = (kw: string) => {
    setPack({ ...pack, keywords: pack.keywords.filter((k) => k !== kw) });
  };

  // 历史预览（按 prompt 关键词简单匹配）
  const relatedAssets = assets
    .filter((a) =>
      pack.keywords.some((k) => a.prompt.toLowerCase().includes(k.toLowerCase()))
    )
    .slice(0, 6);

  return (
    <div className="h-screen flex flex-col">
      <AmbientParticles count={12} />
      <TopNav />

      <main className="flex-1 overflow-y-auto">
        <div className="max-w-5xl mx-auto px-4 md:px-8 py-6 md:py-8">
          {/* 面包屑 */}
          <div className="flex items-center gap-1.5 text-xs text-[var(--text-secondary)] mb-4">
            <Link href="/styles" className="hover:text-[var(--accent)] cursor-pointer">
              风格库
            </Link>
            <span>/</span>
            <span className="text-[var(--text-primary)]">
              {isNew ? "新建风格" : pack.name || "未命名"}
            </span>
          </div>

          {/* 标题 + 操作 */}
          <div className="flex flex-wrap items-start justify-between gap-4 mb-6">
            <div className="flex-1 min-w-0">
              <div className="flex items-center gap-2 mb-1.5">
                <input
                  value={pack.name}
                  onChange={(e) => setPack({ ...pack, name: e.target.value })}
                  placeholder="风格名称"
                  className="text-2xl font-bold bg-transparent border-none
                             text-[var(--text-primary)] placeholder:text-[var(--text-secondary)]/60
                             focus:outline-none min-w-0 flex-1"
                />
                <span className="phase-chip flex-shrink-0">Phase 1</span>
              </div>
              {pack.forkFromId && (
                <div className="text-xs text-[var(--text-secondary)]">
                  Fork 自：
                  <Link
                    href={`/styles/${pack.forkFromId}`}
                    className="text-[var(--accent)] hover:underline"
                  >
                    {stylePacks.find((s) => s.id === pack.forkFromId)?.name || pack.forkFromId}
                  </Link>
                </div>
              )}
            </div>
            <div className="flex flex-wrap gap-2">
              <button
                onClick={handleApplyToSession}
                className="px-3.5 py-2 text-xs rounded-xl font-medium
                           bg-[var(--accent)] text-[var(--bg-primary)]
                           hover:bg-[var(--accent-hover)]
                           cursor-pointer btn-hover-lift transition-all"
              >
                应用到当前会话
              </button>
              <button
                onClick={handleSave}
                className="px-3.5 py-2 text-xs rounded-xl font-medium
                           border border-[var(--border)] bg-[var(--bg-tertiary)]
                           text-[var(--text-primary)] hover:border-[var(--accent)]/40
                           cursor-pointer btn-hover-lift transition-all"
              >
                保存
              </button>
              {!isNew && (
                <>
                  <button
                    onClick={handleFork}
                    className="px-3.5 py-2 text-xs rounded-xl font-medium
                               border border-[var(--border)] bg-[var(--bg-tertiary)]
                               text-[var(--text-secondary)] hover:text-[var(--text-primary)]
                               cursor-pointer btn-hover-lift transition-all"
                  >
                    复制 / Fork
                  </button>
                  <Link
                    href={`/training/new?type=style&source=${pack.id}`}
                    className="px-3.5 py-2 text-xs rounded-xl font-medium
                               border border-[var(--gold)]/30 bg-[var(--gold)]/8
                               text-[var(--gold)] hover:bg-[var(--gold)]/15
                               cursor-pointer btn-hover-lift transition-all
                               flex items-center gap-1"
                  >
                    训练风格 LoRA
                    <span className="text-[9px]">P2</span>
                  </Link>
                  <button
                    onClick={handleDelete}
                    className="px-3.5 py-2 text-xs rounded-xl font-medium
                               border border-[var(--border)] bg-[var(--bg-tertiary)]
                               text-[var(--hot)]/60 hover:text-[var(--hot)]
                               hover:border-[var(--hot)]/40
                               cursor-pointer btn-hover-lift transition-all"
                  >
                    删除
                  </button>
                </>
              )}
            </div>
          </div>

          <div className="grid grid-cols-1 lg:grid-cols-3 gap-6">
            {/* 左侧：基本信息 + Prompt */}
            <div className="lg:col-span-2 space-y-5">
              {/* 描述 */}
              <section>
                <h2 className="typo-h2 mb-2">风格描述</h2>
                <textarea
                  value={pack.description}
                  onChange={(e) => setPack({ ...pack, description: e.target.value })}
                  placeholder="用一句话描述这个风格的核心特征..."
                  rows={3}
                  className="w-full p-3 rounded-xl bg-[var(--bg-tertiary)] border border-[var(--border)]
                             text-sm text-[var(--text-primary)] placeholder:text-[var(--text-secondary)]
                             focus:outline-none focus:border-[var(--accent)]/50 resize-none"
                />
              </section>

              {/* 关键词 */}
              <section>
                <h2 className="typo-h2 mb-2">关键词标签</h2>
                <div className="flex flex-wrap gap-1.5 mb-2">
                  {pack.keywords.map((k) => (
                    <span
                      key={k}
                      className="flex items-center gap-1 text-xs px-2.5 py-1 rounded-lg
                                 bg-[var(--accent)]/10 text-[var(--accent)] font-medium"
                    >
                      {k}
                      <button
                        onClick={() => removeKeyword(k)}
                        className="hover:text-[var(--hot)] cursor-pointer"
                      >
                        ×
                      </button>
                    </span>
                  ))}
                  <KeywordInput onAdd={addKeyword} />
                </div>
              </section>

              {/* 风格参考集 */}
              <section>
                <div className="flex items-center justify-between mb-2">
                  <h2 className="typo-h2">风格参考集</h2>
                  <button
                    onClick={addRef}
                    className="text-xs px-2.5 py-1 rounded-lg border border-[var(--border)]
                               text-[var(--text-secondary)] hover:text-[var(--accent)]
                               hover:border-[var(--accent)]/40 cursor-pointer transition-all"
                  >
                    + 添加参考图（占位）
                  </button>
                </div>
                <p className="typo-caption mb-3">
                  3-10 张代表该风格核心特征的参考图，可增删替换。
                </p>
                <div className="grid grid-cols-3 md:grid-cols-4 gap-2.5">
                  {pack.refImages.map((ref) => (
                    <RefImageCard
                      key={ref.id}
                      ref_={ref}
                      onRemove={() => removeRef(ref.id)}
                    />
                  ))}
                  {pack.refImages.length === 0 && (
                    <div className="col-span-3 md:col-span-4 py-8 text-center text-xs text-[var(--text-secondary)]
                                    placeholder-card rounded-xl">
                      尚未添加参考图
                    </div>
                  )}
                </div>
              </section>

              {/* Prompt 模板 */}
              <section>
                <h2 className="typo-h2 mb-2">Prompt 模板</h2>
                <div className="space-y-2.5">
                  <div>
                    <div className="typo-micro mb-1" style={{ textTransform: "none" }}>
                      正向 Prompt
                    </div>
                    <textarea
                      value={pack.positivePrompt ?? ""}
                      onChange={(e) => setPack({ ...pack, positivePrompt: e.target.value })}
                      placeholder="描述风格特征的 Prompt 片段，会在生成时前置注入..."
                      rows={2}
                      className="w-full p-2.5 rounded-lg bg-[var(--bg-tertiary)] border border-[var(--border)]
                                 text-xs text-[var(--text-primary)] placeholder:text-[var(--text-secondary)]
                                 focus:outline-none focus:border-[var(--accent)]/50 resize-none font-mono"
                    />
                  </div>
                  <div>
                    <div className="typo-micro mb-1" style={{ textTransform: "none" }}>
                      负向 Prompt
                    </div>
                    <textarea
                      value={pack.negativePrompt ?? ""}
                      onChange={(e) => setPack({ ...pack, negativePrompt: e.target.value })}
                      placeholder="要避免的风格特征..."
                      rows={2}
                      className="w-full p-2.5 rounded-lg bg-[var(--bg-tertiary)] border border-[var(--border)]
                                 text-xs text-[var(--text-primary)] placeholder:text-[var(--text-secondary)]
                                 focus:outline-none focus:border-[var(--accent)]/50 resize-none font-mono"
                    />
                  </div>
                </div>
              </section>

              {/* 历史预览 */}
              <section>
                <h2 className="typo-h2 mb-2">使用该风格生成的图片</h2>
                <p className="typo-caption mb-3">
                  自动从资源库聚合（占位：基于关键词匹配的示意）。
                </p>
                {relatedAssets.length === 0 ? (
                  <div className="py-8 text-center text-xs text-[var(--text-secondary)]
                                  placeholder-card rounded-xl">
                    尚无历史生成
                  </div>
                ) : (
                  <div className="grid grid-cols-3 md:grid-cols-6 gap-2">
                    {relatedAssets.map((a) => (
                      <div
                        key={a.id}
                        className="aspect-square rounded-lg overflow-hidden border border-[var(--border)]"
                      >
                        <div className="w-full h-full bg-[var(--bg-tertiary)] flex items-center justify-center text-[9px] text-[var(--text-secondary)]">
                          占位缩略
                        </div>
                      </div>
                    ))}
                  </div>
                )}
              </section>
            </div>

            {/* 右侧：Phase 2 占位（LoRA / Embedding） + 元信息 */}
            <aside className="space-y-4">
              <div className="placeholder-card rounded-xl p-4">
                <div className="flex items-center justify-between mb-2">
                  <span className="typo-strong text-xs">风格 LoRA</span>
                  <span className="phase-chip">P2</span>
                </div>
                <p className="text-xs text-[var(--text-secondary)] leading-relaxed mb-2">
                  {pack.loraId
                    ? `已绑定：${pack.loraId}（占位）`
                    : "尚未绑定。可通过训练中心生成风格 LoRA 并绑定到此风格。"}
                </p>
                <Link
                  href={`/training/new?type=style&source=${pack.id}`}
                  className="text-xs text-[var(--gold)] hover:underline"
                >
                  前往训练 →
                </Link>
              </div>

              <div className="placeholder-card rounded-xl p-4">
                <div className="flex items-center justify-between mb-2">
                  <span className="typo-strong text-xs">风格 Embedding</span>
                  <span className="phase-chip">P2</span>
                </div>
                <p className="text-xs text-[var(--text-secondary)] leading-relaxed">
                  自动计算的风格向量表示，用于语义检索和相似风格推荐。（占位）
                </p>
              </div>

              <div className="rounded-xl surface-2 p-4">
                <span className="typo-strong text-xs block mb-2">使用统计</span>
                <div className="text-xs text-[var(--text-secondary)] space-y-1">
                  <div>使用次数：{pack.usageCount}</div>
                  <div>
                    来源：
                    {pack.source === "preset" ? "平台预设" : pack.source === "custom" ? "项目自建" : "社区共享"}
                  </div>
                  <div>创建时间：{new Date(pack.createdAt).toLocaleDateString("zh-CN")}</div>
                  <div>更新时间：{new Date(pack.updatedAt).toLocaleDateString("zh-CN")}</div>
                </div>
              </div>
            </aside>
          </div>
        </div>
      </main>
    </div>
  );
}

function KeywordInput({ onAdd }: { onAdd: (kw: string) => void }) {
  const [val, setVal] = useState("");
  return (
    <input
      value={val}
      onChange={(e) => setVal(e.target.value)}
      onKeyDown={(e) => {
        if (e.key === "Enter" && val.trim()) {
          onAdd(val.trim());
          setVal("");
        }
      }}
      placeholder="+ 添加关键词（回车）"
      className="text-xs px-2.5 py-1 rounded-lg bg-[var(--bg-tertiary)] border border-[var(--border)]
                 text-[var(--text-primary)] placeholder:text-[var(--text-secondary)]
                 focus:outline-none focus:border-[var(--accent)]/50 min-w-[120px]"
    />
  );
}

function RefImageCard({
  ref_,
  onRemove,
}: {
  ref_: StyleRefImage;
  onRemove: () => void;
}) {
  return (
    <div className="relative aspect-square rounded-lg overflow-hidden
                    border border-[var(--border)] group">
      {ref_.url ? (
        <img src={ref_.url} alt={ref_.caption} className="w-full h-full object-cover" />
      ) : (
        <div className="w-full h-full bg-gradient-to-br from-[var(--accent)]/10 to-[var(--accent-secondary)]/5
                        flex items-center justify-center">
          <div className="text-center">
            <div className="text-[10px] text-[var(--accent)]/60 mb-0.5">占位</div>
            <div className="text-[9px] text-[var(--text-secondary)]">
              {ref_.caption}
            </div>
          </div>
        </div>
      )}
      <button
        onClick={onRemove}
        className="absolute top-1 right-1 w-5 h-5 rounded-full
                   bg-black/60 text-white text-xs opacity-0 group-hover:opacity-100
                   cursor-pointer transition-opacity flex items-center justify-center"
      >
        ×
      </button>
    </div>
  );
}