"use client";

import { useState } from "react";

import type { ForeshadowView } from "@/lib/api/types";
import type { ForeshadowStatus } from "@/lib/foreshadow/board";

interface ForeshadowCardProps {
  item: ForeshadowView;
  overdue: boolean;
  busy: boolean;
  onTransition: (
    code: string,
    toStatus: ForeshadowStatus | null,
    progressNote: string,
  ) => void;
}

const NEXT_STATUS: Record<string, ForeshadowStatus[]> = {
  OPEN: ["PARTIAL", "CLOSED"],
  PARTIAL: ["CLOSED"],
  OVERDUE: ["PARTIAL", "CLOSED"],
  CLOSED: [],
};

// 伏笔卡（UX §6.8）：code/title/回收窗口/importance/progress 时间线 + 状态变更/加进展。
// OVERDUE 用琥珀强调（不单靠色：加 ⚠ 图标 + 文案，a11y §10）。
export function ForeshadowCard({
  item,
  overdue,
  busy,
  onTransition,
}: ForeshadowCardProps) {
  const [note, setNote] = useState("");
  const transitions = NEXT_STATUS[item.status] ?? [];
  const windowText = recoveryWindow(item);

  return (
    <li
      className={`rounded border bg-panel p-3 ${
        overdue ? "border-overdue ring-1 ring-overdue/40" : "border-line"
      }`}
    >
      <div className="flex items-baseline gap-2">
        <span className="font-mono text-xs text-cinnabar">{item.code}</span>
        {overdue ? (
          <span className="text-xs text-overdue" aria-label="逾期">
            ⚠ 逾期
          </span>
        ) : null}
      </div>
      <p className="mt-0.5 font-serif text-sm text-ink">{item.title}</p>

      <dl className="mt-2 space-y-0.5 text-xs text-ink-soft">
        {typeof item.planted_at === "number" ? (
          <div>埋于 {item.planted_at} 章</div>
        ) : null}
        {windowText ? <div>窗口 {windowText}</div> : null}
        {item.importance ? <div>{item.importance}</div> : null}
      </dl>

      {item.progress && item.progress.length > 0 ? (
        <ul className="mt-2 border-l-2 border-line pl-2 text-xs text-ink-soft">
          {item.progress.map((p, i) => (
            <li key={i}>· {progressLabel(p)}</li>
          ))}
        </ul>
      ) : null}

      {transitions.length > 0 || item.status !== "CLOSED" ? (
        <div className="mt-3 space-y-2">
          {transitions.length > 0 ? (
            <div className="flex flex-wrap gap-1.5">
              {transitions.map((to) => (
                <button
                  key={to}
                  type="button"
                  disabled={busy}
                  onClick={() => onTransition(item.code, to, "")}
                  className="rounded border border-line px-2 py-0.5 text-xs text-ink hover:border-cinnabar hover:text-cinnabar disabled:opacity-40"
                >
                  → {to === "CLOSED" ? "回收" : to}
                </button>
              ))}
            </div>
          ) : null}
          {item.status !== "CLOSED" ? (
            <div className="flex gap-1.5">
              <label htmlFor={`prog-${item.code}`} className="sr-only">
                {item.code} 进展
              </label>
              <input
                id={`prog-${item.code}`}
                type="text"
                value={note}
                onChange={(e) => setNote(e.target.value)}
                placeholder="加进展（如：23章发光）"
                className="min-w-0 flex-1 rounded border border-line bg-bg px-2 py-0.5 text-xs text-ink focus:border-cinnabar focus:outline-none"
              />
              <button
                type="button"
                disabled={busy || note.trim().length === 0}
                onClick={() => {
                  onTransition(item.code, null, note.trim());
                  setNote("");
                }}
                className="rounded border border-line px-2 py-0.5 text-xs text-ink hover:border-cinnabar disabled:opacity-40"
              >
                记
              </button>
            </div>
          ) : null}
        </div>
      ) : null}
    </li>
  );
}

function recoveryWindow(item: ForeshadowView): string | null {
  const from = item.expected_close_from;
  const to = item.expected_close_to;
  if (typeof from === "number" && typeof to === "number") return `${from}-${to}`;
  if (typeof to === "number") return `≤${to}`;
  if (typeof from === "number") return `≥${from}`;
  return null;
}

function progressLabel(entry: Record<string, unknown>): string {
  const chapter = entry["chapter"];
  const note = entry["note"];
  const noteStr = typeof note === "string" ? note : JSON.stringify(entry);
  return typeof chapter === "number" ? `${chapter}章：${noteStr}` : noteStr;
}
