"use client";

import { useEffect, useState } from "react";
import Link from "next/link";
import {
  importCanonScene,
  listCanonWorks,
  listCharacters,
  type CanonWork,
  type CharacterSummary,
  type ImportSceneLineInput,
  type ImportedSceneResult,
  type SceneLineType,
} from "../../lib/api";

const LINE_TYPE_LABELS: Record<SceneLineType, string> = {
  DIALOGUE: "台詞",
  ACTION: "動作描寫",
  MONOLOGUE: "內心獨白",
  NARRATION: "敘述",
};

function emptyLine(): ImportSceneLineInput {
  return { lineType: "NARRATION", rawText: "" };
}

// T19-P4 匯入章節：場景層級的摘要／原文＋逐句台詞。多人在場且台詞沒有明示說話者時，M-3／M-11
// 既有的發言歸屬會把信心不足的句子隔離（QUARANTINED），提交後直接依回應導向待裁決頁或顯示已投影。
export function CanonImportView() {
  const [works, setWorks] = useState<CanonWork[]>([]);
  const [workId, setWorkId] = useState("");
  const [characters, setCharacters] = useState<CharacterSummary[]>([]);
  const [chapterLabel, setChapterLabel] = useState("");
  const [volume, setVolume] = useState(1);
  const [storyOrder, setStoryOrder] = useState(1);
  const [summary, setSummary] = useState("");
  const [rawText, setRawText] = useState("");
  const [participantCharacterIds, setParticipantCharacterIds] = useState<string[]>([]);
  const [lines, setLines] = useState<ImportSceneLineInput[]>([emptyLine()]);
  const [pending, setPending] = useState(false);
  const [error, setError] = useState<string | null>(null);
  const [result, setResult] = useState<ImportedSceneResult | null>(null);

  useEffect(() => {
    void listCanonWorks().then((all) => {
      setWorks(all);
      const presetWorkId = new URLSearchParams(window.location.search).get("workId");
      if (presetWorkId && all.some((w) => w.id === presetWorkId)) {
        setWorkId(presetWorkId);
      }
    });
  }, []);

  useEffect(() => {
    const selected = works.find((w) => w.id === workId);
    setStoryOrder((selected?.anchorStoryOrder ?? 0) + 1);
    setParticipantCharacterIds([]);
    setResult(null);
    setError(null);
    if (workId) {
      void listCharacters().then((all) => setCharacters(all.filter((c) => c.workId === workId)));
    } else {
      setCharacters([]);
    }
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [workId]);

  function toggleParticipant(characterId: string) {
    setParticipantCharacterIds((prev) =>
      prev.includes(characterId) ? prev.filter((id) => id !== characterId) : [...prev, characterId],
    );
  }

  function updateLine(index: number, patch: Partial<ImportSceneLineInput>) {
    setLines((prev) => prev.map((line, i) => (i === index ? { ...line, ...patch } : line)));
  }

  function removeLine(index: number) {
    setLines((prev) => prev.filter((_, i) => i !== index));
  }

  async function handleSubmit() {
    if (!workId || !chapterLabel.trim() || !summary.trim() || !rawText.trim() || pending) return;
    setPending(true);
    setError(null);
    setResult(null);
    try {
      const imported = await importCanonScene({
        workId,
        volume,
        chapterLabel: chapterLabel.trim(),
        storyOrder,
        summary: summary.trim(),
        rawText: rawText.trim(),
        participantCharacterIds,
        lines: lines.filter((line) => line.rawText.trim().length > 0),
      });
      setResult(imported);
      setChapterLabel("");
      setSummary("");
      setRawText("");
      setLines([emptyLine()]);
    } catch (err) {
      setError(err instanceof Error ? err.message : "章節匯入失敗，請確認 api 服務是否已啟動");
    } finally {
      setPending(false);
    }
  }

  return (
    <div className="flex flex-col gap-4">
      <select
        value={workId}
        onChange={(event) => setWorkId(event.target.value)}
        className="rounded-full border bg-transparent px-3 py-2 text-sm"
        style={{ borderColor: "var(--line)", color: "var(--ink)" }}
      >
        <option value="">選擇作品……</option>
        {works.map((w) => (
          <option key={w.id} value={w.id}>
            {w.title}
          </option>
        ))}
      </select>

      {error && (
        <p className="text-xs" style={{ color: "var(--accent)" }}>
          {error}
        </p>
      )}

      {result && (
        <div className="flex flex-col gap-1 rounded-2xl border p-3 text-xs" style={{ borderColor: "var(--line)" }}>
          {result.pendingAdjudication ? (
            <>
              <p style={{ color: "var(--ink)" }}>匯入成功，但有台詞或矛盾待人工確認，暫不投影。</p>
              <Link href="/canon-review" className="font-bold" style={{ color: "var(--accent)" }}>
                前往待裁決頁
              </Link>
            </>
          ) : (
            <p style={{ color: "var(--ink)" }}>匯入成功，已完成投影{result.projected ? "" : "（場景超前目前錨定點，先留存等待錨定點推進）"}。</p>
          )}
        </div>
      )}

      {workId && (
        <>
          <div className="flex flex-wrap gap-2">
            <input
              value={chapterLabel}
              onChange={(event) => setChapterLabel(event.target.value)}
              placeholder="章節標題（例如：第十章）"
              className="flex-1 rounded-full border bg-transparent px-3 py-2 text-sm outline-none"
              style={{ borderColor: "var(--line)", color: "var(--ink)" }}
            />
            <input
              type="number"
              value={volume}
              onChange={(event) => setVolume(Number(event.target.value))}
              placeholder="卷數"
              className="w-20 rounded-full border bg-transparent px-3 py-2 text-sm outline-none"
              style={{ borderColor: "var(--line)", color: "var(--ink)" }}
            />
            <input
              type="number"
              value={storyOrder}
              onChange={(event) => setStoryOrder(Number(event.target.value))}
              placeholder="storyOrder"
              className="w-28 rounded-full border bg-transparent px-3 py-2 text-sm outline-none"
              style={{ borderColor: "var(--line)", color: "var(--ink)" }}
            />
          </div>

          <textarea
            value={summary}
            onChange={(event) => setSummary(event.target.value)}
            placeholder="場景摘要（客觀記錄，供角色記憶與情緒基線使用）"
            className="rounded-2xl border bg-transparent p-3 text-sm outline-none"
            style={{ borderColor: "var(--line)", color: "var(--ink)" }}
            rows={3}
          />

          <textarea
            value={rawText}
            onChange={(event) => setRawText(event.target.value)}
            placeholder="原文（完整章節文本）"
            className="rounded-2xl border bg-transparent p-3 text-sm outline-none"
            style={{ borderColor: "var(--line)", color: "var(--ink)" }}
            rows={5}
          />

          <div className="flex flex-col gap-2">
            <p className="text-xs font-bold" style={{ color: "var(--ink)" }}>
              在場角色
            </p>
            <div className="flex flex-wrap gap-2 text-xs">
              {characters.map((character) => (
                <button
                  key={character.id}
                  type="button"
                  onClick={() => toggleParticipant(character.id)}
                  className="rounded-full border px-3 py-1"
                  style={{
                    borderColor: "var(--line)",
                    background: participantCharacterIds.includes(character.id) ? "var(--chip-bg)" : "transparent",
                    color: "var(--ink)",
                  }}
                >
                  {character.aliases[0]?.formalName ?? character.id}
                </button>
              ))}
            </div>
          </div>

          <div className="flex flex-col gap-2">
            <div className="flex items-center justify-between">
              <p className="text-xs font-bold" style={{ color: "var(--ink)" }}>
                逐句台詞／敘述
              </p>
              <button
                type="button"
                onClick={() => setLines((prev) => [...prev, emptyLine()])}
                className="rounded-full border px-3 py-1 text-xs"
                style={{ borderColor: "var(--line)", color: "var(--ink-soft)" }}
              >
                新增一行
              </button>
            </div>
            {lines.map((line, index) => (
              <div key={index} className="flex flex-wrap items-center gap-2 text-xs">
                <select
                  value={line.lineType}
                  onChange={(event) => updateLine(index, { lineType: event.target.value as SceneLineType })}
                  className="rounded-full border bg-transparent px-2 py-1"
                  style={{ borderColor: "var(--line)", color: "var(--ink)" }}
                >
                  {(Object.keys(LINE_TYPE_LABELS) as SceneLineType[]).map((type) => (
                    <option key={type} value={type}>
                      {LINE_TYPE_LABELS[type]}
                    </option>
                  ))}
                </select>
                <input
                  value={line.rawText}
                  onChange={(event) => updateLine(index, { rawText: event.target.value })}
                  placeholder="這一句的內容"
                  className="flex-1 rounded-full border bg-transparent px-3 py-1 outline-none"
                  style={{ borderColor: "var(--line)", color: "var(--ink)" }}
                />
                {line.lineType === "DIALOGUE" && (
                  <select
                    value={line.markerCharacterId ?? ""}
                    onChange={(event) =>
                      updateLine(index, {
                        markerCharacterId: event.target.value || undefined,
                        hasExplicitMarker: Boolean(event.target.value),
                      })
                    }
                    className="rounded-full border bg-transparent px-2 py-1"
                    style={{ borderColor: "var(--line)", color: "var(--ink)" }}
                  >
                    <option value="">（無明示說話者）</option>
                    {characters.map((character) => (
                      <option key={character.id} value={character.id}>
                        {character.aliases[0]?.formalName ?? character.id}
                      </option>
                    ))}
                  </select>
                )}
                <button
                  type="button"
                  onClick={() => removeLine(index)}
                  className="rounded-full border px-2 py-1"
                  style={{ borderColor: "var(--line)", color: "var(--ink-soft)" }}
                >
                  刪除
                </button>
              </div>
            ))}
          </div>

          <button
            type="button"
            onClick={() => void handleSubmit()}
            disabled={pending || !chapterLabel.trim() || !summary.trim() || !rawText.trim()}
            className="self-start rounded-full px-4 py-2 text-sm font-bold text-white disabled:opacity-50"
            style={{ background: "var(--accent-bright)" }}
          >
            匯入這一章
          </button>
        </>
      )}
    </div>
  );
}