import { useEffect, useState } from "react";
import { Link } from "react-router-dom";
import { useTranslation } from "react-i18next";
import { useSettings } from "../settings";
import { useAuth } from "../auth";
import { useToast } from "../toast";
import { api } from "../api";
import Icon from "../components/Icon";
import PolicyCard from "./settings/PolicyCard";
import RestoreCard from "./settings/RestoreCard";

export default function Settings() {
  const { t } = useTranslation();
  const s = useSettings();
  const { isAdmin } = useAuth();
  const toast = useToast();
  const [flagged, setFlagged] = useState([]);

  async function ladenFlagged() {
    try { setFlagged(await api.flaggedKeywords()); }
    catch { /* still ignorieren – nicht kritisch für die Einstellungen */ }
  }
  useEffect(() => { ladenFlagged(); }, []);

  async function keywordBehalten(id) {
    try { await api.confirmKeyword(id); setFlagged((f) => f.filter((x) => x.id !== id)); }
    catch (err) { toast(err.message, "error"); }
  }
  async function keywordEntfernen(id) {
    try { await api.deleteKeyword(id); setFlagged((f) => f.filter((x) => x.id !== id)); }
    catch (err) { toast(err.message, "error"); }
  }

  async function set(key, value) {
    try {
      await s.update(key, value);
      toast(t("settings.saved"));
    } catch (err) {
      toast(err.message, "error");
    }
  }

  async function dl(fn) {
    try {
      await fn();
    } catch (err) {
      toast(err.message, "error");
    }
  }

  return (
    <div>
      <h1>{t("settings.title")}</h1>

      {flagged.length > 0 && (
        <div className="card" style={{ maxWidth: 520, marginBottom: "var(--sp-4)", borderColor: "var(--danger)" }}>
          <h2 style={{ display: "flex", alignItems: "center", gap: "var(--sp-2)", marginTop: 0 }}>
            <Icon name="alert" size={18} /> {t("settings.keywordReview")}
          </h2>
          <p className="muted small">{t("settings.keywordReviewHint")}</p>
          {flagged.map((f) => (
            <div className="kw-flag" key={f.id}>
              <div className="kw-flag-main">
                <div className="ellipsis">
                  <span className="kw-flag-word">{f.word}</span>
                  <Icon name="chevron-right" size={12} /> {f.category_name}
                </div>
                <div className="muted small">
                  {t("settings.keywordCorrected", { overridden: f.overridden_count, applied: f.applied_count })}
                </div>
              </div>
              <button className="btn sm" onClick={() => keywordBehalten(f.id)}>{t("settings.keep")}</button>
              <button className="btn sm danger" onClick={() => keywordEntfernen(f.id)}>{t("settings.remove")}</button>
            </div>
          ))}
        </div>
      )}

      <div className="card" style={{ maxWidth: 520 }}>
        <label>
          <span>{t("settings.baseCurrency")}</span>
          <select value={s.base_currency} onChange={(e) => set("base_currency", e.target.value)}>
            <option value="EUR">Euro (EUR)</option>
            <option value="CHF">Schweizer Franken (CHF)</option>
          </select>
        </label>
        <p className="muted small" style={{ marginTop: -8 }}>{t("settings.baseCurrencyHint")}</p>

        <label>
          <span>{t("settings.locale")}</span>
          <select value={s.locale} onChange={(e) => set("locale", e.target.value)}>
            <option value="de">{t("settings.languageDe")}</option>
            <option value="en">{t("settings.languageEn")}</option>
          </select>
        </label>

        <label>
          <span>{t("settings.theme")}</span>
          <select value={s.theme} onChange={(e) => set("theme", e.target.value)}>
            <option value="system">{t("settings.themeSystem")}</option>
            <option value="light">{t("settings.themeLight")}</option>
            <option value="dark">{t("settings.themeDark")}</option>
          </select>
        </label>

        <label>
          <span>{t("settings.budgetStartDay")}</span>
          <input
            type="number"
            min="1"
            max="31"
            value={s.budget_start_day}
            onChange={(e) => {
              const day = Math.max(1, Math.min(31, Number(e.target.value) || 1));
              set("budget_start_day", String(day));
            }}
          />
        </label>
        <p className="muted small" style={{ marginTop: -8 }}>{t("settings.budgetStartDayHint")}</p>
      </div>

      <div className="card" style={{ maxWidth: 520, marginTop: "var(--sp-4)" }}>
        <h2 style={{ display: "flex", alignItems: "center", gap: "var(--sp-2)", marginTop: 0 }}>
          <Icon name="shield" size={18} /> {t("settings.security")}
        </h2>
        <p className="muted small">{t("settings.securityHint")}</p>
        <Link className="btn" to="/zwei-faktor">
          <Icon name="smartphone" size={15} /> {t("settings.twoFactor")}
        </Link>
      </div>

      {isAdmin && <PolicyCard />}

      <div className="card" style={{ maxWidth: 520, marginTop: "var(--sp-4)" }}>
        <h2>{t("settings.backup")}</h2>
        <p className="muted small">{t("settings.backupHint")}</p>
        <button className="btn primary" onClick={() => dl(api.exportBackupJson)}>
          <Icon name="download" size={15} /> {t("settings.exportBackup")}
        </button>

        <p className="muted small" style={{ marginTop: "var(--sp-4)" }}>{t("settings.exportHint")}</p>
        <div className="field-inline" style={{ flexWrap: "wrap" }}>
          <button className="btn" onClick={() => dl(api.exportTransactionsCsv)}>
            <Icon name="download" size={15} /> {t("settings.exportTxnCsv")}
          </button>
          <button className="btn" onClick={() => dl(api.exportTransactionsJson)}>
            <Icon name="download" size={15} /> {t("settings.exportTxnJson")}
          </button>
          <button className="btn" onClick={() => dl(api.exportAllJson)}>
            <Icon name="download" size={15} /> {t("settings.exportAll")}
          </button>
        </div>

        {isAdmin && (
          <>
            <p className="muted small" style={{ marginTop: "var(--sp-4)" }}>{t("settings.dbBackupHint")}</p>
            <div className="field-inline" style={{ flexWrap: "wrap" }}>
              <button className="btn" onClick={() => dl(api.downloadDbBackup)}>
                <Icon name="download" size={15} /> {t("settings.dbBackup")}
              </button>
              <button className="btn" onClick={() => dl(api.exportSystemBackupJson)}>
                <Icon name="download" size={15} /> {t("settings.systemBackup")}
              </button>
            </div>
            <div className="alert warn" style={{ marginTop: "var(--sp-3)" }}>
              <Icon name="alert" size={16} />
              <span>{t("settings.systemBackupWarning")}</span>
            </div>
          </>
        )}
      </div>

      <RestoreCard />
    </div>
  );
}