import { useEffect, useState } from 'react';
import { Link } from 'framework7-react';
import { apiClient, errorMessage, HealthDay } from '../services/api';
import Screen from '../components/Screen';
import Ring from '../components/charts/Ring';
import MetricCard from '../components/charts/MetricCard';
import MetricStrip from '../components/charts/MetricStrip';
import Skeleton from '../components/Skeleton';
import { useCountUp } from '../lib/motion';
import './Today.css';

const DAYS = 30;

function StepHero({ today, history }: { today: HealthDay; history: HealthDay[] }) {
  const goal = today.stepGoal ?? null;
  const steps = today.steps ?? null;
  const progress = steps != null && goal ? steps / goal : null;
  const animated = useCountUp(steps);

  const week = history.slice(-7).map((d) => d.steps).filter((v): v is number => v != null);
  const weekAvg = week.length
    ? Math.round(week.reduce((a, b) => a + b, 0) / week.length)
    : null;
  const remaining = steps != null && goal ? goal - steps : null;

  return (
    <section className="hero">
      <Ring
        progress={progress}
        label={`步数完成度 ${progress != null ? Math.round(progress * 100) : 0}%`}
      >
        <span className="hero-value">
          {steps == null ? '—' : Math.round(animated ?? steps).toLocaleString()}
        </span>
        <span className="hero-caption">步</span>
      </Ring>

      <div className="hero-facts">
        <div className="hero-headline">
          {progress == null
            ? '今日暂无步数记录'
            : progress >= 1
            ? '今日目标已完成'
            : `距目标还差 ${remaining!.toLocaleString()} 步`}
        </div>
        <dl className="hero-list">
          <div><dt>目标</dt><dd>{goal ? goal.toLocaleString() : '—'}</dd></div>
          <div><dt>近 7 日均</dt><dd>{weekAvg ? weekAvg.toLocaleString() : '—'}</dd></div>
          <div><dt>完成度</dt><dd>{progress != null ? `${Math.round(progress * 100)}%` : '—'}</dd></div>
        </dl>
      </div>
    </section>
  );
}

function TodayPage() {
  const [days, setDays] = useState<HealthDay[]>([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState('');

  useEffect(() => {
    const load = async () => {
      try {
        const end = new Date();
        const start = new Date(end.getTime() - (DAYS - 1) * 86400000);
        setDays(await apiClient.getHealthSummary(
          start.toISOString().slice(0, 10), end.toISOString().slice(0, 10)
        ));
      } catch (err: any) {
        setError(errorMessage(err, '加载数据失败'));
      } finally {
        setLoading(false);
      }
    };
    load();
  }, []);

  const today = days[days.length - 1];

  return (
    <Screen title="今日" subtitle={today?.date}>
      {loading && (
        <>
          <div className="hero-skeleton" aria-hidden="true" />
          <Skeleton count={4} />
        </>
      )}

      {!loading && error && <div className="screen-error">{error}</div>}

      {!loading && !error && !today && (
        <div className="screen-empty">
          <p>还没有任何健康数据。</p>
          <Link href="/sync/" className="button button-fill button-round">
            去同步 Garmin 数据
          </Link>
        </div>
      )}

      {!loading && !error && today && (
        <>
          <StepHero today={today} history={days} />

          <section className="sec">
            <h3 className="sec-title">活动</h3>
            <div className="mcard-grid">
              <MetricCard metric="steps" label="步数" value={today.steps} unit="步"
                trend={days.map((d) => d.steps)} />
              <MetricCard metric="intensityMinutes" label="强度分钟" value={today.intensityMinutes}
                unit="分钟" trend={days.map((d) => d.intensityMinutes)} />
              <MetricCard metric="floorsAscended" label="爬楼" value={today.floorsAscended}
                unit="层" trend={days.map((d) => d.floorsAscended)} />
              <MetricCard label="距离" unit="km" decimals={2}
                value={today.distanceMeters != null ? today.distanceMeters / 1000 : null}
                trend={days.map((d) => d.distanceMeters)}
                detail={today.caloriesBurned != null
                  ? `消耗 ${Math.round(today.caloriesBurned).toLocaleString()} kcal` : undefined} />
            </div>
          </section>

          <section className="sec">
            <h3 className="sec-title">心率与压力</h3>
            <div className="mcard-grid">
              <MetricCard metric="heartRate" label="静息心率" value={today.heartRate} unit="bpm"
                trend={days.map((d) => d.heartRate)} />
              <MetricCard metric="heartRateVariability" label="心率变异性"
                value={today.heartRateVariability} unit="ms" decimals={1}
                trend={days.map((d) => d.heartRateVariability)} />
              <MetricCard metric="stress" label="平均压力" value={today.stress}
                trend={days.map((d) => d.stress)} />
              <MetricCard metric="trainingReadiness" label="训练准备度"
                value={today.trainingReadiness} unit="/100"
                trend={days.map((d) => d.trainingReadiness)} />
            </div>
          </section>

          <section className="sec">
            <h3 className="sec-title">睡眠</h3>
            <div className="mcard-grid">
              <MetricCard metric="sleepDuration" label="睡眠时长" value={today.sleepDuration}
                unit="小时" decimals={1} trend={days.map((d) => d.sleepDuration)} />
              <MetricCard metric="sleepQuality" label="睡眠评分" value={today.sleepQuality}
                unit="/100" trend={days.map((d) => d.sleepQuality)} />
            </div>
            <p className="sec-link"><Link href="/sleep/">查看睡眠分期详情 →</Link></p>
          </section>

          <section className="sec">
            <MetricStrip title="身体指标" items={[
              { metric: 'heartRateVariability', icon: '💓', label: 'HRV', value: today.heartRateVariability, unit: 'ms' },
              { metric: 'heartRate', icon: '❤️', label: '静息心率', value: today.heartRate, unit: 'bpm' },
              { metric: 'respirationAvg', icon: '🫁', label: '呼吸', value: today.respirationAvg, unit: '次/分', decimals: 1 },
              { metric: 'spo2Avg', icon: '🩸', label: '血氧', value: today.spo2Avg, unit: '%' },
              { metric: 'bodyBatteryHigh', icon: '🔋', label: '身体电量', value: today.bodyBatteryHigh, unit: '峰值' },
            ]} />
          </section>
        </>
      )}
    </Screen>
  );
}

export default TodayPage;