import { useSearchExecutions, useExecutionStats, useStatsTimeseries } from '../../api/queries/executions';
import { useExecutionSearch } from './use-execution-search';
import { StatCard } from '../../components/shared/StatCard';
import { Pagination } from '../../components/shared/Pagination';
import { SearchFilters } from './SearchFilters';
import { ResultsTable } from './ResultsTable';
import styles from './ExecutionExplorer.module.css';

function formatCompact(n: number): string {
  if (n >= 1_000_000) return `${(n / 1_000_000).toFixed(1)}M`;
  if (n >= 1_000) return `${(n / 1_000).toFixed(1)}K`;
  return n.toLocaleString();
}

function pctChange(current: number, previous: number): { text: string; direction: 'up' | 'down' | 'neutral' } {
  if (previous === 0) return { text: 'no prior data', direction: 'neutral' };
  const pct = ((current - previous) / previous) * 100;
  if (Math.abs(pct) < 0.5) return { text: '~0% vs yesterday', direction: 'neutral' };
  const arrow = pct > 0 ? '\u2191' : '\u2193';
  return { text: `${arrow} ${Math.abs(pct).toFixed(1)}% vs yesterday`, direction: pct > 0 ? 'up' : 'down' };
}

export function ExecutionExplorer() {
  const { toSearchRequest, offset, limit, setOffset, live, toggleLive } = useExecutionSearch();
  const searchRequest = toSearchRequest();
  const { data, isLoading, isFetching } = useSearchExecutions(searchRequest, live);
  const timeFrom = searchRequest.timeFrom ?? undefined;
  const timeTo = searchRequest.timeTo ?? undefined;
  const { data: stats } = useExecutionStats(timeFrom, timeTo);
  const { data: timeseries } = useStatsTimeseries(timeFrom, timeTo);

  const sparkTotal = timeseries?.buckets.map((b) => b.totalCount) ?? [];
  const sparkFailed = timeseries?.buckets.map((b) => b.failedCount) ?? [];
  const sparkAvgDuration = timeseries?.buckets.map((b) => b.avgDurationMs) ?? [];
  const sparkP99 = timeseries?.buckets.map((b) => b.p99DurationMs) ?? [];
  const sparkActive = timeseries?.buckets.map((b) => b.activeCount) ?? [];

  const total = data?.total ?? 0;
  const results = data?.data ?? [];

  // Failure rate as percentage
  const failureRate = stats && stats.totalCount > 0
    ? (stats.failedCount / stats.totalCount) * 100 : 0;
  const prevFailureRate = stats && stats.prevTotalCount > 0
    ? (stats.prevFailedCount / stats.prevTotalCount) * 100 : 0;

  // Comparison vs yesterday
  const avgChange = stats ? pctChange(stats.avgDurationMs, stats.prevAvgDurationMs) : null;
  const failRateChange = stats ? pctChange(failureRate, prevFailureRate) : null;
  const p99Change = stats ? pctChange(stats.p99LatencyMs, stats.prevP99LatencyMs) : null;

  const showFrom = total > 0 ? offset + 1 : 0;
  const showTo = Math.min(offset + limit, total);

  return (
    <>
      {/* Page Header */}
      <div className={`${styles.pageHeader} animate-in`}>
        <div>
          <h1>Route Explorer</h1>
          <div className={styles.subtitle}>Search and analyze route executions</div>
        </div>
        <button className={`${styles.liveToggle} ${live ? styles.liveOn : styles.liveOff}`} onClick={toggleLive}>
          <span className={styles.liveDot} />
          {live ? 'LIVE' : 'PAUSED'}
        </button>
      </div>

      {/* Stats Bar */}
      <div className={styles.statsBar}>
        <StatCard label="Total Matches" value={total.toLocaleString()} accent="amber" change={stats ? `of ${formatCompact(stats.totalToday)} today` : 'from current search'} sparkData={sparkTotal} />
        <StatCard label="Avg Duration" value={stats ? `${stats.avgDurationMs.toLocaleString()}ms` : '--'} accent="cyan" change={avgChange?.text} changeDirection={avgChange?.direction} sparkData={sparkAvgDuration} />
        <StatCard label="Failure Rate" value={stats ? `${failureRate.toFixed(1)}%` : '--'} accent="rose" change={failRateChange?.text} changeDirection={failRateChange?.direction} sparkData={sparkFailed} />
        <StatCard label="P99 Latency" value={stats ? `${stats.p99LatencyMs.toLocaleString()}ms` : '--'} accent="green" change={p99Change?.text} changeDirection={p99Change?.direction} sparkData={sparkP99} />
        <StatCard label="In-Flight" value={stats ? stats.activeCount.toLocaleString() : '--'} accent="blue" change="running executions" sparkData={sparkActive} />
      </div>

      {/* Filters */}
      <SearchFilters />

      {/* Results Header */}
      <div className={`${styles.resultsHeader} animate-in delay-4`}>
        <span className={styles.resultsCount}>
          Showing <strong>{showFrom}–{showTo}</strong> of <strong>{total.toLocaleString()}</strong> results
          {isFetching && !isLoading && ' · updating...'}
        </span>
      </div>

      {/* Results Table */}
      <ResultsTable results={results} loading={isLoading} />

      {/* Pagination */}
      <Pagination total={total} offset={offset} limit={limit} onChange={setOffset} />
    </>
  );
}
