import { useState, useEffect, useCallback } from 'react';
import { ChevronDown, ChevronRight, Loader2, Tags } from 'lucide-react';
import { logCenterApi } from '@/api/log/log-center';
import { extractLokiSelector, mergeLokiSelector } from './query-builder';
import type { TimeRange } from './types-v3';
import i18n from '@/i18n';

interface Props {
  datasourceId?: number;
  query: string;
  timeRange: TimeRange;
  onQueryChange: (q: string) => void;
}

// Loki Label 浏览器 — 标签名 → 标签值 → 注入 LogQL 选择器 // Logan.Li
export function LokiLabelBrowser({ datasourceId, query, timeRange, onQueryChange }: Props) {
  const [open, setOpen] = useState(false);
  const [labels, setLabels] = useState<string[]>([]);
  const [activeLabel, setActiveLabel] = useState('');
  const [values, setValues] = useState<string[]>([]);
  const [loadingLabels, setLoadingLabels] = useState(false);
  const [loadingValues, setLoadingValues] = useState(false);
  const [selected, setSelected] = useState<Record<string, string>>({});

  const timeParams = useCallback(() => ({
    start: timeRange.start.replace(' ', 'T'),
    end: timeRange.end.replace(' ', 'T'),
  }), [timeRange]);

  useEffect(() => {
    if (!open || !datasourceId) return;
    // eslint-disable-next-line react-hooks/set-state-in-effect
    setLoadingLabels(true);
    logCenterApi.listLokiLabels(datasourceId, timeParams())
      .then((res) => setLabels(Array.isArray(res) ? res : []))
      .catch(() => setLabels([]))
      .finally(() => setLoadingLabels(false));
  }, [open, datasourceId, timeParams]);

  useEffect(() => {
    if (!activeLabel || !datasourceId) {
      // eslint-disable-next-line react-hooks/set-state-in-effect
      setValues([]);
      return;
    }
    setLoadingValues(true);
    const selector = extractLokiSelector(query);
    logCenterApi.listLokiLabelValues(datasourceId, activeLabel, {
      ...timeParams(),
      ...(selector ? { query: selector } : {}),
    })
      .then((res) => setValues(Array.isArray(res) ? res : []))
      .catch(() => setValues([]))
      .finally(() => setLoadingValues(false));
  }, [activeLabel, datasourceId, query, timeParams]);

  const applySelection = (label: string, value: string) => {
    const next = { ...selected, [label]: value };
    setSelected(next);
    onQueryChange(mergeLokiSelector(query, next));
  };

  return (
    <div className="rounded-lg border" style={{ borderColor: 'var(--dg-border)', background: 'var(--dg-bg-secondary)' }}>
      <button
        type="button"
        onClick={() => setOpen(!open)}
        className="w-full flex items-center gap-2 px-3 py-2 text-xs font-medium"
        style={{ color: 'var(--dg-text-secondary)' }}
      >
        {open ? <ChevronDown className="h-3.5 w-3.5" /> : <ChevronRight className="h-3.5 w-3.5" />}
        <Tags className="h-3.5 w-3.5" style={{ color: '#06b6d4' }} />
        Label 浏览器
        {Object.keys(selected).length > 0 && (
          <span className="text-[10px] px-1.5 py-0.5 rounded" style={{ background: 'var(--dg-bg-tertiary)', color: 'var(--dg-text-muted)' }}>
            已选 {Object.keys(selected).length}
          </span>
        )}
      </button>
      {open && (
        <div className="flex border-t min-h-[140px]" style={{ borderColor: 'var(--dg-border)' }}>
          <div className="w-36 border-r overflow-y-auto max-h-48" style={{ borderColor: 'var(--dg-border)' }}>
            {loadingLabels ? (
              <div className="flex justify-center py-6"><Loader2 className="h-4 w-4 animate-spin text-[var(--dg-text-muted)]" /></div>
            ) : labels.map((lb) => (
              <button
                key={lb}
                type="button"
                onClick={() => setActiveLabel(lb)}
                className="w-full text-left px-2 py-1.5 text-[11px] font-mono truncate"
                style={{
                  color: activeLabel === lb ? '#06b6d4' : 'var(--dg-text-secondary)',
                  background: activeLabel === lb ? 'var(--dg-bg-tertiary)' : 'transparent',
                }}
              >
                {lb}
              </button>
            ))}
          </div>
          <div className="flex-1 overflow-y-auto max-h-48 p-1">
            {!activeLabel && <p className="text-[11px] px-2 py-4 text-center" style={{ color: 'var(--dg-text-muted)' }}> {i18n.t('monitor.lokilabelbrowse.s088b9477')} </p>}
            {loadingValues && <div className="flex justify-center py-6"><Loader2 className="h-4 w-4 animate-spin" /></div>}
            {!loadingValues && activeLabel && values.map((v) => (
              <button
                key={v}
                type="button"
                onClick={() => applySelection(activeLabel, v)}
                className="w-full text-left px-2 py-1 text-[11px] font-mono truncate rounded hover:opacity-80"
                style={{
                  color: selected[activeLabel] === v ? '#22c55e' : 'var(--dg-text-primary)',
                  background: selected[activeLabel] === v ? 'rgba(34,197,94,0.1)' : 'transparent',
                }}
              >
                {v}
              </button>
            ))}
          </div>
        </div>
      )}
    </div>
  );
}