'use client';

import { useState, useEffect, Suspense } from 'react';
import { useSearchParams, useRouter } from 'next/navigation';
import { ColorPicker } from '@/components/color/ColorPicker';
import { ColorInfo } from '@/components/color/ColorInfo';
import { ManipulationPanel } from '@/components/color/ManipulationPanel';
import { PaletteGrid } from '@/components/color/PaletteGrid';
import { ExportMenu } from '@/components/color/ExportMenu';
import { useColorInfo, useGeneratePalette, useGenerateGradient } from '@/lib/color/api/queries';
import { Loader2, Share2, Plus, X, Palette, Layers } from 'lucide-react';
import { toast } from 'sonner';
import { cn } from '@/lib/utils';

type HarmonyType = 'monochromatic' | 'analogous' | 'complementary' | 'triadic' | 'tetradic';
type RightTab = 'info' | 'adjust' | 'harmony' | 'gradient';
type MobileTab = 'pick' | 'explore';

const HARMONY_OPTS: { value: HarmonyType; label: string; desc: string }[] = [
  { value: 'monochromatic', label: 'Mono', desc: 'Single hue, varied lightness' },
  { value: 'analogous', label: 'Analogous', desc: 'Adjacent colors ±30°' },
  { value: 'complementary', label: 'Complement', desc: 'Opposite on wheel 180°' },
  { value: 'triadic', label: 'Triadic', desc: 'Three equal 120° steps' },
  { value: 'tetradic', label: 'Tetradic', desc: 'Four equal 90° steps' },
];

const RIGHT_TABS: { value: RightTab; label: string }[] = [
  { value: 'info', label: 'Info' },
  { value: 'adjust', label: 'Adjust' },
  { value: 'harmony', label: 'Harmony' },
  { value: 'gradient', label: 'Gradient' },
];

const actionBtn =
  'flex items-center gap-1 px-2.5 py-1 text-xs glass rounded-md border border-border/30 text-muted-foreground hover:text-primary hover:border-primary/30 hover:bg-primary/10 transition-all disabled:opacity-40 disabled:cursor-not-allowed';

function ColorManipulationContent() {
  const searchParams = useSearchParams();
  const router = useRouter();
  const [color, setColor] = useState(() => {
    const urlColor = searchParams.get('color');
    return urlColor ? `#${urlColor.replace('#', '')}` : '#ff0099';
  });

  const [rightTab, setRightTab] = useState<RightTab>('info');
  const [mobileTab, setMobileTab] = useState<MobileTab>('pick');

  // Harmony
  const [harmonyType, setHarmonyType] = useState<HarmonyType>('complementary');
  const [palette, setPalette] = useState<string[]>([]);
  const paletteMutation = useGeneratePalette();

  // Gradient
  const [stops, setStops] = useState<string[]>(['#ff0099', '#0099ff']);
  const [gradientCount, setGradientCount] = useState(10);
  const [gradientResult, setGradientResult] = useState<string[]>([]);
  const gradientMutation = useGenerateGradient();

  const { data, isLoading } = useColorInfo({ colors: [color] });
  const colorInfo = data?.colors[0];

  useEffect(() => {
    const hex = color.replace('#', '');
    if (hex.length === 6 || hex.length === 3) {
      router.push(`/color?color=${hex}`, { scroll: false });
    }
  }, [color, router]);

  // Sync first gradient stop with active color
  useEffect(() => {
    setStops((prev) => [color, ...prev.slice(1)]);
  }, [color]);

  const handleShare = () => {
    navigator.clipboard.writeText(`${window.location.origin}/color?color=${color.replace('#', '')}`);
    toast.success('Link copied!');
  };

  const generateHarmony = async () => {
    try {
      const result = await paletteMutation.mutateAsync({ base: color, scheme: harmonyType });
      setPalette([result.palette.primary, ...result.palette.secondary]);
      toast.success(`Generated ${harmonyType} palette`);
    } catch { toast.error('Failed to generate palette'); }
  };

  const generateGradient = async () => {
    try {
      const result = await gradientMutation.mutateAsync({ stops, count: gradientCount });
      setGradientResult(result.gradient);
      toast.success(`Generated ${result.gradient.length} colors`);
    } catch { toast.error('Failed to generate gradient'); }
  };

  const updateStop = (i: number, v: string) => {
    const next = [...stops];
    next[i] = v;
    setStops(next);
    if (i === 0) setColor(v);
  };

  return (
    <div className="flex flex-col gap-4">

      {/* ── Mobile tab switcher ────────────────────────────────── */}
      <div className="flex lg:hidden glass rounded-xl p-1 gap-1">
        {(['pick', 'explore'] as MobileTab[]).map((t) => (
          <button
            key={t}
            onClick={() => setMobileTab(t)}
            className={cn(
              'flex-1 py-2.5 rounded-lg text-sm font-medium capitalize transition-all',
              mobileTab === t
                ? 'bg-primary text-primary-foreground shadow-sm'
                : 'text-muted-foreground hover:text-foreground'
            )}
          >
            {t === 'pick' ? 'Pick' : 'Explore'}
          </button>
        ))}
      </div>

      {/* ── Main layout ────────────────────────────────────────── */}
      <div
        className="grid grid-cols-1 lg:grid-cols-5 gap-4"
        style={{ height: 'calc(100svh - 180px)'  }}
      >

        {/* Left panel: Picker + ColorInfo */}
        <div
          className={cn(
            'lg:col-span-2 flex flex-col gap-3 overflow-hidden',
            mobileTab !== 'pick' && 'hidden lg:flex'
          )}
        >
          {/* Color picker card */}
          <div className="glass rounded-xl p-4 shrink-0">
            <div className="flex items-center justify-between mb-3">
              <span className="text-[10px] font-semibold text-muted-foreground uppercase tracking-widest">
                Color
              </span>
              <button onClick={handleShare} className={actionBtn}>
                <Share2 className="w-3 h-3" /> Share
              </button>
            </div>
            <ColorPicker color={color} onChange={setColor} />
          </div>

          {/* Color info card */}
          <div className="glass rounded-xl p-4 flex flex-col flex-1 min-h-0 overflow-hidden">
            <span className="text-[10px] font-semibold text-muted-foreground uppercase tracking-widest block mb-3 shrink-0">
              Info
            </span>
            <div className="flex-1 min-h-0 overflow-y-auto scrollbar-thin scrollbar-thumb-primary/20 scrollbar-track-transparent">
              {isLoading ? (
                <div className="flex justify-center py-8">
                  <Loader2 className="w-4 w-4 animate-spin text-muted-foreground/40" />
                </div>
              ) : colorInfo ? (
                <ColorInfo info={colorInfo} />
              ) : null}
            </div>
          </div>
        </div>

        {/* Right panel: tabbed tools */}
        <div
          className={cn(
            'lg:col-span-3 flex flex-col overflow-hidden',
            mobileTab !== 'explore' && 'hidden lg:flex'
          )}
        >
          <div className="glass rounded-xl p-4 flex flex-col flex-1 min-h-0 overflow-hidden">

            {/* Tab switcher */}
            <div className="flex glass rounded-lg p-0.5 gap-0.5 mb-4 shrink-0">
              {RIGHT_TABS.map(({ value, label }) => (
                <button
                  key={value}
                  onClick={() => setRightTab(value)}
                  className={cn(
                    'flex-1 py-1.5 rounded-md text-xs font-medium transition-all',
                    rightTab === value
                      ? 'bg-primary text-primary-foreground shadow-sm'
                      : 'text-muted-foreground hover:text-foreground'
                  )}
                >
                  {label}
                </button>
              ))}
            </div>

            {/* Tab content */}
            <div className="flex-1 min-h-0 overflow-y-auto scrollbar-thin scrollbar-thumb-primary/20 scrollbar-track-transparent pr-0.5">

              {/* ── Info tab ─────────────────────────────── */}
              {rightTab === 'info' && (
                <div className="space-y-3">
                  {/* Large color preview */}
                  <div
                    className="w-full rounded-xl border border-white/8 transition-colors duration-300"
                    style={{ height: '140px', background: color }}
                  />
                  {isLoading ? (
                    <div className="flex justify-center py-6">
                      <Loader2 className="w-5 h-5 animate-spin text-muted-foreground/40" />
                    </div>
                  ) : colorInfo ? (
                    <ColorInfo info={colorInfo} />
                  ) : null}
                </div>
              )}

              {/* ── Adjust tab ───────────────────────────── */}
              {rightTab === 'adjust' && (
                <ManipulationPanel color={color} onColorChange={setColor} />
              )}

              {/* ── Harmony tab ──────────────────────────── */}
              {rightTab === 'harmony' && (
                <div className="space-y-4">
                  {/* Scheme selector */}
                  <div className="space-y-2">
                    <span className="text-[10px] font-semibold text-muted-foreground uppercase tracking-widest">
                      Scheme
                    </span>
                    <div className="flex flex-wrap gap-1.5">
                      {HARMONY_OPTS.map((opt) => (
                        <button
                          key={opt.value}
                          onClick={() => setHarmonyType(opt.value)}
                          className={cn(
                            'px-2.5 py-1 rounded-lg border text-xs font-mono transition-all',
                            harmonyType === opt.value
                              ? 'bg-primary/10 border-primary/40 text-primary'
                              : 'border-border/30 text-muted-foreground hover:border-primary/30 hover:text-foreground'
                          )}
                        >
                          {opt.label}
                        </button>
                      ))}
                    </div>
                    <p className="text-[10px] text-muted-foreground/50 font-mono">
                      {HARMONY_OPTS.find((o) => o.value === harmonyType)?.desc}
                    </p>
                  </div>

                  <button
                    onClick={generateHarmony}
                    disabled={paletteMutation.isPending}
                    className={cn(actionBtn, 'w-full justify-center py-2')}
                  >
                    {paletteMutation.isPending
                      ? <><Loader2 className="w-3 h-3 animate-spin" /> Generating…</>
                      : <><Palette className="w-3 h-3" /> Generate Palette</>
                    }
                  </button>

                  {palette.length > 0 && (
                    <div className="space-y-4">
                      <PaletteGrid colors={palette} onColorClick={setColor} />
                      <div className="border-t border-border/25 pt-4">
                        <ExportMenu colors={palette} />
                      </div>
                    </div>
                  )}
                </div>
              )}

              {/* ── Gradient tab ─────────────────────────── */}
              {rightTab === 'gradient' && (
                <div className="space-y-4">
                  {/* Color stops */}
                  <div className="space-y-2">
                    <span className="text-[10px] font-semibold text-muted-foreground uppercase tracking-widest">
                      Stops
                    </span>
                    {stops.map((stop, i) => (
                      <div key={i} className="flex items-center gap-2">
                        <input
                          type="color"
                          value={stop}
                          onChange={(e) => updateStop(i, e.target.value)}
                          className="w-8 h-8 rounded-lg cursor-pointer border border-border/40 bg-transparent shrink-0 p-0.5"
                        />
                        <input
                          type="text"
                          value={stop}
                          onChange={(e) => updateStop(i, e.target.value)}
                          className="flex-1 bg-transparent border border-border/40 rounded-lg px-2.5 py-1.5 text-xs font-mono outline-none focus:border-primary/50 transition-colors"
                        />
                        {i !== 0 && stops.length > 2 && (
                          <button
                            onClick={() => setStops(stops.filter((_, idx) => idx !== i))}
                            className="shrink-0 text-muted-foreground/35 hover:text-destructive transition-colors"
                          >
                            <X className="w-3.5 h-3.5" />
                          </button>
                        )}
                      </div>
                    ))}
                    <button
                      onClick={() => setStops([...stops, '#000000'])}
                      className="w-full py-1.5 rounded-lg border border-dashed border-border/30 text-xs text-muted-foreground/40 hover:text-foreground hover:border-primary/30 transition-all flex items-center justify-center gap-1"
                    >
                      <Plus className="w-3 h-3" /> Add stop
                    </button>
                  </div>

                  {/* Steps */}
                  <div className="flex items-center gap-3">
                    <span className="text-[10px] font-semibold text-muted-foreground uppercase tracking-widest shrink-0">
                      Steps
                    </span>
                    <input
                      type="number"
                      min={2}
                      max={100}
                      value={gradientCount}
                      onChange={(e) => setGradientCount(parseInt(e.target.value))}
                      className="w-20 bg-transparent border border-border/40 rounded-lg px-2.5 py-1.5 text-xs font-mono text-center outline-none focus:border-primary/50 transition-colors"
                    />
                  </div>

                  <button
                    onClick={generateGradient}
                    disabled={gradientMutation.isPending}
                    className={cn(actionBtn, 'w-full justify-center py-2')}
                  >
                    {gradientMutation.isPending
                      ? <><Loader2 className="w-3 h-3 animate-spin" /> Generating…</>
                      : <><Layers className="w-3 h-3" /> Generate Gradient</>
                    }
                  </button>

                  {gradientResult.length > 0 && (
                    <div className="space-y-4">
                      {/* Gradient preview bar */}
                      <div
                        className="h-12 w-full rounded-xl border border-white/8"
                        style={{ background: `linear-gradient(to right, ${gradientResult.join(', ')})` }}
                      />
                      <PaletteGrid colors={gradientResult} onColorClick={setColor} />
                      <div className="border-t border-border/25 pt-4">
                        <ExportMenu colors={gradientResult} />
                      </div>
                    </div>
                  )}
                </div>
              )}

            </div>
          </div>
        </div>
      </div>
    </div>
  );
}

export function ColorManipulation() {
  return (
    <Suspense fallback={
      <div className="flex items-center justify-center py-12">
        <Loader2 className="h-8 w-8 animate-spin text-muted-foreground/40" />
      </div>
    }>
      <ColorManipulationContent />
    </Suspense>
  );
}
