'use client';

import { useState, useCallback } from 'react';
import { AnimationSettings } from './AnimationSettings';
import { AnimationPreview } from './AnimationPreview';
import { KeyframeTimeline } from './KeyframeTimeline';
import { KeyframeProperties } from './KeyframeProperties';
import { PresetLibrary } from './PresetLibrary';
import { ExportPanel } from './ExportPanel';
import { DEFAULT_CONFIG, newKeyframe } from '@/lib/animate/defaults';
import { cn } from '@/lib/utils/cn';
import type { AnimationConfig, KeyframeProperties as KFProps, PreviewElement } from '@/types/animate';

type MobileTab = 'edit' | 'preview';
type RightTab = 'keyframes' | 'export' | 'presets';

export function AnimationEditor() {
  const [config, setConfig] = useState<AnimationConfig>(DEFAULT_CONFIG);
  const [selectedId, setSelectedId] = useState<string | null>(
    DEFAULT_CONFIG.keyframes[DEFAULT_CONFIG.keyframes.length - 1].id
  );
  const [previewElement, setPreviewElement] = useState<PreviewElement>('box');
  const [mobileTab, setMobileTab] = useState<MobileTab>('edit');
  const [rightTab, setRightTab] = useState<RightTab>('export');

  const selectedKeyframe = config.keyframes.find((k) => k.id === selectedId) ?? null;

  const updateKeyframeProps = useCallback((id: string, props: KFProps) => {
    setConfig((c) => ({
      ...c,
      keyframes: c.keyframes.map((k) => k.id === id ? { ...k, properties: props } : k),
    }));
  }, []);

  const addKeyframe = useCallback((offset: number) => {
    const kf = newKeyframe(offset);
    setConfig((c) => ({ ...c, keyframes: [...c.keyframes, kf] }));
    setSelectedId(kf.id);
  }, []);

  const deleteKeyframe = useCallback((id: string) => {
    setConfig((c) => {
      if (c.keyframes.length <= 2) return c;
      return { ...c, keyframes: c.keyframes.filter((k) => k.id !== id) };
    });
    setSelectedId((prev) => {
      if (prev !== id) return prev;
      const remaining = config.keyframes.filter((k) => k.id !== id);
      return remaining[remaining.length - 1]?.id ?? null;
    });
  }, [config.keyframes]);

  const moveKeyframe = useCallback((id: string, newOffset: number) => {
    const clamped = Math.min(100, Math.max(0, Math.round(newOffset)));
    setConfig((c) => ({
      ...c,
      keyframes: c.keyframes.map((k) => k.id === id ? { ...k, offset: clamped } : k),
    }));
  }, []);

  const loadPreset = useCallback((presetConfig: AnimationConfig) => {
    setConfig(presetConfig);
    setSelectedId(presetConfig.keyframes[presetConfig.keyframes.length - 1].id);
  }, []);

  const timelineProps = {
    keyframes: config.keyframes,
    selectedId,
    onSelect: setSelectedId,
    onAdd: addKeyframe,
    onDelete: deleteKeyframe,
    onMove: moveKeyframe,
  };

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

      {/* ── Mobile tab switcher ─────────────────────────────── */}
      <div className="flex lg:hidden glass rounded-xl p-1 gap-1">
        {(['edit', 'preview'] 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 === 'edit' ? 'Edit' : 'Preview'}
          </button>
        ))}
      </div>

      {/* ── Main layout ─────────────────────────────────────── */}
      <div
        className="grid grid-cols-1 lg:grid-cols-5 gap-4"
        style={{ height: 'calc(100svh - 120px)'  }}
      >

        {/* Left: Settings + Properties */}
        <div className={cn('lg:col-span-2 flex flex-col overflow-hidden', mobileTab !== 'edit' && 'hidden lg:flex')}>
          <div className="glass rounded-xl p-4 flex flex-col flex-1 min-h-0 overflow-hidden">
            <div className="flex-1 min-h-0 overflow-y-auto scrollbar-thin scrollbar-thumb-primary/20 scrollbar-track-transparent pr-0.5 space-y-5">

              <AnimationSettings config={config} onChange={setConfig} />

              <div className="border-t border-border/25" />

              <KeyframeTimeline {...timelineProps} embedded />

              <KeyframeProperties keyframe={selectedKeyframe} onChange={updateKeyframeProps} />
            </div>
          </div>
        </div>

        {/* Right: Preview + tabbed panel */}
        <div className={cn('lg:col-span-3 flex flex-col gap-3 overflow-hidden', mobileTab !== 'preview' && 'hidden lg:flex')}>

          {/* Preview canvas */}
          <AnimationPreview config={config} element={previewElement} onElementChange={setPreviewElement} />

          {/* Keyframes / Export / Presets tab panel */}
          <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">
              {(['export', 'presets'] as RightTab[]).map((t) => (
                <button
                  key={t}
                  onClick={() => setRightTab(t)}
                  className={cn(
                    'flex-1 py-1.5 rounded-md text-xs font-medium capitalize transition-all',
                    rightTab === t
                      ? 'bg-primary text-primary-foreground shadow-sm'
                      : 'text-muted-foreground hover:text-foreground'
                  )}
                >
                  {t === 'export' ? 'Export' : 'Presets'}
                </button>
              ))}
            </div>
            {/* Content */}
            {rightTab === 'export' && <ExportPanel config={config} />}
            {rightTab === 'presets' && <PresetLibrary onSelect={loadPreset} />}
          </div>
        </div>
      </div>
    </div>
  );
}