import { X, Settings, Keyboard, Monitor, Shield, HardDrive, Info, RefreshCw, Grid3X3, Navigation, FileDown, FileUp, FileArchive, Check, Trash2 } from 'lucide-react';
import { useAppStore, type ThemeId } from '../store';
import { useState, useEffect } from 'react';
import { invoke } from '@tauri-apps/api/core';

type Tab = 'general' | 'appearance' | 'shortcuts' | 'privacy' | 'storage' | 'about';
interface ShieldReport { blocked_requests: number; blocked_cosmetic: number; https_upgrades: number; engine_rules: number; }

const THEMES: { id: ThemeId; name: string; description: string; colors: string[] }[] = [
  { id: 'dark-canvas', name: 'Dark Canvas', description: 'Neutral dark background optimized for image reference work. Default.', colors: ['#1C1C1E', '#2A2A2E', '#3A3A3E', '#0A84FF'] },
  { id: 'warm-studio', name: 'Warm Studio', description: 'Warm earthy tones inspired by traditional art studios.', colors: ['#221F1B', '#2E2A24', '#46403A', '#D4A373'] },
  { id: 'midnight', name: 'Midnight', description: 'Deep blue-black for late night sessions with reduced eye strain.', colors: ['#0F1319', '#171D28', '#253040', '#6C89E8'] },
];

export const SettingsPanel = () => {
  const { isSettingsOpen, setIsSettingsOpen, isAlwaysOnTop, setIsAlwaysOnTop, bgOpacity, setBgOpacity, showMinimap, setShowMinimap, showGrid, setShowGrid, theme, setTheme, images, textNotes, annotations, palettes, zoom, pan, boardTitle, setImages, setTextNotes, setAnnotations, setPalettes, setZoom, setPan, setBoardTitle, setCurrentScreen } = useAppStore();
  const [activeTab, setActiveTab] = useState<Tab>('general');
  const [shieldReport, setShieldReport] = useState<ShieldReport>({ blocked_requests: 0, blocked_cosmetic: 0, https_upgrades: 0, engine_rules: 0 });
  const [toastMsg, setToastMsg] = useState('');
  const [isExporting, setIsExporting] = useState(false);

  useEffect(() => { if (isSettingsOpen) invoke<ShieldReport>('shield_get_report').then(setShieldReport).catch(() => {}); }, [isSettingsOpen]);
  useEffect(() => { if (toastMsg) { const t = setTimeout(() => setToastMsg(''), 4000); return () => clearTimeout(t); } }, [toastMsg]);

  // Estimate data size (images as base64 take ~1.37x original size)
  const dataSize = (() => {
    let bytes = 0;
    images.forEach(img => { bytes += (img.url?.length || 0); });
    textNotes.forEach(n => { bytes += (n.text?.length || 0) * 2; });
    annotations.forEach(a => { bytes += a.points.length * 16; });
    if (bytes > 1024 * 1024) return `${(bytes / 1024 / 1024).toFixed(1)} MB`;
    if (bytes > 1024) return `${(bytes / 1024).toFixed(0)} KB`;
    return `${bytes} bytes`;
  })();

  // Export as .refs (portable ZIP with all assets embedded)
  const handleExportRefs = async () => {
    if (isExporting) return;
    setIsExporting(true);
    try {
      const state = JSON.stringify({ title: boardTitle, images, textNotes, annotations, palettes, zoom, pan });
      const bytes = await invoke<number[]>('refs_export', { stateJson: state });
      const blob = new Blob([new Uint8Array(bytes)], { type: 'application/octet-stream' });
      const url = URL.createObjectURL(blob);
      const filename = `${(boardTitle || 'board').replace(/[^a-zA-Z0-9 ]/g, '').trim().replace(/\s+/g, '-').toLowerCase() || 'board'}.refs`;
      const a = document.createElement('a');
      a.href = url; a.download = filename;
      document.body.appendChild(a); a.click(); document.body.removeChild(a); URL.revokeObjectURL(url);
      setToastMsg(`✓ Exported "${filename}" — portable board with all images embedded`);
    } catch (e) {
      setToastMsg(`✗ Export failed: ${e}`);
    }
    setIsExporting(false);
  };

  // Export as JSON (lightweight, URLs only)
  const handleExportJson = () => {
    try {
      const state = { title: boardTitle, images, textNotes, annotations, palettes, zoom, pan };
      const json = JSON.stringify(state, null, 2);
      const blob = new Blob([json], { type: 'application/json' });
      const url = URL.createObjectURL(blob);
      const filename = `${(boardTitle || 'board').replace(/[^a-zA-Z0-9 ]/g, '').trim().replace(/\s+/g, '-').toLowerCase() || 'board'}.json`;
      const a = document.createElement('a'); a.href = url; a.download = filename;
      document.body.appendChild(a); a.click(); document.body.removeChild(a); URL.revokeObjectURL(url);
      setToastMsg(`✓ Exported "${filename}" — lightweight JSON (images as URLs/base64)`);
    } catch (e) { setToastMsg(`✗ Export failed: ${e}`); }
  };

  // Import .refs file
  const handleImportRefs = () => {
    const input = document.createElement('input');
    input.type = 'file'; input.accept = '.refs';
    input.onchange = async (e) => {
      const file = (e.target as HTMLInputElement).files?.[0];
      if (!file) return;
      try {
        const buffer = await file.arrayBuffer();
        const bytes = Array.from(new Uint8Array(buffer));
        const stateJson = await invoke<string>('refs_import', { data: bytes });
        const state = JSON.parse(stateJson);
        if (state.images) setImages(state.images);
        if (state.textNotes) setTextNotes(state.textNotes);
        if (state.annotations) setAnnotations(state.annotations);
        if (state.palettes) setPalettes(state.palettes);
        if (state.zoom) setZoom(state.zoom);
        if (state.pan) setPan(state.pan);
        if (state.title) setBoardTitle(state.title);
        setCurrentScreen('board');
        setToastMsg(`✓ Imported "${file.name}" — ${state.images?.length || 0} images loaded`);
      } catch (e) { setToastMsg(`✗ Import failed: ${e}`); }
    };
    input.click();
  };

  // Import JSON
  const handleImportJson = () => {
    const input = document.createElement('input');
    input.type = 'file'; input.accept = '.json';
    input.onchange = async (e) => {
      const file = (e.target as HTMLInputElement).files?.[0];
      if (!file) return;
      try {
        const text = await file.text();
        const state = JSON.parse(text);
        if (state.images) setImages(state.images);
        if (state.textNotes) setTextNotes(state.textNotes);
        if (state.annotations) setAnnotations(state.annotations);
        if (state.palettes) setPalettes(state.palettes);
        if (state.zoom) setZoom(state.zoom);
        if (state.pan) setPan(state.pan);
        if (state.title) setBoardTitle(state.title);
        setCurrentScreen('board');
        setToastMsg(`✓ Imported "${file.name}"`);
      } catch (e) { setToastMsg(`✗ Import failed: ${e}`); }
    };
    input.click();
  };

  // Clear board
  const handleClearBoard = () => {
    if (!confirm('Clear all images, notes, and annotations from the current board? This cannot be undone.')) return;
    setImages([]); setTextNotes([]); setAnnotations([]); setPalettes([]);
    setToastMsg('Board cleared');
  };

  const tabs: { id: Tab; label: string; icon: React.ReactNode }[] = [
    { id: 'general', label: 'General', icon: <Settings size={16} /> },
    { id: 'appearance', label: 'Appearance', icon: <Monitor size={16} /> },
    { id: 'shortcuts', label: 'Shortcuts', icon: <Keyboard size={16} /> },
    { id: 'privacy', label: 'Privacy', icon: <Shield size={16} /> },
    { id: 'storage', label: 'Storage & Export', icon: <HardDrive size={16} /> },
    { id: 'about', label: 'About', icon: <Info size={16} /> },
  ];

  return (
    <div className={`absolute right-4 top-4 bottom-4 w-[min(680px,calc(100vw-32px))] z-[80] bg-[#1C1C1E]/[0.98] backdrop-blur-xl shadow-2xl border border-white/10 rounded-2xl flex flex-col transform transition-transform duration-500 ease-[cubic-bezier(0.19,1,0.22,1)] overflow-hidden ${isSettingsOpen ? 'translate-x-0' : 'translate-x-[calc(100%+32px)]'}`}>
      <div className="h-14 border-b border-white/5 flex items-center justify-between px-5 bg-black/20 shrink-0">
        <h2 className="text-white font-medium flex items-center gap-2"><Settings size={16} className="text-[#808080]" /> Settings</h2>
        <button onClick={() => setIsSettingsOpen(false)} className="text-[#808080] hover:text-white p-1 rounded-md hover:bg-white/5"><X size={18} /></button>
      </div>
      <div className="flex flex-1 min-h-0 overflow-hidden">
        <nav className="w-[180px] bg-black/10 border-r border-white/5 p-3 flex flex-col gap-1 shrink-0 overflow-y-auto">
          {tabs.map(tab => <button key={tab.id} onClick={() => setActiveTab(tab.id)} className={`flex items-center gap-2.5 px-3 py-2.5 rounded-xl text-[13px] text-left transition-colors ${activeTab === tab.id ? 'bg-[#0A84FF] text-white font-medium' : 'text-[#808080] hover:text-white hover:bg-white/5'}`}>{tab.icon}{tab.label}</button>)}
        </nav>
        <main className="flex-1 min-w-0 overflow-y-auto custom-scrollbar">
          <div className="p-6 pb-10 text-white text-sm max-w-[480px] mx-auto space-y-6">

            {activeTab === 'general' && <>
              <Header title="General" subtitle="Core behavior for the canvas, window, and workspace." />
              <Section title="Window"><ToggleRow label="Always on Top" description="Keep above other apps while drawing." active={isAlwaysOnTop} onToggle={() => setIsAlwaysOnTop(!isAlwaysOnTop)} />{isAlwaysOnTop && <RangeRow label="Overlay opacity" value={bgOpacity} min={10} max={100} suffix="%" onChange={setBgOpacity} />}</Section>
              <Section title="Canvas"><ToggleRow icon={<Grid3X3 size={16} />} label="Grid" description="Show dotted canvas grid." active={showGrid} onToggle={() => setShowGrid(!showGrid)} /><ToggleRow icon={<Navigation size={16} />} label="Minimap" description="Compact board overview in bottom-right." active={showMinimap} onToggle={() => setShowMinimap(!showMinimap)} /></Section>
            </>}

            {activeTab === 'appearance' && <>
              <Header title="Appearance" subtitle="Choose a workspace theme for long sessions." />
              <Section title="Theme"><div className="p-4 grid gap-3">{THEMES.map(t => <button key={t.id} onClick={() => setTheme(t.id)} className={`p-4 rounded-xl border text-left transition-all ${theme === t.id ? 'border-[#0A84FF] bg-[#0A84FF]/8' : 'border-white/10 bg-black/20 hover:border-white/20'}`}><div className="flex items-center justify-between mb-3"><div className="flex gap-2">{t.colors.map(c => <div key={c} className="w-8 h-8 rounded-lg border border-black/30" style={{ backgroundColor: c }} />)}</div>{theme === t.id && <div className="w-6 h-6 rounded-full bg-[#0A84FF] flex items-center justify-center"><Check size={14} /></div>}</div><div className="text-[14px] font-semibold">{t.name}</div><div className="text-[12px] text-[#808080] mt-1">{t.description}</div></button>)}</div></Section>
            </>}

            {activeTab === 'shortcuts' && <>
              <Header title="Keyboard Shortcuts" subtitle="Hotkey-first controls for one-hand artist workflow." />
              <Section title="Panels"><SK combo="B" label="Toggle Browser" /><SK combo="L" label="Toggle Library" /><SK combo="Esc" label="Close panels / clear selection" /><SK combo="Ctrl + ," label="Open Settings" /></Section>
              <Section title="Canvas"><SK combo="Space + Drag" label="Pan canvas" /><SK combo="Scroll" label="Zoom to cursor" /><SK combo="Ctrl + 0" label="Fit all images" /><SK combo="Ctrl + 1" label="100% zoom" /><SK combo="A" label="Toggle annotation mode" /><SK combo="D" label="Desaturate selection" /><SK combo="Shift + D" label="Desaturate all" /><SK combo="H" label="Flip horizontal" /><SK combo="F" label="Focus mode" /><SK combo="V" label="Value mirror" /><SK combo="Z (hold)" label="Zoom lens" /><SK combo="Delete" label="Delete selection" /></Section>
              <Section title="Editing"><SK combo="Ctrl + Z" label="Undo" /><SK combo="Ctrl + Shift + Z" label="Redo" /><SK combo="Ctrl + A" label="Select all" /><SK combo="Ctrl + D" label="Duplicate" /><SK combo="Ctrl + G" label="Group" /><SK combo="Ctrl + Shift + G" label="Ungroup" /></Section>
            </>}

            {activeTab === 'privacy' && <>
              <Header title="Privacy" subtitle="Local-first browsing and capture." />
              <Section title="Muse Shield"><div className="p-4 grid grid-cols-2 gap-3"><Stat value={shieldReport.engine_rules.toLocaleString()} label="Filter rules" /><Stat value={shieldReport.blocked_requests.toLocaleString()} label="Requests blocked" /><Stat value={shieldReport.blocked_cosmetic.toLocaleString()} label="Elements hidden" /><Stat value={shieldReport.https_upgrades.toLocaleString()} label="HTTPS upgrades" /></div><div className="px-4 pb-4"><button onClick={() => invoke('shield_update_lists').catch(() => {})} className="w-full py-2.5 bg-white/5 hover:bg-white/10 rounded-xl border border-white/10 text-sm flex items-center justify-center gap-2"><RefreshCw size={14} /> Update filters</button></div></Section>
              <Section title="Data"><InfoRow label="Privacy model" value="Local-first" description="Everything stays on your machine. No telemetry." /></Section>
            </>}

            {activeTab === 'storage' && <>
              <Header title="Storage & Export" subtitle="Export, import, and manage board data." />

              <Section title="Export as .refs (Portable Archive)">
                <div className="p-4 space-y-3">
                  <p className="text-[12px] text-[#808080] leading-relaxed">Creates a standalone <code className="text-white/70">.refs</code> ZIP archive containing all images, metadata, annotations, and layout. Fully portable — can be opened on any machine without network access.</p>
                  <button onClick={handleExportRefs} disabled={isExporting} className={`w-full py-2.5 bg-[#0A84FF]/10 hover:bg-[#0A84FF]/20 border border-[#0A84FF]/30 rounded-xl text-sm flex items-center justify-center gap-2 text-[#0A84FF] font-medium ${isExporting ? 'opacity-50' : ''}`}><FileArchive size={14} />{isExporting ? 'Exporting...' : 'Export Board as .refs'}</button>
                </div>
              </Section>

              <Section title="Export as JSON (Lightweight)">
                <div className="p-4 space-y-3">
                  <p className="text-[12px] text-[#808080] leading-relaxed">Exports board as a JSON file. Images are stored as base64 data URLs or external URLs depending on how they were captured. Smaller file, requires embedded data to be preserved.</p>
                  <button onClick={handleExportJson} className="w-full py-2.5 bg-white/5 hover:bg-white/10 rounded-xl border border-white/10 text-sm flex items-center justify-center gap-2"><FileDown size={14} /> Export Board as .json</button>
                </div>
              </Section>

              <Section title="Import">
                <div className="p-4 space-y-3">
                  <p className="text-[12px] text-[#808080]">Load a previously exported board file. Replaces current board content.</p>
                  <div className="flex gap-2">
                    <button onClick={handleImportRefs} className="flex-1 py-2.5 bg-white/5 hover:bg-white/10 rounded-xl border border-white/10 text-sm flex items-center justify-center gap-2"><FileUp size={14} /> Import .refs</button>
                    <button onClick={handleImportJson} className="flex-1 py-2.5 bg-white/5 hover:bg-white/10 rounded-xl border border-white/10 text-sm flex items-center justify-center gap-2"><FileUp size={14} /> Import .json</button>
                  </div>
                </div>
              </Section>

              <Section title="Board Statistics">
                <InfoRow label="Images" value={String(images.length)} description="Reference images on canvas" />
                <InfoRow label="Annotations" value={String(annotations.length)} description="Freehand drawing strokes" />
                <InfoRow label="Text Notes" value={String(textNotes.length)} description="Rich text note nodes" />
                <InfoRow label="Estimated Size" value={dataSize} description="Approximate in-memory data footprint" />
                <InfoRow label="Storage Mode" value="Embedded" description="Images stored as base64 inside project — fully portable, no broken links" />
                <InfoRow label="Auto-save" value="Every 800ms" description="Debounced write after each canvas change" />
              </Section>

              <Section title="Danger Zone">
                <div className="p-4 space-y-3">
                  <button onClick={handleClearBoard} className="w-full py-2.5 bg-[#FF453A]/10 hover:bg-[#FF453A]/20 border border-[#FF453A]/30 rounded-xl text-sm flex items-center justify-center gap-2 text-[#FF453A]"><Trash2 size={14} /> Clear Current Board</button>
                </div>
              </Section>
            </>}

            {activeTab === 'about' && <>
              <div className="flex flex-col items-center text-center mt-8 gap-3">
                <div className="w-20 h-20 bg-[#2A2A2E] rounded-2xl flex items-center justify-center"><Monitor size={32} className="text-[#0A84FF]" /></div>
                <h1 className="text-2xl font-semibold">Refstudio</h1>
                <p className="text-[#808080]">1.0.0-alpha</p>
                <p className="max-w-sm text-[#808080] text-sm leading-relaxed">A local-first artist reference board with embedded browser capture, asset library, annotations, and privacy-respecting storage.</p>
                <div className="text-[11px] text-[#606060] mt-4">Built with Tauri v2 + Rust + React<br/>{shieldReport.engine_rules.toLocaleString()} adblock filter rules loaded</div>
              </div>
            </>}
          </div>
        </main>
      </div>

      {/* Toast notification */}
      {toastMsg && <div className="absolute bottom-4 left-4 right-4 z-50 pointer-events-none flex justify-center"><div className="bg-[#2A2A2E] border border-white/10 text-white text-[12px] font-medium px-4 py-2.5 rounded-full shadow-2xl backdrop-blur pointer-events-auto max-w-[400px] truncate">{toastMsg}</div></div>}
    </div>
  );
};

function Header({ title, subtitle }: { title: string; subtitle: string }) { return <div><h1 className="text-2xl font-semibold tracking-tight">{title}</h1><p className="text-sm text-[#808080] mt-1">{subtitle}</p></div>; }
function Section({ title, children }: { title: string; children: React.ReactNode }) { return <section><h3 className="text-[12px] font-semibold uppercase tracking-wider text-[#808080] mb-3">{title}</h3><div className="rounded-2xl border border-white/8 bg-black/20 overflow-hidden divide-y divide-white/5">{children}</div></section>; }
function ToggleRow({ label, description, active, onToggle, icon }: { label: string; description: string; active: boolean; onToggle: () => void; icon?: React.ReactNode }) { return <button type="button" onClick={onToggle} className="w-full px-4 py-3 flex items-center justify-between gap-4 text-left hover:bg-white/[0.03] transition-colors"><div className="flex items-start gap-3 min-w-0 flex-1">{icon && <div className="mt-0.5 text-[#0A84FF] shrink-0">{icon}</div>}<div><div className="text-[14px] font-medium">{label}</div><div className="text-[12px] text-[#808080] mt-0.5">{description}</div></div></div><div className={`relative shrink-0 w-[44px] h-[24px] rounded-full transition-colors ${active ? 'bg-[#0A84FF]' : 'bg-[#3A3A3E]'}`}><div className={`absolute top-[2px] w-5 h-5 rounded-full bg-white shadow-md transition-all ${active ? 'left-[22px]' : 'left-[2px]'}`} /></div></button>; }
function RangeRow({ label, value, min, max, suffix, onChange }: { label: string; value: number; min: number; max: number; suffix: string; onChange: (v: number) => void }) { return <div className="px-4 py-3 flex items-center justify-between gap-4"><span className="text-[13px]">{label}</span><div className="flex items-center gap-3"><span className="text-xs text-[#808080] w-8 text-right">{value}{suffix}</span><input type="range" min={min} max={max} value={value} onChange={e => onChange(Number(e.target.value))} className="w-28 accent-[#0A84FF]" /></div></div>; }
function InfoRow({ label, value, description }: { label: string; value: string; description: string }) { return <div className="px-4 py-3 flex items-center justify-between gap-4"><div><div className="text-[13px] font-medium">{label}</div><div className="text-[11px] text-[#808080] mt-0.5">{description}</div></div><div className="text-[11px] text-[#808080] bg-white/5 border border-white/8 rounded-lg px-2 py-1 shrink-0">{value}</div></div>; }
function SK({ combo, label }: { combo: string; label: string }) { return <div className="px-4 py-2 flex items-center justify-between gap-4"><span className="text-[13px]">{label}</span><kbd className="bg-black/30 border border-white/10 px-2 py-0.5 rounded-lg text-[11px] text-[#808080] font-mono">{combo}</kbd></div>; }
function Stat({ value, label }: { value: string; label: string }) { return <div className="bg-black/20 rounded-xl p-3 text-center border border-white/5"><div className="text-lg font-bold text-[#0A84FF]">{value}</div><div className="text-[10px] text-[#808080] mt-1">{label}</div></div>; }