import { useEffect, useRef, useState } from 'react'
import { api, ApiError, type Integration } from '../lib/api'
import { useAuth } from '../lib/AuthContext'
import {
  User,
  Palette,
  Plug,
  Bell,
  Database,
  Info,
  Eye,
  EyeOff,
  Check,
  Download,
  Upload,
  Trash2,
  RotateCcw,
  Camera,
} from 'lucide-react'

const navSections = [
  { id: 'profile', label: 'Profile', icon: User },
  { id: 'appearance', label: 'Appearance', icon: Palette },
  { id: 'integrations', label: 'Integrations', icon: Plug },
  { id: 'notifications', label: 'Notifications', icon: Bell },
  { id: 'data', label: 'Data & Backup', icon: Database },
  { id: 'about', label: 'About', icon: Info },
]

const accentColors = [
  { name: 'Gold', color: '#C8A434' },
  { name: 'Teal', color: '#2DD4BF' },
  { name: 'Purple', color: '#A855F7' },
  { name: 'Blue', color: '#3B82F6' },
  { name: 'Green', color: '#2ECC71' },
  { name: 'Red', color: '#E74C3C' },
]

type FieldDef = { key: string; label: string; secret?: boolean }

const integrationTypeDefs: { type: string; name: string; fields: FieldDef[] }[] = [
  { type: 'proxmox', name: 'Proxmox', fields: [{ key: 'baseUrl', label: 'Host URL' }, { key: 'apiKey', label: 'API Token', secret: true }] },
  { type: 'docker', name: 'Docker', fields: [{ key: 'baseUrl', label: 'Socket / Remote URL' }] },
  { type: 'netbird', name: 'NetBird', fields: [{ key: 'apiKey', label: 'API Key', secret: true }] },
  { type: 'cloudflare', name: 'Cloudflare', fields: [{ key: 'apiKey', label: 'API Token', secret: true }, { key: 'zoneId', label: 'Zone ID' }] },
  { type: 'aws', name: 'AWS', fields: [{ key: 'accessKey', label: 'Access Key' }, { key: 'secretKey', label: 'Secret', secret: true }, { key: 'region', label: 'Region' }] },
  { type: 'uptime_kuma', name: 'Uptime Kuma', fields: [{ key: 'baseUrl', label: 'URL' }, { key: 'apiKey', label: 'API Key', secret: true }] },
  { type: 'weather', name: 'Weather API', fields: [{ key: 'location', label: 'Location' }, { key: 'units', label: 'Units' }] },
]

const cardBase: React.CSSProperties = {
  backgroundColor: 'rgba(10, 10, 12, 0.92)',
  border: '1px solid rgba(200, 164, 52, 0.08)',
  borderRadius: '12px',
  padding: '22px',
  position: 'relative',
}

const sectionTitle: React.CSSProperties = {
  fontSize: '11px',
  textTransform: 'uppercase',
  letterSpacing: '1.5px',
  color: '#7A7D85',
  fontWeight: 500,
  marginBottom: '16px',
}

const labelStyle: React.CSSProperties = {
  fontSize: '11px',
  color: '#7A7D85',
  marginBottom: '6px',
  display: 'block',
}

const inputStyle: React.CSSProperties = {
  width: '100%',
  height: '34px',
  borderRadius: '8px',
  border: '1px solid rgba(200,164,52,0.12)',
  backgroundColor: 'rgba(255,255,255,0.03)',
  color: '#E8E6E0',
  fontSize: '12px',
  padding: '0 12px',
  outline: 'none',
}

function Toggle({ on, onClick }: { on: boolean; onClick: () => void }) {
  return (
    <button
      onClick={onClick}
      className="cursor-pointer border-none"
      style={{
        width: '38px',
        height: '20px',
        borderRadius: '10px',
        backgroundColor: on ? '#C8A434' : 'rgba(255,255,255,0.08)',
        position: 'relative',
        transition: 'background-color 0.2s ease',
        flexShrink: 0,
      }}
    >
      <span
        style={{
          position: 'absolute',
          top: '2px',
          left: on ? '20px' : '2px',
          width: '16px',
          height: '16px',
          borderRadius: '50%',
          backgroundColor: '#0A0B0D',
          transition: 'left 0.2s ease',
        }}
      />
    </button>
  )
}

function GoldButton({ children, danger, onClick, disabled }: { children: React.ReactNode; danger?: boolean; onClick?: () => void; disabled?: boolean }) {
  return (
    <button
      onClick={onClick}
      disabled={disabled}
      className="flex items-center gap-2 cursor-pointer transition-colors whitespace-nowrap"
      style={{
        fontSize: '12px',
        fontWeight: 600,
        color: danger ? '#E74C3C' : '#0A0B0D',
        backgroundColor: danger ? 'transparent' : '#C8A434',
        border: danger ? '1px solid rgba(231,76,60,0.4)' : 'none',
        borderRadius: '8px',
        padding: '9px 16px',
        boxShadow: danger ? 'none' : '0 0 14px rgba(200,164,52,0.2)',
        opacity: disabled ? 0.6 : 1,
      }}
    >
      {children}
    </button>
  )
}

function ProfileSection() {
  const { user, setUser } = useAuth()
  const fileInputRef = useRef<HTMLInputElement>(null)
  const [displayName, setDisplayName] = useState(user?.display_name ?? '')
  const [email, setEmail] = useState(user?.email ?? '')
  const [avatar, setAvatar] = useState<string | null>(user?.avatar_data_url ?? null)
  const [saving, setSaving] = useState(false)
  const [savedMsg, setSavedMsg] = useState('')

  useEffect(() => {
    setDisplayName(user?.display_name ?? '')
    setEmail(user?.email ?? '')
    setAvatar(user?.avatar_data_url ?? null)
  }, [user])

  const initials = (displayName || user?.username || '?').slice(0, 2).toUpperCase()

  function handleAvatarChange(e: React.ChangeEvent<HTMLInputElement>) {
    const file = e.target.files?.[0]
    if (!file) return
    const reader = new FileReader()
    reader.onload = () => setAvatar(reader.result as string)
    reader.readAsDataURL(file)
  }

  async function handleSave() {
    setSaving(true)
    setSavedMsg('')
    try {
      const { user: updated } = await api.updateMe({ displayName, email, avatarDataUrl: avatar })
      setUser(updated)
      setSavedMsg('Saved')
    } catch (err) {
      setSavedMsg(err instanceof ApiError ? err.message : 'Failed to save')
    } finally {
      setSaving(false)
    }
  }

  return (
    <div style={cardBase}>
      <h3 style={sectionTitle}>Profile</h3>
      <div className="flex items-center gap-4" style={{ marginBottom: '24px' }}>
        <div
          onClick={() => fileInputRef.current?.click()}
          className="relative rounded-full border-2 flex items-center justify-center font-bold cursor-pointer group"
          style={{
            width: '64px',
            height: '64px',
            borderColor: '#C8A434',
            color: '#C8A434',
            fontSize: '20px',
            backgroundColor: 'rgba(200,164,52,0.08)',
            backgroundImage: avatar ? `url(${avatar})` : undefined,
            backgroundSize: 'cover',
            backgroundPosition: 'center',
            overflow: 'hidden',
          }}
          title="Upload photo"
        >
          {!avatar && initials}
          <div
            className="absolute inset-0 flex items-center justify-center opacity-0 group-hover:opacity-100 transition-opacity"
            style={{ backgroundColor: 'rgba(0,0,0,0.55)' }}
          >
            <Camera size={18} color="#E8E6E0" />
          </div>
        </div>
        <input ref={fileInputRef} type="file" accept="image/*" onChange={handleAvatarChange} className="hidden" />
        <div>
          <span style={{ fontSize: '15px', color: '#E8E6E0', fontWeight: 600 }}>{displayName || user?.username}</span>
          <br />
          <span style={{ fontSize: '12px', color: '#7A7D85' }}>{email || 'No email set'}</span>
        </div>
      </div>
      <div className="grid grid-cols-2 gap-4" style={{ marginBottom: '20px' }}>
        <div>
          <label style={labelStyle}>Display Name</label>
          <input style={inputStyle} value={displayName} onChange={(e) => setDisplayName(e.target.value)} />
        </div>
        <div>
          <label style={labelStyle}>Email</label>
          <input style={inputStyle} value={email} onChange={(e) => setEmail(e.target.value)} />
        </div>
      </div>
      <div className="flex items-center gap-3">
        <GoldButton onClick={handleSave} disabled={saving}>
          <Check size={14} />
          {saving ? 'Saving…' : 'Save Changes'}
        </GoldButton>
        {savedMsg && <span style={{ fontSize: '12px', color: '#7A7D85' }}>{savedMsg}</span>}
      </div>
    </div>
  )
}

function AppearanceSection() {
  const [theme, setTheme] = useState<'dark' | 'light'>('dark')
  const [accent, setAccent] = useState('Gold')
  const [fontSize, setFontSize] = useState(13)
  const [radius, setRadius] = useState(12)
  const [sidebarExpanded, setSidebarExpanded] = useState(true)
  const [animations, setAnimations] = useState(true)

  return (
    <div style={cardBase}>
      <h3 style={sectionTitle}>Appearance</h3>

      <div className="flex items-center justify-between" style={{ marginBottom: '20px' }}>
        <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Theme</span>
        <div className="flex items-center gap-1" style={{ backgroundColor: 'rgba(255,255,255,0.03)', borderRadius: '8px', padding: '3px' }}>
          {(['dark', 'light'] as const).map((t) => (
            <button
              key={t}
              onClick={() => setTheme(t)}
              className="cursor-pointer border-none capitalize"
              style={{
                fontSize: '11px',
                padding: '6px 14px',
                borderRadius: '6px',
                color: theme === t ? '#0A0B0D' : '#7A7D85',
                backgroundColor: theme === t ? '#C8A434' : 'transparent',
                fontWeight: 600,
              }}
            >
              {t}
            </button>
          ))}
        </div>
      </div>

      <div style={{ marginBottom: '20px' }}>
        <span style={{ fontSize: '13px', color: '#E8E6E0', marginBottom: '10px', display: 'block' }}>Accent Color</span>
        <div className="flex items-center gap-3">
          {accentColors.map((a) => (
            <button
              key={a.name}
              onClick={() => setAccent(a.name)}
              title={a.name}
              className="cursor-pointer border-none rounded-full flex items-center justify-center"
              style={{
                width: '28px',
                height: '28px',
                backgroundColor: a.color,
                outline: accent === a.name ? `2px solid ${a.color}` : 'none',
                outlineOffset: '3px',
              }}
            >
              {accent === a.name && <Check size={14} color="#0A0B0D" />}
            </button>
          ))}
        </div>
      </div>

      <div style={{ marginBottom: '20px' }}>
        <div className="flex items-center justify-between" style={{ marginBottom: '8px' }}>
          <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Font Size</span>
          <span style={{ fontSize: '11px', color: '#C8A434' }}>{fontSize}px</span>
        </div>
        <input
          type="range"
          min={12}
          max={16}
          value={fontSize}
          onChange={(e) => setFontSize(Number(e.target.value))}
          className="w-full"
          style={{ accentColor: '#C8A434' }}
        />
      </div>

      <div style={{ marginBottom: '20px' }}>
        <div className="flex items-center justify-between" style={{ marginBottom: '8px' }}>
          <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Card Border Radius</span>
          <span style={{ fontSize: '11px', color: '#C8A434' }}>{radius}px</span>
        </div>
        <input
          type="range"
          min={4}
          max={16}
          value={radius}
          onChange={(e) => setRadius(Number(e.target.value))}
          className="w-full"
          style={{ accentColor: '#C8A434' }}
        />
      </div>

      <div className="flex items-center justify-between" style={{ marginBottom: '16px' }}>
        <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Sidebar Expanded by Default</span>
        <Toggle on={sidebarExpanded} onClick={() => setSidebarExpanded((v) => !v)} />
      </div>

      <div className="flex items-center justify-between">
        <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Animations</span>
        <Toggle on={animations} onClick={() => setAnimations((v) => !v)} />
      </div>
    </div>
  )
}

function IntegrationsSection() {
  const [integrations, setIntegrations] = useState<Integration[] | null>(null)
  const [revealed, setRevealed] = useState<Set<string>>(new Set())
  const [drafts, setDrafts] = useState<Record<string, Record<string, string>>>({})
  const [statusMsg, setStatusMsg] = useState<Record<string, string>>({})
  const [busy, setBusy] = useState<Set<string>>(new Set())

  useEffect(() => {
    api.listIntegrations().then(({ integrations }) => setIntegrations(integrations))
  }, [])

  function toggleReveal(key: string) {
    setRevealed((prev) => {
      const next = new Set(prev)
      if (next.has(key)) next.delete(key)
      else next.add(key)
      return next
    })
  }

  function setBusyFlag(type: string, value: boolean) {
    setBusy((prev) => {
      const next = new Set(prev)
      if (value) next.add(type)
      else next.delete(type)
      return next
    })
  }

  function setDraftField(type: string, fieldKey: string, value: string) {
    setDrafts((prev) => ({ ...prev, [type]: { ...prev[type], [fieldKey]: value } }))
  }

  async function handleSave(def: (typeof integrationTypeDefs)[number], existing: Integration | undefined) {
    setBusyFlag(def.type, true)
    setStatusMsg((prev) => ({ ...prev, [def.type]: '' }))
    try {
      const draft = drafts[def.type] ?? {}
      const config: Record<string, string> = {}
      const secrets: Record<string, string> = {}
      for (const f of def.fields) {
        const value = draft[f.key]
        if (value === undefined) continue
        if (f.secret) secrets[f.key] = value
        else config[f.key] = value
      }
      let integration: Integration
      if (existing) {
        ;({ integration } = await api.updateIntegration(existing.id, { config, secrets }))
      } else {
        ;({ integration } = await api.createIntegration({ type: def.type, name: def.name, config, secrets }))
      }
      setIntegrations((prev) => {
        const others = (prev ?? []).filter((i) => i.id !== integration.id)
        return [...others, integration]
      })
      setStatusMsg((prev) => ({ ...prev, [def.type]: 'Saved' }))
    } catch (err) {
      setStatusMsg((prev) => ({ ...prev, [def.type]: err instanceof ApiError ? err.message : 'Save failed' }))
    } finally {
      setBusyFlag(def.type, false)
    }
  }

  async function handleTest(def: (typeof integrationTypeDefs)[number], existing: Integration | undefined) {
    if (!existing) {
      setStatusMsg((prev) => ({ ...prev, [def.type]: 'Save the integration before testing' }))
      return
    }
    setBusyFlag(def.type, true)
    try {
      const result = await api.testIntegration(existing.id)
      setStatusMsg((prev) => ({ ...prev, [def.type]: result.message }))
      const { integrations } = await api.listIntegrations()
      setIntegrations(integrations)
    } catch (err) {
      setStatusMsg((prev) => ({ ...prev, [def.type]: err instanceof ApiError ? err.message : 'Test failed' }))
    } finally {
      setBusyFlag(def.type, false)
    }
  }

  if (!integrations) {
    return (
      <div style={cardBase}>
        <p style={{ fontSize: '12px', color: '#7A7D85' }}>Loading integrations…</p>
      </div>
    )
  }

  return (
    <div className="flex flex-col gap-4">
      {integrationTypeDefs.map((def) => {
        const existing = integrations.find((i) => i.type === def.type)
        const online = existing?.status === 'connected'
        const draft = drafts[def.type] ?? {}

        return (
          <div key={def.type} style={cardBase}>
            <div className="flex items-center justify-between" style={{ marginBottom: '16px' }}>
              <div className="flex items-center gap-2.5">
                <span
                  style={{
                    width: '8px',
                    height: '8px',
                    borderRadius: '50%',
                    backgroundColor: online ? '#2ECC71' : '#4A4D55',
                    boxShadow: online ? '0 0 6px rgba(46,204,113,0.6)' : 'none',
                  }}
                />
                <span style={{ fontSize: '13px', color: '#E8E6E0', fontWeight: 600 }}>{def.name}</span>
              </div>
              <div className="flex items-center gap-2">
                {statusMsg[def.type] && (
                  <span style={{ fontSize: '11px', color: '#7A7D85' }}>{statusMsg[def.type]}</span>
                )}
                <button
                  onClick={() => handleSave(def, existing)}
                  disabled={busy.has(def.type)}
                  className="cursor-pointer border-none"
                  style={{
                    fontSize: '11px',
                    fontWeight: 600,
                    color: '#0A0B0D',
                    backgroundColor: '#C8A434',
                    borderRadius: '6px',
                    padding: '6px 12px',
                    opacity: busy.has(def.type) ? 0.6 : 1,
                  }}
                >
                  Save
                </button>
                <button
                  onClick={() => handleTest(def, existing)}
                  disabled={busy.has(def.type)}
                  className="cursor-pointer border-none"
                  style={{
                    fontSize: '11px',
                    fontWeight: 600,
                    color: '#C8A434',
                    backgroundColor: 'rgba(200,164,52,0.08)',
                    border: '1px solid rgba(200,164,52,0.2)',
                    borderRadius: '6px',
                    padding: '6px 12px',
                    opacity: busy.has(def.type) ? 0.6 : 1,
                  }}
                >
                  Test Connection
                </button>
              </div>
            </div>
            <div className="grid grid-cols-3 gap-4">
              {def.fields.map((f) => {
                const key = `${def.type}-${f.key}`
                const isRevealed = revealed.has(key)
                const savedValue = f.secret ? '' : existing?.config[f.key] ?? ''
                const value = draft[f.key] ?? savedValue
                return (
                  <div key={key}>
                    <label style={labelStyle}>{f.label}</label>
                    <div className="relative">
                      <input
                        style={inputStyle}
                        type={f.secret && !isRevealed ? 'password' : 'text'}
                        value={value}
                        onChange={(e) => setDraftField(def.type, f.key, e.target.value)}
                        placeholder={f.secret && existing ? '••••••••••••' : 'Not configured'}
                      />
                      {f.secret && (
                        <button
                          onClick={() => toggleReveal(key)}
                          className="absolute cursor-pointer border-none bg-transparent"
                          style={{ right: '8px', top: '50%', transform: 'translateY(-50%)', color: '#7A7D85' }}
                        >
                          {isRevealed ? <EyeOff size={13} /> : <Eye size={13} />}
                        </button>
                      )}
                    </div>
                  </div>
                )
              })}
            </div>
          </div>
        )
      })}
    </div>
  )
}

function NotificationsSection() {
  const [enabled, setEnabled] = useState(true)
  const [email, setEmail] = useState(true)
  const [push, setPush] = useState(false)
  const [sound, setSound] = useState(true)

  return (
    <div style={cardBase}>
      <h3 style={sectionTitle}>Notifications</h3>

      <div className="flex items-center justify-between" style={{ marginBottom: '20px' }}>
        <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Enable Notifications</span>
        <Toggle on={enabled} onClick={() => setEnabled((v) => !v)} />
      </div>

      <div style={{ marginBottom: '20px' }}>
        <label style={labelStyle}>Alert Threshold</label>
        <select style={{ ...inputStyle, width: '220px' }} defaultValue="all">
          <option value="all">All</option>
          <option value="critical">Critical Only</option>
          <option value="warning">Warning & Above</option>
        </select>
      </div>

      <div className="flex items-center justify-between" style={{ marginBottom: '16px' }}>
        <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Email Notifications</span>
        <Toggle on={email} onClick={() => setEmail((v) => !v)} />
      </div>

      <div className="flex items-center justify-between" style={{ marginBottom: '16px' }}>
        <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Browser Push</span>
        <Toggle on={push} onClick={() => setPush((v) => !v)} />
      </div>

      <div className="flex items-center justify-between" style={{ marginBottom: '8px' }}>
        <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Sound</span>
        <Toggle on={sound} onClick={() => setSound((v) => !v)} />
      </div>
      {sound && (
        <input type="range" min={0} max={100} defaultValue={70} className="w-full" style={{ accentColor: '#C8A434' }} />
      )}
    </div>
  )
}

function DataBackupSection() {
  return (
    <div style={cardBase}>
      <h3 style={sectionTitle}>Data & Backup</h3>
      <div className="flex flex-col gap-3" style={{ maxWidth: '320px' }}>
        <div className="flex items-center justify-between">
          <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Export Bookmarks (JSON)</span>
          <GoldButton><Download size={13} /> Export</GoldButton>
        </div>
        <div className="flex items-center justify-between">
          <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Import Bookmarks (JSON)</span>
          <GoldButton><Upload size={13} /> Import</GoldButton>
        </div>
        <div className="flex items-center justify-between">
          <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Export Settings</span>
          <GoldButton><Download size={13} /> Export</GoldButton>
        </div>
        <div className="border-t" style={{ borderColor: 'rgba(231,76,60,0.15)', margin: '8px 0' }} />
        <div className="flex items-center justify-between">
          <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Clear Cache</span>
          <GoldButton danger><Trash2 size={13} /> Clear</GoldButton>
        </div>
        <div className="flex items-center justify-between">
          <span style={{ fontSize: '13px', color: '#E8E6E0' }}>Reset to Defaults</span>
          <GoldButton danger><RotateCcw size={13} /> Reset</GoldButton>
        </div>
      </div>
    </div>
  )
}

function AboutSection() {
  const rows: [string, string][] = [
    ['App', 'ArchNest Dashboard v1.0.0'],
    ['Author', 'Samuel James'],
    ['Repo', 'github.com/SamuelSJames/archnest'],
    ['Stack', 'React 19, Vite, TypeScript'],
    ['License', 'MIT'],
  ]
  return (
    <div style={cardBase}>
      <h3 style={sectionTitle}>About</h3>
      <div className="flex flex-col gap-3">
        {rows.map(([label, value]) => (
          <div key={label} className="flex items-center justify-between">
            <span style={{ fontSize: '12px', color: '#7A7D85' }}>{label}</span>
            <span style={{ fontSize: '12px', color: '#E8E6E0' }}>{value}</span>
          </div>
        ))}
      </div>
    </div>
  )
}

const sectionComponents: Record<string, () => JSX.Element> = {
  profile: ProfileSection,
  appearance: AppearanceSection,
  integrations: IntegrationsSection,
  notifications: NotificationsSection,
  data: DataBackupSection,
  about: AboutSection,
}

export default function Settings() {
  const [active, setActive] = useState('profile')
  const ActiveSection = sectionComponents[active]

  return (
    <div className="flex h-full w-full gap-5">
      {/* Settings nav */}
      <div className="flex flex-col gap-1 shrink-0" style={{ width: '200px' }}>
        {navSections.map((s) => {
          const Icon = s.icon
          const isActive = active === s.id
          return (
            <button
              key={s.id}
              onClick={() => setActive(s.id)}
              className="flex items-center gap-2.5 cursor-pointer border-none bg-transparent transition-colors"
              style={{
                fontSize: '13px',
                fontWeight: 500,
                padding: '10px 14px',
                borderRadius: '8px',
                color: isActive ? '#C8A434' : '#7A7D85',
                backgroundColor: isActive ? 'rgba(200,164,52,0.1)' : 'transparent',
              }}
            >
              <Icon size={15} />
              {s.label}
            </button>
          )
        })}
      </div>

      {/* Content */}
      <div className="flex-1 overflow-y-auto" style={{ scrollbarWidth: 'none' }}>
        <ActiveSection />
      </div>
    </div>
  )
}