import { useNostrAuth } from '@/hooks/useNostrAuth'
import { ConnectedUserMenu } from './ConnectedUserMenu'
import { RecoveryStep } from './CreateAccountModalSteps'
import { UnlockAccountModal } from './UnlockAccountModal'
import type { NostrProfile } from '@/types/nostr'
import { Button } from './ui'
import { t } from '@/lib/i18n'
import { getConnectButtonMode } from './connectButton/connectButtonMode'
import { useAutoConnect, useConnectButtonUiState } from './connectButton/useConnectButtonUiState'

function ConnectForm({
  onCreateAccount,
  onUnlock,
  loading,
  error,
}: {
  onCreateAccount: () => void
  onUnlock: () => void
  loading: boolean
  error: string | null
}): React.ReactElement {
  return (
    <div className="flex flex-col gap-2">
      <Button
        variant="primary"
        onClick={onCreateAccount}
        disabled={loading}
        size="large"
      >
        {t('connect.createAccount')}
      </Button>
      <Button
        variant="secondary"
        onClick={onUnlock}
        disabled={loading}
        size="large"
      >
        {t('connect.connect')}
      </Button>
      {error && <p className="text-sm text-red-400">{error}</p>}
    </div>
  )
}

function ConnectedState({ pubkey, profile, loading, disconnect }: { pubkey: string; profile: NostrProfile | null; loading: boolean; disconnect: () => Promise<void> }): React.ReactElement {
  return (
    <ConnectedUserMenu
      pubkey={pubkey}
      profile={profile}
      onDisconnect={() => {
        void disconnect()
      }}
      loading={loading}
    />
  )
}

function UnlockState({ loading, error, onUnlock, onClose }: { loading: boolean; error: string | null; onUnlock: () => void; onClose: () => void }): React.ReactElement {
  return (
    <>
      <ConnectForm
        onCreateAccount={noop}
        onUnlock={onUnlock}
        loading={loading}
        error={error}
      />
      <UnlockAccountModal onSuccess={onClose} onClose={onClose} />
    </>
  )
}

function noop(): void {
  // Intentionally empty: UnlockState must render ConnectForm but "create account" is not available in this mode.
}


function DisconnectedState({
  loading,
  error,
  showUnlockModal,
  setShowUnlockModal,
  onCreateAccount,
}: {
  loading: boolean
  error: string | null
  showUnlockModal: boolean
  setShowUnlockModal: (show: boolean) => void
  onCreateAccount: () => void
}): React.ReactElement {
  return (
    <>
      <ConnectForm
        onCreateAccount={onCreateAccount}
        onUnlock={() => setShowUnlockModal(true)}
        loading={loading}
        error={error}
      />
      {showUnlockModal && (
        <UnlockAccountModal
          onSuccess={() => setShowUnlockModal(false)}
          onClose={() => setShowUnlockModal(false)}
        />
      )}
    </>
  )
}

export function ConnectButton(): React.ReactElement {
  const { connected, pubkey, profile, loading, error, connect, disconnect, accountExists, isUnlocked } = useNostrAuth()
  const ui = useConnectButtonUiState()

  useAutoConnect({
    accountExists,
    pubkey,
    showRecoveryStep: ui.showRecoveryStep,
    showUnlockModal: ui.showUnlockModal,
    connect,
  })

  const mode = getConnectButtonMode({
    connected,
    pubkey,
    isUnlocked,
    accountExists,
    showUnlockModal: ui.showUnlockModal,
  })

  if (mode === 'connected') {
    return <ConnectedState pubkey={requirePubkey(pubkey)} profile={profile} loading={loading} disconnect={disconnect} />
  }

  if (mode === 'unlock_required') {
    return <UnlockState loading={loading} error={error} onUnlock={ui.openUnlockModal} onClose={ui.closeUnlockModal} />
  }

  return (
    <>
      <DisconnectedState
        loading={loading ?? ui.creatingAccount}
        error={error ?? ui.createError}
        showUnlockModal={ui.showUnlockModal}
        setShowUnlockModal={ui.setShowUnlockModal}
        onCreateAccount={ui.onCreateAccount}
      />
      {ui.showRecoveryStep && (
        <RecoveryStep recoveryPhrase={ui.recoveryPhrase} npub={ui.npub} onContinue={ui.onRecoveryContinue} />
      )}
      {ui.showUnlockModal && <UnlockAccountModal onSuccess={ui.onUnlockSuccess} onClose={ui.closeUnlockModal} />}
    </>
  )
}

function requirePubkey(pubkey: string | null): string {
  if (!pubkey) {
    const error = new Error('Invariant violation: pubkey is required when ConnectButton mode is "connected"')
    console.error(error.message, { pubkey })
    throw error
  }
  return pubkey
}