import { Link, useLocation, useNavigate } from '@tanstack/react-router'
import {
  AppShell,
  Avatar,
  Burger,
  Group,
  Menu,
  NavLink,
  Stack,
  Text,
  UnstyledButton,
} from '@pikku/mantine/core'
import { useDisclosure } from '@mantine/hooks'
import { useQueryClient } from '@tanstack/react-query'
import { m, mKey } from '@/i18n/messages'
import { useLocale } from '@/i18n/config'
import { asI18n } from '@pikku/react'
import { createContext, useContext, useEffect, useState } from 'react'
import { Building2, LayoutDashboard } from 'lucide-react'

const PageTitleContext = createContext<((title: string | undefined) => void) | null>(null)

export function PageTitle({ title }: { title: string }) {
  usePageTitle(title)
  return null
}

export function usePageTitle(title: string | undefined) {
  const setTitle = useContext(PageTitleContext)
  useEffect(() => {
    if (!setTitle) return
    setTitle(title)
    return () => setTitle(undefined)
  }, [setTitle, title])
}

const NAV_ITEMS = [
  { to: '/companies', labelKey: 'common.nav.items.companies', Icon: Building2 },
  { to: '/portfolio', labelKey: 'common.nav.items.portfolio', Icon: LayoutDashboard },
] as const

const initials = (name: string) =>
  name
    .split(/\s+/)
    .filter(Boolean)
    .slice(0, 2)
    .map((p) => p[0]?.toUpperCase() ?? '')
    .join('')

function QSeal() {
  return (
    <span style={{
      display: 'inline-flex', alignItems: 'center', justifyContent: 'center',
      width: 26, height: 26, borderRadius: 6, background: '#1F5641',
      color: '#FBFAF7', fontFamily: "'Source Serif 4', Georgia, serif",
      fontWeight: 600, fontSize: 15, lineHeight: 1, flexShrink: 0,
    }}>
      Q
    </span>
  )
}

export function AppLayout({
  user,
  children,
}: {
  user: { userId: string; email: string; displayName: string }
  children: React.ReactNode
}) {
  useLocale()
  const [opened, { toggle, close }] = useDisclosure()
  const [pageTitle, setPageTitle] = useState<string | undefined>(undefined)
  const location = useLocation()
  const navigate = useNavigate()
  const qc = useQueryClient()

  const API_URL = import.meta.env.VITE_API_URL ?? 'http://localhost:4003'

  const handleLogout = async () => {
    try {
      const csrfRes = await fetch(`${API_URL}/auth/csrf`, { credentials: 'include' })
      const { csrfToken } = (await csrfRes.json()) as { csrfToken: string }
      const body = new URLSearchParams({ csrfToken, callbackUrl: '/login' })
      await fetch(`${API_URL}/auth/signout`, {
        method: 'POST',
        headers: { 'content-type': 'application/x-www-form-urlencoded' },
        body,
        credentials: 'include',
        redirect: 'manual',
      })
      qc.clear()
      navigate({ to: '/login' })
    } catch {
      navigate({ to: '/logout' })
    }
  }

  return (
    <PageTitleContext.Provider value={setPageTitle}>
      <AppShell
        header={{ height: 64 }}
        navbar={{ width: 248, breakpoint: 'sm', collapsed: { mobile: !opened } }}
        padding={{ base: 'md', md: 'xl' }}
        styles={{
          header: { borderBottom: '1px solid #E6E3DB', background: '#fff' },
          navbar: { borderRight: '1px solid #E6E3DB', background: '#fff' },
        }}
      >
        <AppShell.Header>
          <Group h="100%" px={0} justify="space-between" wrap="nowrap">
            {/* Logo area matches sidebar width */}
            <Group
              gap={11}
              style={{
                width: 248, flexShrink: 0, padding: '0 22px',
                borderRight: '1px solid #EFEDE6', height: '100%',
              }}
            >
              <Burger
                opened={opened}
                onClick={toggle}
                hiddenFrom="sm"
                size="sm"
                aria-label={m.common_nav_toggle()}
              />
              <Link to="/" style={{ textDecoration: 'none', display: 'flex', alignItems: 'center', gap: 11 }} onClick={close}>
                <QSeal />
                <Text style={{ fontFamily: "'Source Serif 4', Georgia, serif", fontSize: 17, fontWeight: 600, color: '#16201B' }}>
                  {m.common_brand_name()}
                </Text>
              </Link>
            </Group>

            {/* Right: breadcrumb + user */}
            <Group justify="space-between" style={{ flex: 1, padding: '0 26px' }}>
              <Group gap={12}>
                {pageTitle && (
                  <>
                    <Text style={{ color: '#A9B0A6', fontFamily: "'IBM Plex Mono', monospace", fontSize: 12 }}>
                      {m.common_brand_name()}
                    </Text>
                    <span style={{ color: '#D8D3C8' }}>/</span>
                    <Text fw={600} size="sm" visibleFrom="sm" style={{ color: '#16201B' }}>
                      {asI18n(pageTitle ?? '')}
                    </Text>
                  </>
                )}
              </Group>
              <Menu position="bottom-end" withArrow shadow="sm">
                <Menu.Target>
                  <UnstyledButton style={{ display: 'flex', alignItems: 'center', gap: 10, padding: '4px 8px', borderRadius: 8 }}>
                    <Stack gap={0} align="flex-end" visibleFrom="sm">
                      <Text size="sm" fw={600} style={{ lineHeight: 1.2, color: '#16201B' }}>{asI18n(user.displayName)}</Text>
                      <Text size="xs" style={{ lineHeight: 1.2, color: '#A9B0A6', fontFamily: "'IBM Plex Mono', monospace" }}>{asI18n(user.email)}</Text>
                    </Stack>
                    <Avatar radius="xl" color="quorum" variant="light" size={34}>
                      {asI18n(initials(user.displayName))}
                    </Avatar>
                  </UnstyledButton>
                </Menu.Target>
                <Menu.Dropdown>
                  <Menu.Label>{asI18n(user.email)}</Menu.Label>
                  <Menu.Divider />
                  <Menu.Item color="red" onClick={handleLogout}>
                    {m.common_nav_logout()}
                  </Menu.Item>
                </Menu.Dropdown>
              </Menu>
            </Group>
          </Group>
        </AppShell.Header>

        <AppShell.Navbar p="md">
          <AppShell.Section grow>
            <p style={{
              color: '#A9B0A6', fontFamily: "'IBM Plex Mono', monospace",
              letterSpacing: '.06em', textTransform: 'uppercase', fontSize: 9,
              padding: '0 10px', marginBottom: 10, margin: '0 0 10px 0',
            }}>
              Workspace
            </p>
            <Stack gap={4}>
              {NAV_ITEMS.map(({ to, labelKey, Icon }) => (
                <NavLink
                  key={to}
                  component={Link}
                  to={to}
                  label={mKey(labelKey)}
                  leftSection={<Icon size={16} />}
                  active={location.pathname.startsWith(to)}
                  onClick={close}
                />
              ))}
            </Stack>
          </AppShell.Section>
          <AppShell.Section pt="md" style={{ borderTop: '1px solid #EFEDE6' }}>
            <Text style={{ color: '#B7BDB6', fontFamily: "'IBM Plex Mono', monospace", lineHeight: 1.6, fontSize: 10 }}>
              {m.common_brand_tagline()}
            </Text>
          </AppShell.Section>
        </AppShell.Navbar>

        <AppShell.Main style={{ background: '#FBFAF7' }}>{children}</AppShell.Main>
      </AppShell>
    </PageTitleContext.Provider>
  )
}