'use client'

import Link from 'next/link'
import { usePathname } from 'next/navigation'
import { HugeiconsIcon } from '@hugeicons/react'
import { ChevronRightIcon, UserIcon } from '@hugeicons/core-free-icons'

import {
  Sidebar,
  SidebarContent,
  SidebarFooter,
  SidebarGroup,
  SidebarHeader,
  SidebarMenu,
  SidebarMenuButton,
  SidebarMenuItem,
  SidebarMenuSub,
  SidebarMenuSubButton,
  SidebarMenuSubItem,
  SidebarRail,
} from '@/components/ui/sidebar'
import {
  Collapsible,
  CollapsibleContent,
  CollapsibleTrigger,
} from '@/components/ui/collapsible'
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from '@/components/ui/select'
import { useAuth, type Role } from '@/contexts/auth-context'
import { DASHBOARD_ITEM, NAV_GROUPS, type NavGroup, type NavItem } from '@/config/nav'

function canSee(item: NavItem, permissions: string[]): boolean {
  if (!item.permission) return true
  return permissions.includes('*') || permissions.includes(item.permission)
}

function isGroupVisible(group: NavGroup, permissions: string[]): boolean {
  return group.items.some((item) => canSee(item, permissions))
}

export function AppSidebar() {
  const { user, setRole, permissions } = useAuth()
  const pathname = usePathname()

  const dashboardActive = pathname === DASHBOARD_ITEM.href

  return (
    <Sidebar collapsible="icon">
      <SidebarHeader>
        <div className="flex items-center gap-2 px-2 py-1">
          <div className="flex h-8 w-8 shrink-0 items-center justify-center rounded-lg bg-primary text-primary-foreground text-sm font-bold">
            D
          </div>
          <span className="truncate font-semibold text-sidebar-foreground group-data-[collapsible=icon]:hidden">
            Distribution
          </span>
        </div>
      </SidebarHeader>

      <SidebarContent className="gap-0">
        {/* Dashboard — standalone, not inside a collapsible group */}
        <SidebarGroup className="py-1">
          <SidebarMenu>
            <SidebarMenuItem>
              <SidebarMenuButton
                render={<Link href={DASHBOARD_ITEM.href} />}
                isActive={dashboardActive}
                tooltip={DASHBOARD_ITEM.title}
              >
                <HugeiconsIcon icon={DASHBOARD_ITEM.icon} size={18} />
                <span>{DASHBOARD_ITEM.title}</span>
              </SidebarMenuButton>
            </SidebarMenuItem>
          </SidebarMenu>
        </SidebarGroup>

        {/* Collapsible groups */}
        {NAV_GROUPS.map((group) => {
          if (!isGroupVisible(group, permissions)) return null

          const visibleItems = group.items.filter((item) =>
            canSee(item, permissions),
          )
          const groupActive = visibleItems.some(
            (item) =>
              pathname === item.href ||
              (item.href !== '/' && pathname.startsWith(item.href)),
          )

          return (
            <Collapsible
              key={group.title}
              defaultOpen={false}
              className="group/collapsible"
            >
              <SidebarGroup className="py-0">
                <SidebarMenu>
                  {/* Group trigger — looks like a regular nav button */}
                  <SidebarMenuItem>
                    <SidebarMenuButton
                      render={<CollapsibleTrigger />}
                      isActive={groupActive}
                      tooltip={group.title}
                    >
                      <HugeiconsIcon icon={group.icon} size={18} />
                      <span>{group.title}</span>
                      <HugeiconsIcon
                        icon={ChevronRightIcon}
                        size={14}
                        className="ml-auto shrink-0 transition-transform duration-200 group-data-[open]/collapsible:rotate-90 group-data-[collapsible=icon]:hidden"
                      />
                    </SidebarMenuButton>
                  </SidebarMenuItem>

                  {/* Sub-items with indent line */}
                  <CollapsibleContent>
                    <SidebarMenuSub>
                      {visibleItems.map((item) => {
                        const isActive =
                          pathname === item.href ||
                          (item.href !== '/' &&
                            pathname.startsWith(item.href))
                        return (
                          <SidebarMenuSubItem key={item.href}>
                            <SidebarMenuSubButton
                              render={<Link href={item.href} />}
                              isActive={isActive}
                            >
                              <HugeiconsIcon icon={item.icon} size={15} />
                              <span>{item.title}</span>
                            </SidebarMenuSubButton>
                          </SidebarMenuSubItem>
                        )
                      })}
                    </SidebarMenuSub>
                  </CollapsibleContent>
                </SidebarMenu>
              </SidebarGroup>
            </Collapsible>
          )
        })}
      </SidebarContent>

      <SidebarFooter>
        <div className="flex items-center gap-2 px-2 py-1 group-data-[collapsible=icon]:justify-center">
          <div className="flex h-8 w-8 shrink-0 items-center justify-center rounded-full bg-muted text-muted-foreground">
            <HugeiconsIcon icon={UserIcon} size={16} />
          </div>
          <div className="flex min-w-0 flex-1 flex-col group-data-[collapsible=icon]:hidden">
            <span className="truncate text-sm font-medium text-sidebar-foreground">
              {user.fullName}
            </span>
            <Select value={user.role} onValueChange={(v) => setRole(v as Role)}>
              <SelectTrigger className="h-5 border-0 p-0 text-xs text-muted-foreground shadow-none focus:ring-0">
                <SelectValue />
              </SelectTrigger>
              <SelectContent>
                <SelectItem value="admin">Admin</SelectItem>
                <SelectItem value="warehouse">Warehouse</SelectItem>
                <SelectItem value="sales">Sales</SelectItem>
              </SelectContent>
            </Select>
          </div>
        </div>
      </SidebarFooter>

      <SidebarRail />
    </Sidebar>
  )
}