'use client'

import { FlaskConical, Plus, ChevronDown, Trash2, Layout } from 'lucide-react'
import { Button } from '@/components/ui/button'
import { renameCanvas, deleteCanvas, createCanvas } from '@/app/actions/canvas-actions'
import { useRouter } from 'next/navigation'
import { useState, useTransition } from 'react'
import {
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuItem,
  DropdownMenuLabel,
  DropdownMenuSeparator,
  DropdownMenuTrigger,
} from "@/components/ui/dropdown-menu"
import { cn } from '@/lib/utils'
import { toast } from 'sonner'
import { useLanguage } from '@/lib/i18n'

interface LabHeaderProps {
  canvases: any[]
  currentCanvasId: string | null
  onCreateCanvas: () => Promise<void>
}

export function LabHeader({ canvases, currentCanvasId, onCreateCanvas }: LabHeaderProps) {
  const router = useRouter()
  const { t, language } = useLanguage()
  const [isPending, startTransition] = useTransition()
  const [isEditing, setIsEditing] = useState(false)
  
  const currentCanvas = canvases.find(c => c.id === currentCanvasId)

  const handleRename = async (id: string, newName: string) => {
    if (!newName || newName === currentCanvas?.name) {
      setIsEditing(false)
      return
    }

    try {
      await renameCanvas(id, newName)
      toast.success(t('labHeader.renamed'))
      router.refresh()
    } catch (e) {
      toast.error(t('labHeader.renameError'))
    }
    setIsEditing(false)
  }

  const handleCreate = async () => {
    startTransition(async () => {
      try {
        const newCanvas = await createCanvas(language)
        router.push(`/lab?id=${newCanvas.id}`)
        toast.success(t('labHeader.created'))
      } catch (e) {
        toast.error(t('labHeader.createFailed'))
      }
    })
  }

  const handleDelete = async (id: string, name: string) => {
    if (window.confirm(`${t('labHeader.deleteSpace')} "${name}" ?`)) {
      try {
        await deleteCanvas(id)
        toast.success(t('labHeader.deleted'))
        router.push('/lab')
        router.refresh()
      } catch (e) {
        toast.error(t('labHeader.deleteError'))
      }
    }
  }

  return (
    <header className="h-16 border-b bg-white/80 dark:bg-[#1a1c22]/80 backdrop-blur-md flex items-center justify-between px-6 z-20 shrink-0 sticky top-0">
      <div className="flex items-center gap-4">
        <div className="flex items-center gap-2 pe-4 border-e">
          <div className="p-2 bg-primary/10 rounded-xl">
            <FlaskConical className="h-4 w-4 text-primary" />
          </div>
          <div>
            <h1 className="text-sm font-bold tracking-tight">{t('labHeader.title')}</h1>
            <div className="flex items-center gap-1.5">
              <span className="w-1.5 h-1.5 rounded-full bg-green-500 animate-pulse" />
              <p className="text-[10px] text-muted-foreground uppercase tracking-widest font-semibold">{t('labHeader.live')}</p>
            </div>
          </div>
        </div>

        {/* Project Switcher */}
        <DropdownMenu>
          <DropdownMenuTrigger asChild>
            <Button variant="ghost" className="h-10 flex items-center gap-2 hover:bg-muted/50 rounded-xl px-3 transition-all active:scale-95">
              <Layout className="h-4 w-4 text-muted-foreground" />
              <div className="flex flex-col items-start gap-0.5">
                <span className="text-[10px] text-muted-foreground uppercase font-bold leading-none">{t('labHeader.currentProject')}</span>
                <span className="text-sm font-semibold truncate max-w-[150px]">{currentCanvas?.name || t('labHeader.choose')}</span>
              </div>
              <ChevronDown className="h-4 w-4 text-muted-foreground ms-2" />
            </Button>
          </DropdownMenuTrigger>
          <DropdownMenuContent align="start" className="w-[280px] p-2 rounded-2xl shadow-xl border-border/40 bg-paper dark:bg-dark-paper">
            <DropdownMenuLabel className="text-xs text-muted-foreground px-2 py-1.5 flex justify-between items-center">
              {t('labHeader.yourSpaces')}
              <span className="text-[10px] bg-brand-accent/10 text-brand-accent px-1.5 py-0.5 rounded-full font-mono">{canvases.length}</span>
            </DropdownMenuLabel>
            <div className="space-y-1 mt-1">
              {canvases.map(c => (
                <div key={c.id} className="group/item flex items-center gap-1">
                  <DropdownMenuItem 
                    className={cn(
                      "flex-1 flex flex-col items-start gap-0.5 rounded-xl cursor-pointer p-3 transition-all",
                      c.id === currentCanvasId ? "bg-brand-accent/5 text-brand-accent border border-brand-accent/20" : "hover:bg-muted/50"
                    )}
                    onClick={() => router.push(`/lab?id=${c.id}`)}
                  >
                    <div className="flex items-center gap-2 w-full justify-between">
                      <span className="font-semibold text-sm">{c.name}</span>
                      {c.id === currentCanvasId && <span className="w-2 h-2 rounded-full bg-brand-accent" />}
                    </div>
                    <span className="text-[10px] text-muted-foreground">{t('labHeader.updated')} {new Date(c.updatedAt).toLocaleDateString()}</span>
                  </DropdownMenuItem>
                  <Button
                    variant="ghost"
                    size="icon"
                    className="h-8 w-8 opacity-0 group-hover/item:opacity-100 transition-opacity hover:text-destructive hover:bg-destructive/10"
                    onClick={(e) => {
                      e.stopPropagation()
                      handleDelete(c.id, c.name)
                    }}
                  >
                    <Trash2 className="h-3.5 w-3.5" />
                  </Button>
                </div>
              ))}
            </div>
            <DropdownMenuSeparator className="my-2" />
            <DropdownMenuItem 
              onClick={handleCreate}
              disabled={isPending}
              className="flex items-center gap-2 text-brand-accent font-medium p-3 rounded-xl cursor-pointer hover:bg-brand-accent/5"
            >
              <Plus className="h-4 w-4" />
              {t('labHeader.newSpace')}
            </DropdownMenuItem>
          </DropdownMenuContent>
        </DropdownMenu>

        {/* Inline Rename — click on project name to edit */}
        {currentCanvas && (
          <div className="ms-2 flex items-center gap-2">
            {isEditing ? (
              <input
                autoFocus
                className="bg-muted px-3 py-1.5 rounded-lg text-sm font-medium focus:ring-2 focus:ring-primary/20 outline-none w-[200px]"
                defaultValue={currentCanvas.name}
                onKeyDown={(e) => {
                  if (e.key === 'Enter') handleRename(currentCanvas.id, e.currentTarget.value)
                  if (e.key === 'Escape') setIsEditing(false)
                }}
                onBlur={(e) => handleRename(currentCanvas.id, e.target.value)}
              />
            ) : (
              <button
                onClick={() => setIsEditing(true)}
                className="text-sm font-semibold text-foreground hover:text-primary transition-colors"
                title={t('labHeader.rename') || 'Rename'}
              >
                {currentCanvas.name}
              </button>
            )}
          </div>
        )}
      </div>

      <div className="flex items-center gap-3">
        {currentCanvas && (
          <Button
            variant="ghost"
            size="icon"
            onClick={() => handleDelete(currentCanvas.id, currentCanvas.name)}
            className="text-muted-foreground hover:text-destructive hover:bg-destructive/5 rounded-xl transition-all"
          >
            <Trash2 className="h-4 w-4" />
          </Button>
        )}
      </div>
    </header>
  )
}
