'use client'

import { useState, useEffect } from 'react'
import { X, Download, ExternalLink, AlertCircle, ShoppingCart } from 'lucide-react'
import { Button } from '@/components/ui/button'
import {
  Dialog,
  DialogContent,
  DialogHeader,
  DialogDescription,
  DialogTitle,
  DialogClose,
} from '@/components/ui/dialog'
import {
  Sheet,
  SheetContent,
  SheetHeader,
  SheetTitle,
} from '@/components/ui/sheet'
import { PartsPanel } from '@/components/parts-panel'
import { useIsMobile } from '@/hooks/use-mobile'

interface ManualViewerProps {
  manualUrl: string
  filename: string
  isOpen: boolean
  onClose: () => void
}

export function ManualViewer({ manualUrl, filename, isOpen, onClose }: ManualViewerProps) {
  const [pdfError, setPdfError] = useState(false)
  const [isLoading, setIsLoading] = useState(true)
  const [showPartsPanel, setShowPartsPanel] = useState(true)
  const isMobile = useIsMobile()

  // Reset error state when manual URL changes
  useEffect(() => {
    if (isOpen) {
      setPdfError(false)
      setIsLoading(true)
    }
  }, [manualUrl, isOpen])

  // The URL is already properly encoded in getManualUrl function
  // Just use it as-is for the iframe src
  const encodedUrl = manualUrl

  const handleIframeLoad = () => {
    setIsLoading(false)
  }

  const handleIframeError = () => {
    setIsLoading(false)
    setPdfError(true)
  }

  // Mobile layout - use Sheet
  if (isMobile) {
    return (
      <Sheet open={isOpen} onOpenChange={onClose}>
        <SheetContent side="bottom" className="h-screen max-h-screen flex flex-col p-0 gap-0 [&>button]:hidden">
          <SheetHeader className="px-4 pt-4 pb-3 border-b flex-shrink-0">
            <div className="flex items-center justify-between gap-2">
              <SheetTitle className="text-base font-semibold line-clamp-1 flex-1 min-w-0">
                {filename.replace(/\.pdf$/i, '')}
              </SheetTitle>
              <div className="flex items-center gap-1 flex-shrink-0">
                <Button
                  variant="outline"
                  size="sm"
                  onClick={() => {
                    const link = document.createElement('a')
                    link.href = encodedUrl
                    link.download = filename
                    link.click()
                  }}
                  className="h-8 px-2"
                >
                  <Download className="h-4 w-4" />
                </Button>
                <Button
                  variant="ghost"
                  size="sm"
                  onClick={onClose}
                  className="h-8 px-2"
                >
                  <X className="h-4 w-4" />
                </Button>
              </div>
            </div>
          </SheetHeader>
          <div className="flex-1 overflow-hidden min-h-0 relative bg-muted/50">
            {isLoading && !pdfError && (
              <div className="absolute inset-0 flex items-center justify-center bg-background/80 z-10">
                <div className="text-center">
                  <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-primary mx-auto mb-2"></div>
                  <p className="text-sm text-muted-foreground">Loading PDF...</p>
                </div>
              </div>
            )}
            {pdfError ? (
              <div className="absolute inset-0 flex items-center justify-center bg-background z-10 p-4">
                <div className="text-center max-w-md">
                  <AlertCircle className="h-12 w-12 text-destructive mx-auto mb-4" />
                  <h3 className="text-lg font-semibold mb-2">Unable to Load PDF</h3>
                  <p className="text-sm text-muted-foreground mb-4">
                    The PDF file could not be loaded. This may be due to file corruption or an encoding issue.
                  </p>
                  <div className="flex flex-col gap-2">
                    <Button
                      variant="outline"
                      onClick={() => window.open(encodedUrl, '_blank')}
                      className="w-full"
                    >
                      <ExternalLink className="h-4 w-4 mr-2" />
                      Try Opening in New Tab
                    </Button>
                    <Button
                      variant="outline"
                      onClick={() => {
                        const link = document.createElement('a')
                        link.href = encodedUrl
                        link.download = filename
                        link.click()
                      }}
                      className="w-full"
                    >
                      <Download className="h-4 w-4 mr-2" />
                      Download Instead
                    </Button>
                  </div>
                </div>
              </div>
            ) : (
              <iframe
                src={`${encodedUrl}#toolbar=1&navpanes=0&scrollbar=1`}
                className="w-full h-full border-0 min-h-full block"
                title={filename}
                onLoad={handleIframeLoad}
                onError={handleIframeError}
              />
            )}
          </div>
        </SheetContent>
      </Sheet>
    )
  }

  // Desktop layout - use Dialog
  return (
    <Dialog open={isOpen} onOpenChange={onClose}>
      <DialogContent 
        className="!max-w-none !w-screen !h-screen !max-h-screen p-0 flex flex-col gap-0 !m-0 !rounded-none !border-0 !translate-x-0 !translate-y-0 !top-0 !left-0 !right-0 !bottom-0 !inset-0"
        showCloseButton={false}
        style={{
          position: 'fixed',
          top: 0,
          left: 0,
          right: 0,
          bottom: 0,
          width: '100vw',
          height: '100vh',
          maxWidth: '100vw',
          maxHeight: '100vh',
          transform: 'none',
          margin: 0,
          borderRadius: 0,
          border: 'none',
        }}
      >
        <DialogHeader className="px-4 sm:px-6 pt-4 sm:pt-6 pb-3 sm:pb-4 border-b flex-shrink-0 bg-background">
          <DialogDescription className="sr-only">
            PDF viewer for {filename.replace(/\.pdf$/i, '')}. Use the actions to open the manual in a new tab,
            download it, or browse available parts.
          </DialogDescription>
          <div className="flex items-center justify-between gap-4">
            <DialogTitle className="text-base sm:text-lg font-semibold line-clamp-1 flex-1 min-w-0">
              {filename.replace(/\.pdf$/i, '')}
            </DialogTitle>
            <div className="flex items-center gap-2 flex-shrink-0">
              <Button
                variant="outline"
                size="sm"
                onClick={() => setShowPartsPanel(!showPartsPanel)}
              >
                <ShoppingCart className="h-4 w-4 mr-1" />
                {showPartsPanel ? 'Hide' : 'Show'} Parts
              </Button>
              <Button
                variant="outline"
                size="sm"
                onClick={() => window.open(encodedUrl, '_blank')}
              >
                <ExternalLink className="h-4 w-4 mr-1" />
                Open in New Tab
              </Button>
              <Button
                variant="outline"
                size="sm"
                onClick={() => {
                  const link = document.createElement('a')
                  link.href = encodedUrl
                  link.download = filename
                  link.click()
                }}
              >
                <Download className="h-4 w-4 mr-1" />
                Download
              </Button>
              <DialogClose asChild>
                <Button variant="ghost" size="sm" className="flex-shrink-0">
                  <X className="h-4 w-4" />
                </Button>
              </DialogClose>
            </div>
          </div>
        </DialogHeader>
        <div className="flex-1 overflow-hidden min-h-0 relative bg-muted/50 flex flex-row w-full">
          {/* PDF Viewer - responsive width based on parts panel */}
          <div 
            className={`overflow-hidden min-h-0 relative transition-all duration-300 h-full ${
              showPartsPanel ? 'w-[75%] lg:w-[80%]' : 'w-full'
            }`}
          >
            {isLoading && !pdfError && (
              <div className="absolute inset-0 flex items-center justify-center bg-background/80 z-10">
                <div className="text-center">
                  <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-primary mx-auto mb-2"></div>
                  <p className="text-sm text-muted-foreground">Loading PDF...</p>
                </div>
              </div>
            )}
            {pdfError ? (
              <div className="absolute inset-0 flex items-center justify-center bg-background z-10">
                <div className="text-center p-6 max-w-md">
                  <AlertCircle className="h-12 w-12 text-destructive mx-auto mb-4" />
                  <h3 className="text-lg font-semibold mb-2">Unable to Load PDF</h3>
                  <p className="text-sm text-muted-foreground mb-4">
                    The PDF file could not be loaded. This may be due to file corruption or an encoding issue.
                  </p>
                  <div className="flex gap-2 justify-center">
                    <Button
                      variant="outline"
                      onClick={() => window.open(encodedUrl, '_blank')}
                    >
                      <ExternalLink className="h-4 w-4 mr-2" />
                      Try Opening in New Tab
                    </Button>
                    <Button
                      variant="outline"
                      onClick={() => {
                        const link = document.createElement('a')
                        link.href = encodedUrl
                        link.download = filename
                        link.click()
                      }}
                    >
                      <Download className="h-4 w-4 mr-2" />
                      Download Instead
                    </Button>
                  </div>
                </div>
              </div>
            ) : (
              <iframe
                src={`${encodedUrl}#toolbar=1&navpanes=0&scrollbar=1`}
                className="w-full h-full border-0 min-h-full block"
                title={filename}
                onLoad={handleIframeLoad}
                onError={handleIframeError}
              />
            )}
          </div>
          {/* Parts Panel - right side, responsive width */}
          {showPartsPanel && (
            <PartsPanel 
              manualFilename={filename} 
              className={`border-l border-yellow-300/20 bg-yellow-50 dark:bg-yellow-950/90 overflow-y-auto h-full ${
                'w-[25%] lg:w-[20%]'
              }`}
            />
          )}
        </div>
      </DialogContent>
    </Dialog>
  )
}