import React, { useState, useEffect } from 'react';
import { Button } from '@/components/ui/button';
import { Textarea } from '@/components/ui/textarea';
import { MessageSquare, Loader2, AlertCircle } from 'lucide-react';
import { ASSET_REQUEST_CONFIG } from '@/types/asset-request';

interface CommentDialogProps {
  isOpen: boolean;
  onClose: () => void;
  onConfirm: (comments: string) => Promise<void>;
  requestId: number;
  employeeName: string;
}

const CommentDialog: React.FC<CommentDialogProps> = ({
  isOpen,
  onClose,
  onConfirm,
  requestId,
  employeeName,
}) => {
  const [comments, setComments] = useState('');
  const [isSubmitting, setIsSubmitting] = useState(false);
  const [error, setError] = useState('');

  // Reset state when dialog opens
  useEffect(() => {
    if (isOpen) {
      setComments('');
      setError('');
      setIsSubmitting(false);
    }
  }, [isOpen]);

  // Handle escape key and body scroll
  useEffect(() => {
    if (!isOpen) return;

    const handleEscape = (e: KeyboardEvent) => {
      if (e.key === 'Escape' && !isSubmitting) {
        onClose();
      }
    };

    document.addEventListener('keydown', handleEscape);
    document.body.style.overflow = 'hidden';

    return () => {
      document.removeEventListener('keydown', handleEscape);
      document.body.style.overflow = 'unset';
    };
  }, [isOpen, isSubmitting, onClose]);

  const handleSubmit = async () => {
    setError('');
    
    if (!comments.trim() || comments.trim().length < 5) {
      setError('Please provide at least 5 characters of comments');
      return;
    }

    setIsSubmitting(true);
    try {
      await onConfirm(comments.trim());
      onClose();
    } catch (err) {
      setError(err instanceof Error ? err.message : 'An error occurred');
    } finally {
      setIsSubmitting(false);
    }
  };

  const handleOverlayClick = (e: React.MouseEvent) => {
    if (!isSubmitting && e.target === e.currentTarget) {
      onClose();
    }
  };

  if (!isOpen) return null;

  return (
    <div 
      className="fixed inset-0 z-[999] flex items-center justify-center p-4 overflow-y-auto"
      role="dialog"
      aria-modal="true"
      aria-labelledby="dialog-title"
    >
      {/* Overlay */}
      <div 
        className="fixed inset-0 bg-black/80 backdrop-blur-sm transition-opacity"
        onClick={handleOverlayClick}
        aria-hidden="true"
      />
      
      {/* Modal Content */}
      <div 
        className="relative z-[1000] w-full max-w-md rounded-lg border bg-background shadow-lg animate-in fade-in-0 zoom-in-95 duration-200"
        onClick={(e) => e.stopPropagation()}
      >
        {/* Header */}
        <div className="flex items-start gap-3 p-6 border-b">
          <div className="p-2 rounded-full flex-shrink-0 bg-blue-100">
            <MessageSquare className="h-5 w-5 text-blue-600" />
          </div>
          <div className="flex-1 min-w-0">
            <h2 
              id="dialog-title" 
              className="text-lg font-semibold text-foreground"
            >
              Add Admin Comment
            </h2>
            <p className="text-sm text-muted-foreground mt-1">
              Add comments to request #{requestId} without changing its status
            </p>
          </div>
        </div>
        
        {/* Content */}
        <div className="p-6 space-y-4">
          {/* Request Info */}
          <div className="bg-muted rounded-md p-3 text-sm space-y-1">
            <div className="flex justify-between">
              <span className="text-muted-foreground">Request ID:</span>
              <span className="font-medium">#{requestId}</span>
            </div>
            <div className="flex justify-between">
              <span className="text-muted-foreground">Employee:</span>
              <span className="font-medium">{employeeName}</span>
            </div>
          </div>

          {/* Comments Input */}
          <div>
            <label htmlFor="comments" className="text-sm font-medium mb-2 block">
              Admin Comments
              <span className="text-destructive ml-1">*</span>
            </label>
            <Textarea
              id="comments"
              placeholder="Add your comments here (minimum 5 characters)..."
              value={comments}
              onChange={(e) => {
                setComments(e.target.value);
                setError('');
              }}
              maxLength={ASSET_REQUEST_CONFIG.MAX_ADMIN_COMMENTS_LENGTH}
              rows={4}
              className="resize-none w-full"
              disabled={isSubmitting}
              autoFocus
            />
            <div className="flex justify-between items-center mt-1">
              <div className="text-xs text-muted-foreground">
                {comments.length}/{ASSET_REQUEST_CONFIG.MAX_ADMIN_COMMENTS_LENGTH} characters
              </div>
              {error && (
                <div className="flex items-center gap-1 text-xs text-destructive">
                  <AlertCircle className="h-3 w-3" />
                  {error}
                </div>
              )}
            </div>
          </div>

          {/* Info Message */}
          <div className="bg-blue-50 border border-blue-200 rounded-md p-3 text-sm text-blue-800">
            <p>This will add your comments to the request without approving or rejecting it.</p>
          </div>

          {/* Action Buttons */}
          <div className="flex justify-end gap-3 pt-2">
            <Button
              type="button"
              variant="outline"
              onClick={onClose}
              disabled={isSubmitting}
            >
              Cancel
            </Button>
            <Button
              type="button"
              onClick={handleSubmit}
              disabled={
                isSubmitting ||
                !comments.trim() ||
                comments.trim().length < 5
              }
              className="bg-blue-600 hover:bg-blue-700 text-white"
            >
              {isSubmitting ? (
                <>
                  <Loader2 className="h-4 w-4 mr-2 animate-spin" />
                  Adding Comment...
                </>
              ) : (
                <>
                  <MessageSquare className="h-4 w-4 mr-2" />
                  Add Comment
                </>
              )}
            </Button>
          </div>
        </div>
      </div>
    </div>
  );
};

export default CommentDialog;