'use client'

import { useState } from 'react'
import { useRouter } from 'next/navigation'
import { updateItem, createItem } from '@/lib/actions'

interface ItemFormProps {
  listId: string
  item?: {
    id: string
    title: string
    description: string | null
    priority: string
    dueDate: Date | null
    tags: any
    notes: string | null
  }
  mode?: 'create' | 'edit'
}

export default function ItemForm({ listId, item, mode = 'edit' }: ItemFormProps) {
  const router = useRouter()
  const [isSubmitting, setIsSubmitting] = useState(false)
  const [errors, setErrors] = useState<Record<string, string>>({})

  // Form state
  const [title, setTitle] = useState(item?.title || '')
  const [description, setDescription] = useState(item?.description || '')
  const [priority, setPriority] = useState<'low' | 'medium' | 'high'>(
    (item?.priority as 'low' | 'medium' | 'high') || 'medium'
  )
  const [dueDate, setDueDate] = useState(
    item?.dueDate ? new Date(item.dueDate).toISOString().split('T')[0] : ''
  )
  const [tags, setTags] = useState<string[]>(
    Array.isArray(item?.tags) ? item.tags : []
  )
  const [tagInput, setTagInput] = useState('')
  const [notes, setNotes] = useState(item?.notes || '')

  const validateForm = () => {
    const newErrors: Record<string, string> = {}

    if (!title.trim()) {
      newErrors.title = 'Title is required'
    }

    if (title.length > 200) {
      newErrors.title = 'Title must be less than 200 characters'
    }

    setErrors(newErrors)
    return Object.keys(newErrors).length === 0
  }

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault()

    if (!validateForm()) {
      return
    }

    setIsSubmitting(true)

    try {
      const data = {
        title: title.trim(),
        description: description.trim() || null,
        priority,
        dueDate: dueDate ? new Date(dueDate) : null,
        tags,
        notes: notes.trim() || null,
      }

      if (mode === 'create') {
        await createItem(listId, data.title, data.description || undefined, {
          priority: data.priority,
          dueDate: data.dueDate,
          tags: data.tags,
          notes: data.notes,
        })
        router.push(`/list/${listId}`)
      } else if (item) {
        await updateItem(item.id, data)
        router.push(`/list/${listId}/item/${item.id}`)
      }
    } catch (error) {
      console.error('Error saving item:', error)
      setErrors({ submit: 'Failed to save item. Please try again.' })
    } finally {
      setIsSubmitting(false)
    }
  }

  const handleAddTag = () => {
    const tag = tagInput.trim()
    if (tag && !tags.includes(tag)) {
      setTags([...tags, tag])
      setTagInput('')
    }
  }

  const handleRemoveTag = (tagToRemove: string) => {
    setTags(tags.filter((tag) => tag !== tagToRemove))
  }

  const handleKeyDown = (e: React.KeyboardEvent) => {
    if (e.key === 'Enter') {
      e.preventDefault()
      handleAddTag()
    }
  }

  return (
    <form onSubmit={handleSubmit} className="space-y-6">
      {/* Title */}
      <div>
        <label htmlFor="title" className="block text-sm font-medium text-gray-700 mb-1">
          Title *
        </label>
        <input
          type="text"
          id="title"
          value={title}
          onChange={(e) => setTitle(e.target.value)}
          className={`w-full px-3 py-2 border rounded-lg focus:outline-none focus:ring-2 focus:ring-blue-500 ${
            errors.title ? 'border-red-500' : 'border-gray-300'
          }`}
          placeholder="Enter task title"
        />
        {errors.title && (
          <p className="mt-1 text-sm text-red-600">{errors.title}</p>
        )}
      </div>

      {/* Description */}
      <div>
        <label htmlFor="description" className="block text-sm font-medium text-gray-700 mb-1">
          Description
        </label>
        <textarea
          id="description"
          value={description}
          onChange={(e) => setDescription(e.target.value)}
          rows={3}
          className="w-full px-3 py-2 border border-gray-300 rounded-lg focus:outline-none focus:ring-2 focus:ring-blue-500"
          placeholder="Add a description"
        />
      </div>

      {/* Priority */}
      <div>
        <label htmlFor="priority" className="block text-sm font-medium text-gray-700 mb-1">
          Priority
        </label>
        <select
          id="priority"
          value={priority}
          onChange={(e) => setPriority(e.target.value as 'low' | 'medium' | 'high')}
          className="w-full px-3 py-2 border border-gray-300 rounded-lg focus:outline-none focus:ring-2 focus:ring-blue-500"
        >
          <option value="low">Low</option>
          <option value="medium">Medium</option>
          <option value="high">High</option>
        </select>
      </div>

      {/* Due Date */}
      <div>
        <label htmlFor="dueDate" className="block text-sm font-medium text-gray-700 mb-1">
          Due Date
        </label>
        <input
          type="date"
          id="dueDate"
          value={dueDate}
          onChange={(e) => setDueDate(e.target.value)}
          className="w-full px-3 py-2 border border-gray-300 rounded-lg focus:outline-none focus:ring-2 focus:ring-blue-500"
        />
      </div>

      {/* Tags */}
      <div>
        <label htmlFor="tags" className="block text-sm font-medium text-gray-700 mb-1">
          Tags
        </label>
        <div className="flex gap-2 mb-2">
          <input
            type="text"
            id="tags"
            value={tagInput}
            onChange={(e) => setTagInput(e.target.value)}
            onKeyDown={handleKeyDown}
            className="flex-1 px-3 py-2 border border-gray-300 rounded-lg focus:outline-none focus:ring-2 focus:ring-blue-500"
            placeholder="Add a tag"
          />
          <button
            type="button"
            onClick={handleAddTag}
            className="px-4 py-2 bg-gray-200 hover:bg-gray-300 text-gray-700 rounded-lg transition-colors"
          >
            Add
          </button>
        </div>
        {tags.length > 0 && (
          <div className="flex flex-wrap gap-2">
            {tags.map((tag) => (
              <span
                key={tag}
                className="inline-flex items-center gap-1 px-3 py-1 bg-blue-100 text-blue-800 rounded-full text-sm"
              >
                {tag}
                <button
                  type="button"
                  onClick={() => handleRemoveTag(tag)}
                  className="hover:text-blue-600"
                >
                  ×
                </button>
              </span>
            ))}
          </div>
        )}
      </div>

      {/* Notes */}
      <div>
        <label htmlFor="notes" className="block text-sm font-medium text-gray-700 mb-1">
          Notes
        </label>
        <textarea
          id="notes"
          value={notes}
          onChange={(e) => setNotes(e.target.value)}
          rows={5}
          className="w-full px-3 py-2 border border-gray-300 rounded-lg focus:outline-none focus:ring-2 focus:ring-blue-500"
          placeholder="Add additional notes"
        />
      </div>

      {/* Error message */}
      {errors.submit && (
        <div className="p-3 bg-red-50 border border-red-200 rounded-lg">
          <p className="text-sm text-red-600">{errors.submit}</p>
        </div>
      )}

      {/* Actions */}
      <div className="flex gap-3">
        <button
          type="submit"
          disabled={isSubmitting}
          className="flex-1 bg-blue-500 hover:bg-blue-600 disabled:bg-blue-300 text-white px-4 py-2 rounded-lg transition-colors"
        >
          {isSubmitting ? 'Saving...' : mode === 'create' ? 'Create Task' : 'Save Changes'}
        </button>
        <button
          type="button"
          onClick={() => router.back()}
          className="px-4 py-2 bg-gray-200 hover:bg-gray-300 text-gray-700 rounded-lg transition-colors"
        >
          Cancel
        </button>
      </div>
    </form>
  )
}