'use client'

import { useState } from 'react'
import { Filter, X, ChevronDown, ChevronUp } from 'lucide-react'

export interface FilterState {
  priority: 'low' | 'medium' | 'high' | null
  completed: boolean | null
  tags: string[]
  dueDateRange: { start: Date | null; end: Date | null }
  sortBy: 'createdAt' | 'dueDate' | 'priority' | 'title'
  sortOrder: 'asc' | 'desc'
}

interface FilterPanelProps {
  filters: FilterState
  onFiltersChange: (filters: FilterState) => void
  availableTags?: string[]
  showListScope?: boolean
}

export default function FilterPanel({ 
  filters, 
  onFiltersChange,
  availableTags = [],
  showListScope = false
}: FilterPanelProps) {
  const [isExpanded, setIsExpanded] = useState(false)

  const hasActiveFilters = 
    filters.priority !== null || 
    filters.completed !== null || 
    filters.tags.length > 0 ||
    filters.dueDateRange.start !== null ||
    filters.dueDateRange.end !== null

  const handlePriorityChange = (priority: 'low' | 'medium' | 'high' | null) => {
    onFiltersChange({ ...filters, priority })
  }

  const handleCompletedChange = (completed: boolean | null) => {
    onFiltersChange({ ...filters, completed })
  }

  const handleTagToggle = (tag: string) => {
    const newTags = filters.tags.includes(tag)
      ? filters.tags.filter(t => t !== tag)
      : [...filters.tags, tag]
    onFiltersChange({ ...filters, tags: newTags })
  }

  const handleDueDateStartChange = (date: string) => {
    const start = date ? new Date(date) : null
    onFiltersChange({ 
      ...filters, 
      dueDateRange: { ...filters.dueDateRange, start } 
    })
  }

  const handleDueDateEndChange = (date: string) => {
    const end = date ? new Date(date) : null
    onFiltersChange({ 
      ...filters, 
      dueDateRange: { ...filters.dueDateRange, end } 
    })
  }

  const handleSortByChange = (sortBy: FilterState['sortBy']) => {
    onFiltersChange({ ...filters, sortBy })
  }

  const handleSortOrderToggle = () => {
    onFiltersChange({ 
      ...filters, 
      sortOrder: filters.sortOrder === 'asc' ? 'desc' : 'asc' 
    })
  }

  const handleClearFilters = () => {
    onFiltersChange({
      priority: null,
      completed: null,
      tags: [],
      dueDateRange: { start: null, end: null },
      sortBy: 'createdAt',
      sortOrder: 'desc'
    })
  }

  return (
    <div className="bg-white rounded-lg border border-gray-200 overflow-hidden">
      {/* Header */}
      <button
        onClick={() => setIsExpanded(!isExpanded)}
        className="w-full flex items-center justify-between p-4 hover:bg-gray-50 transition-colors"
      >
        <div className="flex items-center gap-2">
          <Filter size={20} className="text-gray-600" />
          <span className="font-medium text-gray-900">Filters & Sort</span>
          {hasActiveFilters && (
            <span className="bg-blue-100 text-blue-700 text-xs font-medium px-2 py-1 rounded">
              Active
            </span>
          )}
        </div>
        {isExpanded ? (
          <ChevronUp size={20} className="text-gray-400" />
        ) : (
          <ChevronDown size={20} className="text-gray-400" />
        )}
      </button>

      {/* Filter Controls */}
      {isExpanded && (
        <div className="p-4 border-t border-gray-200 space-y-4">
          {/* Sort Controls */}
          <div>
            <label className="block text-sm font-medium text-gray-700 mb-2">
              Sort By
            </label>
            <div className="flex gap-2">
              <select
                value={filters.sortBy}
                onChange={(e) => handleSortByChange(e.target.value as FilterState['sortBy'])}
                className="flex-1 px-3 py-2 border border-gray-300 rounded-lg focus:outline-none focus:ring-2 focus:ring-blue-500"
              >
                <option value="createdAt">Created Date</option>
                <option value="dueDate">Due Date</option>
                <option value="priority">Priority</option>
                <option value="title">Title</option>
              </select>
              <button
                onClick={handleSortOrderToggle}
                className="px-3 py-2 border border-gray-300 rounded-lg hover:bg-gray-50 transition-colors"
                title={filters.sortOrder === 'asc' ? 'Ascending' : 'Descending'}
              >
                {filters.sortOrder === 'asc' ? '↑' : '↓'}
              </button>
            </div>
          </div>

          {/* Priority Filter */}
          <div>
            <label className="block text-sm font-medium text-gray-700 mb-2">
              Priority
            </label>
            <div className="flex gap-2">
              <button
                onClick={() => handlePriorityChange(null)}
                className={`flex-1 px-3 py-2 rounded-lg border transition-colors ${
                  filters.priority === null
                    ? 'bg-blue-50 border-blue-500 text-blue-700'
                    : 'border-gray-300 hover:bg-gray-50'
                }`}
              >
                All
              </button>
              <button
                onClick={() => handlePriorityChange('low')}
                className={`flex-1 px-3 py-2 rounded-lg border transition-colors ${
                  filters.priority === 'low'
                    ? 'bg-green-50 border-green-500 text-green-700'
                    : 'border-gray-300 hover:bg-gray-50'
                }`}
              >
                Low
              </button>
              <button
                onClick={() => handlePriorityChange('medium')}
                className={`flex-1 px-3 py-2 rounded-lg border transition-colors ${
                  filters.priority === 'medium'
                    ? 'bg-yellow-50 border-yellow-500 text-yellow-700'
                    : 'border-gray-300 hover:bg-gray-50'
                }`}
              >
                Medium
              </button>
              <button
                onClick={() => handlePriorityChange('high')}
                className={`flex-1 px-3 py-2 rounded-lg border transition-colors ${
                  filters.priority === 'high'
                    ? 'bg-red-50 border-red-500 text-red-700'
                    : 'border-gray-300 hover:bg-gray-50'
                }`}
              >
                High
              </button>
            </div>
          </div>

          {/* Completion Status Filter */}
          <div>
            <label className="block text-sm font-medium text-gray-700 mb-2">
              Status
            </label>
            <div className="flex gap-2">
              <button
                onClick={() => handleCompletedChange(null)}
                className={`flex-1 px-3 py-2 rounded-lg border transition-colors ${
                  filters.completed === null
                    ? 'bg-blue-50 border-blue-500 text-blue-700'
                    : 'border-gray-300 hover:bg-gray-50'
                }`}
              >
                All
              </button>
              <button
                onClick={() => handleCompletedChange(false)}
                className={`flex-1 px-3 py-2 rounded-lg border transition-colors ${
                  filters.completed === false
                    ? 'bg-blue-50 border-blue-500 text-blue-700'
                    : 'border-gray-300 hover:bg-gray-50'
                }`}
              >
                Incomplete
              </button>
              <button
                onClick={() => handleCompletedChange(true)}
                className={`flex-1 px-3 py-2 rounded-lg border transition-colors ${
                  filters.completed === true
                    ? 'bg-blue-50 border-blue-500 text-blue-700'
                    : 'border-gray-300 hover:bg-gray-50'
                }`}
              >
                Completed
              </button>
            </div>
          </div>

          {/* Tags Filter */}
          {availableTags.length > 0 && (
            <div>
              <label className="block text-sm font-medium text-gray-700 mb-2">
                Tags
              </label>
              <div className="flex flex-wrap gap-2">
                {availableTags.map((tag) => (
                  <button
                    key={tag}
                    onClick={() => handleTagToggle(tag)}
                    className={`px-3 py-1 rounded-full text-sm border transition-colors ${
                      filters.tags.includes(tag)
                        ? 'bg-blue-50 border-blue-500 text-blue-700'
                        : 'border-gray-300 hover:bg-gray-50'
                    }`}
                  >
                    {tag}
                  </button>
                ))}
              </div>
            </div>
          )}

          {/* Due Date Range Filter */}
          <div>
            <label className="block text-sm font-medium text-gray-700 mb-2">
              Due Date Range
            </label>
            <div className="grid grid-cols-2 gap-2">
              <div>
                <label className="block text-xs text-gray-500 mb-1">From</label>
                <input
                  type="date"
                  value={filters.dueDateRange.start ? filters.dueDateRange.start.toISOString().split('T')[0] : ''}
                  onChange={(e) => handleDueDateStartChange(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>
              <div>
                <label className="block text-xs text-gray-500 mb-1">To</label>
                <input
                  type="date"
                  value={filters.dueDateRange.end ? filters.dueDateRange.end.toISOString().split('T')[0] : ''}
                  onChange={(e) => handleDueDateEndChange(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>
            </div>
          </div>

          {/* Clear Filters Button */}
          {hasActiveFilters && (
            <button
              onClick={handleClearFilters}
              className="w-full flex items-center justify-center gap-2 px-4 py-2 bg-gray-100 hover:bg-gray-200 text-gray-700 rounded-lg transition-colors"
            >
              <X size={16} />
              Clear All Filters
            </button>
          )}
        </div>
      )}
    </div>
  )
}