'use client';

import { useState } from 'react';
import { Plus, Minus, ChevronDown, ChevronRight } from 'lucide-react';
import { Button } from './ui/button';
import { Input } from './ui/input';
import { Card } from './ui/card';

export interface SchemaField {
  id: string;
  name: string;
  type: 'field' | 'group';
  description: string;
  fields?: SchemaField[];
}

const defaultSchema: SchemaField[] = [
  {
    id: '1',
    name: 'company',
    type: 'field',
    description: 'name of company'
  },
  {
    id: '2',
    name: 'address',
    type: 'field',
    description: 'address of company'
  },
  {
    id: '3',
    name: 'total_sum',
    type: 'field',
    description: 'total amount we purchased'
  },
  {
    id: '4',
    name: 'items',
    type: 'group',
    description: 'list of items purchased',
    fields: [
      {
        id: '4.1',
        name: 'item',
        type: 'field',
        description: 'name of item'
      },
      {
        id: '4.2',
        name: 'unit_price',
        type: 'field',
        description: 'unit price of item'
      },
      {
        id: '4.3',
        name: 'quantity',
        type: 'field',
        description: 'quantity we purchased'
      },
      {
        id: '4.4',
        name: 'sum',
        type: 'field',
        description: 'total amount we purchased'
      }
    ]
  }
];

interface SchemaDefinitionProps {
  onSchemaChange: (schema: SchemaField[]) => void;
}

export function SchemaDefinition({ onSchemaChange }: SchemaDefinitionProps) {
  const [schema, setSchema] = useState<SchemaField[]>(defaultSchema);
  const [expandedGroups, setExpandedGroups] = useState<Set<string>>(new Set(['4']));

  const toggleGroup = (id: string) => {
    setExpandedGroups(prev => {
      const next = new Set(prev);
      if (next.has(id)) {
        next.delete(id);
      } else {
        next.add(id);
      }
      return next;
    });
  };

  const addField = (parentId?: string) => {
    const newField: SchemaField = {
      id: Date.now().toString(),
      name: '',
      type: 'field',
      description: ''
    };

    if (parentId) {
      setSchema(prev => {
        const updateFields = (fields: SchemaField[]): SchemaField[] => {
          return fields.map(field => {
            if (field.id === parentId) {
              return {
                ...field,
                fields: [...(field.fields || []), newField]
              };
            }
            if (field.fields) {
              return {
                ...field,
                fields: updateFields(field.fields)
              };
            }
            return field;
          });
        };
        return updateFields(prev);
      });
    } else {
      setSchema(prev => [...prev, newField]);
    }
  };

  const addGroup = (parentId?: string) => {
    const newGroup: SchemaField = {
      id: Date.now().toString(),
      name: '',
      type: 'group',
      description: '',
      fields: []
    };

    if (parentId) {
      setSchema(prev => {
        const updateFields = (fields: SchemaField[]): SchemaField[] => {
          return fields.map(field => {
            if (field.id === parentId) {
              return {
                ...field,
                fields: [...(field.fields || []), newGroup]
              };
            }
            if (field.fields) {
              return {
                ...field,
                fields: updateFields(field.fields)
              };
            }
            return field;
          });
        };
        return updateFields(prev);
      });
    } else {
      setSchema(prev => [...prev, newGroup]);
    }
    setExpandedGroups(prev => new Set([...prev, newGroup.id]));
  };

  const removeField = (id: string) => {
    const removeFieldFromArray = (fields: SchemaField[]): SchemaField[] => {
      return fields.filter(field => {
        if (field.id === id) return false;
        if (field.fields) {
          field.fields = removeFieldFromArray(field.fields);
        }
        return true;
      });
    };

    setSchema(prev => removeFieldFromArray(prev));
  };

  const updateField = (id: string, updates: Partial<SchemaField>) => {
    const updateFieldInArray = (fields: SchemaField[]): SchemaField[] => {
      return fields.map(field => {
        if (field.id === id) {
          return { ...field, ...updates };
        }
        if (field.fields) {
          return {
            ...field,
            fields: updateFieldInArray(field.fields)
          };
        }
        return field;
      });
    };

    const updatedSchema = updateFieldInArray(schema);
    setSchema(updatedSchema);
    onSchemaChange(updatedSchema);
  };

  const renderField = (field: SchemaField, depth = 0) => {
    const isExpanded = expandedGroups.has(field.id);

    return (
      <div key={field.id} className="space-y-2" style={{ marginLeft: `${depth * 20}px` }}>
        <Card className="p-4">
          <div className="flex items-center space-x-2">
            {field.type === 'group' && (
              <Button
                variant="ghost"
                size="icon"
                onClick={() => toggleGroup(field.id)}
              >
                {isExpanded ? (
                  <ChevronDown className="h-4 w-4" />
                ) : (
                  <ChevronRight className="h-4 w-4" />
                )}
              </Button>
            )}
            <Input
              placeholder="Field name"
              value={field.name}
              onChange={(e) => updateField(field.id, { name: e.target.value })}
              className="flex-1"
            />
            <Input
              placeholder="Description"
              value={field.description}
              onChange={(e) => updateField(field.id, { description: e.target.value })}
              className="flex-1"
            />
            <Button
              variant="destructive"
              size="icon"
              onClick={() => removeField(field.id)}
            >
              <Minus className="h-4 w-4" />
            </Button>
          </div>
        </Card>

        {field.type === 'group' && isExpanded && (
          <div className="space-y-2">
            {field.fields?.map(subField => renderField(subField, depth + 1))}
            <div className="flex space-x-2" style={{ marginLeft: `${(depth + 1) * 20}px` }}>
              <Button
                variant="outline"
                size="sm"
                onClick={() => addField(field.id)}
              >
                <Plus className="h-4 w-4 mr-2" />
                Add Field
              </Button>
              <Button
                variant="outline"
                size="sm"
                onClick={() => addGroup(field.id)}
              >
                <Plus className="h-4 w-4 mr-2" />
                Add Group
              </Button>
            </div>
          </div>
        )}
      </div>
    );
  };

  return (
    <div className="space-y-4">
      <div className="flex justify-between items-center">
        <h2 className="text-lg font-semibold">Schema Definition</h2>
        <div className="space-x-2">
          <Button variant="outline" onClick={() => addField()}>
            <Plus className="h-4 w-4 mr-2" />
            Add Field
          </Button>
          <Button variant="outline" onClick={() => addGroup()}>
            <Plus className="h-4 w-4 mr-2" />
            Add Group
          </Button>
        </div>
      </div>
      <div className="space-y-2">
        {schema.map(field => renderField(field))}
      </div>
    </div>
  );
}
