// Package jsonschema provides very simple functionality for representing a JSON schema as a
// (nested) struct. This struct can be used with the chat completion "function call" feature.
// For more complicated schemas, it is recommended to use a dedicated JSON schema library
// and/or pass in the schema in []byte format.
package jsonschema

import "encoding/json"

type DataType string

const (
	Object  DataType = "object"
	Number  DataType = "number"
	Integer DataType = "integer"
	String  DataType = "string"
	Array   DataType = "array"
	Null    DataType = "null"
	Boolean DataType = "boolean"
)

// Definition is a struct for describing a JSON Schema.
// It is fairly limited, and you may have better luck using a third-party library.
type Definition struct {
	// Type specifies the data type of the schema.
	Type DataType `json:"type,omitempty"`
	// Description is the description of the schema.
	Description string `json:"description,omitempty"`
	// Enum is used to restrict a value to a fixed set of values. It must be an array with at least
	// one element, where each element is unique. You will probably only use this with strings.
	Enum []string `json:"enum,omitempty"`
	// Properties describes the properties of an object, if the schema type is Object.
	Properties map[string]Definition `json:"properties"`
	// Required specifies which properties are required, if the schema type is Object.
	Required []string `json:"required,omitempty"`
	// Items specifies which data type an array contains, if the schema type is Array.
	Items *Definition `json:"items,omitempty"`
}

func (d *Definition) MarshalJSON() ([]byte, error) {
	d.initializeProperties()
	return json.Marshal(*d)
}

func (d *Definition) initializeProperties() {
	if d.Properties == nil {
		d.Properties = make(map[string]Definition)
		return
	}

	for k, v := range d.Properties {
		if v.Properties == nil {
			v.Properties = make(map[string]Definition)
		} else {
			v.initializeProperties()
		}
		d.Properties[k] = v
	}
}