package schema

import (
	"errors"
	"reflect"

	"github.com/google/generative-ai-go/genai"
	"github.com/openai/openai-go"
)

const (
	// SyntheticFieldPrefix is any prefix that is added to any synthetic fields that are added to the object, to prevent
	// collisions with the fields in the struct.
	SyntheticFieldPrefix = "__"
)

type Object struct {
	basic

	ref reflect.Type

	fields map[string]Type

	// syntheticFields are fields that are not in the struct but are generated by a system.
	synetheticFields map[string]Type
}

func (o Object) WithSyntheticField(name string, description string) Object {
	if o.synetheticFields == nil {
		o.synetheticFields = map[string]Type{}
	}

	o.synetheticFields[name] = basic{
		DataType:    TypeString,
		typeName:    "string",
		index:       -1,
		required:    false,
		description: description,
	}

	return o
}

func (o Object) SyntheticFields() map[string]Type {
	return o.synetheticFields
}

func (o Object) OpenAIParameters() openai.FunctionParameters {
	var properties = map[string]openai.FunctionParameters{}
	var required []string
	for k, v := range o.fields {
		properties[k] = v.OpenAIParameters()
		if v.Required() {
			required = append(required, k)
		}
	}

	for k, v := range o.synetheticFields {
		properties[SyntheticFieldPrefix+k] = v.OpenAIParameters()
		if v.Required() {
			required = append(required, SyntheticFieldPrefix+k)
		}
	}

	var res = openai.FunctionParameters{
		"type":        "object",
		"description": o.Description(),
		"properties":  properties,
	}

	if len(required) > 0 {
		res["required"] = required
	}

	return res
}

func (o Object) GoogleParameters() *genai.Schema {
	var properties = map[string]*genai.Schema{}
	var required []string
	for k, v := range o.fields {
		properties[k] = v.GoogleParameters()
		if v.Required() {
			required = append(required, k)
		}
	}

	var res = &genai.Schema{
		Type:        genai.TypeObject,
		Description: o.Description(),
		Properties:  properties,
	}

	if len(required) > 0 {
		res.Required = required
	}

	return res
}

func (o Object) AnthropicInputSchema() map[string]any {
	var properties = map[string]any{}
	var required []string
	for k, v := range o.fields {
		properties[k] = v.AnthropicInputSchema()
		if v.Required() {
			required = append(required, k)
		}
	}

	var res = map[string]any{
		"type":        "object",
		"description": o.Description(),
		"properties":  properties,
	}

	if len(required) > 0 {
		res["required"] = required
	}

	return res
}

// FromAny converts the value from any to the correct type, returning the value, and an error if any
func (o Object) FromAny(val any) (reflect.Value, error) {
	// if the value is nil, we can't do anything
	if val == nil {
		return reflect.Value{}, nil
	}

	// now make a new object of the type we're trying to parse
	obj := reflect.New(o.ref).Elem()

	// now we need to iterate over the fields and set the values
	for k, v := range o.fields {
		// get the field by name
		field := obj.FieldByName(k)
		if !field.IsValid() {
			return reflect.Value{}, errors.New("field " + k + " not found")
		}

		// get the value from the map
		val2, ok := val.(map[string]interface{})[k]
		if !ok {
			return reflect.Value{}, errors.New("field " + k + " not found in map")
		}

		// now we need to convert the value to the correct type
		val3, err := v.FromAny(val2)
		if err != nil {
			return reflect.Value{}, err
		}

		// now we need to set the value on the field
		v.SetValueOnField(field, val3)

	}

	return obj, nil
}

func (o Object) SetValueOnField(obj reflect.Value, val reflect.Value) {
	// if this basic type is not required that means it's a pointer type so we need to set the value to the address of the value
	if !o.required {
		val = val.Addr()
	}

	obj.Field(o.index).Set(val)
}