package builtin

import (
	"context"
	"encoding/json"
	"fmt"

	"modernc.org/quickjs"
)

func createWrapper[T Args, R any](fn Func[T, R], isAsync bool) interface{} {
	if !isAsync {
		return createSyncWrapper[T, R](fn)
	}
	return createAsyncWrapper[T, R](fn)
}

func createSyncWrapper[T Args, R any](fn Func[T, R]) interface{} {
	return func(rawArgs any) (R, error) {
		var zero R
		var args T

		obj, ok := rawArgs.(*quickjs.Object)
		if ok {
			jsonData, err := obj.MarshalJSON()
			if err != nil {
				return zero, fmt.Errorf("failed to marshal args: %w", err)
			}
			if err := json.Unmarshal(jsonData, &args); err != nil {
				return zero, fmt.Errorf("failed to unmarshal args: %w", err)
			}
		} else if rawArgs != nil && rawArgs != quickjs.UndefinedValue {
			jsonData, err := json.Marshal(rawArgs)
			if err != nil {
				return zero, fmt.Errorf("failed to marshal args: %w", err)
			}
			if err := json.Unmarshal(jsonData, &args); err != nil {
				return zero, fmt.Errorf("failed to unmarshal args: %w", err)
			}
		}

		if err := args.Validate(); err != nil {
			return zero, fmt.Errorf("argument validation failed: %w", err)
		}

		ctx := context.Background()
		return fn(ctx, args)
	}
}

func createAsyncWrapper[T Args, R any](fn Func[T, R]) interface{} {
	return func(rawArgs any) (any, error) {
		var args T

		obj, ok := rawArgs.(*quickjs.Object)
		if ok {
			jsonData, err := obj.MarshalJSON()
			if err != nil {
				return nil, fmt.Errorf("failed to marshal args: %w", err)
			}
			if err := json.Unmarshal(jsonData, &args); err != nil {
				return nil, fmt.Errorf("failed to unmarshal args: %w", err)
			}
		} else if rawArgs != nil && rawArgs != quickjs.UndefinedValue {
			jsonData, err := json.Marshal(rawArgs)
			if err != nil {
				return nil, fmt.Errorf("failed to marshal args: %w", err)
			}
			if err := json.Unmarshal(jsonData, &args); err != nil {
				return nil, fmt.Errorf("failed to unmarshal args: %w", err)
			}
		}

		if err := args.Validate(); err != nil {
			return nil, fmt.Errorf("argument validation failed: %w", err)
		}

		ctx := context.Background()
		return fn(ctx, args)
	}
}