package wire

import (
	"encoding/json"
	"fmt"

	decimal "github.com/alpacahq/alpacadecimal"
)

// Unwrap returns the inner JSON of an optional {"data": ...} envelope.
func Unwrap(raw json.RawMessage) json.RawMessage {
	if len(raw) == 0 {
		return raw
	}
	var wrap struct {
		Data json.RawMessage `json:"data"`
	}
	if json.Unmarshal(raw, &wrap) == nil && len(wrap.Data) > 0 {
		return wrap.Data
	}
	return raw
}

// Dec parses a required money/size/price value.
func Dec(v any) (decimal.Decimal, error) {
	switch x := v.(type) {
	case nil:
		return decimal.Zero, nil
	case float64:
		return decimal.NewFromFloat(x), nil
	case json.Number:
		d, err := decimal.NewFromString(string(x))
		if err != nil {
			return decimal.Zero, fmt.Errorf("parse decimal: %v", v)
		}
		return d, nil
	case string:
		if x == "" {
			return decimal.Zero, nil
		}
		d, err := decimal.NewFromString(x)
		if err != nil {
			return decimal.Zero, fmt.Errorf("parse decimal: %v", v)
		}
		return d, nil
	default:
		return decimal.Zero, fmt.Errorf("parse decimal: %v", v)
	}
}

// DecOpt parses an optional money/size/price value.
func DecOpt(v any) (*decimal.Decimal, error) {
	if v == nil {
		return nil, nil
	}
	if s, ok := v.(string); ok && s == "" {
		return nil, nil
	}
	d, err := Dec(v)
	if err != nil {
		return nil, err
	}
	return &d, nil
}

// Encode is Decimal.String for Robinhood string wire fields.
func Encode(d decimal.Decimal) string {
	return d.String()
}