package api

import (
	"encoding/json"
	"fmt"
	"io"
	"regexp"
)

func (s *Session) GetInvoice(identifier string) (map[string]interface{}, error) {
	var endpoint string

	isInvoiceNumber, _ := regexp.MatchString(`^[A-Za-z]`, identifier)

	if isInvoiceNumber {
		endpoint = fmt.Sprintf("/invoice?invoiceNumber=%s", identifier)
	} else {
		endpoint = fmt.Sprintf("/invoice/%s", identifier)
	}

	resp, err := s.DoRequest("GET", endpoint, nil)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	body, _ := io.ReadAll(resp.Body)
	if resp.StatusCode != 200 {
		return nil, fmt.Errorf("failed to get invoice info: %s, response: %s", resp.Status, string(body))
	}

	var result map[string]interface{}
	if err := json.Unmarshal(body, &result); err != nil {
		return nil, fmt.Errorf("error unmarshalling response: %v", err)
	}

	if data, ok := result["data"].(map[string]interface{}); ok {
		if invoices, ok := data["invoices"].([]interface{}); ok && len(invoices) > 0 {
			if invoice, ok := invoices[0].(map[string]interface{}); ok {
				return invoice, nil
			}
		} else {
			return data, nil
		}
	}

	return nil, fmt.Errorf("no invoice found in the response")
}