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, fmt.Errorf("error making request: %v", err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("error reading response body: %v", err)
	}

	if resp.StatusCode == 403 {
		// Handle 403 Forbidden specifically
		return nil, fmt.Errorf("access forbidden: you may not have permission to view this invoice")
	}

	if resp.StatusCode != 200 {
		return nil, fmt.Errorf("failed to get invoice info: %s", resp.Status)
	}

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

	// Log the entire response for debugging
	fmt.Printf("API Response: %+v\n", result)

	if isInvoiceNumber {
		// Handle invoice number case
		data, ok := result["data"].(map[string]interface{})
		if !ok {
			return nil, nil // No invoice found
		}
		invoices, ok := data["invoices"].([]interface{})
		if !ok || len(invoices) == 0 {
			return nil, nil // No invoice found
		}
		invoice, ok := invoices[0].(map[string]interface{})
		if !ok {
			return nil, fmt.Errorf("unexpected invoice structure")
		}
		return invoice, nil
	} else {
		// Handle invoice ID case
		data, ok := result["data"].(map[string]interface{})
		if !ok || len(data) == 0 {
			return nil, nil // No invoice found
		}
		return data, nil
	}
}