feat: Refactor CLI API client by splitting billing, carrier, and charging modules into separate files

- Extract Invoice, Payment, Subscriber types and GetInvoices, GetPayments, GenerateInvoice methods to billing.go
- Extract CarrierInfo, ConnectivityStatus, ProfileInfo types and carrier connector methods to carrier.go
- Extract CreditCheckRequest/Response, CreditBalanceResponse types and charging engine methods to charging.go
- Add PacketStats, CreditInfo types and GetPacketStats, GetCreditInfo

apps/cli/internal/api/billing.go

@@ -0,0 +1,155 @@
+package api
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"time"
+)
+
+// Invoice represents an invoice from the API
+type Invoice struct {
+	ID           string     `json:"id"`
+	SubscriberID string     `json:"subscriber_id"`
+	Amount       float64    `json:"amount"`
+	Status       string     `json:"status"`
+	CreatedAt    time.Time  `json:"created_at"`
+	DueDate      time.Time  `json:"due_date"`
+	PaidAt       *time.Time `json:"paid_at,omitempty"`
+	Subscriber   Subscriber `json:"subscriber"`
+}
+
+// Payment represents a payment from the API
+type Payment struct {
+	ID          string     `json:"id"`
+	InvoiceID   string     `json:"invoice_id"`
+	Amount      float64    `json:"amount"`
+	Method      string     `json:"method"`
+	Status      string     `json:"status"`
+	CreatedAt   time.Time  `json:"created_at"`
+	ProcessedAt *time.Time `json:"processed_at,omitempty"`
+}
+
+// GenerateInvoiceRequest represents a request to generate an invoice
+type GenerateInvoiceRequest struct {
+	SubscriberID string `json:"subscriber_id"`
+}
+
+// GenerateInvoiceResponse represents a response from generating an invoice
+type GenerateInvoiceResponse struct {
+	ID        string    `json:"id"`
+	Amount    float64   `json:"amount"`
+	Status    string    `json:"status"`
+	CreatedAt time.Time `json:"created_at"`
+	DueDate   time.Time `json:"due_date"`
+}
+
+// GetInvoices retrieves invoices from the API
+func (c *Client) GetInvoices() ([]Invoice, error) {
+	url := fmt.Sprintf("%s/api/v1/invoices", c.baseURL)
+
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create request: %w", err)
+	}
+
+	req.Header.Set("Authorization", "Bearer "+c.apiKey)
+	req.Header.Set("Content-Type", "application/json")
+
+	resp, err := c.httpClient.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("failed to make request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		body, _ := io.ReadAll(resp.Body)
+		return nil, fmt.Errorf("API request failed with status %d: %s", resp.StatusCode, string(body))
+	}
+
+	var response struct {
+		Data []Invoice `json:"data"`
+	}
+
+	if err := json.NewDecoder(resp.Body).Decode(&response); err != nil {
+		return nil, fmt.Errorf("failed to decode response: %w", err)
+	}
+
+	return response.Data, nil
+}
+
+// GetPayments retrieves payments from the API
+func (c *Client) GetPayments() ([]Payment, error) {
+	url := fmt.Sprintf("%s/api/v1/payments", c.baseURL)
+
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create request: %w", err)
+	}
+
+	req.Header.Set("Authorization", "Bearer "+c.apiKey)
+	req.Header.Set("Content-Type", "application/json")
+
+	resp, err := c.httpClient.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("failed to make request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		body, _ := io.ReadAll(resp.Body)
+		return nil, fmt.Errorf("API request failed with status %d: %s", resp.StatusCode, string(body))
+	}
+
+	var response struct {
+		Data []Payment `json:"data"`
+	}
+
+	if err := json.NewDecoder(resp.Body).Decode(&response); err != nil {
+		return nil, fmt.Errorf("failed to decode response: %w", err)
+	}
+
+	return response.Data, nil
+}
+
+// GenerateInvoice generates a new invoice for a subscriber
+func (c *Client) GenerateInvoice(subscriberID string) (*GenerateInvoiceResponse, error) {
+	url := fmt.Sprintf("%s/api/v1/invoices/generate", c.baseURL)
+
+	request := GenerateInvoiceRequest{
+		SubscriberID: subscriberID,
+	}
+
+	jsonData, err := json.Marshal(request)
+	if err != nil {
+		return nil, fmt.Errorf("failed to marshal request: %w", err)
+	}
+
+	req, err := http.NewRequest("POST", url, bytes.NewBuffer(jsonData))
+	if err != nil {
+		return nil, fmt.Errorf("failed to create request: %w", err)
+	}
+
+	req.Header.Set("Authorization", "Bearer "+c.apiKey)
+	req.Header.Set("Content-Type", "application/json")
+
+	resp, err := c.httpClient.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("failed to make request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusCreated {
+		body, _ := io.ReadAll(resp.Body)
+		return nil, fmt.Errorf("API request failed with status %d: %s", resp.StatusCode, string(body))
+	}
+
+	var response GenerateInvoiceResponse
+	if err := json.NewDecoder(resp.Body).Decode(&response); err != nil {
+		return nil, fmt.Errorf("failed to decode response: %w", err)
+	}
+
+	return &response, nil
+}