package reporter

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"time"
)

type Reporter struct {
	serverURL string
	token     string
	client    *http.Client
}

func NewReporter(serverURL, token string) *Reporter {
	return &Reporter{
		serverURL: serverURL,
		token:     token,
		client: &http.Client{
			Timeout: 10 * time.Second,
		},
	}
}

type RegisterRequest struct {
	Hostname string `json:"hostname"`
	OS       string `json:"os"`
	IP       string `json:"ip"`
}

type RegisterResponse struct {
	Device struct {
		ID    string `json:"id"`
		Token string `json:"token"`
	} `json:"device"`
}

func (r *Reporter) Register(hostname, osName, ip string) (string, error) {
	req := RegisterRequest{
		Hostname: hostname,
		OS:       osName,
		IP:       ip,
	}

	body, err := json.Marshal(req)
	if err != nil {
		return "", err
	}

	resp, err := r.client.Post(r.serverURL+"/api/v1/register", "application/json", bytes.NewBuffer(body))
	if err != nil {
		return "", fmt.Errorf("failed to register: %v", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		respBody, _ := io.ReadAll(resp.Body)
		return "", fmt.Errorf("registration failed: %s", string(respBody))
	}

	var regResp RegisterResponse
	if err := json.NewDecoder(resp.Body).Decode(&regResp); err != nil {
		return "", err
	}

	return regResp.Device.ID, nil
}

func (r *Reporter) Report(metrics interface{}) error {
	body, err := json.Marshal(metrics)
	if err != nil {
		return err
	}

	req, err := http.NewRequest("POST", r.serverURL+"/api/v1/report", bytes.NewBuffer(body))
	if err != nil {
		return err
	}

	req.Header.Set("Content-Type", "application/json")
	if r.token != "" {
		req.Header.Set("Authorization", "Bearer "+r.token)
	}

	resp, err := r.client.Do(req)
	if err != nil {
		return fmt.Errorf("failed to report: %v", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		respBody, _ := io.ReadAll(resp.Body)
		return fmt.Errorf("report failed: %s", string(respBody))
	}

	return nil
}

func (r *Reporter) Heartbeat(deviceID string) error {
	req, err := http.NewRequest("POST", r.serverURL+"/api/v1/devices/"+deviceID+"/heartbeat", nil)
	if err != nil {
		return err
	}

	if r.token != "" {
		req.Header.Set("Authorization", "Bearer "+r.token)
	}

	resp, err := r.client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	return nil
}