package nacosx

import (
	"encoding/json"
	"fmt"
	"io"
	"log"
	"net/http"
	"net/url"
	"strconv"
	"strings"
	"time"
)

type Config struct {
	Server      string
	NamespaceID string
	BindIP      string
	Timeout     time.Duration
}

type Client struct {
	baseURL     string
	namespaceID string
	bindIP      string
	client      *http.Client
}

func New(cfg Config) *Client {
	timeout := cfg.Timeout
	if timeout == 0 {
		timeout = 15 * time.Second
	}
	return &Client{
		baseURL:     strings.TrimRight(cfg.Server, "/"),
		namespaceID: cfg.NamespaceID,
		bindIP:      cfg.BindIP,
		client:      &http.Client{Timeout: timeout},
	}
}

func (c *Client) BaseURL() string {
	return c.baseURL
}

func (c *Client) BindIP() string {
	return c.bindIP
}

func (c *Client) ConfigJSON(dataID string, dst any) error {
	body, err := c.GetConfig(dataID)
	if err != nil {
		return err
	}
	return json.Unmarshal(body, dst)
}

func (c *Client) GetConfig(dataID string) ([]byte, error) {
	u, _ := url.Parse(c.baseURL + "/nacos/v1/cs/configs")
	q := u.Query()
	q.Set("dataId", dataID)
	q.Set("group", "DEFAULT_GROUP")
	q.Set("tenant", c.namespaceID)
	u.RawQuery = q.Encode()

	resp, err := c.client.Get(u.String())
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()
	body, _ := io.ReadAll(resp.Body)
	if resp.StatusCode >= http.StatusMultipleChoices {
		return nil, fmt.Errorf("nacos config %s status=%d body=%s", dataID, resp.StatusCode, string(body))
	}
	return body, nil
}

func (c *Client) Register(serviceName string, port int) error {
	values := url.Values{}
	values.Set("serviceName", serviceName)
	values.Set("ip", c.bindIP)
	values.Set("port", strconv.Itoa(port))
	values.Set("namespaceId", c.namespaceID)
	values.Set("ephemeral", "true")
	resp, err := c.client.PostForm(c.baseURL+"/nacos/v1/ns/instance", values)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode >= http.StatusMultipleChoices {
		body, _ := io.ReadAll(resp.Body)
		return fmt.Errorf("status=%d body=%s", resp.StatusCode, string(body))
	}
	return nil
}

func (c *Client) Heartbeat(serviceName string, port int) {
	ticker := time.NewTicker(5 * time.Second)
	defer ticker.Stop()
	for range ticker.C {
		beat, _ := json.Marshal(map[string]any{"serviceName": serviceName, "ip": c.bindIP, "port": port, "ephemeral": true})
		u, _ := url.Parse(c.baseURL + "/nacos/v1/ns/instance/beat")
		q := u.Query()
		q.Set("serviceName", serviceName)
		q.Set("ip", c.bindIP)
		q.Set("port", strconv.Itoa(port))
		q.Set("namespaceId", c.namespaceID)
		q.Set("beat", string(beat))
		u.RawQuery = q.Encode()
		req, _ := http.NewRequest(http.MethodPut, u.String(), nil)
		resp, err := c.client.Do(req)
		if err != nil {
			log.Printf("nacos heartbeat failed: %v", err)
			continue
		}
		io.Copy(io.Discard, resp.Body)
		resp.Body.Close()
		if resp.StatusCode >= http.StatusMultipleChoices {
			log.Printf("nacos heartbeat status=%d", resp.StatusCode)
		}
	}
}