package notifyha

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

type Notification struct {
	Event     string    `json:"event"`
	Severity  string    `json:"severity"`
	Title     string    `json:"title"`
	Message   string    `json:"message"`
	Source    string    `json:"source"`
	Tags      []string  `json:"tags,omitempty"`
	Timestamp time.Time `json:"timestamp"`
}

type Client struct {
	WebhookURL string
	HTTPClient *http.Client
}

func New(webhookURL string) *Client {
	return &Client{
		WebhookURL: webhookURL,
		HTTPClient: &http.Client{
			Timeout: 10 * time.Second,
		},
	}
}

func (c *Client) Send(n Notification) error {
	n.Timestamp = time.Now().UTC()
	body, err := json.Marshal(n)
	if err != nil {
		return err
	}

	resp, err := c.HTTPClient.Post(
		c.WebhookURL,
		"application/json",
		bytes.NewBuffer(body),
	)
	if err != nil {
		return err
	}

	defer resp.Body.Close()

	if resp.StatusCode >= 300 {
		return fmt.Errorf("webhook returned %s", resp.Status)
	}

	return nil
}

func (c *Client) Info(title, message, source string) error {
	return c.Send(Notification{
		Event:    "notification",
		Severity: Info,
		Title:    title,
		Message:  message,
		Source:   source,
	})
}

func (c *Client) Warning(title, message, source string) error {
	return c.Send(Notification{
		Event:    "notification",
		Severity: Warning,
		Title:    title,
		Message:  message,
		Source:   source,
	})
}

func (c *Client) Error(title, message, source string) error {
	return c.Send(Notification{
		Event:    "notification",
		Severity: Error,
		Title:    title,
		Message:  message,
		Source:   source,
	})
}

func (c *Client) Critical(title, message, source string) error {
	return c.Send(Notification{
		Event:    "notification",
		Severity: Critical,
		Title:    title,
		Message:  message,
		Source:   source,
	})
}