package sender

import (
	"bytes"
	"context"
	"encoding/json"
	"errors"
	"io"
	"log"
	"net/http"
	"time"

	"rocketgit.ru/rsmon/worker/app/models"
	"rocketgit.ru/rsmon/worker/internal/wire"
)

// messageKindUp is the canonical string the notifier uses for "monitor
// just came back up" events. Lives here as a package-level constant so
// the goconst linter stops flagging the literal "up" appearing three
// times across the sender package.
const messageKindUp = "up"

// MattermostPayload provides functionality.
type MattermostPayload struct {
	Channel  *string `json:"channel,omitempty"`
	Username *string `json:"username,omitempty"`
	IconURL  *string `json:"icon_url,omitempty"`
	Text     *string `json:"text,omitempty"`
}

// RunMattermost provides functionality.
func RunMattermost(message *models.Message) (*string, error) {
	_, _, markdownBody, _ := GetContent(message, time.Now())

	s := "@channel "
	if message.Kind == messageKindUp {
		s += ":white_check_mark: "
	} else {
		s += ":warning: "
	}
	s = s + "\n\n" + markdownBody.String()

	color := "green"
	if message.Kind == "down" {
		color = "red"
	}

	un := "RSMon"
	icon := "https://rsmon.ru/" + color + "_logo.svg"
	payload := MattermostPayload{
		Text:     &s,
		Username: &un,
		IconURL:  &icon,
	}

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

	log.Println("send mattermost:", message.Contact.Value)
	// log.Println(string(body))

	resp, err := httpClient.Post(
		message.Contact.Value,
		"application/json",
		bytes.NewBuffer(body),
	)
	if err != nil {
		return nil, err
	}

	defer resp.Body.Close() //nolint:errcheck
	body, err = io.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}

	str := string(body)
	return &str, nil
}

// SendMattermostWithCredential delivers a Mattermost notification using the
// supplied wire credential block (which carries the default username +
// icon URL). The webhook URL is per-task; the credential block only sets
// the cosmetic defaults. This mirrors what the legacy RunMattermost did with
// secrets + a hardcoded RSMon username / icon.
func SendMattermostWithCredential(
	contactValue, messageKind, subject, markdownBody string,
	cred *wire.MattermostCredential,
) (*string, error) {
	return SendMattermostWithCredentialContext(context.Background(), contactValue, messageKind, subject, markdownBody, cred)
}

func SendMattermostWithCredentialContext(
	ctx context.Context, contactValue, messageKind, subject, markdownBody string,
	cred *wire.MattermostCredential,
) (*string, error) {
	if contactValue == "" {
		return nil, errors.New("mattermost contact value is empty")
	}

	s := "@channel "
	if messageKind == messageKindUp {
		s += ":white_check_mark: "
	} else {
		s += ":warning: "
	}
	s = s + "\n\n" + subject + "\n\n" + markdownBody

	color := "green"
	if messageKind == "down" {
		color = "red"
	}

	username := "RSMon"
	iconURL := "https://rsmon.ru/" + color + "_logo.svg"
	if cred != nil {
		if cred.DefaultUsername != "" {
			username = cred.DefaultUsername
		}
		if cred.DefaultIconURL != "" {
			iconURL = cred.DefaultIconURL
		}
	}

	payload := MattermostPayload{
		Text:     &s,
		Username: &username,
		IconURL:  &iconURL,
	}
	body, err := json.Marshal(payload)
	if err != nil {
		return nil, err
	}

	client := &http.Client{Timeout: 60 * time.Second}
	req, err := http.NewRequestWithContext(ctx, http.MethodPost, contactValue, bytes.NewBuffer(body))
	if err != nil {
		return nil, err
	}
	req.Header.Set("Content-Type", "application/json")
	resp, err := client.Do(req)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close() //nolint:errcheck

	respBody, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}
	str := string(respBody)
	return &str, nil
}