package main

import (
	"encoding/json"
	"fmt"
	"os"
	"path/filepath"
	"time"
)

const defaultUpdateStatusPath = "/var/lib/proxmox-dashboard/update-status.json"
const defaultUpdateRequestPath = "/var/lib/proxmox-dashboard/update-request"

type UpdateStatus struct {
	CurrentVersion   string    `json:"currentVersion"`
	AvailableVersion string    `json:"availableVersion"`
	State            string    `json:"state"`
	Mode             string    `json:"mode"`
	Message          string    `json:"message"`
	ReleaseURL       string    `json:"releaseUrl"`
	CheckedAt        time.Time `json:"checkedAt"`
}

func readUpdateStatus() UpdateStatus {
	status := UpdateStatus{CurrentVersion: version, State: "unknown", Mode: "notify"}
	path := os.Getenv("DASHBOARD_UPDATE_STATUS_PATH")
	if path == "" {
		path = defaultUpdateStatusPath
	}
	data, err := os.ReadFile(path)
	if err != nil || json.Unmarshal(data, &status) != nil {
		return status
	}
	status.CurrentVersion = version
	return status
}

func requestUpdate() (UpdateStatus, error) {
	requestPath := os.Getenv("DASHBOARD_UPDATE_REQUEST_PATH")
	if requestPath == "" {
		requestPath = defaultUpdateRequestPath
	}
	if err := os.MkdirAll(filepath.Dir(requestPath), 0o750); err != nil {
		return UpdateStatus{}, err
	}
	status := readUpdateStatus()
	status.State = "queued"
	status.Message = "Обновление поставлено в очередь."
	status.CheckedAt = time.Now()
	statusPath := os.Getenv("DASHBOARD_UPDATE_STATUS_PATH")
	if statusPath == "" {
		statusPath = defaultUpdateStatusPath
	}
	data, _ := json.Marshal(status)
	temporary, err := os.CreateTemp(filepath.Dir(statusPath), ".update-status-")
	if err != nil {
		return UpdateStatus{}, err
	}
	temporaryPath := temporary.Name()
	defer os.Remove(temporaryPath)
	if _, err = temporary.Write(data); err == nil {
		err = temporary.Chmod(0o644)
	}
	if closeErr := temporary.Close(); err == nil {
		err = closeErr
	}
	if err == nil {
		err = os.Rename(temporaryPath, statusPath)
	}
	if err != nil {
		return UpdateStatus{}, fmt.Errorf("не удалось сохранить запрос обновления: %w", err)
	}
	if err := os.WriteFile(requestPath, []byte(time.Now().Format(time.RFC3339Nano)), 0o640); err != nil {
		return UpdateStatus{}, err
	}
	return status, nil
}