import { nativeImage } from 'electron/common'
import type { BrowserWindow as ElectronBrowserWindow } from 'electron/main'
import { app } from 'electron/main'

import {
  APP_ICON_DANGER_BASE64,
  APP_ICON_NORMAL_BASE64,
  WINDOWS_OVERLAY_ICON_BASE64,
} from './brand-icons'
import { createRuntimeSnapshot } from './runtime-snapshot'
import { updateTrayIssueIndicator } from './tray'

type RuntimeSnapshot = ReturnType<typeof createRuntimeSnapshot>
type AppIconTone = 'normal' | 'danger'
type AppIndicatorImage = ReturnType<typeof nativeImage.createFromBuffer>

const HEALTH_ISSUE_AUTH_STATES = new Set(['expired', 'revoked', 'challenge_required'])
const ISSUE_INDICATOR_REFRESH_MS = 15_000

let refreshTimer: ReturnType<typeof setInterval> | null = null
const appIconCache = new Map<AppIconTone, AppIndicatorImage>()
let overlayIcon: AppIndicatorImage | null = null

function compactCount(count: number): string {
  return count > 99 ? '99+' : String(count)
}

function normalizeIssueCount(count: number): number {
  if (!Number.isFinite(count)) {
    return 0
  }
  return Math.max(0, Math.floor(count))
}

function iconFromBase64(base64: string): AppIndicatorImage {
  const icon = nativeImage.createFromBuffer(Buffer.from(base64, 'base64'))
  return icon.isEmpty() ? nativeImage.createEmpty() : icon
}

export function createDesktopHealthIcon(tone: AppIconTone): AppIndicatorImage {
  const cached = appIconCache.get(tone)
  if (cached) {
    return cached
  }

  const icon = iconFromBase64(tone === 'danger' ? APP_ICON_DANGER_BASE64 : APP_ICON_NORMAL_BASE64)
  appIconCache.set(tone, icon)
  return icon
}

function createWindowsOverlayIcon(): AppIndicatorImage {
  if (overlayIcon) {
    return overlayIcon
  }
  overlayIcon = iconFromBase64(WINDOWS_OVERLAY_ICON_BASE64)
  return overlayIcon
}

function healthIssueCount(snapshot: RuntimeSnapshot): number {
  return snapshot.accounts.filter((account) => HEALTH_ISSUE_AUTH_STATES.has(account.authState))
    .length
}

function applyPlatformAppIndicator(issueCount: number, window: ElectronBrowserWindow | null): void {
  const safeCount = normalizeIssueCount(issueCount)
  const hasIssues = safeCount > 0
  const icon = createDesktopHealthIcon(hasIssues ? 'danger' : 'normal')

  updateTrayIssueIndicator(safeCount)

  if (process.platform === 'darwin') {
    app.dock?.setIcon(icon)
    app.dock?.setBadge(hasIssues ? compactCount(safeCount) : '')
    app.setBadgeCount(safeCount)
    return
  }

  if (process.platform === 'linux') {
    app.setBadgeCount(safeCount)
  }

  if (!window || window.isDestroyed()) {
    return
  }

  window.setIcon(icon)

  if (process.platform === 'win32') {
    window.setOverlayIcon(
      hasIssues ? createWindowsOverlayIcon() : null,
      hasIssues ? `${safeCount} 个账号健康问题` : '',
    )
  }
}

export function applyDesktopHealthIndicatorFromSnapshot(
  snapshot: RuntimeSnapshot,
  window: ElectronBrowserWindow | null,
): void {
  applyPlatformAppIndicator(healthIssueCount(snapshot), window)
}

export function syncDesktopHealthIndicator(window: ElectronBrowserWindow | null): void {
  try {
    applyDesktopHealthIndicatorFromSnapshot(createRuntimeSnapshot(), window)
  } catch (error) {
    console.warn('[desktop-health-indicator] sync failed', {
      message: error instanceof Error ? error.message : String(error),
    })
  }
}

export function startDesktopHealthIndicator(getWindow: () => ElectronBrowserWindow | null): void {
  if (refreshTimer) {
    clearInterval(refreshTimer)
    refreshTimer = null
  }

  syncDesktopHealthIndicator(getWindow())
  refreshTimer = setInterval(() => {
    syncDesktopHealthIndicator(getWindow())
  }, ISSUE_INDICATOR_REFRESH_MS)
  refreshTimer.unref?.()
}