import type { PluginInput } from "@opencode-ai/plugin"
import { runBunInstall } from "../../../cli/config-manager"
import { log } from "../../../shared/logger"
import { invalidatePackage } from "../cache"
import { PACKAGE_NAME } from "../constants"
import { extractChannel } from "../version-channel"
import { findPluginEntry, getCachedVersion, getLatestVersion, revertPinnedVersion, syncCachePackageJsonToIntent } from "../checker"
import { showAutoUpdatedToast, showUpdateAvailableToast } from "./update-toasts"

function getPinnedVersionToastMessage(latestVersion: string): string {
  return `Update available: ${latestVersion} (version pinned, update manually)`
}

async function runBunInstallSafe(): Promise<boolean> {
  try {
    return await runBunInstall()
  } catch (err) {
    const errorMessage = err instanceof Error ? err.message : String(err)
    log("[auto-update-checker] bun install error:", errorMessage)
    return false
  }
}

export async function runBackgroundUpdateCheck(
  ctx: PluginInput,
  autoUpdate: boolean,
  getToastMessage: (isUpdate: boolean, latestVersion?: string) => string
): Promise<void> {
  const pluginInfo = findPluginEntry(ctx.directory)
  if (!pluginInfo) {
    log("[auto-update-checker] Plugin not found in config")
    return
  }

  const cachedVersion = getCachedVersion()
  const currentVersion = cachedVersion ?? pluginInfo.pinnedVersion
  if (!currentVersion) {
    log("[auto-update-checker] No version found (cached or pinned)")
    return
  }

  const channel = extractChannel(pluginInfo.pinnedVersion ?? currentVersion)
  const latestVersion = await getLatestVersion(channel)
  if (!latestVersion) {
    log("[auto-update-checker] Failed to fetch latest version for channel:", channel)
    return
  }

  if (currentVersion === latestVersion) {
    log("[auto-update-checker] Already on latest version for channel:", channel)
    return
  }

  log(`[auto-update-checker] Update available (${channel}): ${currentVersion} → ${latestVersion}`)

  if (!autoUpdate) {
    await showUpdateAvailableToast(ctx, latestVersion, getToastMessage)
    log("[auto-update-checker] Auto-update disabled, notification only")
    return
  }

  if (pluginInfo.isPinned) {
    await showUpdateAvailableToast(ctx, latestVersion, () => getPinnedVersionToastMessage(latestVersion))
    log(`[auto-update-checker] User-pinned version detected (${pluginInfo.entry}), skipping auto-update. Notification only.`)
    return
  }

  // Sync cache package.json to match opencode.json intent before updating
  // This handles the case where user switched from pinned version to tag (e.g., 3.10.0 -> @latest)
  syncCachePackageJsonToIntent(pluginInfo)

  invalidatePackage(PACKAGE_NAME)

  const installSuccess = await runBunInstallSafe()

  if (installSuccess) {
    await showAutoUpdatedToast(ctx, currentVersion, latestVersion)
    log(`[auto-update-checker] Update installed: ${currentVersion} → ${latestVersion}`)
    return
  }

  if (pluginInfo.isPinned) {
    revertPinnedVersion(pluginInfo.configPath, latestVersion, pluginInfo.entry)
    log("[auto-update-checker] Config reverted due to install failure")
  }

  await showUpdateAvailableToast(ctx, latestVersion, getToastMessage)
  log("[auto-update-checker] bun install failed; update not installed (falling back to notification-only)")
}