# Author: fruit.com.cn
#
# 服务看门狗：每 2 分钟检查一次，挂了自动拉起，连续失败发飞书告警。
# 注册为 Windows 计划任务后无人值守运行。

param(
    [string]$ComposeDir = "C:\FruitServer",
    [string]$LogDir = "C:\FruitServer\logs",
    [string]$FeishuWebhook = "",
    [int]$MaxRestarts = 3,
    [string]$FrontendTask = "FruitShorts-Web-3005"
)

$ErrorActionPreference = "Continue"
$ComposeFile = Join-Path $ComposeDir "docker-compose.yml"
$LogFile = Join-Path $LogDir "watchdog-$(Get-Date -Format 'yyyy-MM-dd').log"
# 连续失败计数落盘文件：计划任务每 2 分钟起一个新进程，计数只放进程内永远累积不到
# $MaxRestarts，告警会静默哑火。
$StateFile = Join-Path $LogDir "watchdog-state.json"

function Write-Log($msg) {
    $line = "$(Get-Date -Format 'yyyy-MM-dd HH:mm:ss') $msg"
    Add-Content -Path $LogFile -Value $line -ErrorAction SilentlyContinue
}

function Send-Alert($title, $msg) {
    if (-not $FeishuWebhook) { return }
    $body = @{
        msg_type = "text"
        content  = @{ text = "[$title] $msg" }
    } | ConvertTo-Json -Depth 3
    try {
        Invoke-RestMethod -Uri $FeishuWebhook -Method Post -Body $body -ContentType "application/json" -TimeoutSec 10
    } catch {
        Write-Log "飞书告警发送失败: $_"
    }
}

# 连续失败计数的读写：JSON 落盘，跨进程保留
function Import-FailCounts {
    $counts = @{}
    if (-not (Test-Path $StateFile)) { return $counts }
    try {
        $saved = Get-Content -Path $StateFile -Raw | ConvertFrom-Json
        foreach ($prop in $saved.PSObject.Properties) {
            $counts[$prop.Name] = [int]$prop.Value
        }
    } catch {
        Write-Log "看门狗计数文件解析失败，各服务按 0 重新计数: $_"
    }
    return $counts
}

function Export-FailCounts($counts) {
    try {
        $counts | ConvertTo-Json | Set-Content -Path $StateFile -Encoding UTF8
    } catch {
        Write-Log "看门狗计数文件写入失败: $_"
    }
}

function Test-Docker {
    docker info --format "{{.ServerVersion}}" 2>$null | Out-Null
    return ($LASTEXITCODE -eq 0)
}

function Test-Http([string]$url) {
    try {
        $response = Invoke-WebRequest -Uri $url -TimeoutSec 10 -UseBasicParsing -ErrorAction Stop
        return ($response.StatusCode -ge 200 -and $response.StatusCode -lt 400)
    } catch {
        return $false
    }
}

function Test-Container([string]$container) {
    $status = docker inspect -f "{{.State.Status}}" $container 2>$null
    return ($status -eq "running")
}

function Invoke-Compose([string[]]$composeArgs) {
    & docker compose -f $ComposeFile @composeArgs 2>&1 | Out-Null
    return $LASTEXITCODE
}

# 确保日志目录存在
New-Item -ItemType Directory -Force -Path $LogDir | Out-Null

# 告警 Webhook：命令行参数 > 环境变量 > deploy 目录下的 feishu-webhook.txt。
# 计划任务注册命令里不写密钥（密钥不该进版本库），由部署机本地放文件或配环境变量。
if (-not $FeishuWebhook) { $FeishuWebhook = $env:FRUITSHORTS_FEISHU_WEBHOOK }
if (-not $FeishuWebhook) {
    $webhookFile = Join-Path $PSScriptRoot "feishu-webhook.txt"
    if (Test-Path $webhookFile) {
        $FeishuWebhook = (Get-Content -Path $webhookFile -Raw -ErrorAction SilentlyContinue)
        if ($FeishuWebhook) { $FeishuWebhook = $FeishuWebhook.Trim() }
    }
}
if (-not $FeishuWebhook) {
    Write-Log "未配置飞书 Webhook（参数/环境变量/feishu-webhook.txt 均为空），告警只写本地日志"
}

# Docker Desktop 登录后偶尔尚未就绪，先等待并尝试拉起。
# 注意：本脚本以 SYSTEM 身份运行，绝不能直接 Start-Process Docker Desktop.exe。
# WSL 不支持本地系统账户运行（WSL_E_LOCAL_SYSTEM_NOT_SUPPORTED），
# 以 SYSTEM 启动会把 docker-desktop 发行版搞成僵死状态（VHD 已挂载无法终止），
# 结果是登录用户会话里的 Docker Desktop 也永远起不来。
# 因此改为触发以登录用户身份运行的 FruitShorts-DockerDesktop 计划任务。
if (-not (Test-Docker)) {
    Write-Log "Docker 未就绪，尝试通过用户会话启动 Docker Desktop"
    $desktopTask = "FruitShorts-DockerDesktop"
    try {
        # Docker Desktop.exe 是任务进程树的一部分，GUI 活着时任务一直是 Running，
        # 直接 Start-ScheduledTask 会被 IgnoreNew 忽略，所以先结束旧实例再拉起。
        $t = Get-ScheduledTask -TaskName $desktopTask -ErrorAction Stop
        if ($t.State -eq "Running") {
            Stop-ScheduledTask -TaskName $desktopTask -ErrorAction SilentlyContinue
            Start-Sleep -Seconds 5
        }
        Start-ScheduledTask -TaskName $desktopTask -ErrorAction Stop
    } catch {
        Write-Log "触发 Docker Desktop 启动任务失败: $_"
    }

    for ($i = 0; $i -lt 18; $i++) {
        Start-Sleep -Seconds 5
        if (Test-Docker) { break }
    }
}

if (-not (Test-Docker)) {
    Write-Log "Docker 在 90 秒内未就绪，跳过本轮检查"
    Send-Alert "服务异常" "Docker Desktop 无法启动，请人工检查桌面机。"
    exit 1
}

# 健康检查定义：名称 → 检查方式
$checks = @(
    @{ Name = "app-api";    Type = "http";     Url = "http://127.0.0.1:8081/healthz"; Service = "app-api"; Container = "fruitshorts-app-api" },
    @{ Name = "admin-api";  Type = "http";     Url = "http://127.0.0.1:8080/healthz"; Service = "admin-api"; Container = "fruitshorts-admin-api" },
    @{ Name = "frontend";   Type = "frontend"; Url = "http://127.0.0.1:3005/dist-dev/" },
    @{ Name = "Grafana";    Type = "http";     Url = "http://127.0.0.1:3000/api/health"; Service = "grafana"; Container = "fruitshorts-grafana" },
    @{ Name = "PostgreSQL"; Type = "docker";   Service = "db"; Container = "fruitshorts-db" },
    @{ Name = "Redis";      Type = "docker";   Service = "redis"; Container = "fruitshorts-redis" },
    @{ Name = "Prometheus"; Type = "http";     Url = "http://127.0.0.1:9090/-/healthy"; Service = "prometheus"; Container = "fruitshorts-prometheus" }
)

# 跟踪每个服务的连续失败次数（跨进程从状态文件恢复）
$failCounts = Import-FailCounts

foreach ($check in $checks) {
    $name = $check.Name
    $healthy = $false

    if ($check.Type -eq "http") {
        $healthy = Test-Http $check.Url
    } elseif ($check.Type -eq "frontend") {
        $healthy = Test-Http $check.Url
    } else {
        $healthy = Test-Container $check.Container
    }

    if ($healthy) {
        if ($failCounts[$name] -gt 0) {
            Write-Log "$name 恢复正常（此前连续失败 $($failCounts[$name]) 次）"
            Send-Alert "服务恢复" "$name 已恢复正常"
        }
        $failCounts[$name] = 0
    } else {
        if ($null -eq $failCounts[$name]) {
            $failCounts[$name] = 0
        }
        $failCounts[$name] = $failCounts[$name] + 1
        $count = $failCounts[$name]
        Write-Log "$name 不健康（第 $count 次）"

        if ($check.Type -eq "frontend") {
            Write-Log "$name 重启计划任务 $FrontendTask"
            Stop-ScheduledTask -TaskName $FrontendTask -ErrorAction SilentlyContinue
            Start-Sleep -Seconds 2
            Start-ScheduledTask -TaskName $FrontendTask -ErrorAction SilentlyContinue
            Start-Sleep -Seconds 6
            $healthy = Test-Http $check.Url
        } elseif ($check.Type -eq "http") {
            Write-Log "$name 重启 Compose 服务 $($check.Service)"
            Invoke-Compose @("restart", $check.Service) | Out-Null
            Start-Sleep -Seconds 12
            $healthy = Test-Http $check.Url

            if (-not $healthy) {
                Write-Log "$name 重启后仍不健康，执行 compose up -d"
                Invoke-Compose @("up", "-d", $check.Service) | Out-Null
            }
        } else {
            Write-Log "$name 拉起容器 $($check.Container)"
            docker start $check.Container 2>&1 | Out-Null
            Start-Sleep -Seconds 5
            $healthy = Test-Container $check.Container

            if (-not $healthy) {
                Write-Log "$name 启动失败，执行 compose up -d"
                Invoke-Compose @("up", "-d", $check.Service) | Out-Null
            }
        }

        # 连续失败达到上限 → 告警。计数会跨进程累积，所以只在首次达阈值和
        # 之后每 30 轮（约 1 小时）提醒一次，避免每 2 分钟刷屏。
        if (-not $healthy -and $count -ge $MaxRestarts -and
                ($count -eq $MaxRestarts -or $count % 30 -eq 0)) {
            Send-Alert "服务异常" "$name 已连续 $count 次不健康，已尝试重启。请人工介入检查。"
            Write-Log "$name 连续 $count 次失败，已发告警"
        } elseif ($healthy) {
            Write-Log "$name 已自动恢复"
        }
    }
}

# 磁盘检查：超过 85% 告警
$drive = (Get-PSDrive C -ErrorAction SilentlyContinue)
if ($drive) {
    $pct = [math]::Round(($drive.Used / ($drive.Used + $drive.Free)) * 100)
    if ($pct -gt 85) {
        Write-Log "磁盘使用率 ${pct}%（超过 85%）"
        Send-Alert "磁盘告警" "C 盘使用率 ${pct}%，请清理日志或扩容"
    }
}

# 本轮结果落盘，供下一轮（2 分钟后的新进程）继续累加
Export-FailCounts $failCounts