# lib/common.ps1 — app-cli 公共函数
#
# 约定：调用方脚本先设置 $CliRoot（app-cli 根目录），再点源引入本文件：
#   $CliRoot = Split-Path -Parent $PSScriptRoot
#   . (Join-Path $CliRoot 'lib\common.ps1')
#
# 本文件不启动任何服务，只提供：路径解析 / 配置读取 / 端口探测 / 进程登记 / HTTP 探测。
# 兼容 Windows PowerShell 5.1 与 PowerShell 7。

if (-not $CliRoot) { throw 'common.ps1：调用方必须先设置 $CliRoot' }

$script:AppCliRoot = $CliRoot
$LogDir = Join-Path $CliRoot '.logs'
$RunDir = Join-Path $CliRoot '.run'
$BinDir = Join-Path $CliRoot '.bin'
foreach ($d in @($LogDir, $RunDir, $BinDir)) {
    if (-not (Test-Path $d)) { New-Item -ItemType Directory -Path $d -Force | Out-Null }
}

# ---------------------------------------------------------------- 输出

function Write-Step { param([string]$Msg) Write-Host "==> $Msg" -ForegroundColor Cyan }
function Write-Ok   { param([string]$Msg) Write-Host "  [OK] $Msg" -ForegroundColor Green }
function Write-Note { param([string]$Msg) Write-Host "  [--] $Msg" -ForegroundColor Gray }
function Write-Warn { param([string]$Msg) Write-Host "  [!!] $Msg" -ForegroundColor Yellow }
function Write-Fail { param([string]$Msg) Write-Host "  [XX] $Msg" -ForegroundColor Red }

# ---------------------------------------------------------------- 配置

# Import-LocalEnv：读取 KEY=VALUE 形式的本地配置（config/local.env）。
# 支持 # 注释、空行、值两侧引号；文件不存在时返回空表（全部走默认值）。
function Import-LocalEnv {
    param([string]$Path)
    $map = @{}
    if (-not (Test-Path $Path)) { return $map }
    foreach ($line in (Get-Content -Path $Path -Encoding UTF8)) {
        $t = $line.Trim()
        if ($t -eq '' -or $t.StartsWith('#')) { continue }
        $i = $t.IndexOf('=')
        if ($i -lt 1) { continue }
        $k = $t.Substring(0, $i).Trim()
        $v = $t.Substring($i + 1).Trim()
        if ($v.Length -ge 2 -and $v.StartsWith('"') -and $v.EndsWith('"')) {
            $v = $v.Substring(1, $v.Length - 2)
        }
        $map[$k] = $v
    }
    return $map
}

# Get-Setting：取本地配置项，缺省或空串时回落 $Default。
function Get-Setting {
    param($EnvMap, [string]$Key, [string]$Default)
    if ($EnvMap -and $EnvMap.ContainsKey($Key)) {
        $v = $EnvMap[$Key]
        if ($v -ne '') { return $v }
    }
    return $Default
}

# Get-YamlScalar：从 yml 里取「某个顶层 section 下某个键」的标量值（只处理本项目用到的简单结构）。
function Get-YamlScalar {
    param([string]$Path, [string]$Section, [string]$Key)
    if (-not (Test-Path $Path)) { return '' }
    $inSection = $false
    foreach ($line in (Get-Content -Path $Path -Encoding UTF8)) {
        if ($line -match '^([A-Za-z_][A-Za-z0-9_]*)\s*:') {
            $inSection = ($Matches[1] -eq $Section)
            continue
        }
        if (-not $inSection) { continue }
        if ($line -match '^\s+([A-Za-z_][A-Za-z0-9_]*)\s*:\s*(.*)$') {
            if ($Matches[1] -ne $Key) { continue }
            $v = $Matches[2]
            $h = $v.IndexOf('#')
            if ($h -ge 0) { $v = $v.Substring(0, $h) }
            return $v.Trim().Trim('"').Trim("'")
        }
    }
    return ''
}

# ---------------------------------------------------------------- 仓库定位

# Resolve-Services：确定 backend / frontend / vision 三个仓库的实际路径。
# 优先级：config/local.env 显式配置 > 与 app-cli 同级的约定目录。
# 用「标记文件」校验，避免路径写错后启动到一个空目录。
function Resolve-Services {
    param($EnvMap, [string]$Root)
    $parent = Split-Path -Parent $Root

    $defs = @(
        @{ Name = 'backend';  Key = 'BACKEND_DIR';  Default = (Join-Path $parent 'backend');      Marker = 'cmd\server\main.go' },
        @{ Name = 'frontend'; Key = 'FRONTEND_DIR'; Default = (Join-Path $parent 'test\test');    Marker = 'astro.config.mjs' },
        @{ Name = 'vision';   Key = 'VISION_DIR';   Default = (Join-Path $parent 'fashion-siglip'); Marker = 'app.py' }
    )

    $result = @{}
    foreach ($d in $defs) {
        $path = Get-Setting $EnvMap $d.Key $d.Default
        $path = $path.TrimEnd('\', '/')
        $marker = Join-Path $path $d.Marker
        $result[$d.Name] = [PSCustomObject]@{
            Name    = $d.Name
            Path    = $path
            Marker  = $marker
            IsValid = (Test-Path $marker)
        }
    }
    return [PSCustomObject]@{
        Backend  = $result['backend']
        Frontend = $result['frontend']
        Vision   = $result['vision']
    }
}

# ---------------------------------------------------------------- 端口与进程

function Test-PortInUse {
    param([int]$Port)
    $c = Get-NetTCPConnection -LocalPort $Port -State Listen -ErrorAction SilentlyContinue
    return [bool]$c
}

function Get-PortOwnerPid {
    param([int]$Port)
    $c = Get-NetTCPConnection -LocalPort $Port -State Listen -ErrorAction SilentlyContinue | Select-Object -First 1
    if (-not $c) { return 0 }
    return [int]$c.OwningProcess
}

function Get-PidFile {
    param([string]$Name)
    return (Join-Path $RunDir ($Name + '.pid'))
}

# Save-ServicePid：登记本脚本启动的进程，供 stop.ps1 / status.ps1 使用。
function Save-ServicePid {
    param([string]$Name, [int]$ProcessId)
    Set-Content -Path (Get-PidFile $Name) -Value $ProcessId -Encoding ASCII
}

# Get-ServicePid：读取登记的 PID；进程已不存在时清掉登记并返回 0。
function Get-ServicePid {
    param([string]$Name)
    $f = Get-PidFile $Name
    if (-not (Test-Path $f)) { return 0 }
    $raw = (Get-Content -Path $f -ErrorAction SilentlyContinue | Select-Object -First 1)
    $id = 0
    if ($raw -and [int]::TryParse($raw.Trim(), [ref]$id)) {
        $p = Get-Process -Id $id -ErrorAction SilentlyContinue
        if ($p) { return $id }
    }
    Remove-Item $f -Force -ErrorAction SilentlyContinue
    return 0
}

# Stop-PidTree：杀掉进程及其子进程（node/go 会派生，必须连树一起杀）。
function Stop-PidTree {
    param([int]$ProcessId)
    if ($ProcessId -le 0) { return $false }
    $p = Get-Process -Id $ProcessId -ErrorAction SilentlyContinue
    if (-not $p) { return $false }
    & taskkill.exe /PID $ProcessId /T /F 2>&1 | Out-Null
    Start-Sleep -Milliseconds 300
    return $true
}

# Stop-NamedService：按登记名停服务，顺带清掉 PID 文件。
function Stop-NamedService {
    param([string]$Name)
    $id = Get-ServicePid $Name
    if ($id -le 0) { return $false }
    $killed = Stop-PidTree $id
    Remove-Item (Get-PidFile $Name) -Force -ErrorAction SilentlyContinue
    return $killed
}

# Start-LoggedProcess：后台启动并重定向日志，成功后登记 PID。
function Start-LoggedProcess {
    param(
        [string]$Name,
        [string]$FilePath,
        [string[]]$ArgumentList = @(),
        [string]$WorkingDirectory
    )
    $out = Join-Path $LogDir ($Name + '.log')
    $err = Join-Path $LogDir ($Name + '.err.log')
    foreach ($f in @($out, $err)) {
        if (Test-Path $f) { Remove-Item $f -Force -ErrorAction SilentlyContinue }
    }
    # 注意：Start-Process 的 -ArgumentList 传空数组会抛参数校验异常（"该参数为 Null、为空"），
    # 所以无参进程（例如后端的编译产物）必须整个不传这个参数。
    $params = @{
        FilePath               = $FilePath
        WorkingDirectory       = $WorkingDirectory
        RedirectStandardOutput = $out
        RedirectStandardError  = $err
        WindowStyle            = 'Hidden'
        PassThru               = $true
    }
    if ($null -ne $ArgumentList -and $ArgumentList.Count -gt 0) {
        $params['ArgumentList'] = $ArgumentList
    }
    $p = Start-Process @params
    Save-ServicePid -Name $Name -ProcessId $p.Id
    return $p
}

# ---------------------------------------------------------------- HTTP

# Test-TcpConnect：TCP 连通性探测（数据库这类非 HTTP 服务用）。
function Test-TcpConnect {
    param([string]$ComputerName, [int]$Port, [int]$TimeoutMs = 3000)
    $client = New-Object System.Net.Sockets.TcpClient
    try {
        $iar = $client.BeginConnect($ComputerName, $Port, $null, $null)
        if (-not $iar.AsyncWaitHandle.WaitOne($TimeoutMs)) { return $false }
        $client.EndConnect($iar)
        return $true
    } catch {
        return $false
    } finally {
        $client.Close()
    }
}

# Wait-HttpOk：轮询直到返回 2xx/3xx，超时返回 $false。
function Wait-HttpOk {
    param([string]$Url, [int]$TimeoutSec = 90)
    $deadline = (Get-Date).AddSeconds($TimeoutSec)
    while ((Get-Date) -lt $deadline) {
        try {
            $r = Invoke-WebRequest -Uri $Url -UseBasicParsing -TimeoutSec 5 -ErrorAction Stop
            if ($r.StatusCode -ge 200 -and $r.StatusCode -lt 400) { return $true }
        } catch { }
        Start-Sleep -Milliseconds 700
    }
    return $false
}

# Get-CorsOrigin：带 Origin 头请求一次，返回后端回显的 Access-Control-Allow-Origin。
# 返回空串表示后端没放行该来源（浏览器会整条拦掉，页面表现为「无数据」）。
function Get-CorsOrigin {
    param([string]$Url, [string]$Origin)
    try {
        $r = Invoke-WebRequest -Uri $Url -UseBasicParsing -TimeoutSec 8 -Headers @{ Origin = $Origin } -ErrorAction Stop
        $acao = $r.Headers['Access-Control-Allow-Origin']
        if ($acao -is [array]) { $acao = $acao[0] }
        if ($null -eq $acao) { return '' }
        return [string]$acao
    } catch {
        return ''
    }
}

# ---------------------------------------------------------------- 日志

function Show-LogTail {
    param([string]$Name, [int]$Lines = 15)
    foreach ($suffix in @('.log', '.err.log')) {
        $f = Join-Path $LogDir ($Name + $suffix)
        if (-not (Test-Path $f)) { continue }
        $content = Get-Content -Path $f -Tail $Lines -ErrorAction SilentlyContinue
        if (-not $content) { continue }
        Write-Host ("  --- " + $Name + $suffix + " ---") -ForegroundColor DarkGray
        foreach ($l in $content) { Write-Host ("  " + $l) -ForegroundColor DarkGray }
    }
}

# Get-ServiceStatus：给 status.ps1 用的单服务状态。
function Get-ServiceStatus {
    param([string]$Name, [int]$Port, [string]$HealthUrl)
    $id = Get-ServicePid $Name
    $listening = Test-PortInUse $Port
    $owner = 0
    if ($listening) { $owner = Get-PortOwnerPid $Port }
    $healthy = $false
    if ($listening -and $HealthUrl -ne '') { $healthy = Wait-HttpOk -Url $HealthUrl -TimeoutSec 3 }
    return [PSCustomObject]@{
        Name      = $Name
        Port      = $Port
        Pid       = $id
        Listening = $listening
        OwnerPid  = $owner
        Healthy   = $healthy
    }
}