param(
    [Parameter(Mandatory = $true)][string]$EnvPath,
    [Parameter(Mandatory = $true)][string]$ProjectRoot
)

$ErrorActionPreference = "Stop"
$migrationsDir = if ([string]::IsNullOrWhiteSpace($env:UPDATE_ENV_MIGRATIONS_DIR)) {
    Join-Path $ProjectRoot "scripts\update-env.d"
} else {
    $env:UPDATE_ENV_MIGRATIONS_DIR
}

if (-not (Test-Path $EnvPath -PathType Leaf)) {
    throw "环境配置文件不存在: $EnvPath"
}
if (-not (Test-Path $migrationsDir -PathType Container)) {
    Write-Host "ℹ️ 未发现环境配置迁移目录，跳过"
    return
}

function Get-EnvValue {
    param([string]$Path, [string]$Key)
    foreach ($line in [System.IO.File]::ReadAllLines($Path)) {
        if ($line.StartsWith("$Key=")) {
            return $line.Substring($Key.Length + 1).Trim().Trim('"').Trim("'")
        }
    }
    return ""
}

function Set-EnvValue {
    param([string]$Path, [string]$Key, [string]$Value)
    $output = New-Object System.Collections.Generic.List[string]
    $replaced = $false
    foreach ($line in [System.IO.File]::ReadAllLines($Path)) {
        if ($line.StartsWith("$Key=")) {
            if (-not $replaced) {
                $output.Add("$Key=$Value")
                $replaced = $true
            }
        } else {
            $output.Add($line)
        }
    }
    if (-not $replaced) { $output.Add("$Key=$Value") }
    [System.IO.File]::WriteAllLines($Path, $output, (New-Object System.Text.UTF8Encoding($false)))
}

function Set-EnvDefault {
    param([string]$Key, [string]$Value)
    if (-not [string]::IsNullOrWhiteSpace((Get-EnvValue -Path $EnvPath -Key $Key))) { return }
    Set-EnvValue -Path $EnvPath -Key $Key -Value $Value
    Write-Host "   ✓ 已补充环境配置: $Key"
}

function Add-EnvListItem {
    param([string]$Key, [string]$Item)
    $current = Get-EnvValue -Path $EnvPath -Key $Key
    $items = @($current.Split(',') | ForEach-Object { $_.Trim() } | Where-Object { $_ })
    if ($items -contains $Item) { return }
    $next = if ($items.Count -eq 0) { $Item } else { (@($items) + $Item) -join ',' }
    Set-EnvValue -Path $EnvPath -Key $Key -Value $next
    Write-Host "   ✓ 已补充环境配置项: $Key"
}

$manifests = @(Get-ChildItem -Path $migrationsDir -Filter "*.env" -File | Sort-Object Name)
if ($manifests.Count -eq 0) {
    Write-Host "ℹ️ 未发现环境配置迁移文件，跳过"
    return
}

foreach ($manifest in $manifests) {
    $lineNumber = 0
    foreach ($rawLine in [System.IO.File]::ReadAllLines($manifest.FullName)) {
        $lineNumber++
        $line = $rawLine.TrimEnd("`r")
        if ([string]::IsNullOrWhiteSpace($line) -or $line.StartsWith('#')) { continue }
        if ($line -match '^@skip-if\s+[A-Z][A-Z0-9_]*=.+$') { continue }
        if ($line -notmatch '^[A-Z][A-Z0-9_]*(\+)?=.+$') {
            throw "无效的环境配置迁移: $($manifest.FullName):$lineNumber"
        }
    }
}

foreach ($manifest in $manifests) {
    $skipManifest = $false
    foreach ($rawLine in [System.IO.File]::ReadAllLines($manifest.FullName)) {
        $line = $rawLine.TrimEnd("`r")
        if ($line -match '^@skip-if\s+([A-Z][A-Z0-9_]*)=(.+)$') {
            if ((Get-EnvValue -Path $EnvPath -Key $Matches[1]) -eq $Matches[2]) {
                Write-Host "ℹ️ 保留现有更新模式，跳过环境配置迁移: $($manifest.Name)"
                $skipManifest = $true
                break
            }
        }
    }
    if ($skipManifest) { continue }
    Write-Host "📝 应用环境配置迁移: $($manifest.Name)"
    foreach ($rawLine in [System.IO.File]::ReadAllLines($manifest.FullName)) {
        $line = $rawLine.TrimEnd("`r")
        if ([string]::IsNullOrWhiteSpace($line) -or $line.StartsWith('#')) { continue }
        if ($line.StartsWith('@skip-if')) { continue }
        if ($line.Contains('+=')) {
            $parts = $line.Split(@('+='), 2, [System.StringSplitOptions]::None)
            Add-EnvListItem -Key $parts[0] -Item $parts[1]
        } else {
            $parts = $line.Split(@('='), 2, [System.StringSplitOptions]::None)
            Set-EnvDefault -Key $parts[0] -Value $parts[1]
        }
    }
}