<#
  .SYNOPSIS
  Installs Antrea-Agent service.

  .PARAMETER Namespace
  ExternalNode Namespace to be used.

  .PARAMETER BinaryPath
  Specifies the path of the antrea-agent binary to be used.

  .PARAMETER ConfigPath
  Specifies the path of the antrea-agent configuration file to be used.

  .PARAMETER KubeConfigPath
  Specifies the path of the kubeconfig to access K8s API Server.

  .PARAMETER AntreaKubeConfigPath
  Specifies the path of the kubeconfig to access Antrea API Server.

  .PARAMETER NodeName
  Specifies the ExternalNode name to be used by the antrea-agent.

  .PARAMETER OVSBridge
  Specifies the OVS bridge name.

  .PARAMETER InstallDir
  The target installation directory. The default path is "C:\antrea-agent".
#>
Param(
    [parameter(Mandatory = $true)] [string] $Namespace,
    [parameter(Mandatory = $true)] [string] $BinaryPath,
    [parameter(Mandatory = $true)] [string] $ConfigPath,
    [parameter(Mandatory = $true)] [string] $KubeConfigPath,
    [parameter(Mandatory = $true)] [string] $AntreaKubeConfigPath,
    [parameter(Mandatory = $false)] [string] $NodeName = $(hostname),
    [parameter(Mandatory = $false)] [string] $OVSBridge = "br-int",
    [parameter(Mandatory = $false)] [string] $InstallDir = "C:\antrea-agent"
)

$ErrorActionPreference = "Stop"
$Powershell = (Get-Command powershell).Source
$PowershellArgs = "-ExecutionPolicy Bypass -NoProfile -File"

# Antrea paths
$AntreaAgentConfDir = [io.path]::combine($InstallDir, "conf")
$AntreaAgentLogDir = [io.path]::combine($InstallDir, "logs")
$AntreaAgentConfPath = [io.path]::combine($AntreaAgentConfDir, "antrea-agent.conf")
$LogFile = [io.path]::combine($AntreaAgentLogDir, "antrea-agent-service.log")
$StartAntreaAgentScript = ""

# Constants
$AntreaAgent = "antrea-agent"
$OVSServices = "ovsdb-server", "ovs-vswitchd"
$OVSVswitchd = "ovs-vswitchd"
$K8sKubeconfig = "antrea-agent.kubeconfig"
$AntreaKubeconfig = "antrea-agent.antrea.kubeconfig"
$Bridge = "ovsBridge"
$ExternalNodeNamespace = "externalNodeNamespace"
$Kubeconfig = "kubeconfig"

# List of supported OS versions, verified by antrea
# Versions are named like Major.Minor.Build
$SupportedVersions = @("10.0.17763")

function Log($Info) {
    $time = $(get-date -Format g)
    "$time $Info " | Tee-Object $LogFile -Append | Write-Host
}

function ServiceExists($ServiceName) {
    If (Get-Service $ServiceName -ErrorAction SilentlyContinue) {
        return $true
    }
    return $false
}

function CheckSupportedVersions() {
    Log "Checking supported Windows OS versions"
    $OSVersion = [System.Environment]::OSVersion.Version
    $Version = $OSVersion.Major.ToString() + "." + $OSVersion.Minor.ToString() + "." + $OSVersion.Build.ToString()
    foreach ($v in $SupportedVersions) {
        if ($v -eq $Version) {
            return
        }
    }
    Log "Error only Windows $SupportedVersions is supported"
    exit 1
}

function PrintPrerequisites() {
    Write-Host "Please execute these commands to enable Hyper-V"
    Write-Host "Install-WindowsFeature Hyper-V-Powershell"
    Write-Host "Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V -All -NoRestart"
    exit 1
}

function CheckPrerequisites() {
    CheckSupportedVersions
    $valid = $true
    Log "Check Hyper-v feature is enabled"
    if ((Get-WindowsOptionalFeature -FeatureName "Microsoft-Hyper-V" -Online).State -eq "Disabled") {
        Log "Windows optional feature Microsoft-Hyper-V is disabled"
        $valid = $false
    }

    if ((Get-WindowsFeature -Name "Hyper-V-Powershell").InstallState -ne "Installed") {
        Log "Windows feature Hyper-V-Powershell is not installed"
        $valid = $false
    }

    if ($valid -eq $false) {
        PrintPrerequisites
    }

    Log "Check OVS services are installed"
    foreach ($daemon in $OVSServices) {
        If (-Not (ServiceExists($daemon))) {
            Log "Service $daemon does not exist."
            exit 1
        }
    }
}

function SetupInstallDir() {
    if (-Not (Test-Path $AntreaAgentConfDir)) {
        New-Item $AntreaAgentConfDir -type directory -Force | Out-Null
    }

    if (-Not (Test-Path $AntreaAgentLogDir)) {
        New-Item $AntreaAgentLogDir -type directory -Force | Out-Null
    }
}

function CopyAntreaAgentFiles() {
    if ( -Not (Test-Path $BinaryPath)) {
        Log "$BinaryPath file not found"
        exit 1
    }
    Log "Copying $BinaryPath to $InstallDir"
    Copy-Item -Path "$BinaryPath" -Destination $InstallDir -Force |  Out-Null

    if ( -Not (Test-Path $KubeConfigPath)) {
        Log "$KubeConfigPath file not found"
        exit 1
    }
    Log "Copying $KubeConfigPath to $AntreaAgentConfDir"
    Copy-Item -Path "$KubeConfigPath" -Destination "$AntreaAgentConfDir\$K8sKubeconfig" -Force

    if ( -Not (Test-Path $AntreaKubeConfigPath)) {
        Log "$AntreaKubeConfigPath file not found"
        exit 1
    }
    Log "Copying $AntreaKubeConfigPath to $AntreaAgentConfDir"
    Copy-Item -Path "$AntreaKubeConfigPath" -Destination "$AntreaAgentConfDir\$AntreaKubeconfig" -Force
}

function UpdateAgentConf() {
    if ( -Not (Test-Path $ConfigPath)) {
        Log "$ConfigPath file not found"
        exit 1
    }
    New-Item $AntreaAgentConfPath -type file -Force | Out-Null
    $file = Get-Content $ConfigPath
    foreach ($line in $file) {
        if ($line -like "*$Kubeconfig") {
            $key, $val = $line.split(":", 2).trim()
            $newval = "${AntreaAgentConfDir}\${val}"
            Log "Updating $AntreaAgentConfPath with ${key}: ${newval}"
            [System.IO.File]::AppendAllText($AntreaAgentConfPath, "  ${key}: ${newval}" +
                    ([Environment]::NewLine))
        } elseif ($line -like "*$ExternalNodeNamespace*") {
            Log "Updating $AntreaAgentConfPath with ${ExternalNodeNamespace}: ${Namespace}"
            [System.IO.File]::AppendAllText($AntreaAgentConfPath, "  ${ExternalNodeNamespace}: ${Namespace}" +
                    ([Environment]::NewLine))
        } elseif ($line -like "*$Bridge*") {
            Log "Updating $AntreaAgentConfPath with ${Bridge}: ${OVSBridge}"
            [System.IO.File]::AppendAllText($AntreaAgentConfPath, "${Bridge}: ${OVSBridge}" +
                    ([Environment]::NewLine))
        } else {
            [System.IO.File]::AppendAllText($AntreaAgentConfPath, $line +
                    ([Environment]::NewLine))
        }
    }
}

function CreateAntreaAgentStartupScript() {
    $Script:StartAntreaAgentScript = "$AntreaAgentConfDir\Start-AntreaAgent.ps1"
    $StartAntreaAgentScriptContent = '
Param(
    [parameter(Mandatory = $true)] [string] $OVSBridge,
    [parameter(Mandatory = $true)] [string] $InstallDir
)

$AntreaSwitch = "antrea-switch"
$AntreaAgentConfDir = [io.path]::combine($InstallDir, "conf")
$AntreaAgentLogDir = [io.path]::combine($InstallDir, "logs")
$AntreaAgentConfPath = [io.path]::combine($AntreaAgentConfDir, "antrea-agent.conf")
$AntreaAgentLogFile = [io.path]::combine($AntreaAgentLogDir, "antrea-agent.log")
$AntreaAgentPath = [io.path]::combine($InstallDir, "antrea-agent.exe")
$LogFile = [io.path]::combine($AntreaAgentLogDir, "antrea-agent-service.log")

function Log($Info) {
    $time = $(get-date -Format g)
    "$time $Info " | Tee-Object $LogFile -Append | Write-Host
}

function ClearOVSConfig() {
    Log "Deleting OVS bridge $OVSBridge"
    try {
        $adapterName = (Get-VMNetworkAdapter -ComputerName $(hostname.exe) -SwitchName $AntreaSwitch -ManagementOS).Name
        ovs-vsctl.exe del-br $OVSBridge
    }  catch {
        Log "Failed to get VMSwitch $AntreaSwitch, rc $_"
        exit 1
    }

    try {
        Remove-VMSwitch -ComputerName $(hostname.exe) $AntreaSwitch  -Force
    } catch {
        Log "Ignore error while removing VMSwitch, rc $_"
    }

    try {
        Rename-NetAdapter -Name "$adapterName~" -NewName "$adapterName"
    }  catch {
        Log "Failed to rename network adapter $adapterName~ to $adapterName, rc $_"
        exit 1
    }
}

function CheckOVSConfigAndCleanup() {
    $bridges = ovs-vsctl list-br
    foreach ($br in $bridges) {
        if ($br -ne $OVSBridge) {
            continue
        }
        $ports = ovs-vsctl list-ports $OVSBridge
        foreach ($port in $ports) {
            $output = ovs-vsctl --no-headings --columns=error list interface "$port"
            if ($output -ne "[]") {
                ClearOVSConfig
                break
            }
        }
    }
}

function StartAntreaAgent() {
    $antreaAgentArgs = "--config $AntreaAgentConfPath --log_file $AntreaAgentLogFile --logtostderr=false"
    $cmd = "$AntreaAgentPath $antreaAgentArgs"
    Invoke-Expression $cmd
}

CheckOVSConfigAndCleanup
StartAntreaAgent
'
    Set-Content -Path $StartAntreaAgentScript -Value $StartAntreaAgentScriptContent
}

function ConfigureAntreaAgentService() {
    $AntreaAgentArgs = "$StartAntreaAgentScript -InstallDir $InstallDir -OVSBridge $OVSBridge"
    nssm install $AntreaAgent $Powershell $PowershellArgs $AntreaAgentArgs
    # Add OVS as a dependent service
    nssm set $AntreaAgent DependOnService $OVSVswitchd
}

function StartAntreaAgentService() {
    nssm start $AntreaAgent
}

SetupInstallDir
CheckPrerequisites
CopyAntreaAgentFiles
UpdateAgentConf
CreateAntreaAgentStartupScript
ConfigureAntreaAgentService
StartAntreaAgentService