<#
This script monitors specified folder and when new file is copied there it transfers this file to specified Azure blob storage.
After transfer script moves files to movedfiles subfolder.
#>

param
(
	[Parameter(Mandatory=$true, HelpMessage = "Azure storage account name which will be used for storing files")]
	[string]$azureStorageAccountName,
	[Parameter(Mandatory=$true, HelpMessage = "Azure storage account key")]
	[string]$azureStorageAccountKey,
	
	[Parameter(Mandatory=$true, HelpMessage = "Folder on local file system which should be monitored by script")]
	[string]$pathToMonitor,
	[Parameter(Mandatory=$true, HelpMessage = "Prefixes of the files which should be moved to Azure blob storage")]
	[string]$fileNamePrefix,
	[Parameter(Mandatory=$true, HelpMessage = "Extensions of the files which should be moved to Azure blob storage")]
	[string]$fileNameExtension
)

# logging
function Log-File {
	param (
		$msg
	)

	$msg = [System.DateTime]::Now.ToString("yyyy.MM.dd HH:mm:ss.ffff") + "`t" + $msg
	($msg) | Out-File $global:logFile -Append
}

function Log-Info {
	param (
		$msg
	)

    Write-Host $msg -foregroundcolor green
    Log-File $msg
}

function Log-Warn {
	param (
		$msg
	)

    Write-Host $msg -foregroundcolor yellow
    Log-File $msg
}

function Log-Error {
	param (
		$msg
	)

    Write-Host $msg -foregroundcolor red
    Log-File $msg
}

# files processing
function Move-File-To-Azure {
	param (
		$fileName,
		$filePath,
		$timestamp
	)
	Log-Info ("Process file $filePath")
	if (!(Test-Path $filePath -PathType Leaf)) {
		Log-Error ("File $filePath doesn't exist")
		return
	}
	
	Log-Info ("Open Azure session")
	$ctx = New-AzureStorageContext -StorageAccountName $azureStorageAccountName -StorageAccountKey $azureStorageAccountKey
	$azureStorageContainerName = "idp"
	Log-Info ("Connect to container $azureStorageContainerName")
	$container = Get-AzureStorageContainer -Name $azureStorageContainerName -Context $ctx -ErrorAction SilentlyContinue
	if (!$container) {
		Log-Info ("Container $azureStorageContainerName doesn't exist. Create it")
		New-AzureStorageContainer -Name $azureStorageContainerName -Context $ctx -Permission Blob
		Log-Info ("Container $azureStorageContainerName is successfully created")
	}
	
	$blobName = $timestamp + "/" + $fileName
	Log-Info ("Transfering file $fileName to Azure blob storage $blobName...")
	Set-AzureStorageBlobContent -File $filePath -Container $azureStorageContainerName -Blob $blobName -Context $ctx
	Log-Info ("File has been sucessfully transfered")
	
	Log-Info ("Move $fileName file to $global:movedFiles")
	Move-Item -Path $filePath -Destination $global:movedFiles
	Log-Info ("File has been successfully moved")
}

# initialization
$currentDir = $PSScriptRoot
Set-Location $currentDir

$logFolder = [System.IO.Path]::Combine($PSScriptRoot, "logs")
if (!(Test-Path $logFolder)) {
	New-Item -ItemType Directory -Force -Path $logFolder
}
$timestamp = [System.DateTime]::Now.ToString("yyyyMMddHHmmss")
$global:logFile = [System.IO.Path]::Combine($logFolder, [System.String]::Format("taloyhtio_idp_{0}.txt", $timestamp))

$global:movedFiles = [System.IO.Path]::Combine($PSScriptRoot, "movedfiles/" + $timestamp)
if (!(Test-Path $global:movedFiles)) {
	New-Item -ItemType Directory -Force -Path $global:movedFiles
}

Log-Info ("Start new session")

if (!(Test-Path $pathToMonitor)) {
	Log-Error ("Path $pathToMonitor doesn't exist")
	return
}

if (!$pathToMonitor.EndsWith("/") -and !$pathToMonitor.EndsWith("\")) {
	$pathToMonitor += "/"
}

$files = Get-ChildItem $pathToMonitor
if ($files.Count -eq 0) {
	Log-Info ("Folder $pathToMonitor is empty")
	return
}

if (!$fileNameExtension.StartsWith(".")) {
	$fileNameExtension = "." + $fileNameExtension
}

foreach ($f in $files) {
	if (!$f.Name.ToLower().StartsWith($fileNamePrefix)) {
		Log-Warn ("File $($f.Name) doesn't start with $fileNamePrefix. Skip it")
		continue
	}

	if ($f.Extension.ToLower() -ne $fileNameExtension.ToLower()) {
		Log-Warn ("File $($f.Name) doesn't have extension $fileNameExtension. Skip it")
		continue
	}

	
	Move-File-To-Azure $f.Name $f.FullName $timestamp
}