backup_script_en.ps1

###############################################################################
############################ BackUp Script by WeoM ############################
###############################################################################
$version = "2.0"

#!WARNING! The script is simple, so any errors you make when editing configs are not checked.

################################### Configs ###################################

$target   = "D:\BackupFolderName\"        # the folder where the backups will be saved
$date     = Get-Date -Format "yyyy_MM_dd" # current date in format 2024_01_01
$filename = "backup_$date.7z"             # name of the resulting file
$pswd     = "" # optionally you can add a password to the archive, to do this you need to enter the desired password between ""

[bool]$logEnabled  = $false # to activate logging to file change $false to $true
[bool]$force       = $false # (silent mode) to create a backup without confirmation change $false to $true
$waitTimeInSeconds = 5      # time in seconds before closing the console window

##################################### Log #####################################

if($logEnabled){ Start-Transcript -Path "$target\logs\backup_$date.log" -Force }

###############################################################################

$path        = $PSScriptRoot # get the path to folder where the executable script is located: source.txt exclude.txt 7z.exe 7z.dll
$7z          = Join-Path -Path $path -ChildPath "7z.exe"
$sourceList  = Join-Path -Path $path -ChildPath "source.txt" # in source.txt add paths to folders and files for backup
$excludeList = Join-Path -Path $path -ChildPath "exclude.txt" # exclusions are added to exclude.txt
$scriptName  = "BackUp Script $version by WeoM"
#!WARNING! in source.txt and exclude.txt files it is necessary to use absolute paths because of the -spf2 key

################################## functions ##################################

#Load lib WinForms
Add-Type -AssemblyName System.Windows.Forms

function Get-Timestamp {
    return (Get-Date).ToString("dd.MM.yyyy HH:mm:ss")
}

function Get-MsgBox {
    param ( [Parameter(Mandatory, Position=0)] [string]$ErrorMessage )

    Write-Host $ErrorMessage -ForegroundColor Red
    [System.Windows.Forms.MessageBox]::Show("$ErrorMessage", "Error in `"$scriptName`"", [System.Windows.Forms.MessageBoxButtons]::OK, [System.Windows.Forms.MessageBoxIcon]::Error)
}

function Get-Broken7zList {
    <#
    .SYNOPSIS
    Reads a text file line by line, skips empty lines and #-comments, then checks each line for 7-Zip compatibility with -spf2 switch.

    .DESCRIPTION
    Validation rules:
    • Path must be absolute (e.g., C:\... or \\server\share).
    • Quotes around path are allowed.
    • "/" is auto-converted to "\".
    • Path must not contain invalid Windows characters.
    • File or directory must exist.
    • Duplicates are errors.
    • Invalid lines return as array with error reasons.

    .PARAMETER Path
    Path to file to read (e.g., "source.txt").

    .PARAMETER ThrowOnError
    If specified, the function will throw an exception if there are any invalid strings.

    .EXAMPLE
    $badLines = Get-Broken7zList 'C:\source.txt'
    if ($badLines.Count) {
        Write-Host "Found invalid lines:`n$($badLines -join "`n")" -ForegroundColor Red
    } else {
        Write-Host 'All paths are valid!' -ForegroundColor Green
    }
    #>
    
    [CmdletBinding()]
    param( 
        [Parameter(Mandatory, Position=0)] [string]$Path, 
        [switch]$ThrowOnError  
    )
    
    if (-not (Test-Path -LiteralPath $Path)) {
        throw "File '$Path' not found."
    }
    
    $broken     = @() # Array for invalid lines
    $seen       = New-Object System.Collections.Generic.HashSet[string] ([StringComparer]::OrdinalIgnoreCase) # HashSet for duplicates (case-insensitive)
    $badChars   = [System.IO.Path]::GetInvalidPathChars() # Invalid path characters
    $validCount = 0 # Counter for valid lines

    Get-Content -LiteralPath $Path | ForEach-Object {
        $raw  = $_
        $line = $raw.Trim()

        # Skip empty lines and comments
        if (-not $line -or $line.StartsWith('#')) { return }

        # Remove surrounding quotes (for paths with spaces in 7-Zip)
        if ($line.StartsWith('"') -and $line.EndsWith('"')) {
            $line = $line.Substring(1, $line.Length-2)
        }

        # Replace '/' with '\' for Test-Path
        $line = $line -replace '/', '\'

        if ($line.IndexOfAny($badChars) -ge 0) {
            $broken += "$raw   <-! contains invalid characters"; return
        }

        if ($line -notmatch '^[a-zA-Z]:\\|^\\\\') {
            $broken += "$raw   <-! not absolute path like X:\... or \\server\share"; return
        }

        if (-not (Test-Path -LiteralPath $line)) {
            $broken += "$raw   <-! object does not exist"; return
        }

        if (-not $seen.Add($line.ToLower())) {
            $broken += "$raw   <-! duplicate: appears multiple times"; return
        }
        $validCount++
    }
    
    if ($broken.Count -and $ThrowOnError) {
        throw "$(Get-Timestamp) The file `"source.txt`" contains invalid lines:`n$($broken -join "`n")"
    }

    if ($validCount -eq 0) {
        throw "File '$Path' contains no valid lines."
    }

    return ,$broken  # Comma ensures array return
}

function Start-BackUp {
    $run = $force -or (
        [System.Windows.Forms.MessageBox]::Show(
            "Need to make a backup. Click 'Ok' when you are ready.",
            $scriptName,
            [System.Windows.Forms.MessageBoxButtons]::OKCancel,
            [System.Windows.Forms.MessageBoxIcon]::Information
        ) -eq [System.Windows.Forms.DialogResult]::OK
    )

    if($run){
        # Checking for the presence of necessary files
        $files = @($7z, $sourceList, $excludeList, (Join-Path -Path $path -ChildPath "7z.dll"))
        $missing = $files | Where-Object { -not (Test-Path $_) }
        if ($missing) {
            Get-MsgBox "$(Get-Timestamp) Error! File(s) not found: $($missing -join ', ')."
            exit
        }
        
        # Checking source.txt
        try{
            Get-Broken7zList $sourceList -ThrowOnError
        } catch {
            Get-MsgBox $_
            exit
        }
        
        $check = $true
        $counter = 0
        while($check -and $counter -le 4) {
            # verification is necessary because of the -mhe key, otherwise the archive will be without a password but with encrypted headers.
            if(-not $pswd) {
                Write-Host "`n$(Get-Timestamp) Create a backup without a password" -ForegroundColor Magenta
                & $7z a -t7z (Join-Path -Path $target -ChildPath $filename) -bt -mx5 -ssw -snh -snl -ssp -spf2 @$sourceList -xr@"$excludeList" -scrcSHA256
            } else {
                Write-Host "`n$(Get-Timestamp) Create a backup with a password" -ForegroundColor DarkGreen
                & $7z a -t7z (Join-Path -Path $target -ChildPath $filename) -bt -mx5 -ssw -snh -snl -ssp -spf2 -p"$pswd" -mhe @$sourceList -xr@"$excludeList" -scrcSHA256
            }
    
            # check archive and data integrity
            Write-Host "`nCheck archive and data integrity. Wait..." -ForegroundColor Blue
            $result = & $7z t (Join-Path -Path $target -ChildPath $filename) -p"$pswd"
            if ($result -like "*Everything is Ok*") {
                foreach ($line in $result) {
                     Write-Host $line -ForegroundColor DarkYellow
                }
                Write-Host "`n$(Get-Timestamp) backup successfully created! `nFile name: $filename  `nPath: $target " -ForegroundColor Green
                Write-Host "This window will close in $waitTimeInSeconds seconds..."
                Start-Sleep -Seconds $waitTimeInSeconds
                $check = $false
            } else {
                Write-Host "`n$(Get-Timestamp) ERROR:" -ForegroundColor Red
                foreach ($line in $result) {
                     Write-Host $line -ForegroundColor Red
                }
            }
    
            $counter += 1
    
            # if the archive could not be created in 5 attempts, the cycle ends
            if ($counter -gt 4) {
                Get-MsgBox "$(Get-Timestamp) Failed to create archive after $counter attempts. Operation cancelled."
                $check = $false
            }
        }
    } else {
        Write-Host "`n$(Get-Timestamp)Backup creation cancelled." -ForegroundColor Red
        Write-Host "This window will close in $waitTimeInSeconds seconds..."
        Start-Sleep -Seconds $waitTimeInSeconds
    }
}

##################################### Run #####################################
Start-BackUp

if($logEnabled){ Stop-Transcript }