Install-ConEmuTheme.ps1

[CmdletBinding()]

param (
    [Parameter(Position = 0, Mandatory = $false)]
    [ValidateNotNullOrEmpty()]
    [ValidateScript({Test-Path -Path $_})]
    [string]
    $ConfigPath = $env:APPDATA + "\ConEmu.xml",

    [Parameter(Position = 1, Mandatory = $true)]
    [ValidateSet("Add", "Remove")]
    [string]
    $Operation = "Add",

    [Parameter(Position = 2, Mandatory = $true)]
    [ValidateNotNullOrEmpty()]
    [ValidateScript({($Operation -eq "Remove") -or (Test-Path -Path $_)})]
    [string]
    $ThemePathOrName
)

function AddTheme {
    Param ([Xml]$Config, [string]$ThemeFile)

    $vanilla = $Config.key.key.key | Where-Object { $_.name -eq ".Vanilla" }
    $colors = $vanilla.key | Where-Object { $_.name -eq "Colors" }

    [Xml]$theme = Get-Content -Path $ThemeFile

    if ($colors -eq $null) {
        [Xml]$emptyColors = "<key name='Colors'><value name='Count' type='long' data='0'/></key>"
        $vanilla.AppendChild($config.ImportNode($emptyColors.DocumentElement, $true)) | Out-Null
        $colors = $vanilla.key | Where-Object { $_.name -eq "Colors" }
    } else {
        $themeName = ($theme.key.value | Where-Object { $_.name -eq "Name" }).data
        $existingTheme = $colors.key | Where-Object { $_.value | Where-Object { $_.name -eq "Name" -and $_.data -eq $themeName } }
        if ($existingTheme -ne $null) {
            throw "Theme was already added to config"
        }
    }
    $colors.AppendChild($config.ImportNode($theme.DocumentElement, $true)) | Out-Null
    return $colors
}

function RemoveTheme {
    Param ([Xml]$Config, [string]$ThemeToRemove)

    $vanilla = $Config.key.key.key | Where-Object { $_.name -eq ".Vanilla" }
    $colors = $vanilla.key | Where-Object { $_.name -eq "Colors" }
    $theme = $colors.key | Where-Object { $_.value | Where-Object { $_.name -eq "Name" -and $_.data -eq $ThemeToRemove} }
    if ($theme -eq $null) {
        throw "Theme $ThemeToRemove not found in config"
    }
    $colors.RemoveChild($theme) | Out-Null
    return $colors
}

try {
    [Xml]$config = Get-Content -Path $ConfigPath
    $config.Save([System.IO.Path]::ChangeExtension($ConfigPath, ".backup.xml"))

    $vanilla = $config.key.key.key | Where-Object { $_.name -eq ".Vanilla" }
    $colors = $vanilla.key | Where-Object { $_.name -eq "Colors" }

    switch ($Operation) {
        "Add" {
            # If $ThemePathOrName is a file, then add the theme file
            if (Test-Path $ThemePathOrName -pathType leaf) {
                $colors = AddTheme -Config $config -ThemeFile $ThemePathOrName
            }
            # If it is a folder, then attempt to add all children of that folder
            if (Test-Path $ThemePathOrName -pathType container) {
                $themeFiles = Get-ChildItem $ThemePathOrName
                foreach ($themeFile in $themeFiles) {
                    try {
                        $colors = AddTheme -Config $config -ThemeFile $ThemePathOrName\$themeFile
                    } catch {
                        Write-Host Skipped: $themeFile
                    }
                }
            }
        }
        "Remove" {
            if ($colors -eq $null -or $colors.key -eq $null) {
                throw "No themes in config"
            }
            if (Test-Path $ThemePathOrName -pathType leaf) {
                [Xml]$themeFileContents = Get-Content -Path $ThemePathOrName
                $themeName = ($themeFileContents.key.value | Where-Object { $_.name -eq "Name" }).data
            } else {
                $themeName = $ThemePathOrName
            }
            $colors = RemoveTheme -Config $config -ThemeToRemove $themeName
        }
    }

    if ($colors.key -eq $null) {
        $colors.value.data = "0"
    } elseif ($colors.key -is [System.Array]) {
        $colors.value.data = $colors.key.Count.ToString()
        for ($i = 0; $i -lt $colors.key.Count; $i++) {
            $colors.key[$i].name = "Palette$($i + 1)"
        }
    } else {
        $colors.value.data = "1"
        $colors.key.name = "Palette1"
    }

    $config.Save($ConfigPath)
} catch {
    Write-Error -Message $_
}