Elizium.Krayola

0.0.2

Public/Get-KrayolaTheme.ps1


function Get-KrayolaTheme {
  <#
    .NAME
      Get-KrayolaTheme
 
    .SYNOPSIS
      Helper function that makes it easier for client applications to get a Krayola theme
    from the environment, which is compatible with the terminal colours being used.
    This helps keep output from different applications consistent.
 
    .DESCRIPTION
      If $KrayolaThemeName is specified, then it is used to lookup the theme in the global
    $KrayolaThemes hashtable exposed by the Krayola module. If either the theme specified
    does not exist or not specified, then a default theme is used. The default theme created
    should be compatible with the dark/lightness of the background of the terminal currently
    in use. By default, a dark terminal is assumed and the colours used show up clearly
    against a dark background. If KRAYOLA-LIGHT-TERMINAL is defined as an environment
    variable (can be set to any string apart from empty string/white space), then the colours
    chosen show up best against a light background.
  #>
  [Diagnostics.CodeAnalysis.SuppressMessageAttribute('PSUseBOMForUnicodeEncodedFile', '')]
  [OutputType([System.Collections.Hashtable])]
  param (
    [Parameter(
      Mandatory = $false,
      Position = 0
    )]
    [AllowEmptyString()]
    [string]$KrayolaThemeName
  )

  # Theme is compatible with dark consoles by default
  #
  [System.Collections.Hashtable]$displayTheme = @{
    'FORMAT'             = '"<%KEY%>" => "<%VALUE%>"';
    'KEY-PLACE-HOLDER'   = '<%KEY%>';
    'VALUE-PLACE-HOLDER' = '<%VALUE%>';
    'KEY-COLOURS'        = @('DarkCyan');
    'VALUE-COLOURS'      = @('White');
    'OPEN'               = '[';
    'CLOSE'              = ']';
    'SEPARATOR'          = ', ';
    'META-COLOURS'       = @('Yellow');
    'MESSAGE-COLOURS'    = @('Cyan');
    'MESSAGE-SUFFIX'     = ' // ';
  }

  # Switch to use colours compatible with light consoles if KRAYOLA-LIGHT-TERMINAL
  # is set.
  #
  if (Get-IsKrayolaLightTerminal) {
    $displayTheme['KEY-COLOURS'] = 'DarkBlue';
    $displayTheme['VALUE-COLOURS'] = 'Red';
    $displayTheme['META-COLOURS'] = 'DarkMagenta';
    $displayTheme['MESSAGE-COLOURS'] = 'Green';
  }

  [string]$themeName = $KrayolaThemeName;

  # Get the theme name
  #
  if ([string]::IsNullOrWhiteSpace($themeName)) {
    $themeName = [System.Environment]::GetEnvironmentVariable('KRAYOLA-THEME-NAME');
  }

  if ($KrayolaThemes -and $KrayolaThemes.ContainsKey($themeName)) {
    $displayTheme = $KrayolaThemes[$themeName];
  }

  return $displayTheme;
}