feat: add color blind accessibility command suite

.github/workflows/CI.yaml

@@ -5,6 +5,9 @@ on:
 permissions:
   checks: write
   pull-requests: write
+  contents: read
+  issues: write
 jobs:
   ci:
+    name: Continuous Integration
     uses: PSInclusive/.github/.github/workflows/ModuleCI.yml@main

Accessibility/Private/Get-ColorBlindPaletteData.ps1

@@ -0,0 +1,105 @@
+# Okabe-Ito palette: peer-reviewed, safe across all common colorblindness types.
+# Source: https://jfly.uni-koeln.de/color/
+$script:OKABE_ITO = @{
+    Black         = @{ R = 0;   G = 0;   B = 0   }
+    Orange        = @{ R = 230; G = 159; B = 0   }
+    SkyBlue       = @{ R = 86;  G = 180; B = 233 }
+    BluishGreen   = @{ R = 0;   G = 158; B = 115 }
+    Yellow        = @{ R = 240; G = 228; B = 66  }
+    Blue          = @{ R = 0;   G = 114; B = 178 }
+    Vermillion    = @{ R = 213; G = 94;  B = 0   }
+    ReddishPurple = @{ R = 204; G = 121; B = 167 }
+}
+
+function Get-ColorBlindPaletteData {
+    <#
+    .SYNOPSIS
+    Returns the RGB color table for a named color blind profile.
+
+    .DESCRIPTION
+    Returns a hashtable of named color entries (each with R, G, B keys) for the specified
+    color blindness profile. All profiles are derived from the Okabe-Ito palette, adjusted
+    per the specific perceptual needs of each condition.
+
+    .PARAMETER ProfileType
+    The color blindness profile to retrieve. Valid values: Deuteranopia, Protanopia,
+    Tritanopia, Achromatopsia, AccessibleDefault.
+
+    .EXAMPLE
+    Get-ColorBlindPaletteData -ProfileType Deuteranopia
+    #>
+    param (
+        [Parameter(Mandatory = $true)]
+        [ValidateSet('Deuteranopia', 'Protanopia', 'Tritanopia', 'Achromatopsia', 'AccessibleDefault')]
+        [string]$ProfileType
+    )
+
+    switch ($ProfileType) {
+        'Deuteranopia' {
+            # Red-green deficiency (most common). Maximize blue/orange/yellow contrast.
+            # Red and green are shifted to orange and blue respectively.
+            @{
+                Error     = $script:OKABE_ITO.Vermillion     # Vermillion (not red)
+                Warning   = $script:OKABE_ITO.Orange         # Orange
+                Success   = $script:OKABE_ITO.Blue           # Blue (not green)
+                Info      = $script:OKABE_ITO.SkyBlue        # Sky Blue
+                Highlight = $script:OKABE_ITO.Yellow         # Yellow
+                Accent    = $script:OKABE_ITO.ReddishPurple  # Reddish Purple
+                Text      = $script:OKABE_ITO.Black          # Black
+                Muted     = @{ R = 120; G = 120; B = 120 }   # Mid-gray (not part of Okabe-Ito)
+            }
+        }
+        'Protanopia' {
+            # Red-weak (cannot perceive red). Red-range hues shifted further toward orange/yellow.
+            @{
+                Error     = @{ R = 230; G = 159; B = 0   }  # Orange (red is invisible)
+                Warning   = @{ R = 240; G = 228; B = 66  }  # Yellow
+                Success   = @{ R = 0;   G = 114; B = 178 }  # Blue
+                Info      = @{ R = 86;  G = 180; B = 233 }  # Sky Blue
+                Highlight = @{ R = 204; G = 121; B = 167 }  # Reddish Purple
+                Accent    = @{ R = 0;   G = 158; B = 115 }  # Bluish Green
+                Text      = @{ R = 0;   G = 0;   B = 0   }  # Black
+                Muted     = @{ R = 120; G = 120; B = 120 }  # Mid-gray
+            }
+        }
+        'Tritanopia' {
+            # Blue-yellow deficiency. Shift to red/green contrast; replace blue with high-contrast cyan.
+            @{
+                Error     = @{ R = 213; G = 94;  B = 0   }  # Vermillion
+                Warning   = @{ R = 204; G = 121; B = 167 }  # Reddish Purple (not yellow)
+                Success   = @{ R = 0;   G = 158; B = 115 }  # Bluish Green
+                Info      = @{ R = 0;   G = 200; B = 200 }  # Cyan (high contrast, not pure blue)
+                Highlight = @{ R = 255; G = 100; B = 100 }  # Light Red (visible to tritanopes)
+                Accent    = @{ R = 180; G = 60;  B = 60  }  # Dark Red
+                Text      = @{ R = 0;   G = 0;   B = 0   }  # Black
+                Muted     = @{ R = 120; G = 120; B = 120 }  # Mid-gray
+            }
+        }
+        'Achromatopsia' {
+            # Full colorblindness. High-contrast grayscale ladder designed for strong separation between steps.
+            @{
+                Error     = @{ R = 30;  G = 30;  B = 30  }  # Near-black (on white bg)
+                Warning   = @{ R = 80;  G = 80;  B = 80  }  # Dark gray
+                Success   = @{ R = 50;  G = 50;  B = 50  }  # Dark gray variant
+                Info      = @{ R = 110; G = 110; B = 110 }  # Medium gray
+                Highlight = @{ R = 230; G = 230; B = 230 }  # Near-white
+                Accent    = @{ R = 0;   G = 0;   B = 0   }  # Black
+                Text      = @{ R = 0;   G = 0;   B = 0   }  # Black
+                Muted     = @{ R = 160; G = 160; B = 160 }  # Light gray
+            }
+        }
+        'AccessibleDefault' {
+            # Okabe-Ito as-is: a safe general baseline for users unsure of their type.
+            @{
+                Error     = @{ R = 213; G = 94;  B = 0   }  # Vermillion
+                Warning   = @{ R = 230; G = 159; B = 0   }  # Orange
+                Success   = @{ R = 0;   G = 158; B = 115 }  # Bluish Green
+                Info      = @{ R = 86;  G = 180; B = 233 }  # Sky Blue
+                Highlight = @{ R = 240; G = 228; B = 66  }  # Yellow
+                Accent    = @{ R = 0;   G = 114; B = 178 }  # Blue
+                Text      = @{ R = 0;   G = 0;   B = 0   }  # Black
+                Muted     = @{ R = 120; G = 120; B = 120 }  # Mid-gray
+            }
+        }
+    }
+}

Accessibility/Private/Get-ContrastRatio.ps1

@@ -0,0 +1,34 @@
+function Get-ContrastRatio {
+    <#
+    .SYNOPSIS
+    Calculates the WCAG contrast ratio between two relative luminance values.
+
+    .DESCRIPTION
+    Implements the W3C WCAG 2.1 contrast ratio formula. Returns a ratio between 1:1
+    (no contrast) and 21:1 (maximum contrast, black on white).
+
+    .PARAMETER Luminance1
+    Relative luminance of the first color (0.0 to 1.0).
+
+    .PARAMETER Luminance2
+    Relative luminance of the second color (0.0 to 1.0).
+
+    .EXAMPLE
+    Get-ContrastRatio -Luminance1 1.0 -Luminance2 0.0
+    # Returns 21.0 (white on black)
+
+    .NOTES
+    https://www.w3.org/TR/WCAG21/#dfn-contrast-ratio
+    #>
+    param (
+        [Parameter(Mandatory = $true)]
+        [double]$Luminance1,
+        [Parameter(Mandatory = $true)]
+        [double]$Luminance2
+    )
+
+    $lighter = [Math]::Max($Luminance1, $Luminance2)
+    $darker  = [Math]::Min($Luminance1, $Luminance2)
+
+    return ($lighter + 0.05) / ($darker + 0.05)
+}

Accessibility/Private/Get-RelativeLuminance.ps1

@@ -0,0 +1,52 @@
+function Get-RelativeLuminance {
+    <#
+    .SYNOPSIS
+    Calculates the relative luminance of an RGB color per the W3C WCAG 2.1 formula.
+
+    .DESCRIPTION
+    Implements the W3C relative luminance formula required for WCAG contrast ratio
+    calculations. Returns a value between 0 (black) and 1 (white).
+
+    .PARAMETER R
+    Red channel value (0-255).
+
+    .PARAMETER G
+    Green channel value (0-255).
+
+    .PARAMETER B
+    Blue channel value (0-255).
+
+    .EXAMPLE
+    Get-RelativeLuminance -R 0 -G 0 -B 0
+    # Returns 0 (black)
+
+    .EXAMPLE
+    Get-RelativeLuminance -R 255 -G 255 -B 255
+    # Returns 1 (white)
+
+    .NOTES
+    https://www.w3.org/TR/WCAG21/#dfn-relative-luminance
+    #>
+    param (
+        [Parameter(Mandatory = $true)]
+        [ValidateRange(0, 255)]
+        [int]$R,
+        [Parameter(Mandatory = $true)]
+        [ValidateRange(0, 255)]
+        [int]$G,
+        [Parameter(Mandatory = $true)]
+        [ValidateRange(0, 255)]
+        [int]$B
+    )
+
+    $channels = @($R / 255.0, $G / 255.0, $B / 255.0)
+    $linearized = $channels | ForEach-Object {
+        if ($_ -le 0.04045) {
+            $_ / 12.92
+        } else {
+            [Math]::Pow(($_ + 0.055) / 1.055, 2.4)
+        }
+    }
+
+    return (0.2126 * $linearized[0]) + (0.7152 * $linearized[1]) + (0.0722 * $linearized[2])
+}

Accessibility/Public/ConvertTo-PlainText.ps1

@@ -0,0 +1,51 @@
+function ConvertTo-PlainText {
+    <#
+    .SYNOPSIS
+    Strips common ANSI color/style escape codes and PSStyle formatting from a string.
+
+    .DESCRIPTION
+    Removes common ANSI/VT100 SGR-style escape sequences (colors, bold, italic, etc.)
+    from text, returning clean plain text without those decorations. Useful for
+    preparing terminal output for screen readers, plain-text logging, or piping to
+    tools that do not handle such escape codes.
+
+    Supports pipeline input.
+
+    .PARAMETER InputText
+    The text string to strip of ANSI color/style escape codes.
+
+    .EXAMPLE
+    ConvertTo-PlainText -InputText "$($PSStyle.Bold)Hello$($PSStyle.BoldOff) World"
+
+    Returns 'Hello World' with no formatting.
+
+    .EXAMPLE
+    ConvertTo-Bionic "The quick brown fox" | ConvertTo-PlainText
+
+    Converts text to bionic format then strips common ANSI color/style escape sequences
+    for screen reader use.
+
+    .EXAMPLE
+    Get-Content .\log.txt -Raw | ConvertTo-PlainText
+
+    Strips common ANSI color/style escape codes from a log file that may contain
+    colored output.
+
+    .NOTES
+    https://www.w3.org/WAI/WCAG21/Techniques/general/G166
+    #>
+    [CmdletBinding()]
+    param (
+        [Parameter(
+            Mandatory = $true,
+            ValueFromPipeline = $true,
+            Position = 0
+        )]
+        [string]$InputText
+    )
+
+    process {
+        # Matches ESC (0x1B) followed by [ and any sequence of parameter/intermediate bytes and a final byte
+        $InputText -replace '\x1B\[[0-9;]*[mABCDEFGHJKSTfhilmnprsu]', ''
+    }
+}

Accessibility/Public/Disable-ScreenReaderMode.ps1

@@ -0,0 +1,40 @@
+function Disable-ScreenReaderMode {
+    <#
+    .SYNOPSIS
+    Restores normal ANSI-formatted terminal output after screen reader mode.
+
+    .DESCRIPTION
+    Clears the screen reader mode flag set by Enable-ScreenReaderMode, allowing
+    Accessibility module commands to resume producing colored and styled terminal
+    output using ANSI escape sequences.
+
+    .EXAMPLE
+    Disable-ScreenReaderMode
+
+    Deactivates screen reader mode and restores ANSI-formatted output.
+
+    .EXAMPLE
+    Enable-ScreenReaderMode
+    ConvertTo-Bionic "Example text"
+    Disable-ScreenReaderMode
+
+    Temporarily uses screen reader mode for one operation, then restores normal output.
+
+    .NOTES
+    https://www.w3.org/WAI/WCAG21/Understanding/non-text-contrast
+    #>
+    [CmdletBinding()]
+    param ()
+
+    $script:ScreenReaderMode = $false
+
+    if ($script:PreviousOutputRendering) {
+        $PSStyle.OutputRendering = $script:PreviousOutputRendering
+        Write-Verbose "Screen reader mode disabled. Previous output rendering restored."
+    }
+    else {
+        # Fallback if no previous output rendering mode was saved.
+        $PSStyle.OutputRendering = [System.Management.Automation.OutputRendering]::Host
+        Write-Verbose "Screen reader mode disabled. Output rendering set to Host."
+    }
+}

Accessibility/Public/Enable-ScreenReaderMode.ps1

@@ -0,0 +1,40 @@
+function Enable-ScreenReaderMode {
+    <#
+    .SYNOPSIS
+    Optimizes terminal output for screen reader assistive technology.
+
+    .DESCRIPTION
+    Sets a module-wide flag that signals all Accessibility module commands to produce
+    output that is compatible with screen readers: no ANSI color codes, no box-drawing
+    characters, simplified structure, and plain descriptive text only.
+
+    Use Disable-ScreenReaderMode to return to normal output mode.
+
+    .EXAMPLE
+    Enable-ScreenReaderMode
+
+    Activates screen reader-friendly output mode for all Accessibility module commands.
+
+    .EXAMPLE
+    Enable-ScreenReaderMode
+    ConvertTo-Bionic "The quick brown fox jumped over the lazy dog."
+
+    Enables screen reader mode then runs a bionic conversion. Output will contain no
+    ANSI bold codes, just the plain text result.
+
+    .NOTES
+    https://www.w3.org/WAI/WCAG21/Understanding/non-text-contrast
+    #>
+    [CmdletBinding()]
+    param ()
+
+    $script:ScreenReaderMode = $true
+
+    if (-not (Get-Variable -Name PreviousOutputRendering -Scope Script -ErrorAction SilentlyContinue)) {
+        $script:PreviousOutputRendering = $PSStyle.OutputRendering
+    }
+
+    $PSStyle.OutputRendering = [System.Management.Automation.OutputRendering]::PlainText
+
+    Write-Verbose "Screen reader mode enabled. ANSI output suppressed."
+}

Accessibility/Public/Export-AccessibilityProfile.ps1

@@ -0,0 +1,41 @@
+function Export-AccessibilityProfile {
+    <#
+    .SYNOPSIS
+    Exports the current accessibility settings to a JSON file.
+
+    .DESCRIPTION
+    Serializes all active accessibility settings (color blind profile, screen reader mode,
+    output rendering) to a JSON file at the specified path. The file can later be restored
+    using Import-AccessibilityProfile, making it easy to share configurations or persist
+    them outside of $PROFILE.
+
+    .PARAMETER Path
+    The file path where the JSON settings file should be written.
+
+    .EXAMPLE
+    Export-AccessibilityProfile -Path "$HOME\accessibility-settings.json"
+
+    Exports the current settings to a JSON file in the user's home directory.
+
+    .EXAMPLE
+    Set-ColorBlindProfile -ProfileType Deuteranopia
+    Export-AccessibilityProfile -Path ".\my-profile.json"
+
+    Applies a color profile then exports it to a local file.
+
+    .NOTES
+    https://www.w3.org/WAI/WCAG21/Understanding/
+    #>
+    [CmdletBinding(SupportsShouldProcess)]
+    param (
+        [Parameter(Mandatory = $true, Position = 0)]
+        [string]$Path
+    )
+
+    $profile = Get-AccessibilityProfile
+
+    if ($PSCmdlet.ShouldProcess($Path, "Export accessibility settings")) {
+        $profile | ConvertTo-Json -Depth 5 | Set-Content -Path $Path -Encoding UTF8
+        Write-Verbose "Accessibility settings exported to: $Path"
+    }
+}