<#
.SYNOPSIS
Minimal hosted PowerShell starter for Windows.

.DESCRIPTION
Replace the placeholder command body in Invoke-RunCli with your project behavior.

.EXAMPLE
./script.ps1 -Help

.EXAMPLE
./script.ps1 -Version

.EXAMPLE
$env:DEBUG = '1'
./script.ps1

Run `./script.ps1 -Help` for more advanced usage.
#>
[CmdletBinding()]
param(
  [switch]$Help,
  [switch]$Version,

  [Parameter(ValueFromRemainingArguments = $true)]
  [string[]]$Positionals
)

Set-StrictMode -Version 3
$ErrorActionPreference = 'Stop'

$CLI_NAME = if (
  -not [string]::IsNullOrWhiteSpace($MyInvocation.InvocationName) -and
  $MyInvocation.InvocationName -notin @('.', '&') -and
  $MyInvocation.InvocationName -notmatch '^(?:pwsh|powershell)(?:\.exe)?$'
) {
  Split-Path -Leaf $MyInvocation.InvocationName
} elseif ($PSCommandPath) {
  Split-Path -Leaf $PSCommandPath
} elseif ($MyInvocation.MyCommand.Name) {
  $MyInvocation.MyCommand.Name
} else {
  'script.ps1'
}
# Keep a single top-level assignment so release automation can stamp the entrypoint in place.
$SCRIPT_VERSION = "v1.0.0-beta.2"
$ESCAPE = [char]27
$USE_COLOR = $false
$script:DebugEnabled = $false

function Test-Truthy {
  param([AllowNull()][object]$Value)

  $normalized = ''
  if (-not [string]::IsNullOrWhiteSpace([string]$Value)) {
    $normalized = ([string]$Value).Trim().ToLowerInvariant()
  }

  switch ($normalized) {
    '' { return $false }
    '0' { return $false }
    'false' { return $false }
    'no' { return $false }
    'off' { return $false }
    default { return $true }
  }
}

# Normalize debug preference using the common -Debug parameter plus env fallbacks.
$DebugPreference = if (
  $PSBoundParameters.ContainsKey('Debug') -or
  (Test-Truthy $env:DEBUG) -or
  (Test-Truthy $env:RUNNER_DEBUG)
) {
  'Continue'
} else {
  $DebugPreference
}

if ($DebugPreference -eq 'Inquire' -or $DebugPreference -eq 'Continue') {
  $script:DebugEnabled = $true
}

function Test-ColorEnabled {
  if (-not [string]::IsNullOrWhiteSpace($env:NO_COLOR)) {
    return $false
  }

  if (Test-Truthy $env:FORCE_COLOR) {
    return $true
  }

  if (
    $env:OS -eq 'Windows_NT' -and
    $PSVersionTable.PSVersion.Major -lt 7 -and
    [string]::IsNullOrWhiteSpace($env:WT_SESSION) -and
    [string]::IsNullOrWhiteSpace($env:TERM)
  ) {
    return $false
  }

  try {
    return (-not [Console]::IsOutputRedirected) -or (-not [Console]::IsErrorRedirected)
  } catch {
    return $true
  }
}

function Format-Style {
  param(
    [string]$Code,
    [string]$Text
  )

  if (-not $script:USE_COLOR) {
    return $Text
  }

  return '{0}[{1}m{2}{0}[0m' -f $script:ESCAPE, $Code, $Text
}

function bold {
  param([string]$Text)
  return Format-Style -Code '1;39' -Text $Text
}

function dim {
  param([string]$Text)
  return Format-Style -Code '2;39' -Text $Text
}

function red {
  param([string]$Text)
  return Format-Style -Code '1;31' -Text $Text
}

function tp {
  param([string]$Text)
  return Format-Style -Code '38;2;0;200;138' -Text $Text
}

function ts {
  param([string]$Text)
  return Format-Style -Code '38;2;219;39;119' -Text $Text
}

function Expand-Message {
  param(
    [AllowNull()][object]$Message,
    [object[]]$MessageArgs = @()
  )

  $normalized = if ($Message -is [string]) {
    $Message
  } else {
    ($Message | Out-String).TrimEnd()
  }

  if ($MessageArgs.Count -gt 0) {
    return $normalized -f $MessageArgs
  }

  return $normalized
}

function Write-Status {
  param(
    [string]$Label,
    [scriptblock]$Colorizer,
    [AllowNull()][object]$Message = '',
    [object[]]$MessageArgs = @()
  )

  $text = Expand-Message -Message $Message -MessageArgs $MessageArgs
  Write-Information ('{0}: {1}' -f (& $Colorizer $Label), $text) -InformationAction Continue
}

function debug {
  param(
    [AllowNull()][object]$Message = '',
    [object[]]$MessageArgs = @()
  )

  if (-not $script:DebugEnabled) {
    return
  }

  Write-Debug (Expand-Message -Message $Message -MessageArgs $MessageArgs)
}

function log {
  param(
    [AllowNull()][object]$Message = '',
    [object[]]$MessageArgs = @()
  )

  Write-Output (Expand-Message -Message $Message -MessageArgs $MessageArgs)
}

function note {
  param(
    [AllowNull()][object]$Message = '',
    [object[]]$MessageArgs = @()
  )

  Write-Status -Label 'note' -Colorizer ${function:ts} -Message $Message -MessageArgs $MessageArgs
}

function fail {
  param(
    [string]$Message
  )

  $text = Expand-Message -Message $Message
  Write-Error -Message ('error: {0}' -f $text) -ErrorAction Stop
}

function Show-Version {
  Write-Output $script:SCRIPT_VERSION
}

function Show-Usage {
  param(
    [Parameter(Mandatory)]
    [bool]$DebugEnabled
  )

  $debugDisplay = if ($DebugEnabled) { 'on' } else { 'off' }
  $lines = @(
    ('Usage: {0} {1}' -f (bold $script:CLI_NAME), (dim '[-Debug] [-Version] [-Help] [arguments...]'))
    ''
    ('{0}:' -f (tp 'Options'))
    ('  -Debug    enable debug logging {0}' -f (dim ('[default: {0}]' -f $debugDisplay)))
    ('  -Version  print the script version {0}' -f (dim ('[default: {0}]' -f $script:SCRIPT_VERSION)))
    '  -Help     show this help message'
    ''
    'This starter intentionally has no product logic yet.'
    'Additional arguments are ignored by the starter until you replace the placeholder logic.'
    ('Replace the body of {0} with your project behavior.' -f $script:CLI_NAME)
  )

  Write-Output ($lines -join [Environment]::NewLine)
}

function Invoke-RunCli {
  if ($script:Resolved.Positionals.Count -gt 0) {
    debug 'ignoring starter positional arguments: {0}' ($script:Resolved.Positionals -join ' ')
  }

  debug 'running placeholder command body'
  log 'Replace the body of {0} with your project logic.' $script:CLI_NAME
}

$script:USE_COLOR = Test-ColorEnabled

$script:Resolved = [pscustomobject]@{
  Debug = $script:DebugEnabled
  Positionals = @($Positionals)
}

if ($Help) {
  Show-Usage -DebugEnabled $script:Resolved.Debug
  return
}

if ($Version) {
  Show-Version
  return
}

Invoke-RunCli