param([string]$AssemblyPath = (Join-Path $PSScriptRoot '..\bin\Debug\netstandard2.0\ClumsyPilot.dll'))

$ErrorActionPreference = 'Stop'
$assembly = [Reflection.Assembly]::LoadFrom((Resolve-Path $AssemblyPath))

function Assert-True($Actual, [string]$Message) {
    if (-not $Actual) { throw $Message }
}

function Assert-False($Actual, [string]$Message) {
    if ($Actual) { throw $Message }
}

function Assert-Equal($Expected, $Actual, [string]$Message) {
    if ($Expected -ne $Actual) { throw "$Message Expected=$Expected Actual=$Actual" }
}

function Assert-Near([double]$Expected, [double]$Actual, [string]$Message) {
    if ([Math]::Abs($Expected - $Actual) -gt 0.000000001) {
        throw "$Message Expected=$Expected Actual=$Actual"
    }
}

function Get-RequiredType([string]$Name) {
    return $assembly.GetType($Name, $true)
}

function Assert-AttemptedStrengths($Snapshot, [double[]]$Expected, [string]$Message) {
    Assert-Equal $Expected.Length $Snapshot.AttemptedStrengths.Count ($Message + ' count')
    for ($index = 0; $index -lt $Expected.Length; $index++) {
        Assert-Near $Expected[$index] $Snapshot.AttemptedStrengths[$index] ($Message + " index=$index")
    }
}

$root = 'MultiWheelC.TrajectoryPlanning.PathSmoothing.'
$algorithms = $root + 'Algorithms.'
$runnerType = Get-RequiredType ($algorithms + 'SmoothingAlgorithmRunner')
$smootherType = Get-RequiredType ($algorithms + 'IPathSmoother')
$candidateType = Get-RequiredType ($algorithms + 'SmoothingCandidate')
$candidateStatusType = Get-RequiredType ($algorithms + 'SmoothingCandidateStatus')
Assert-False $smootherType.IsPublic 'IPathSmoother must remain internal to the algorithm assembly.'
Assert-Equal 3 ([Enum]::GetNames($candidateStatusType).Length) 'Smoothing candidate status must contain only the three defined feasibility states.'
Assert-Equal 'Success' ([Enum]::GetNames($candidateStatusType)[0]) 'Candidate status must expose Success.'
Assert-Equal 'RetryableInfeasible' ([Enum]::GetNames($candidateStatusType)[1]) 'Candidate status must expose RetryableInfeasible.'
Assert-Equal 'Failed' ([Enum]::GetNames($candidateStatusType)[2]) 'Candidate status must expose Failed.'
$retryableFactory = $candidateType.GetMethod('RetryableInfeasible', [Reflection.BindingFlags]'Static,NonPublic')
Assert-True ($null -ne $retryableFactory) 'SmoothingCandidate must create retryable infeasibility without executable geometry.'

$hooksType = $runnerType.GetNestedType('TestHooks', [Reflection.BindingFlags]'Public,NonPublic')
Assert-True ($null -ne $hooksType) 'SmoothingAlgorithmRunner must expose its narrowly scoped nested TestHooks helper.'
$executeMethod = $hooksType.GetMethod('Execute', [Reflection.BindingFlags]'Public,Static')
Assert-True ($null -ne $executeMethod) 'TestHooks must expose deterministic scenario execution for reflection tests.'

function Invoke-Scenario([string]$Scenario) {
    return $executeMethod.Invoke($null, @($Scenario))
}

$allRetryable = Invoke-Scenario 'RetryableInfeasible'
Assert-Equal 'Infeasible' $allRetryable.Status 'Exhausted retryable infeasibility must produce an Infeasible runner result.'
Assert-AttemptedStrengths $allRetryable @(1.00, 0.75, 0.50, 0.25) 'Retryable infeasibility must use the finite retry schedule exactly.'
Assert-Equal 0 $allRetryable.AcceptedPathPointCount 'An infeasible runner result must not retain a retryable candidate as an accepted path.'
Assert-Equal 0 $allRetryable.RejectedComparisonCandidatePointCount 'Retryable infeasibility must not retain executable candidate geometry.'
Assert-Equal 4 $allRetryable.FailureCount 'Every retryable attempt must retain its failure reason.'

$accepted = Invoke-Scenario 'AcceptFirst'
Assert-Equal 'Success' $accepted.Status 'The first safe candidate must be accepted.'
Assert-AttemptedStrengths $accepted @(1.00) 'The runner must stop immediately after the first accepted candidate.'
Assert-True ($accepted.AcceptedPathPointCount -gt 0) 'A successful runner result must publish the validated path internally.'
Assert-Equal 0 $accepted.RejectedComparisonCandidatePointCount 'An accepted candidate must not create rejected comparison geometry.'

$terminalFailure = Invoke-Scenario 'TerminalFailed'
Assert-Equal 'Failed' $terminalFailure.Status 'A terminal candidate failure must stop the runner as Failed.'
Assert-AttemptedStrengths $terminalFailure @(1.00) 'Terminal candidate failure must run exactly once.'
Assert-Equal 0 $terminalFailure.RejectedComparisonCandidatePointCount 'A terminal failure must not retain comparison geometry.'

$cancelled = Invoke-Scenario 'CancelBeforeNextAttempt'
Assert-True $cancelled.CancellationPropagated 'Cancellation between attempts must propagate out of the runner.'
Assert-AttemptedStrengths $cancelled @(1.00) 'Cancellation before the next attempt must prevent another smoother call.'
Assert-Equal 0 $cancelled.AcceptedPathPointCount 'A cancelled run must not publish a partial path.'

Write-Output 'Path smoothing retry runner checks passed.'