<#
.SYNOPSIS
    BakNRet 测试用的极简断言运行器（零依赖，PS 5.1 / 7.x 通用）。

.DESCRIPTION
    不用 Pester：本机只装了 3.4.0，缺少 `Should -Be` 这类 Pester 4+ 语法，
    为跑几个测试去装 Pester 5 不划算。这里只需要 Test-Case + Assert-* 就够。
#>

$script:Passed = 0
$script:Failed = 0
$script:Failures = @()

function Reset-TestResult {
    $script:Passed = 0
    $script:Failed = 0
    $script:Failures = @()
}

function Get-TestResult {
    return [pscustomobject]@{
        Passed   = $script:Passed
        Failed   = $script:Failed
        Failures = @($script:Failures)
    }
}

function Test-Case {
    param([string]$Name, [scriptblock]$Body)

    try {
        & $Body
        $script:Passed++
        Write-Host "  [PASS] $Name" -ForegroundColor Green
    } catch {
        $script:Failed++
        $script:Failures += "$Name —— $($_.Exception.Message)"
        Write-Host "  [FAIL] $Name" -ForegroundColor Red
        Write-Host "         $($_.Exception.Message)" -ForegroundColor DarkGray
    }
}

function Assert-Equal {
    param($Expected, $Actual, [string]$Because)
    if ($Expected -ne $Actual) {
        throw ("期望 [{0}]，实际 [{1}]{2}" -f $Expected, $Actual, $(if ($Because) { "（$Because）" } else { '' }))
    }
}

function Assert-True {
    param($Condition, [string]$Because)
    if (-not $Condition) { throw ("断言为真失败{0}" -f $(if ($Because) { "：$Because" } else { '' })) }
}

function Assert-False {
    param($Condition, [string]$Because)
    if ($Condition) { throw ("断言为假失败{0}" -f $(if ($Because) { "：$Because" } else { '' })) }
}

function Assert-Null {
    param($Value, [string]$Because)
    if ($null -ne $Value) {
        throw ("期望为 null，实际 [{0}]{1}" -f $Value, $(if ($Because) { "（$Because）" } else { '' }))
    }
}

function Assert-FileExists {
    param([string]$Path, [string]$Because)
    if (-not (Test-Path -LiteralPath $Path)) {
        throw ("文件应当存在但不存在：{0}{1}" -f $Path, $(if ($Because) { "（$Because）" } else { '' }))
    }
}

function Assert-FileMissing {
    param([string]$Path, [string]$Because)
    if (Test-Path -LiteralPath $Path) {
        throw ("文件不应存在但存在：{0}{1}" -f $Path, $(if ($Because) { "（$Because）" } else { '' }))
    }
}

function Assert-FileHashEqual {
    param([string]$ExpectedPath, [string]$ActualPath)
    Assert-FileExists $ExpectedPath
    Assert-FileExists $ActualPath
    $a = (Get-FileHash -LiteralPath $ExpectedPath -Algorithm SHA256).Hash
    $b = (Get-FileHash -LiteralPath $ActualPath -Algorithm SHA256).Hash
    if ($a -ne $b) { throw ("内容不一致：{0} vs {1}" -f $ExpectedPath, $ActualPath) }
}

function Write-TestSummary {
    param([string]$Title = '测试')

    Write-Host ""
    Write-Host ("=" * 60)
    if ($script:Failed -eq 0) {
        Write-Host "$Title 全部通过：$($script:Passed) 项" -ForegroundColor Green
    } else {
        Write-Host "$Title 通过 $($script:Passed) 项，失败 $($script:Failed) 项" -ForegroundColor Red
        foreach ($failure in $script:Failures) { Write-Host "  - $failure" -ForegroundColor Red }
    }
    Write-Host ("=" * 60)

    return $script:Failed
}

Export-ModuleMember -Function @(
    'Reset-TestResult', 'Get-TestResult', 'Test-Case',
    'Assert-Equal', 'Assert-True', 'Assert-False', 'Assert-Null',
    'Assert-FileExists', 'Assert-FileMissing', 'Assert-FileHashEqual',
    'Write-TestSummary'
)