<#
.SYNOPSIS
  Tests statiques d'integrite T-STAT-02 a T-STAT-04 (Docs/Migration/03_Plan_Migration_Tests.md).

.DESCRIPTION
  -Modules : Content/Modules 5.5 identique a 4.27 (liste et MD5).
  -Env     : environnement de developpement identique au manifeste du lot L0.
  -Ref427  : arbre 4.27 inchange depuis l'empreinte de reference.
  -InitRef427 : cree l'empreinte de reference 4.27 (a faire une seule fois, en L0).
  Code de sortie 1 si un test echoue.

.EXAMPLE
  .\Tools\CheckIntegrity.ps1 -Modules -Env -Ref427
#>
param(
    [switch]$Modules,
    [switch]$Env,
    [switch]$Ref427,
    [switch]$InitRef427,
    [string]$ProjectRoot = (Split-Path $PSScriptRoot -Parent),
    [string]$Root427 = 'D:\Game\LifePlay-master 4.27',
    [string]$BackupRoot = 'D:\Game\LifePlay_Backup_5.5'
)
$ErrorActionPreference = 'Stop'
$refCsv = Join-Path $ProjectRoot 'Docs\Migration\etat\L0_ref427.csv'
$failed = 0

function Hash-Tree([string]$Base, [string[]]$Rel) {
    foreach ($r in $Rel) {
        $p = Join-Path $Base $r
        if (-not (Test-Path $p)) { continue }
        Get-ChildItem $p -File -Recurse -Force | ForEach-Object {
            [pscustomobject]@{ Rel = $_.FullName.Substring($Base.TrimEnd('\').Length + 1); MD5 = (Get-FileHash $_.FullName -Algorithm MD5).Hash }
        }
    }
}

function Report([string]$Name, [object[]]$Diffs, [int]$Total) {
    if ($Diffs) {
        $script:failed++
        "ECHEC $Name : $(@($Diffs).Count) ecart(s) sur $Total"
        $Diffs | Select-Object -First 20 | ForEach-Object { "   $_" }
    } else { "OK    $Name : $Total fichier(s) conformes" }
}

$refSet = @('Source', 'Config', 'LifePlay.uproject', 'Content\BPs', 'Content\Structs', 'Plugins\ModdingExtra\Source', 'Plugins\StreetMap\Source')

if ($InitRef427) {
    if (Test-Path $refCsv) { throw "Empreinte deja presente : $refCsv (supprimer volontairement pour la refaire)" }
    Hash-Tree $Root427 $refSet | Export-Csv $refCsv -NoTypeInformation -Encoding UTF8
    "Empreinte 4.27 ecrite : $refCsv"
}

if ($Modules) {
    $a = Hash-Tree $Root427 @('Content\Modules'); $b = Hash-Tree $ProjectRoot @('Content\Modules')
    $ha = @{}; $a | ForEach-Object { $ha[$_.Rel] = $_.MD5 }
    $hb = @{}; $b | ForEach-Object { $hb[$_.Rel] = $_.MD5 }
    $keys = @($ha.Keys) + @($hb.Keys) | Sort-Object -Unique
    $d = $keys | Where-Object { $ha[$_] -ne $hb[$_] } | ForEach-Object { if (-not $ha[$_]) { "en plus en 5.5 : $_" } elseif (-not $hb[$_]) { "absent en 5.5 : $_" } else { "different : $_" } }
    Report 'T-STAT-02 Modules = 4.27' $d $keys.Count
}

if ($Env) {
    $man = Join-Path $BackupRoot 'L0\manifest.csv'
    $rows = Import-Csv $man | Where-Object { $_.Rel -match '^(\.claude\\|\.mcp\.json$|Saved\\Backups\\|Saved\\SaveGames\\)' }
    $d = foreach ($r in $rows) {
        $p = Join-Path $ProjectRoot $r.Rel
        if (-not (Test-Path -LiteralPath $p)) { "absent : $($r.Rel)" }
        elseif ((Get-FileHash -LiteralPath $p -Algorithm MD5).Hash -ne $r.MD5) {
            # Les .sav changent quand on joue : signales mais non bloquants
            if ($r.Rel -like 'Saved\SaveGames\*') { Write-Host "   (info) sauvegarde de jeu modifiee : $($r.Rel)" } else { "modifie : $($r.Rel)" }
        }
    }
    Report 'T-STAT-03 environnement = L0' $d @($rows).Count
}

if ($Ref427) {
    if (-not (Test-Path $refCsv)) { throw "Pas d'empreinte 4.27 : lancer -InitRef427 d'abord" }
    $ref = Import-Csv $refCsv
    $cur = @{}; Hash-Tree $Root427 $refSet | ForEach-Object { $cur[$_.Rel] = $_.MD5 }
    $d = @($ref | Where-Object { $cur[$_.Rel] -ne $_.MD5 } | ForEach-Object { "modifie ou absent : $($_.Rel)" })
    $known = @{}; $ref | ForEach-Object { $known[$_.Rel] = 1 }
    $d += @($cur.Keys | Where-Object { -not $known[$_] } | ForEach-Object { "nouveau : $_" })
    Report 'T-STAT-04 arbre 4.27 inchange' $d @($ref).Count
}

if ($failed) { exit 1 }