[CmdletBinding()]
param(
    [Parameter(Mandatory = $true)]
    [string]$BaseBranchUrl,

    [Parameter(Mandatory = $false)]
    [string]$BranchName,

    [Parameter(Mandatory = $false)]
    [string]$Ticket,

    [Parameter(Mandatory = $false)]
    [string]$Description,

    [Parameter(Mandatory = $false)]
    [string]$AuthorInitials,

    [Parameter(Mandatory = $false)]
    [string]$CommitMessage,

    [Parameter(Mandatory = $false)]
    [string]$CheckoutPath,

    [switch]$Force,
    [switch]$WhatIfOnly
)

Set-StrictMode -Version Latest
$ErrorActionPreference = "Stop"

function Assert-SvnCli {
    if (-not (Get-Command svn -ErrorAction SilentlyContinue)) {
        throw "Le client svn n'est pas disponible dans le PATH."
    }
}

function Normalize-Slug {
    param([string]$Value)

    if ([string]::IsNullOrWhiteSpace($Value)) {
        return "modif"
    }

    $normalized = $Value.ToLowerInvariant()
    $normalized = $normalized -replace "[^a-z0-9]+", "-"
    $normalized = $normalized.Trim("-")

    if ([string]::IsNullOrWhiteSpace($normalized)) {
        return "modif"
    }

    return $normalized
}

function Get-ParentUrl {
    param([string]$Url)

    $trimmed = $Url.TrimEnd("/")
    $lastSlashIndex = $trimmed.LastIndexOf("/")
    if ($lastSlashIndex -lt 0) {
        throw "Impossible de determiner le parent de l'URL: $Url"
    }

    return $trimmed.Substring(0, $lastSlashIndex)
}

function Test-BranchExists {
    param([string]$Url)

    & svn info "$Url" *> $null
    return ($LASTEXITCODE -eq 0)
}

function New-DefaultBranchName {
    param(
        [string]$Ticket,
        [string]$Description,
        [string]$AuthorInitials
    )

    $datePart = (Get-Date).ToString("yyyyMMdd")
    $ticketPart = if ([string]::IsNullOrWhiteSpace($Ticket)) { "NO-TICKET" } else { $Ticket.Trim().ToUpperInvariant() }
    $authorPart = if ([string]::IsNullOrWhiteSpace($AuthorInitials)) { "XX" } else { $AuthorInitials.Trim().ToUpperInvariant() }
    $slugPart = Normalize-Slug -Value $Description

    return "dev_${ticketPart}_${authorPart}_${slugPart}_${datePart}"
}

function Validate-BranchName {
    param([string]$Name)

    $regex = "^dev_[A-Z0-9-]+_[A-Z]{2,5}_[a-z0-9-]+_[0-9]{8}$"
    if ($Name -notmatch $regex) {
        throw @"
Nom de branche invalide: $Name
Pattern attendu: dev_<TICKET>_<INITIALS>_<DESCRIPTION-KEBAB-CASE>_<YYYYMMDD>
Exemple: dev_SPRF-3124_HBK_fix-journalisation-404_20260319
"@
    }
}

function New-DefaultCommitMessage {
    param(
        [string]$Ticket,
        [string]$Description,
        [string]$BranchName
    )

    $ticketPart = if ([string]::IsNullOrWhiteSpace($Ticket)) { "NO-TICKET" } else { $Ticket.Trim().ToUpperInvariant() }
    $descriptionPart = if ([string]::IsNullOrWhiteSpace($Description)) { "Correctifs" } else { $Description.Trim() }

    return "$ticketPart - $descriptionPart | Branche: $BranchName"
}

Assert-SvnCli

if ([string]::IsNullOrWhiteSpace($BranchName)) {
    $BranchName = New-DefaultBranchName -Ticket $Ticket -Description $Description -AuthorInitials $AuthorInitials
}

Validate-BranchName -Name $BranchName

$baseUrl = $BaseBranchUrl.TrimEnd("/")
$parentUrl = Get-ParentUrl -Url $baseUrl
$newBranchUrl = "$parentUrl/$BranchName"

if ([string]::IsNullOrWhiteSpace($CommitMessage)) {
    $CommitMessage = New-DefaultCommitMessage -Ticket $Ticket -Description $Description -BranchName $BranchName
}

Write-Host "Base branch URL   : $baseUrl" -ForegroundColor Cyan
Write-Host "New branch name   : $BranchName" -ForegroundColor Cyan
Write-Host "New branch URL    : $newBranchUrl" -ForegroundColor Cyan
Write-Host "Create message    : $CommitMessage" -ForegroundColor Cyan
if (-not [string]::IsNullOrWhiteSpace($CheckoutPath)) {
    Write-Host "Checkout path     : $CheckoutPath" -ForegroundColor Cyan
}

if ((Test-BranchExists -Url $newBranchUrl) -and -not $Force) {
    throw "La branche existe deja: $newBranchUrl. Utilisez -Force pour continuer."
}

if ($WhatIfOnly) {
    Write-Host "Mode simulation: aucune commande svn copy/checkout executee." -ForegroundColor Yellow
    return
}

if (Test-BranchExists -Url $newBranchUrl) {
    Write-Host "La branche existe deja et -Force est actif. Aucune creation effectuee." -ForegroundColor Yellow
}
else {
    Write-Host "Creation de la branche..." -ForegroundColor Green
    & svn copy "$baseUrl" "$newBranchUrl" -m "$CommitMessage"
    if ($LASTEXITCODE -ne 0) {
        throw "Echec de creation de branche SVN."
    }
}

if (-not [string]::IsNullOrWhiteSpace($CheckoutPath)) {
    if (Test-Path -LiteralPath $CheckoutPath) {
        if (-not $Force) {
            throw "Le repertoire de checkout existe deja: $CheckoutPath. Utilisez -Force pour l'autoriser."
        }

        Write-Host "Le repertoire existe deja, checkout ignore en mode -Force." -ForegroundColor Yellow
    }
    else {
        Write-Host "Checkout de la nouvelle branche..." -ForegroundColor Green
        & svn checkout "$newBranchUrl" "$CheckoutPath"
        if ($LASTEXITCODE -ne 0) {
            throw "Echec du checkout SVN."
        }
    }
}

Write-Host "Termine." -ForegroundColor Green
Write-Host "Message de commit suggere pour les changements de code:" -ForegroundColor Cyan
Write-Host ("{0} - Correctifs journalisation (404 toleres + fallback reponse vide)" -f ($(if ([string]::IsNullOrWhiteSpace($Ticket)) { "NO-TICKET" } else { $Ticket.Trim().ToUpperInvariant() }))) -ForegroundColor Gray