<#
.SYNOPSIS
    GitLab Projekt-Inventar fuer pathOS / Bestellsystem
.DESCRIPTION
    Zieht alle Projekte aus der GitLab-Gruppe und erstellt eine strukturierte Uebersicht.
    Kompatibel mit PowerShell 5.1 — keine zusaetzlichen Installationen noetig.
#>

$GitLabUrl   = "https://git.tech.rz.db.de"
$GroupPath   = "bestellsystem1"
$ApiBase     = "$GitLabUrl/api/v4"
$PerPage     = 100
$ScriptDir   = Split-Path -Parent $MyInvocation.MyCommand.Path
$OutputDir   = Join-Path (Split-Path -Parent $ScriptDir) "data\gitlab-inventory"

# SSL-Handling (auskommentieren falls selbstsigniertes Zertifikat)
# [System.Net.ServicePointManager]::ServerCertificateValidationCallback = { $true }

# TLS 1.2 erzwingen
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12

# Token
$Token = Read-Host -Prompt "GitLab Personal Access Token (read_api)"

$Headers = @{ "PRIVATE-TOKEN" = $Token }

function Safe-String($val) {
    if ($null -eq $val) { return "" }
    return [string]$val
}

function Invoke-GitLabApi {
    param([string]$Endpoint, [hashtable]$Params = @{})
    $Params["per_page"] = $PerPage
    $AllResults = @()
    $Page = 1
    do {
        $Params["page"] = $Page
        $QS = ($Params.GetEnumerator() | ForEach-Object { "$($_.Key)=$($_.Value)" }) -join "&"
        $Uri = "$ApiBase$Endpoint`?$QS"
        try {
            $Resp = Invoke-WebRequest -Uri $Uri -Headers $Headers -UseBasicParsing -ErrorAction Stop
            $Data = $Resp.Content | ConvertFrom-Json
            if ($null -eq $Data) { break }
            if ($Data -is [array]) {
                if ($Data.Count -eq 0) { break }
                $AllResults += $Data
            } else {
                return $Data
            }
            $TP = 1
            if ($Resp.Headers["X-Total-Pages"]) { $TP = [int]$Resp.Headers["X-Total-Pages"] }
            Write-Host "  Seite $Page/$TP ($($Data.Count) Eintraege)" -ForegroundColor DarkGray
            $Page++
        } catch {
            Write-Host "  FEHLER: $($_.Exception.Message)" -ForegroundColor Red
            throw
        }
    } while ($Page -le $TP)
    return $AllResults
}

function Get-ProjectLanguages($ProjectId) {
    try {
        $Uri = "$ApiBase/projects/$ProjectId/languages"
        $R = Invoke-WebRequest -Uri $Uri -Headers $Headers -UseBasicParsing -ErrorAction Stop
        return ($R.Content | ConvertFrom-Json)
    } catch { return $null }
}

function Get-ProjectReadme($ProjectId) {
    foreach ($Branch in @("main", "master", "develop")) {
        try {
            $Uri = "$ApiBase/projects/$ProjectId/repository/files/README.md/raw?ref=$Branch"
            $R = Invoke-WebRequest -Uri $Uri -Headers $Headers -UseBasicParsing -ErrorAction Stop
            $C = $R.Content
            if ($C.Length -gt 3000) { $C = $C.Substring(0, 3000) + "`n`n... (gekuerzt)" }
            return $C
        } catch { continue }
    }
    return $null
}

function Get-RepoTree($ProjectId) {
    foreach ($Branch in @("main", "master", "develop")) {
        try {
            $Uri = "$ApiBase/projects/$ProjectId/repository/tree?ref=$Branch&per_page=100"
            $R = Invoke-WebRequest -Uri $Uri -Headers $Headers -UseBasicParsing -ErrorAction Stop
            return ($R.Content | ConvertFrom-Json)
        } catch { continue }
    }
    return @()
}

function Get-ProjectTags($Project, $Languages, $Tree) {
    $Tags = @()
    $Name = (Safe-String $Project.name).ToLower()
    $Desc = (Safe-String $Project.description).ToLower()
    $Files = @($Tree | ForEach-Object { $_.name.ToLower() })

    if ($Languages) {
        $LangProps = $Languages | Get-Member -MemberType NoteProperty
        foreach ($lp in $LangProps) {
            $lang = $lp.Name.ToLower()
            if ($lang -eq "java") { $Tags += "java" }
            if ($lang -eq "kotlin") { $Tags += "kotlin" }
            if ($lang -match "typescript|javascript") { $Tags += "frontend" }
            if ($lang -eq "python") { $Tags += "python" }
        }
    }

    if ("pom.xml" -in $Files) { $Tags += "maven" }
    if ("build.gradle" -in $Files -or "build.gradle.kts" -in $Files) { $Tags += "gradle" }
    if ("package.json" -in $Files) { $Tags += "npm" }
    if ("Dockerfile" -in $Files -or "dockerfile" -in $Files) { $Tags += "docker" }

    if ($Name -match "lib|library|common|shared|util" -or $Desc -match "lib|library|common|shared|util") { $Tags += "library" }
    if ($Name -match "service|api|backend" -or $Desc -match "service|api|backend") { $Tags += "service" }
    if ($Name -match "ui|frontend|web|app" -or $Desc -match "ui|frontend|web|app") { $Tags += "frontend-app" }
    if ($Name -match "test|e2e|integration" -or $Desc -match "test|e2e|integration") { $Tags += "testing" }
    if ($Name -match "config|infra|deploy|pipeline|ci" -or $Desc -match "config|infra|deploy|pipeline|ci") { $Tags += "infrastructure" }

    if ($Project.last_activity_at) {
        try {
            $Last = [DateTime]::Parse($Project.last_activity_at)
            $Days = ((Get-Date) - $Last).Days
            if ($Days -gt 365) { $Tags += "inactive-1y+" }
            elseif ($Days -gt 180) { $Tags += "inactive-6m+" }
        } catch {}
    }
    if ($Project.archived) { $Tags += "archived" }

    return ($Tags | Select-Object -Unique)
}

# === MAIN ===
Write-Host "============================================================" -ForegroundColor Cyan
Write-Host "  pathOS / Bestellsystem - GitLab Projekt-Inventar" -ForegroundColor Cyan
Write-Host "============================================================" -ForegroundColor Cyan
Write-Host "  GitLab: $GitLabUrl"
Write-Host "  Gruppe: $GroupPath"

New-Item -ItemType Directory -Path $OutputDir -Force | Out-Null
New-Item -ItemType Directory -Path "$OutputDir\readmes" -Force | Out-Null

try {
    Write-Host "`n>> Lade Gruppeninfo..." -ForegroundColor Yellow
    $EncodedGroup = [Uri]::EscapeDataString($GroupPath)
    $GroupInfo = Invoke-GitLabApi -Endpoint "/groups/$EncodedGroup"
    Write-Host "  Gruppe: $($GroupInfo.name) (ID: $($GroupInfo.id))" -ForegroundColor Green

    Write-Host "`n>> Lade Untergruppen..." -ForegroundColor Yellow
    $Subgroups = @(Invoke-GitLabApi -Endpoint "/groups/$EncodedGroup/subgroups" -Params @{ all_available = "true" })
    Write-Host "  $($Subgroups.Count) Untergruppen" -ForegroundColor Green

    Write-Host "`n>> Lade alle Projekte..." -ForegroundColor Yellow
    $Projects = @(Invoke-GitLabApi -Endpoint "/groups/$EncodedGroup/projects" -Params @{
        include_subgroups = "true"; with_shared = "false"; order_by = "name"; sort = "asc"
    })
    Write-Host "  $($Projects.Count) Projekte" -ForegroundColor Green

    Write-Host "`n>> Reichere Projekte an..." -ForegroundColor Yellow
    $Enriched = @()
    $Total = $Projects.Count
    $i = 0
    foreach ($P in $Projects) {
        $i++
        Write-Host "  [$i/$Total] $($P.name)..." -NoNewline
        $Langs = Get-ProjectLanguages $P.id
        $Readme = Get-ProjectReadme $P.id
        $Tree = @(Get-RepoTree $P.id)
        $Tags = @(Get-ProjectTags $P $Langs $Tree)

        $Obj = [PSCustomObject]@{
            id          = $P.id
            name        = $P.name
            path        = $P.path_with_namespace
            description = Safe-String $P.description
            branch      = $P.default_branch
            archived    = $P.archived
            created     = $P.created_at
            last_active = $P.last_activity_at
            namespace   = $P.namespace.full_path
            web_url     = $P.web_url
            languages   = $Langs
            tags        = $Tags
            files       = @($Tree | ForEach-Object { $_.name })
            readme      = $Readme
        }
        $Enriched += $Obj

        if ($Readme) {
            $SafeName = $P.path_with_namespace -replace "/", "__"
            "# $($P.name)`n`n> Quelle: $($P.web_url)`n`n$Readme" | Out-File "$OutputDir\readmes\$SafeName.md" -Encoding UTF8
        }
        Write-Host " OK" -ForegroundColor Green
    }

    # JSON
    $Enriched | ConvertTo-Json -Depth 10 | Out-File "$OutputDir\projects-full.json" -Encoding UTF8
    Write-Host "`n  JSON gespeichert" -ForegroundColor DarkGray

    # CSV
    $CsvRows = $Enriched | ForEach-Object {
        $LS = ""
        if ($_.languages) {
            $LP = $_.languages | Get-Member -MemberType NoteProperty
            $LS = ($LP | ForEach-Object { $_.Name }) -join ", "
        }
        [PSCustomObject]@{
            Name=$_.name; Pfad=$_.path; Beschreibung=$_.description;
            Sprachen=$LS; Tags=($_.tags -join ", "); LetzteAktivitaet=$_.last_active;
            Archiviert=$_.archived; Branch=$_.branch; Namespace=$_.namespace
        }
    }
    $CsvRows | Export-Csv "$OutputDir\projects-overview.csv" -Delimiter ";" -Encoding UTF8 -NoTypeInformation
    Write-Host "  CSV gespeichert" -ForegroundColor DarkGray

    # Markdown
    $Md = @("# GitLab Projektuebersicht - $(Safe-String $GroupInfo.name)", "",
        "> Generiert: $(Get-Date -Format 'yyyy-MM-dd HH:mm')",
        "> Projekte: $($Enriched.Count)", "")
    if ($Subgroups.Count -gt 0) {
        $Md += "## Untergruppen"; $Md += ""
        foreach ($sg in $Subgroups) { $Md += "- **$($sg.name)** (``$($sg.full_path)``)" }
        $Md += ""
    }
    $ByNs = $Enriched | Group-Object -Property namespace
    foreach ($G in ($ByNs | Sort-Object Name)) {
        $Md += "## $($G.Name)"; $Md += ""
        $Md += "| Projekt | Beschreibung | Sprachen | Tags | Aktiv |"
        $Md += "|---------|-------------|----------|------|-------|"
        foreach ($p in $G.Group) {
            $LS = ""; if ($p.languages) { $LP = $p.languages | Get-Member -MemberType NoteProperty; $LS = ($LP | ForEach-Object { $_.Name }) -join ", " }
            $TS = ($p.tags -join ", ")
            $DS = if ($p.description.Length -gt 60) { $p.description.Substring(0,60) + "..." } else { $p.description }
            if (-not $DS) { $DS = "-" }
            $LA = if ($p.last_active) { $p.last_active.Substring(0,10) } else { "-" }
            $Md += "| $($p.name) | $DS | $LS | $TS | $LA |"
        }
        $Md += ""
    }
    $Md -join "`n" | Out-File "$OutputDir\projects-overview.md" -Encoding UTF8
    Write-Host "  Markdown gespeichert" -ForegroundColor DarkGray

    # Statistiken
    $St = @("# Projektstatistiken", "", "- Projekte: $($Enriched.Count)", "- Untergruppen: $($Subgroups.Count)",
        "- Archiviert: $(($Enriched | Where-Object { $_.archived }).Count)", "", "## Sprachen")
    $LC = @{}; foreach ($p in $Enriched) { if ($p.languages) { $p.languages | Get-Member -MemberType NoteProperty | ForEach-Object { $LC[$_.Name] = ($LC[$_.Name]) + 1 } } }
    foreach ($e in ($LC.GetEnumerator() | Sort-Object Value -Descending)) { $St += "- $($e.Key): $($e.Value)" }
    $St += ""; $St += "## Tags"
    $TC = @{}; foreach ($p in $Enriched) { foreach ($t in $p.tags) { $TC[$t] = ($TC[$t]) + 1 } }
    foreach ($e in ($TC.GetEnumerator() | Sort-Object Value -Descending)) { $St += "- $($e.Key): $($e.Value)" }
    $St -join "`n" | Out-File "$OutputDir\statistics.md" -Encoding UTF8
    Write-Host "  Statistiken gespeichert" -ForegroundColor DarkGray

    Write-Host "`n============================================================" -ForegroundColor Green
    Write-Host "  FERTIG! $($Enriched.Count) Projekte inventarisiert." -ForegroundColor Green
    Write-Host "  Ergebnisse: $OutputDir" -ForegroundColor Green
    Write-Host "============================================================" -ForegroundColor Green

} catch {
    Write-Host "`nFEHLER: $($_.Exception.Message)" -ForegroundColor Red
    if ($_.Exception.Message -match "401") { Write-Host "  Token pruefen (read_api Scope)." -ForegroundColor Yellow }
    if ($_.Exception.Message -match "404") { Write-Host "  Gruppe '$GroupPath' nicht gefunden." -ForegroundColor Yellow }
    if ($_.Exception.Message -match "resolve|Remotename") { Write-Host "  VPN aktiv?" -ForegroundColor Yellow }
    exit 1
}