<#
.SYNOPSIS
    win-acme DNS-01 validation hook for cPanel-hosted zones (hosting.com).

.DESCRIPTION
    Creates / deletes the _acme-challenge TXT record via the cPanel API so the
    wildcard certificate *.roa.romfast.ro renews FULLY UNATTENDED (no manual TXT).

    Replaces the old "[Manual]" validation of the wildcard renewal in win-acme,
    which could not run from the scheduled task and accumulated 60+ errors until
    the certificate expired (incident 2026-05-31, see README).

    Authentication uses a cPanel API token (cPanel -> Manage API Tokens), passed
    as the header:  Authorization: cpanel <USER>:<TOKEN>

    Modern panels (cPanel & WHM v90+) -> UAPI DNS::mass_edit_zone (default).
    Legacy panels (only API2 ZoneEdit) -> set "LegacyZoneEdit": true in config.

.PARAMETER Action
    create | delete   (win-acme calls the script once for each)

.PARAMETER RecordName
    Full record name, e.g. _acme-challenge.roa.romfast.ro   (win-acme {RecordName})

.PARAMETER Token
    TXT value to publish, supplied by the ACME server        (win-acme {Token})

.NOTES
    Place on VM 201 at:  C:\Tools\win-acme\cpanel-acme-dns.ps1
    Credentials live in: C:\Tools\win-acme\cpanel-dns.config.json  (NEVER commit)
    Template:            cpanel-dns.config.example.json

    Configure the renewal with "wacs.exe" (as Administrator):
        M  -> Create renewal (full options)
        Source:       Manual            -> *.roa.romfast.ro
        Validation:   dns-01 -> "Create verification records with your own script"
            Run create: Powershell.exe -File C:\Tools\win-acme\cpanel-acme-dns.ps1
            Create args : create {RecordName} {Token}
            Run delete: Powershell.exe -File C:\Tools\win-acme\cpanel-acme-dns.ps1
            Delete args : delete {RecordName} {Token}
        Store:        Windows Certificate Store (My)
        Installation: IIS -> site "roa-apps"   (re-binds the cert automatically)

    Manual test before wiring into win-acme:
        .\cpanel-acme-dns.ps1 create _acme-challenge.roa.romfast.ro testvalue123
        (check the TXT appears in cPanel Zone Editor, then:)
        .\cpanel-acme-dns.ps1 delete _acme-challenge.roa.romfast.ro testvalue123
#>
[CmdletBinding()]
param(
    [Parameter(Mandatory)][ValidateSet('create', 'delete')][string]$Action,
    [Parameter(Mandatory)][string]$RecordName,
    [Parameter(Mandatory)][string]$Token
)

$ErrorActionPreference = 'Stop'
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12

# --- load config -----------------------------------------------------------
$cfgPath = Join-Path $PSScriptRoot 'cpanel-dns.config.json'
if (-not (Test-Path $cfgPath)) {
    throw "Missing config: $cfgPath  (copy cpanel-dns.config.example.json and fill it in)"
}
$cfg = Get-Content $cfgPath -Raw | ConvertFrom-Json

# Tolerate Hostname pasted as a URL ("https://host/cpanel", "host:2083", ...):
# keep only the bare hostname.
$cpHost = ($cfg.Hostname -replace '^\s*https?://', '') -replace '/.*$', '' -replace ':\d+\s*$', ''
$cpPort = if ($cfg.Port) { $cfg.Port } else { 2083 }
$cpUser = $cfg.User
$cpTok  = $cfg.ApiToken
$ttl    = if ($cfg.Ttl) { [int]$cfg.Ttl } else { 300 }
$legacy = [bool]$cfg.LegacyZoneEdit

if (-not $cpHost -or -not $cpUser -or -not $cpTok) {
    throw "Config incomplete: Hostname, User and ApiToken are required in $cfgPath"
}

$headers = @{ Authorization = "cpanel ${cpUser}:${cpTok}" }
$base    = "https://${cpHost}:${cpPort}"
$dname   = $RecordName.TrimEnd('.') + '.'          # cPanel wants FQDN with trailing dot

function Invoke-Uapi {
    param([string]$Module, [string]$Func, [hashtable]$Params)
    $qs = ($Params.GetEnumerator() | ForEach-Object {
            "$($_.Key)=$([uri]::EscapeDataString([string]$_.Value))"
        }) -join '&'
    $uri = "$base/execute/$Module/$Func"
    if ($qs) { $uri += "?$qs" }
    $r = Invoke-RestMethod -Uri $uri -Headers $headers -Method Get
    if ($r.errors) { throw "cPanel UAPI ${Module}::${Func} -> $($r.errors -join '; ')" }
    return $r
}

# Find the apex zone managed by cPanel that the record belongs to.
# _acme-challenge.roa.romfast.ro -> tries roa.romfast.ro, then romfast.ro
function Resolve-Zone {
    param([string]$fqdn)
    $labels = $fqdn.TrimEnd('.').Split('.')
    for ($i = 1; $i -le $labels.Count - 2; $i++) {
        $cand = ($labels[$i..($labels.Count - 1)]) -join '.'
        try {
            $r = Invoke-Uapi 'DNS' 'parse_zone' @{ zone = $cand }
            if ($r.data) { return [pscustomobject]@{ Zone = $cand; Data = $r.data } }
        }
        catch { }
    }
    throw "No cPanel-managed zone found for $fqdn"
}

function Get-ZoneSerial {
    param($zoneData)
    foreach ($l in $zoneData) {
        if ($l.type -eq 'record' -and $l.record_type -eq 'SOA') {
            $vals = $l.data_b64 | ForEach-Object {
                [Text.Encoding]::UTF8.GetString([Convert]::FromBase64String($_))
            }
            return [int64]$vals[2]   # SOA: primary, hostmaster, SERIAL, refresh, ...
        }
    }
    throw 'SOA serial not found in parsed zone'
}

# ---------------------------------------------------------------------------
# Legacy path: cPanel API2 ZoneEdit (only if panel lacks UAPI DNS module)
# ---------------------------------------------------------------------------
if ($legacy) {
    $z = Resolve-Zone $RecordName
    $name = $RecordName.TrimEnd('.')
    if ($Action -eq 'create') {
        $uri = "$base/json-api/cpanel?cpanel_jsonapi_user=$cpUser&cpanel_jsonapi_apiversion=2" +
               "&cpanel_jsonapi_module=ZoneEdit&cpanel_jsonapi_func=add_zone_record" +
               "&domain=$($z.Zone)&name=$([uri]::EscapeDataString($name))&type=TXT" +
               "&txtdata=$([uri]::EscapeDataString($Token))&ttl=$ttl"
        $r = Invoke-RestMethod -Uri $uri -Headers $headers -Method Get
        if ($r.cpanelresult.error) { throw $r.cpanelresult.error }
        Write-Host "[create] TXT $name added to $($z.Zone) (legacy ZoneEdit)"
    }
    else {
        $look = "$base/json-api/cpanel?cpanel_jsonapi_user=$cpUser&cpanel_jsonapi_apiversion=2" +
                "&cpanel_jsonapi_module=ZoneEdit&cpanel_jsonapi_func=fetchzone_records&domain=$($z.Zone)&type=TXT"
        $r = Invoke-RestMethod -Uri $look -Headers $headers -Method Get
        $hits = @($r.cpanelresult.data | Where-Object {
                ($_.name.TrimEnd('.') -eq $name) -and ($_.txtdata -eq $Token)
            } | Sort-Object { [int]$_.line } -Descending)
        foreach ($rec in $hits) {
            $del = "$base/json-api/cpanel?cpanel_jsonapi_user=$cpUser&cpanel_jsonapi_apiversion=2" +
                   "&cpanel_jsonapi_module=ZoneEdit&cpanel_jsonapi_func=remove_zone_record&domain=$($z.Zone)&line=$($rec.line)"
            Invoke-RestMethod -Uri $del -Headers $headers -Method Get | Out-Null
            Write-Host "[delete] TXT line $($rec.line) removed from $($z.Zone) (legacy ZoneEdit)"
        }
    }
    return
}

# ---------------------------------------------------------------------------
# Modern path: UAPI DNS::mass_edit_zone (serial-checked, atomic)
# ---------------------------------------------------------------------------
if ($Action -eq 'create') {
    $z = Resolve-Zone $RecordName
    $serial = Get-ZoneSerial $z.Data
    # mass_edit_zone wants 'add' as a raw JSON record object (NOT base64).
    $rec = @{ dname = $dname; ttl = $ttl; record_type = 'TXT'; data = @($Token) } | ConvertTo-Json -Compress
    Invoke-Uapi 'DNS' 'mass_edit_zone' @{ zone = $z.Zone; serial = $serial; add = $rec } | Out-Null
    Write-Host "[create] TXT $dname = $Token added to zone $($z.Zone)"
}
else {
    # Re-parse before each removal: line_index and serial shift after every edit.
    for ($pass = 0; $pass -lt 10; $pass++) {
        $z = Resolve-Zone $RecordName
        $serial = Get-ZoneSerial $z.Data
        # parse_zone returns names RELATIVE to the zone (e.g. "_acme-challenge.roa"),
        # so match against both the absolute and the zone-relative form.
        $want = $RecordName.TrimEnd('.')
        $wantRel = $want -replace ('\.' + [regex]::Escape($z.Zone) + '$'), ''
        $idx = $null
        foreach ($l in $z.Data) {
            if ($l.type -eq 'record' -and $l.record_type -eq 'TXT') {
                $n = ([Text.Encoding]::UTF8.GetString([Convert]::FromBase64String($l.dname_b64))).TrimEnd('.')
                $d = $l.data_b64 | ForEach-Object {
                    [Text.Encoding]::UTF8.GetString([Convert]::FromBase64String($_))
                }
                if ((($n -eq $want) -or ($n -eq $wantRel)) -and ($d -contains $Token)) {
                    $idx = $l.line_index; break
                }
            }
        }
        if ($null -eq $idx) { break }
        Invoke-Uapi 'DNS' 'mass_edit_zone' @{ zone = $z.Zone; serial = $serial; remove = $idx } | Out-Null
        Write-Host "[delete] TXT line $idx removed from zone $($z.Zone)"
    }
}