#
# Capture-SiteContent.ps1 - Pull the site content from a running PXE server
# into the pxe-usb build folder, on a Windows PC.
#
# The Windows twin of scripts/capture-site-content.sh. A new PXE server
# needs content that neither the repo nor the MCL image import brings; it
# exists only on a working server. This pulls, into the build folder:
#   site-content\shared\Applications\extra\   Office, Adobe, OpenText, Java,
#       fonts, Wi-Fi profile, Zscaler (every unattend installs from it;
#       pxe-status\ is left out, the playbook deploys it)
#   site-content\images\<image>\Applications\  each image's own files and
#       folders there: GE CA certificates, the Engineering Layer payload
#       (without Install-EngineeringLayer.ps1, which the repo carries)
#   site-content\links.txt                     the links images keep there
#   site-content\SHA256SUMS                    checked by the playbook
#   bios-staging\    *.exe and models.txt from _shared\BIOS
#   boot-files\boot.wim
#   boot-tools\blancco\   the Blancco files already in that folder
#
# How: ONE ssh session (one password prompt) runs a small script on the
# server that collects those files, hashes them there (SHA-256) and streams
# them back as a tar archive. Here the archive is unpacked into a scratch
# folder and every file is checked against the server's hashes, and against
# what FAT32 can hold (under 4 GiB, no two names that differ only in case).
# Only when all of that passes does the new content replace the old. The
# server is only read.
#
# Needs: Windows 10/11 (ssh.exe and tar.exe are built in), SSH access to the
# server as pxe (from the GE network use the server's GE address).
#
# Usage: double-click Capture-SiteContent.cmd in the build folder (asks for
# the server address), or:
#   .\scripts\Capture-SiteContent.ps1 -Server 10.x.x.x
#
# Exit codes: 0 captured and verified, 1 failed (the old content is kept).

[CmdletBinding()]
param(
    [string]$Server = '',
    [string]$User = 'pxe',
    [string]$PayloadRoot = '',
    [switch]$Interactive
)

$ErrorActionPreference = 'Stop'
Set-StrictMode -Version 2

$RepoRoot = Split-Path -Parent $PSScriptRoot
if (-not $PayloadRoot) { $PayloadRoot = $RepoRoot }
$PayloadRoot = (Resolve-Path -LiteralPath $PayloadRoot).Path
$FatMax = [int64]4GB - 1

function Say([string]$m) { Write-Host $m }
function Done([int]$code) {
    if ($Interactive) { Write-Host ''; Read-Host 'Press Enter to close' | Out-Null }
    exit $code
}
function Fail([string]$m) { Write-Host "ERROR: $m" -ForegroundColor Red; Done 1 }
trap { Write-Host "ERROR: $_" -ForegroundColor Red; Done 1 }

foreach ($exe in 'ssh.exe', 'tar.exe') {
    if (-not (Get-Command $exe -ErrorAction SilentlyContinue)) { Fail "$exe not found (Windows 10 1803 or later has both)" }
}
if (-not $Server) {
    if (-not $Interactive) { Fail 'give -Server (the PXE server address; from the GE network its GE address)' }
    Say 'Address of the running PXE server to copy from.'
    Say 'From the GE network use its GE address; on the imaging switch 172.16.9.1.'
    $Server = (Read-Host 'Server').Trim()
    if (-not $Server) { Fail 'no server given' }
}
if ($Server -notmatch '^[A-Za-z0-9.\-:]+$') { Fail "not a host name or address: $Server" }

# The Blancco files to refresh: whatever is already in boot-tools\blancco
# (the server also holds files its playbook builds; those are not pulled).
$blanccoDir = Join-Path $PayloadRoot 'boot-tools\blancco'
$blancco = @()
if (Test-Path -LiteralPath $blanccoDir) {
    $blancco = @(Get-ChildItem -LiteralPath $blanccoDir -Force | ForEach-Object { $_.Name } |
        Where-Object { $_ -match '^[A-Za-z0-9._+-]+$' })
}

# --- the script that runs on the server (bash, stdout = the tar stream) -----
$remote = @'
set -euo pipefail
SHARE=${CAPTURE_SHARE:-/srv/samba/winpeapps}
WWW=${CAPTURE_WWW:-/var/www/html}
ST=$(mktemp -d /tmp/pxe-capture.XXXXXX)
trap 'rm -rf "$ST"' EXIT
SC=$ST/site-content
mkdir -p "$SC/shared/Applications" "$SC/images" "$ST/bios-staging" "$ST/boot-files" "$ST/boot-tools/blancco"
[ -d "$SHARE/_shared/Applications/extra" ] && ln -s "$SHARE/_shared/Applications/extra" "$SC/shared/Applications/extra"
printf '# image<TAB>name in Deploy/Applications<TAB>link target under winpeapps/\n' >"$SC/links.txt"
for apps in "$SHARE"/*/Deploy/Applications; do
    [ -d "$apps" ] || continue
    img=${apps#"$SHARE"/}; img=${img%%/*}
    case "$img" in _*) continue ;; esac
    for e in "$apps"/* "$apps"/.[!.]*; do
        [ -e "$e" ] || [ -L "$e" ] || continue
        n=${e##*/}
        if [ -L "$e" ]; then
            t=$(readlink "$e")
            case "$t" in
                "$SHARE"/_shared/*) printf '%s\t%s\t%s\n' "$img" "$n" "${t#"$SHARE"/}" >>"$SC/links.txt" ;;
                *) echo "WARNING: $img/Deploy/Applications/$n links outside _shared ($t); not captured" >&2 ;;
            esac
            continue
        fi
        # a real BPRT folder is an old import's copy of the vendor folder
        [ "${n,,}" = bprt ] && continue
        mkdir -p "$SC/images/$img/Applications"
        ln -s "$e" "$SC/images/$img/Applications/$n"
    done
done
for f in "$SHARE"/_shared/BIOS/*.exe "$SHARE"/_shared/BIOS/models.txt; do
    [ -f "$f" ] && ln -s "$f" "$ST/bios-staging/${f##*/}"
done
[ -f "$WWW/win11/sources/boot.wim" ] && ln -s "$WWW/win11/sources/boot.wim" "$ST/boot-files/boot.wim"
for n in "$@"; do
    [ -e "$WWW/blancco/$n" ] && ln -s "$WWW/blancco/$n" "$ST/boot-tools/blancco/$n"
done
EXCL=(--exclude=./site-content/shared/Applications/extra/pxe-status --exclude=Install-EngineeringLayer.ps1)
echo "pxe-capture: hashing on the server (a few minutes for about 12 GB)..." >&2
( cd "$ST" && find -L . -type f ! -path './site-content/shared/Applications/extra/pxe-status/*' \
      ! -name Install-EngineeringLayer.ps1 ! -name capture-SHA256SUMS -print0 |
      sort -z | xargs -0 -r sha256sum ) >"$ST/capture-SHA256SUMS.tmp"
mv "$ST/capture-SHA256SUMS.tmp" "$ST/capture-SHA256SUMS"
echo "pxe-capture: $(wc -l <"$ST/capture-SHA256SUMS") files; sending..." >&2
tar -chf - -C "$ST" "${EXCL[@]}" .
'@

$scratch = Join-Path $PayloadRoot '.capture-new'
$old = Join-Path $PayloadRoot '.capture-old'
foreach ($d in $scratch, $old) {
    if (Test-Path -LiteralPath $d) { Remove-Item -LiteralPath $d -Recurse -Force }
}
New-Item -ItemType Directory -Path $scratch | Out-Null
$remoteFile = Join-Path ([IO.Path]::GetTempPath()) ('pxe-capture-' + [guid]::NewGuid().ToString('N') + '.sh')
[IO.File]::WriteAllText($remoteFile, ($remote -replace "`r", ''), (New-Object System.Text.UTF8Encoding($false)))

Say '============================================'
Say 'PXE site content capture (Windows)'
Say '============================================'
Say "Server  : $User@$Server"
Say "Folder  : $PayloadRoot"
Say "Blancco : $($blancco.Count) known files"
Say ''
Say "[1/3] Copying from the server (enter the $User password when asked)..."
# cmd's pipe passes bytes unchanged; a PowerShell pipe would re-encode the tar.
$names = ($blancco | ForEach-Object { "'" + $_ + "'" }) -join ' '
$cmdline = "ssh.exe -o StrictHostKeyChecking=accept-new -o ServerAliveInterval=30 $User@$Server `"bash -s -- $names`" < `"$remoteFile`" | tar.exe -xf - -C `"$scratch`""
& cmd.exe /c $cmdline
$tarCode = $LASTEXITCODE
Remove-Item -LiteralPath $remoteFile -Force -ErrorAction SilentlyContinue

$sumFile = Join-Path $scratch 'capture-SHA256SUMS'
if (-not (Test-Path -LiteralPath $sumFile)) {
    Remove-Item -LiteralPath $scratch -Recurse -Force -ErrorAction SilentlyContinue
    Fail "nothing usable arrived (ssh/tar exit $tarCode): wrong address or password, or the server is not reachable. Nothing was changed."
}

Say ''
Say '[2/3] Checking every file against the server''s SHA-256...'
$lines = @([IO.File]::ReadAllLines($sumFile) | Where-Object { $_ })
$want = @{}
$lower = @{}
$errors = New-Object System.Collections.Generic.List[string]
foreach ($l in $lines) {
    if ($l -notmatch '^([0-9a-f]{64})  \./(.+)$') { $errors.Add("bad line in the server's list: $l"); continue }
    $rel = $Matches[2]
    $key = $rel.ToLowerInvariant()
    if ($lower.ContainsKey($key)) { $errors.Add("names differ only in case (one would overwrite the other): $rel / $($lower[$key])") }
    $lower[$key] = $rel
    $want[$rel] = $Matches[1]
}
$i = 0
foreach ($rel in $want.Keys) {
    $i++
    if ($i % 25 -eq 0) { Write-Progress -Activity 'Verifying' -Status $rel -PercentComplete ([int](100 * $i / $want.Count)) }
    $p = Join-Path $scratch ($rel -replace '/', '\')
    if (-not (Test-Path -LiteralPath $p -PathType Leaf)) { $errors.Add("missing: $rel"); continue }
    $f = Get-Item -LiteralPath $p
    if ($f.Length -gt $FatMax) { $errors.Add("4 GiB or more (FAT32 cannot hold it): $rel") }
    if ((Get-FileHash -LiteralPath $p -Algorithm SHA256).Hash.ToLowerInvariant() -ne $want[$rel]) { $errors.Add("differs from the server: $rel") }
}
Write-Progress -Activity 'Verifying' -Completed
if ($errors.Count -gt 0) {
    Say "$($errors.Count) problem(s); nothing was changed:"
    $errors | Select-Object -First 20 | ForEach-Object { Say "    $_" }
    Remove-Item -LiteralPath $scratch -Recurse -Force -ErrorAction SilentlyContinue
    Fail 'capture not usable (long paths? see https://learn.microsoft.com/windows/win32/fileio/maximum-file-path-limitation)'
}
Say "    $($want.Count) files match"

# site-content\SHA256SUMS in the format the playbook checks (sha256sum -c,
# paths relative to site-content), from the server's own hashes.
$sc = New-Object System.Collections.Generic.List[string]
foreach ($l in $lines) {
    if ($l -match '^([0-9a-f]{64})  \./site-content/(.+)$') { $sc.Add("$($Matches[1])  ./$($Matches[2])") }
}
[IO.File]::WriteAllText((Join-Path $scratch 'site-content\SHA256SUMS'), (($sc -join "`n") + "`n"), (New-Object System.Text.UTF8Encoding($false)))

Say ''
Say '[3/3] Replacing the old content...'
New-Item -ItemType Directory -Path $old | Out-Null
function Swap([string]$rel) {
    $new = Join-Path $scratch $rel
    if (-not (Test-Path -LiteralPath $new)) { return }
    $cur = Join-Path $PayloadRoot $rel
    if (Test-Path -LiteralPath $cur) {
        $bak = Join-Path $old $rel
        New-Item -ItemType Directory -Path (Split-Path -Parent $bak) -Force | Out-Null
        Move-Item -LiteralPath $cur -Destination $bak
    }
    New-Item -ItemType Directory -Path (Split-Path -Parent $cur) -Force | Out-Null
    Move-Item -LiteralPath $new -Destination $cur
    Say "    $rel"
}
Swap 'site-content'
Swap 'bios-staging'
Swap 'boot-files\boot.wim'
foreach ($n in $blancco) { Swap (Join-Path 'boot-tools\blancco' $n) }
Remove-Item -LiteralPath $old -Recurse -Force -ErrorAction SilentlyContinue
Remove-Item -LiteralPath $scratch -Recurse -Force -ErrorAction SilentlyContinue

$size = (Get-ChildItem -LiteralPath (Join-Path $PayloadRoot 'site-content') -Recurse -File | Measure-Object Length -Sum).Sum
Say ''
Say ('Done: site-content {0:N1} GB, {1} files. Build the USB next (Build-PxeUsb.cmd).' -f ($size / 1GB), $sc.Count)
Done 0