<#
  Applies pending db\migrations\*.asp to the production database WITHOUT redeploying the
  site - useful when the app code on the server is already current but the schema has
  drifted (e.g. a migration was added after the last full deploy, or - as happened once -
  build-release.ps1 was silently dropping db\migrations\ from every release).

  Flow:
  1. scp scripts\runMigrations.vbs and db\migrations\*.asp to a throwaway work folder in
     C:\Windows\Temp on the remote host (never touches the live site's own deploy directory).
  2. scp scripts\run-migrations-remote-apply.ps1 and run it over ssh - it copies the site's
     already-deployed public\web.config into the work folder (so it uses the real production
     connection string), runs `runMigrations.vbs status` then `up`, and deletes the work
     folder afterward.

  For a normal deploy (which also ships db\migrations and runs migrations automatically),
  use scripts\deploy-iis.ps1 instead.

  Usage:
    powershell -File scripts\run-migrations-remote.ps1

  Remote target defaults to the "ssh user@host" line in scripts\deployinfo.txt (gitignored),
  same as deploy-iis.ps1.
#>

param(
  [string]$RemoteTarget = '',
  [int]$RemotePort = 22,
  [string]$RemoteDir = 'C:\inetpub\wwwroot\Purple_Envelop_Order_Site',
  [string]$SshExe = 'ssh',
  [string]$ScpExe = 'scp'
)

$ErrorActionPreference = 'Stop'
$repoRoot = Split-Path $PSScriptRoot -Parent

function Ensure-Command {
  param([string]$Name)
  if(!(Get-Command $Name -ErrorAction SilentlyContinue)){
    throw "$Name not found on PATH"
  }
}

function Get-DefaultRemoteTarget {
  $infoPath = Join-Path $PSScriptRoot 'deployinfo.txt'
  if(!(Test-Path $infoPath)){ return '' }
  $sshLine = Get-Content $infoPath | Where-Object { $_ -match '^\s*ssh\s+' } | Select-Object -First 1
  if([string]::IsNullOrWhiteSpace($sshLine)){ return '' }
  return ($sshLine -replace '^\s*ssh\s+', '').Trim()
}

if([string]::IsNullOrWhiteSpace($RemoteTarget)){
  $RemoteTarget = Get-DefaultRemoteTarget
}
if([string]::IsNullOrWhiteSpace($RemoteTarget)){
  throw 'No -RemoteTarget given and scripts\deployinfo.txt not found. Create scripts\deployinfo.txt with a line like: ssh user@host'
}

Ensure-Command $SshExe
Ensure-Command $ScpExe

$AuthOpts = @(
  '-o', 'PreferredAuthentications=publickey,keyboard-interactive,password',
  '-o', 'NumberOfPasswordPrompts=3'
)

# --- 1. Stage a local bundle: scripts\runMigrations.vbs + db\migrations\*.asp ---
$stageDir = Join-Path $repoRoot ('dist\migrations_stage_' + (Get-Date -Format 'yyyyMMdd_HHmmss'))
New-Item -ItemType Directory -Force -Path (Join-Path $stageDir 'scripts') | Out-Null
New-Item -ItemType Directory -Force -Path (Join-Path $stageDir 'db\migrations') | Out-Null
Copy-Item (Join-Path $repoRoot 'scripts\runMigrations.vbs') (Join-Path $stageDir 'scripts\runMigrations.vbs') -Force
Copy-Item (Join-Path $repoRoot 'db\migrations\*.asp') (Join-Path $stageDir 'db\migrations') -Force

$remoteWorkDir = 'C:\Windows\Temp\pe-migrations-' + (Get-Date -Format 'yyyyMMdd_HHmmss')
$remoteApplyDest = 'C:\Windows\Temp\run-migrations-remote-apply.ps1'

# --- 2. Ship the bundle and the remote-apply script ---
# A single recursive source -> a destination that doesn't exist yet makes scp create that
# destination as a copy of the source, so this also creates $remoteWorkDir - no separate
# "ssh mkdir" step needed (the remote shell is cmd.exe, not PowerShell, so raw PowerShell
# commands passed straight through ssh don't run there without an explicit powershell.exe
# wrapper; simplest to just avoid needing one here).
Write-Host "Copying migrations bundle to $RemoteTarget"
& $ScpExe -P $RemotePort @AuthOpts -r $stageDir "${RemoteTarget}:$remoteWorkDir"
if($LASTEXITCODE -ne 0){ throw 'scp of migrations bundle failed - see scp output above for the actual reason' }

& $ScpExe -P $RemotePort @AuthOpts (Join-Path $PSScriptRoot 'run-migrations-remote-apply.ps1') "${RemoteTarget}:$remoteApplyDest"
if($LASTEXITCODE -ne 0){ throw 'scp of remote-apply script failed - see scp output above for the actual reason' }

Remove-Item -Recurse -Force $stageDir -ErrorAction SilentlyContinue

# --- 3. Apply on the remote host (also deletes $remoteWorkDir when done) ---
$remoteCommandParts = @(
  'powershell', '-NoProfile', '-ExecutionPolicy', 'Bypass',
  '-File', ('"' + $remoteApplyDest + '"'),
  '-RemoteDir', ('"' + $RemoteDir + '"'),
  '-WorkDir', ('"' + $remoteWorkDir + '"')
)

Write-Host "Applying pending migrations on $RemoteTarget"
& $SshExe -p $RemotePort @AuthOpts $RemoteTarget ($remoteCommandParts -join ' ')
if($LASTEXITCODE -ne 0){ throw 'remote migration apply failed - see ssh output above' }

Write-Host 'Done.'