<#
.SYNOPSIS
List Tanium **Sensors** via the REST API, using Url/Token from `config.json` by default.
Shows: Id, Name, Content Set, Category, Parameters?, CacheSeconds (if exposed).
Supports filters by name/content set/category, Out‑GridView, and CSV export.

.USAGE
# Basic (reads config.json in the same folder)
./List-Sensors.ps1

# Filter by name/content set/category (regex), show grid and export CSV
./List-Sensors.ps1 -NameLike '^BIOS' -ContentSetLike 'Deploy' -CategoryLike 'Hardware' -Grid -ExportCsv C:\Temp\sensors.csv

# Raw JSON
./List-Sensors.ps1 -Raw

# Override Url/Token explicitly
./List-Sensors.ps1 -Url tanium.pp.dktinfra.io -Token 'token-xxxx'
#>

param(
  [string]$Url,
  [string]$Token,
  [switch]$SkipCertCheck,

  [string]$NameLike,
  [string]$ContentSetLike,
  [string]$CategoryLike,

  [switch]$Raw,
  [switch]$Grid,
  [string]$ExportCsv
)

$ErrorActionPreference = 'Stop'
try { [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12 } catch {}

# ---------- Helpers ----------
function New-BaseUri([string]$HostLike) {
  $h = $HostLike.Trim()
  if ($h -match '^https?://') { $h = $h -replace '^https?://','' }
  $h = $h.TrimEnd('/')
  if ([string]::IsNullOrWhiteSpace($h)) { throw 'TaniumUrl empty after normalization.' }
  "https://$h"
}

# TLS bypass for Windows PowerShell 5.1
$script:__oldCb = $null
function Enter-InsecureTls { param([switch]$Enable)
  if (-not $Enable) { return }
  $script:__oldCb = [System.Net.ServicePointManager]::ServerCertificateValidationCallback
  $cb = [System.Net.Security.RemoteCertificateValidationCallback]{ param($s,$c,$ch,$e) $true }
  [System.Net.ServicePointManager]::ServerCertificateValidationCallback = $cb
}
function Exit-InsecureTls {
  if ($script:__oldCb -ne $null) {
    [System.Net.ServicePointManager]::ServerCertificateValidationCallback = $script:__oldCb
    $script:__oldCb = $null
  }
}

# ---------- Load config if needed ----------
$BaseDir    = if ($PSScriptRoot) { $PSScriptRoot } else { $pwd.Path }
$configPath = Join-Path $BaseDir 'config.json'
if (-not $Url -or -not $Token) {
  if (-not (Test-Path $configPath)) { throw "Missing -Url/-Token and config.json not found: $configPath" }
  $cfg = Get-Content -Path $configPath -Raw | ConvertFrom-Json
  if (-not $Url)   { $Url   = [string]$cfg.TaniumUrl }
  if (-not $Token) { $Token = [string]$cfg.TaniumApiToken }
  if (-not $PSBoundParameters.ContainsKey('SkipCertCheck')) { $SkipCertCheck = [bool]$cfg.SkipCertificateCheck }
}

$Base    = New-BaseUri $Url
$Headers = @{ session = $Token; 'Content-Type' = 'application/json' }

function Invoke-Tanium([string]$Method,[string]$Path,[object]$BodyObj) {
  $uri  = if ($Path -match '^https?://') { $Path } else { "$Base$Path" }
  $body = if ($null -ne $BodyObj) { $BodyObj | ConvertTo-Json -Depth 10 } else { $null }
  $ps7  = ($PSVersionTable.PSVersion.Major -ge 7)
  if ($ps7 -and $SkipCertCheck) {
    return Invoke-RestMethod -SkipCertificateCheck -Method $Method -Uri $uri -Headers $Headers -Body $body
  } else {
    try { Enter-InsecureTls -Enable:$SkipCertCheck; return Invoke-RestMethod -Method $Method -Uri $uri -Headers $Headers -Body $body }
    finally { Exit-InsecureTls }
  }
}

# ---------- Fetch Sensors + Content Sets (for names) ----------
$resp = Invoke-Tanium GET "/api/v2/sensors" $null
$sensors = if ($resp.data) { $resp.data } elseif ($resp.items) { $resp.items } else { $resp }

$csResp = Invoke-Tanium GET "/api/v2/content_sets" $null
$contentSets = if ($csResp.data) { $csResp.data } elseif ($csResp.items) { $csResp.items } else { $csResp }
$csById = @{}
foreach ($cs in $contentSets) { if ($cs.id -ne $null) { $csById[$cs.id] = $cs } }

if ($Raw) {
  [pscustomobject]@{ sensors = $sensors; contentSets = $contentSets } | ConvertTo-Json -Depth 14
  return
}

if (-not $sensors) { Write-Output 'No sensors returned.'; return }

# ---------- Helpers to read maybe-present fields ----------
function TryField($obj, $path) {
  try {
    $val = $obj
    foreach ($p in ($path -split '\.')) {
      if ($null -eq $val) { return $null }
      $pp = $val.PSObject.Properties[$p]
      if (-not $pp) { return $null }
      $val = $pp.Value
    }
    return $val
  } catch { return $null }
}

# ---------- Shape output ----------
$rows = foreach ($s in $sensors) {
  $name = TryField $s 'name'
  if ($NameLike -and $name -and -not ($name -match $NameLike)) { continue }

  # content set: could be nested or just id
  $csName = ''
  $csId   = TryField $s 'content_set.id'
  if ($null -eq $csId) { $csId = TryField $s 'content_set_id' }
  if ($null -ne $csId -and $csById.ContainsKey($csId)) { $csName = $csById[$csId].name }
  if ($ContentSetLike -and $csName -and -not ($csName -match $ContentSetLike)) { continue }

  $category = TryField $s 'category'
  if ($CategoryLike -and $category -and -not ($category -match $CategoryLike)) { continue }

  $hasParams = $false
  if (TryField $s 'parameters') { $hasParams = $true }
  elseif (TryField $s 'parameter_definitions') { $hasParams = $true }
  elseif (TryField $s 'parameterDefinitions') { $hasParams = $true }

  $cacheSec = TryField $s 'expiration_seconds'
  if ($null -eq $cacheSec) { $cacheSec = TryField $s 'cache_seconds' }

  [pscustomobject]@{
    Id           = TryField $s 'id'
    Name         = $name
    ContentSet   = $csName
    Category     = $category
    Parameters   = $hasParams
    CacheSeconds = $cacheSec
  }
}

if (-not $rows) { Write-Output 'No matching sensors.'; return }
$rowsSorted = $rows | Sort-Object Name

if ($ExportCsv) {
  try { $rowsSorted | Export-Csv -NoTypeInformation -Encoding UTF8 -Path $ExportCsv; Write-Host "Exported to: $ExportCsv" -ForegroundColor Green }
  catch { Write-Warning "CSV export failed: $($_.Exception.Message)" }
}

if ($Grid) {
  $title = "Sensors — {0} item(s)" -f ($rowsSorted.Count)
  if (Get-Command Out-GridView -ErrorAction SilentlyContinue) { $rowsSorted | Out-GridView -Title $title; return }
  else { Write-Warning "Out-GridView not available. On PS7+: Install-Module Microsoft.PowerShell.GraphicalTools" }
}

$rowsSorted | Format-Table -AutoSize