Generate SharePoint Site Inventory Report

$AdminCenterURL="https://contoso-admin.sharepoint.com/"

##
.SYNOPSIS
Generates a SharePoint Online site inventory report.

.DESCRIPTION
Connects to a SharePoint Online site using PnP PowerShell and  
exports key site information including title, URL, template,  
creation date, lists and document libraries count.

.PARAMETER SiteUrl
URL of the SharePoint Online site.

.PARAMETER OutputFolder
Folder where the CSV report will be generated.

.EXAMPLE
.\Generate-SPSiteInventory.ps1 `
    -SiteUrl "https://contoso.sharepoint.com/sites/PMO"

.NOTES
Author: Antonio Villarruel
#>

param(
    [Parameter(Mandatory = $true)]
    [string]$SiteUrl,

    [string]$OutputFolder = "."
)

Write-Host "Connecting to SharePoint site..." -ForegroundColor Cyan

try {
    Connect-PnPOnline -Url $SiteUrl -Interactive
}
catch {
    Write-Error "Unable to connect to the SharePoint site."
    exit
}

Write-Host "Retrieving site information..." -ForegroundColor Cyan

try {
    $web = Get-PnPWeb -Includes Title, Url, WebTemplate, Created
    $lists = Get-PnPList
    $libraries = $lists | Where-Object {
        $_.BaseTemplate -eq 101
    }

    $inventory = [PSCustomObject]@{
        SiteTitle         = $web.Title
        SiteUrl           = $web.Url
        Template          = $web.WebTemplate
        CreatedDate       = $web.Created
        TotalLists        = $lists.Count
        DocumentLibraries = $libraries.Count
        GeneratedDate     = Get-Date
    }

    if (!(Test-Path $OutputFolder)) {
        New-Item -ItemType Directory -Path $OutputFolder | Out-Null
    }

    $outputFile = Join-Path `
        $OutputFolder `
        "SharePointSiteInventory.csv"

    # Export inventory report to CSV
    $inventory | Export-Csv `
        -Path $outputFile `
        -NoTypeInformation `
        -Encoding UTF8

    Write-Host ""
    Write-Host "Inventory generated successfully!" -ForegroundColor Green
    Write-Host "File: $outputFile"
}
catch {
    Write-Error "Error generating inventory report."
}