<#
=============================================================================================
Name:           Microsoft Teams Shared Channel Members Report
Website:        o365reports.com

Script Highlights: 
~~~~~~~~~~~~~~~~~
1.A single script allows you to generate shared channel reports for all teams or a specific team.   
2.The script can be executed with MFA enabled accounts too.  
3.Exports output to CSV.  
4.Automatically installs Microsoft Teams PowerShell module (if not installed already) upon your confirmation.  
5.It generates 2 output files. One is shared channels report, and another is shared channel membership report. 
6.The script is scheduler friendly. I.e., Credential can be passed as a parameter instead of saving inside the script. 
7.Supports certificate-based authentication.

For detailed Script execution:  https://o365reports.com/2023/02/28/ms-teams-shared-channel-membership-report
============================================================================================
#>
param(
[string]$UserName, 
[string]$Password, 
[string]$CertificateThumbprint,
[string]$ApplicationId,
[string]$TenantId,
[string]$TeamName
) 

#Connect to Microsoft Teams
$Module=Get-Module -Name MicrosoftTeams -ListAvailable 
if($Module.count -eq 0)
{
 Write-Host MicrosoftTeams module is not available  -ForegroundColor yellow 
 $Confirm= Read-Host Are you sure you want to install module? [Y] Yes [N] No
 if($Confirm -match "[yY]")
 {
  Install-Module MicrosoftTeams -Scope CurrentUser
 }
 else
 {
  Write-Host MicrosoftTeams module is required.Please install module using Install-Module MicrosoftTeams cmdlet.
  Exit
 }
}

#Storing credential in script for scheduling purpose/ Passing credential as parameter
if(($UserName -ne "") -and ($Password -ne ""))
{
 $SecuredPassword = ConvertTo-SecureString -AsPlainText $Password -Force
 $Credential  = New-Object System.Management.Automation.PSCredential $UserName,$SecuredPassword
 Connect-MicrosoftTeams -Credential $Credential
}
elseif(($CertificateThumbprint -ne "") -and ($ApplicationId -ne "") -and ($TenantId -ne ""))
{
 Connect-MicrosoftTeams -CertificateThumbprint $CertificateThumbprint -ApplicationId $ApplicationId -TenantId $TenantId
}
else
{  
 Connect-MicrosoftTeams | Out-Null
}

Function Process_TeamChannel
{
 Get-TeamAllChannel -GroupId $TeamId -MembershipType Shared | foreach {
  $global:SharedChannelCount++
  $ChannelName=$_.DisplayName
  $Description=$_.Description
  $HostTeamId=$_.HostTeamId
  if($Description -eq $null)
  {
   $Description="-"
  }
  if($HostTeamId -eq $TeamId )
  {
   $SharedChannelType="Team hosted channel"
  }
  else
  {
   $SharedChannelType="Incoming channel"
  }
  $Membership=Get-TeamChannelUser -GroupId $HostTeamId -DisplayName $ChannelName
  $AllMembers= (@($Membership.user)-join ',')
  $MembersCount=$Membership.Count

  #Exporting shared channel summary report
  $Result = @{'Team Name'=$Teamname;'Shared Channel Name'=$ChannelName;'Shared Channel Type'=$SharedChannelType;'Description'=$Description;'Channel Members'=$AllMembers;'Members Count'=$MembersCount }
  $Results = New-Object PSObject -Property $Result
  $Results |select-object 'Team Name','Shared Channel Name','Shared Channel Type','Description','Members Count','Channel Members' | Export-Csv -Path $OutputCSVName -Notype -Append

  foreach($Member in $Membership)
  {
   $Name=$Member.Name
   $Email=$Member.User
   $Role=$Member.Role
   $Output=@{'Team Name'=$Teamname;'Shared Channel Name'=$ChannelName;'Shared Channel Type'=$SharedChannelType;'Description'=$Description;'Member Name'=$Name;'Member Email'=$Email;'Role'=$Role}
   $Outputs = New-Object PSObject -Property $Output
   $Outputs | Select-Object 'Team Name','Shared Channel Name','Shared Channel Type','Description','Member Name','Member Email','Role' | Export-Csv -Path $OutputCSV -Notype -Append
  }
 }
}

$Result=""  
$Results=@()
$Output=""
$Outputs=@() 

$OutputCSVName=".\SharedChannelReport_$((Get-Date -format yyyy-MMM-dd-ddd` hh-mm` tt).ToString()).csv"
$OutputCSV=".\Detailed_SharedChannelMembershipReport_$((Get-Date -format yyyy-MMM-dd-ddd` hh-mm` tt).ToString()).csv"
Write-Host Generating shared channel membership report...  -ForegroundColor Yellow
$ProcessedCount=0
$global:SharedChannelCount=0

#Process all teams
if($TeamName -eq "")
{
 Get-Team | foreach {
  $TeamName=$_.DisplayName
  $TeamId=$_.GroupId
  $ProcessedCount++
  Write-Progress -Activity "`n     Processed teams count: $ProcessedCount "`n"  Currently Processing team: $TeamName"
  Process_TeamChannel
 }
}

else
{
 $TeamDetails=Get-Team -DisplayName $TeamName     
 if($TeamDetails -eq $null)
 {
  Write-Host Team $TeamName is not available. Please check the team name. -ForegroundColor Red
 }
 else
 {
  $TeamId=$TeamDetails.GroupId  
  Process_TeamChannel
 }
}

#Open output file after execution  
Write-Host `nScript executed successfully 
Write-Host `n$SharedChannelCount shared channels exported in the output file.
if((Test-Path -Path $OutputCSVName) -eq "True") 
{
 Write-Host `n "Shared channel summary report available in: " -NoNewline -ForegroundColor Yellow; Write-Host "$OutputCSVName"`n 
 Write-Host `n "Detailed shared channel membership report available in: " -NoNewline -ForegroundColor Yellow; Write-Host "$OutputCSV"`n 
 $Prompt = New-Object -ComObject wscript.shell   
 $UserInput = $Prompt.popup("Do you want to open output file?",`   
 0,"Open Output File",4)   
 If ($UserInput -eq 6)   
 {   
  Invoke-Item "$OutputCSVName"
  Invoke-Item "$OutputCSV"   
 } 
Write-Host `n~~ Script prepared by AdminDroid Community ~~`n -ForegroundColor Green
Write-Host "~~ Check out " -NoNewline -ForegroundColor Green; Write-Host "admindroid.com" -ForegroundColor Yellow -NoNewline; Write-Host " to get access to 1800+ Microsoft 365 reports. ~~" -ForegroundColor Green `n`n
}