### Workspace ###
$workspaceSettings = "$env:USERPROFILE\.pwsh_workspace_settings.txt"
$activeWorkspace = ""

# Check that the workspace settings file exists
function Test-Workspace-Settings {
    $result = Test-Path -Path $global:workspaceSettings
    return $result
}

# If the alias exists, returns the path of the workspace
function Test-Workspace-Alias {
    param([Parameter(Mandatory=$true)]
          [string]$Alias)

    $result = ""
    if(Test-Workspace-Settings) {
        $workspaceData = Get-Content $global:workspaceSettings
        foreach($entry in $workspaceData) {
            $parts = $entry -split ","
            if($parts.Length -eq 2) {
                if($parts[0] -eq $Alias) {
                    $result = $parts[1]
                    break;
                }
            }
            else {
                Write-Host "Expecting workspace entry to have two parts, it has $parts.Length"
            }
        }
    }

    return $result
}

# Check that an active workspace has been set
function Test-Active-Workspace {
    return Test-Path -path $global:activeWorkspace
}

# Add a new workspace to workspace settings
# Name is required
# If no path is given, current working directory is used
function Add-Workspace {
    param([Parameter(Mandatory=$true)]
          [string]$Name,
          [Parameter(Mandatory=$false)]
          [string]$Path)

    if(-Not $Path) {
        $Path = Get-Location
    }

    if(Test-Path -Path $Path) {
        $workspaceSettings = Test-Workspace-Settings
        $workspaceEntry = "{0},{1}" -f $Name, $Path
        if($workspaceSettings) {
            if(Test-Workspace-Alias -Alias $Name) {
                Write-Host "Alias already exists: $Name"
            }
            else {
                Add-Content -Path $global:workspaceSettings -Value $workspaceEntry
                Show-Workspace-Settings
            }
        }
        else {
            # just write out to the file
            Set-Content -Path $global:workspaceSettings -Value $workspaceEntry
            Show-Workspace-Settings
        }
    }
    else {
        Write-Output "$Path does not exist, cannot create workspace"
    }
}

# Set the active workspace using workspace alias
# Will look in workspace settings to see if there is an entry
# matching the provided alias, if so, will set active workspace path
# to the path found in workspace settings
function Set-Workspace {
    param([Parameter(Mandatory=$true)]
          [string]$Name)

    $result = Test-Workspace-Alias -Alias $Name
    if($result) {
        if(Test-Path -Path $result) {
            Write-Host "Setting active workspace to: $result"
            $global:activeWorkspace = $result
        }
        else {
            Write-Host "Workspace path $result does not exist"
        }
    }
    else {
        Write-Host "Workspace alias $Name not found"
    }
    return $result
}

# Open the workspace settings file in notepad
function Open-Workspace-Settings {
    if(Test-Workspace-Settings) {
        Start-Process notepad.exe $global:workspaceSettings
    }
}

# Delete workspace settings file
function Remove-Workspace-Settings {
    if(Test-Workspace-Settings) {
        Remove-Item -Path $global:workspaceSettings
    }
}

# Remove a workspace by name
# Checks workspace settings to see if there is an entry with
# the provided name. Removes the entry if it exists.
function Remove-Workspace {
    param([Parameter(Mandatory=$true)]
          [string]$Name)

    $existing = @()
    if(Test-Workspace-Settings) {
        $workspaceData = Get-Content $global:workspaceSettings
        # rebuild the workspace settings contents and leave out
        # an entry if it matches the incoming $Name
        foreach($entry in $workspaceData) {
            $parts = $entry -split ","
            if($parts.Length -eq 2) {
                if($parts[0] -ne $Name) {
                    $existing += $entry
                }
            }
            else {
                Write-Host "Expecting workspace entry to have two parts, it has $parts.Length"
            }
        }

        if($existing.Length -gt 0) {
            # clear the file contents
            $existing | Set-Content -Path $global:workspaceSettings
        }

        Show-Workspace-Settings
    }
}

# Print the contents of the workspace settings file to console
function Show-Workspace-Settings {
    if(Test-Workspace-Settings) {
        $workspaceData = Get-Content $global:workspaceSettings
        foreach($entry in $workspaceData) {
            $parts = $entry -split ","
            if($parts.Length -eq 2) {
                $showString = "Alias: {0}, Path: {1}" -f $parts[0], $parts[1]
                Write-Host $showString
            }
            else {
                Write-Host "Incorrect workspace entry, cannot parse alias and path: $entry"
            }
        }
    }
}

# Open the active workspace in file explorer
function Open-Active-Workspace {
    if(Test-Active-Workspace) {
        Write-Host "Opening workspace: $global:activeWorkspace"
        Start-Process explorer.exe $global:activeWorkspace
    }
    else {
        Write-Host "Active workspace not set or not valid path"
    }
}

# Look up workspace path by name, if found set it to active workspace
# and navigate to the workspace path
function Use-Workspace {
    param([Parameter(Mandatory=$true)]
          [string]$Name)

    if(Set-Workspace -Name $Name) {
        Write-Host "Changing to workspace: $global:activeWorkspace"
        Set-Location $global:activeWorkspace
    }
}
### end workspace ###

#### ushell ####

# Expects that Set-Workspace has been called
# Navigate to the active workspace path and attemp to load ushell
# For ushell import to work correctly, workspace path is expected
# to be something like C:\<top_level>\UE
function Use-Active-UE-Workspace {
    if(Test-Active-Workspace) {
        Write-Host "Changing to workspace: $global:activeWorkspace"
        Set-Location $global:activeWorkspace

        $ushellRelativePath = "Engine\Extras\ushell\ushell.psm1"
        $ushellPath = "{0}\{1}" -f $global:activeWorkspace, $ushellRelativePath
        Write-Host "Checking for ushell at: $ushellPath"
        if(Test-Path -Path $ushellPath) {
            Import-Module -Name $ushellPath
        }
        else {
            Write-Host "Unable to import ushell -- is workspace an Unreal project?"
        }
    }
    else {
        Write-Host "No active workspace to use"
    }
}

# Creates a new powershell session then navigates to the
# workspace path and imports the ushell module. Creating a
# new session is needed so that when you switch UE workspaces,
# ushell is installed with the correct context of the workspace.
function Use-UE-Workspace {
    param([Parameter(Mandatory=$true)]
          [string]$Name,
          [Parameter(Mandatory=$false)]
          [bool]$NewSession = $true)

    if($NewSession) {
        New-UE-Session -Name $Name
    }
    else {
        Use-Workspace -Name $Name
        $location = Get-Location

        $resolvedCurrentLocation = Resolve-Path $location
        $resolvedActiveWorkspace = Resolve-Path $global:activeWorkspace
        # Check that we are in the expected place then proceed
        if($resolvedCurrentLocation.ProviderPath -eq $resolvedActiveWorkspace.ProviderPath) {
            if(Test-Active-Workspace) {
                $ushellRelativePath = "Engine\Extras\ushell\ushell.psm1"
                $ushellPath = "{0}\{1}" -f $resolvedActiveWorkspace, $ushellRelativePath
                Write-Host "Checking for ushell at: $ushellPath"
                if(Test-Path -Path $ushellPath) {
                    Import-Module -Name $ushellPath
                }
                else {
                    Write-Host "Unable to import ushell -- is workspace an Unreal project?"
                }
            }
        }
        else {
            Write-Error "Did not correctly switch to workspace $Name"
        }
    }
}

function New-UE-Session {
    param([Parameter(Mandatory=$true)]
          [string]$Name)
    if(Test-Workspace-Alias -Alias $Name) {
        Start-Process pwsh -ArgumentList @("-NoExit", "-Command", "& {. $PROFILE; Use-UE-Workspace -Name $Name -NewSession `$false`}")
        Stop-Process -Id $PID
    }
    else {
        Write-Host "Alias $Name does not exist, not creating new session"
    }
}
### Workspace ###