#!powershell
# This file is part of Ansible
#
# Copyright 2015, George Frank <george@georgefrank.net>
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.

$ErrorActionPreference = "Stop"

# WANT_JSON
# POWERSHELL_COMMON

$params = Parse-Args $args;
$result = New-Object PSObject;
Set-Attr $result "changed" $false;


If ($params.name)
{
    $name = $params.name
}
Else
{
    Fail-Json $result "missing required argument: name"
}

If ($params.state)
{
    $state = $params.state.ToString().ToLower()
    $validStates = "present", "absent", "started", "stopped", "restarted"

    If ($validStates -notcontains $state)
    {
        Fail-Json $result "state is $state; must be one of: $validStates"
    }
}
else
{
    $state = "present"
}

If ($params.application)
{
    $application = $params.application
}
Else
{
    $application = $null
}

If ($params.app_parameters)
{
    $appParameters = $params.app_parameters
}
Else
{
    $appParameters = $null
}

If ($params.stdout_file)
{
    $stdoutFile = $params.stdout_file
}
Else
{
    $stdoutFile = $null
}

If ($params.stderr_file)
{
    $stderrFile = $params.stderr_file
}
Else
{
    $stderrFile = $null
}

Function Service-Exists
{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$name
    )

    return [bool](Get-Service "$name" -ErrorAction SilentlyContinue)
}

Function Nssm-Remove
{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$name
    )

    if (Service-Exists -name $name)
    {
        $cmd = "nssm stop ""$name"""
        $results = invoke-expression $cmd

        $cmd = "nssm remove ""$name"" confirm"
        $results = invoke-expression $cmd

        if ($LastExitCode -ne 0)
        {
            Set-Attr $result "nssm_error_cmd" $cmd
            Set-Attr $result "nssm_error_log" "$results"
            Throw "Error removing service ""$name"""
        }

        $result.changed = $true
     }
}

Function Nssm-Install
{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$name,
        [Parameter(Mandatory=$true)]
        [string]$application
    )

    if (!$application)
    {
        Throw "Error installing service ""$name"". No application was supplied."
    }

    if (!(Service-Exists -name $name))
    {
        $cmd = "nssm install ""$name"" $application"

        $results = invoke-expression $cmd

        if ($LastExitCode -ne 0)
        {
            Set-Attr $result "nssm_error_cmd" $cmd
            Set-Attr $result "nssm_error_log" "$results"
            Throw "Error installing service ""$name"""
        }

        $result.changed = $true
        
     } else {
        $cmd = "nssm get ""$name"" Application"
        $results = invoke-expression $cmd

        if ($LastExitCode -ne 0)
        {
            Set-Attr $result "nssm_error_cmd" $cmd
            Set-Attr $result "nssm_error_log" "$results"
            Throw "Error installing service ""$name"""
        }

        if ($results -ne $application)
        {
            $cmd = "nssm set ""$name"" Application $application"

            $results = invoke-expression $cmd

            if ($LastExitCode -ne 0)
            {
                Set-Attr $result "nssm_error_cmd" $cmd
                Set-Attr $result "nssm_error_log" "$results"
                Throw "Error installing service ""$name"""
            }

            $result.changed = $true
        }
     }
}

Function ParseAppParameters()
{
   [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$appParameters
    )

    return ConvertFrom-StringData -StringData $appParameters.TrimStart("@").TrimStart("{").TrimEnd("}").Replace("; ","`n")
}


Function Nssm-Update-AppParameters
{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$name,
        [Parameter(Mandatory=$true)]
        [string]$appParameters
    )

    $cmd = "nssm get ""$name"" AppParameters"
    $results = invoke-expression $cmd

    if ($LastExitCode -ne 0)
    {
        Set-Attr $result "nssm_error_cmd" $cmd
        Set-Attr $result "nssm_error_log" "$results"
        Throw "Error updating AppParameters for service ""$name"""
    }

    $appParametersHash = ParseAppParameters -appParameters $appParameters

    $appParamKeys = @()
    $appParamVals = @()
    $singleLineParams = ""
    $appParametersHash.GetEnumerator() |
        % {
            $key = $($_.Name)
            $val = $($_.Value)

            $appParamKeys += $key
            $appParamVals += $val

            if ($key -eq "_") {
                $singleLineParams = "$val " + $singleLineParams
            } else {
                $singleLineParams = $singleLineParams + "$key ""$val"""
            }
        }

    Set-Attr $result "nssm_app_parameters" $appParameters
    Set-Attr $result "nssm_app_parameters_parsed" $appParametersHash
    Set-Attr $result "nssm_app_parameters_keys" $appParamKeys
    Set-Attr $result "nssm_app_parameters_vals" $appParamVals
    Set-Attr $result "nssm_single_line_app_parameters" $singleLineParams

    if ($results -ne $singleLineParams)
    {
        $cmd = "nssm set ""$name"" AppParameters $singleLineParams"
        $results = invoke-expression $cmd

        if ($LastExitCode -ne 0)
        {
            Set-Attr $result "nssm_error_cmd" $cmd
            Set-Attr $result "nssm_error_log" "$results"
            Throw "Error updating AppParameters for service ""$name"""
        }

        $result.changed = $true
    }
}

Function Nssm-Set-Ouput-Files
{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$name,
        [string]$stdout,
        [string]$stderr
    )

    $cmd = "nssm get ""$name"" AppStdout"
    $results = invoke-expression $cmd

    if ($LastExitCode -ne 0)
    {
        Set-Attr $result "nssm_error_cmd" $cmd
        Set-Attr $result "nssm_error_log" "$results"
        Throw "Error retrieving existing stdout file for service ""$name"""
    }

    if ($results -ne $stdout)
    {
        if (!$stdout)
        {
            $cmd = "nssm reset ""$name"" AppStdout"
        } else {
            $cmd = "nssm set ""$name"" AppStdout $stdout"        
        }
    
        $results = invoke-expression $cmd

        if ($LastExitCode -ne 0)
        {
            Set-Attr $result "nssm_error_cmd" $cmd
            Set-Attr $result "nssm_error_log" "$results"
            Throw "Error setting stdout file for service ""$name"""
        }

        $result.changed = $true
    }

    $cmd = "nssm get ""$name"" AppStderr"
    $results = invoke-expression $cmd

    if ($LastExitCode -ne 0)
    {
        Set-Attr $result "nssm_error_cmd" $cmd
        Set-Attr $result "nssm_error_log" "$results"
        Throw "Error retrieving existing stderr file for service ""$name"""
    }

    if ($results -ne $stderr)
    {
        if (!$stderr)
        {
            $cmd = "nssm reset ""$name"" AppStderr"
            $results = invoke-expression $cmd

            if ($LastExitCode -ne 0)
            {
                Set-Attr $result "nssm_error_cmd" $cmd
                Set-Attr $result "nssm_error_log" "$results"
                Throw "Error clearing stderr file setting for service ""$name"""
            }
        } else {
            $cmd = "nssm set ""$name"" AppStderr $stderr"
            $results = invoke-expression $cmd

            if ($LastExitCode -ne 0)
            {
                Set-Attr $result "nssm_error_cmd" $cmd
                Set-Attr $result "nssm_error_log" "$results"
                Throw "Error setting stderr file for service ""$name"""
            }
        }

        $result.changed = $true
    }

    ###
    # Setup file rotation so we don't accidentally consume too much disk
    ###

    #set files to overwrite
    $cmd = "nssm set ""$name"" AppStdoutCreationDisposition 2"
    $results = invoke-expression $cmd

    $cmd = "nssm set ""$name"" AppStderrCreationDisposition 2"
    $results = invoke-expression $cmd

    #enable file rotation
    $cmd = "nssm set ""$name"" AppRotateFiles 1"
    $results = invoke-expression $cmd

    #don't rotate until the service restarts
    $cmd = "nssm set ""$name"" AppRotateOnline 0"
    $results = invoke-expression $cmd

    #both of the below conditions must be met before rotation will happen
    #minimum age before rotating
    $cmd = "nssm set ""$name"" AppRotateSeconds 86400"
    $results = invoke-expression $cmd

    #minimum size before rotating
    $cmd = "nssm set ""$name"" AppRotateBytes 104858"
    $results = invoke-expression $cmd
}

Function Nssm-Get-Status
{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$name
    )

    $cmd = "nssm status ""$name"""
    $results = invoke-expression $cmd

    return ,$results
}

Function Nssm-Start
{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$name
    )

    $currentStatus = Nssm-Get-Status -name $name

    if ($LastExitCode -ne 0)
    {
        Set-Attr $result "nssm_error_cmd" $cmd
        Set-Attr $result "nssm_error_log" "$results"
        Throw "Error starting service ""$name"""
    }

    switch ($currentStatus)
    {
        "SERVICE_RUNNING" { <# Nothing to do #> }
        "SERVICE_STOPPED" { Nssm-Start-Service-Command -name $name }
        
        "SERVICE_CONTINUE_PENDING" { Nssm-Stop-Service-Command -name $name; Nssm-Start-Service-Command -name $name }
        "SERVICE_PAUSE_PENDING" { Nssm-Stop-Service-Command -name $name; Nssm-Start-Service-Command -name $name }
        "SERVICE_PAUSED" { Nssm-Stop-Service-Command -name $name; Nssm-Start-Service-Command -name $name }
        "SERVICE_START_PENDING" { Nssm-Stop-Service-Command -name $name; Nssm-Start-Service-Command -name $name }
        "SERVICE_STOP_PENDING" { Nssm-Stop-Service-Command -name $name; Nssm-Start-Service-Command -name $name }
    }
}

Function Nssm-Start-Service-Command
{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$name
    )

    $cmd = "nssm start ""$name"""

    $results = invoke-expression $cmd

    if ($LastExitCode -ne 0)
    {
        Set-Attr $result "nssm_error_cmd" $cmd
        Set-Attr $result "nssm_error_log" "$results"
        Throw "Error starting service ""$name"""
    }

    $result.changed = $true
}

Function Nssm-Stop-Service-Command
{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$name
    )

    $cmd = "nssm stop ""$name"""

    $results = invoke-expression $cmd

    if ($LastExitCode -ne 0)
    {
        Set-Attr $result "nssm_error_cmd" $cmd
        Set-Attr $result "nssm_error_log" "$results"
        Throw "Error stopping service ""$name"""
    }

    $result.changed = $true
}

Function Nssm-Stop
{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$name
    )

    $currentStatus = Nssm-Get-Status -name $name

    if ($LastExitCode -ne 0)
    {
        Set-Attr $result "nssm_error_cmd" $cmd
        Set-Attr $result "nssm_error_log" "$results"
        Throw "Error stopping service ""$name"""
    }

    if (currentStatus -ne "SERVICE_STOPPED")
    {
        $cmd = "nssm stop ""$name"""

        $results = invoke-expression $cmd

        if ($LastExitCode -ne 0)
        {
            Set-Attr $result "nssm_error_cmd" $cmd
            Set-Attr $result "nssm_error_log" "$results"
            Throw "Error stopping service ""$name"""
        }

        $result.changed = $true
    }
}

Function Nssm-Restart
{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]$name
    )

    Nssm-Stop-Service-Command -name $name
    Nssm-Start-Service-Command -name $name
}

Try
{
    switch ($state)
    {
        "absent" { Nssm-Remove -name $name }
        "present" {
            Nssm-Install -name $name -application $application
            Nssm-Update-AppParameters -name $name -appParameters $appParameters
            Nssm-Set-Ouput-Files -name $name -stdout $stdoutFile -stderr $stderrFile
        }
        "started" {
            Nssm-Install -name $name -application $application
            Nssm-Update-AppParameters -name $name -appParameters $appParameters
            Nssm-Set-Ouput-Files -name $name -stdout $stdoutFile -stderr $stderrFile
            Nssm-Start -name $name
        }
        "stopped" {
            Nssm-Install -name $name -application $application
            Nssm-Update-AppParameters -name $name -appParameters $appParameters
            Nssm-Set-Ouput-Files -name $name -stdout $stdoutFile -stderr $stderrFile
            Nssm-Stop -name $name
        }
        "restarted" {
            Nssm-Install -name $name -application $application
            Nssm-Update-AppParameters -name $name -appParameters $appParameters
            Nssm-Set-Ouput-Files -name $name -stdout $stdoutFile -stderr $stderrFile
            Nssm-Restart -name $name
        }
    }

    Exit-Json $result;
}
Catch
{
     Fail-Json $result $_.Exception.Message
}