param(
  [String]$COMPort,
  [switch]$Extras,
  [switch]$ResetAfterFlash,
  [switch]$WriteMicropython,
  [ValidateSet("ESP32","ESP8266","ESP8285","PYBv1.0","PYBv1.1","PYBLite","PYBv3")]
    [string]$BoardType,
  [switch]$Verbose,
  [String[]]$Libs
)
<#
Supported board types (at time of writing) for MicroPython are:
- esp32, esp8266 (and esp8285 by extension)
- stm32, teensy
- CC3200
Boards themselves:
STM32-
- pyBoard (v1.0, v1.1, Lite, v3) and chinese clones of pyBoard (uses v3 layout)
- Espruino Pico
- Olimex STM32 405STK, E407, H405, H407, P407
- ST Micro Discovery STM32F401, F407, F429, F746
- Teensy 3.1, 3.5, 3.6
Not going to list supported Espressif ESP8266, ESP8285 and ESP32 boards because the list is endless.
#>

#TODO Get-MicroPythonFirmware {}
######## Download latest firmware from website or whatever
#TODO Write-MicroPythonFirmware {}
######## esptool(.py)? erase_flash, then write_flash - erase_flash only needed if it's a fresh install
#TODO Update-uPyConfig {} - to dynamically generate a board config from PS values
######## uPyConfig.py will contain template values and will become uPyConfig.tpl

Function Find-SerialPort {
    param (
        [switch]$DeviceNameOnly,
        [switch]$First
    )
    #On OSX, all serial devices are created with both a cu. and tty. file
    # "cu" is "Call-Up", where we initiate the connection to the device
    # "tty" is "Totally Terminal, Yeah", where the device initiates the connection
    #On Linux, all serial devices have one device file. While simpler, this means
    # more work is needed in order to determine what serial devices are present.
    # Possible way of determining is to see if the owning group is 'dialout'?
    #On Windows, all serial devices are registered with COM ports.

    #On Windows, if running Windows PowerShell rather than pwsh, $IsWindows will be undefined
    # but we can safely assume that $IsWindows being null categorically means we're on windows
    # because Microsoft have never released Windows PowerShell on anything other than windows.
    #Remember the distinction between Windows PowerShell and the open-source PowerShell (pwsh)
    If ($IsWindows -or $IsWindows -eq $Null) {
        $Devices=change.exe port /query | ? { $_ -notlike '*DosDevices*' }
        $Devices=($Devices|%{$device=$_ -split ' = ';[PSCustomObject]@{
            Name = $device[0]
            File = $device[1]
        }})
    } ElseIf ($IsMacOS) {
        $Devices=Get-ChildItem -Path /dev -Filter 'cu.*' | ? { $_.Name -notlike '*Bluetooth*' }
        $Devices=@($Devices|%{[PSCustomObject]@{
            Name = $_.Name
            File = ($_|Convert-Path)
        }})
    } ElseIf ($IsLinux) {
        $Devices=Get-ChildItem -Path /dev -File | ? { (stat -c '%G' ($_|Convert-Path)) -ieq 'dialout' }
        $Devices=@($Devices|%{[PSCustomObject]@{
            Name = $_.Name
            File = ($_|Convert-Path)
        }})
    } Else {
        #Sorry FreeBSD
        Write-Error -Message "OS currently unsupported for this function" -ErrorAction Stop
    }
    If ($Devices.Count -eq 0) {
        Write-Error -Message "No serial ports found on system" -ErrorAction Stop
    }
    If ($First) {
        If ($DeviceNameOnly) {
            $Devices[0].Name
        } Else {
            $Devices[0]
        }
    } Else {
        If ($DeviceNameOnly) {
            $Devices | % { $_.Name }
        } Else {
            $Devices
        }
    }
}

Function Find-LibraryFile {
  [cmdletbinding()]
  param(
    [String]$Library,
    [String]$SearchPath = $(Get-Location)
  )
  return (Get-ChildItem -Path $SearchPath -Recurse -Verbose:$Verbose -Name "$Library.py"|Convert-Path -Verbose:$Verbose)
}

Function Write-AmpyFile {
  [cmdletbinding()]
  param(
    [String]$Filename,
    [String]$COMPort
  )
  If ((Get-Command -Name ampy -ErrorAction SilentlyContinue) -eq $false) {
    Write-Error -Message "Couldn't locate ``ampy`` in environment paths - please run ``pip install adafruit-ampy``." -ErrorAction Stop
  }
  Write-Verbose "Writing $Filename to port $COMPort" -Verbose:$Verbose
  ampy -p $COMPort put $Filename
}

Function Reset-AmpyDevice {
  [cmdletbinding()]
  param(
    [String]$COMPort
  )
  If ((Get-Command -Name ampy -ErrorAction SilentlyContinue) -eq $false) {
    Write-Error -Message "Couldn't locate ``ampy`` in environment paths - please run ``pip install adafruit-ampy``." -ErrorAction Stop
  }
  Write-Verbose "Resetting port $COMPort" -Verbose:$Verbose
  ampy -p $COMPort reset
}

$BaseFiles = (
  'boot',
  'main',
  'uPyConfig'
)
$ExtraFiles = (
  'init_sample'
)
$CfgFiles = (
  'wifi_cfg',
  'webrepl_cfg'
)

$BaseFiles | % {
  $Lib = Find-LibraryFile -Library $_ -Verbose:$Verbose
  Write-AmpyFile -Filename "$Lib" -COMPort $COMPort -Verbose:$Verbose
}
$CfgFiles | % {
  If (Get-ChildItem "$_.py" -ErrorAction SilentlyContinue) {
    Write-AmpyFile -Filename "$_.py" -COMPort $COMPort -Verbose:$Verbose
  }
}
If ($Extras) {
  $ExtraFiles | % {
    $Lib = Find-LibraryFile -Library $_ -Verbose:$Verbose
    Write-AmpyFile -Filename "$Lib" -COMPort $COMPort -Verbose:$Verbose
  }
}
If ($Libs.Count -gt 0) {
  $Libs | % {
    $Lib = Find-LibraryFile -Library $_ -Verbose:$Verbose
    Write-AmpyFile -Filename "$Lib" -COMPort $COMPort -Verbose:$Verbose
  }
}
If ($ResetAfterFlash) { Reset-AmpyDevice -COMPort $COMPort -Verbose:$Verbose }