colours.py

#!/usr/bin/python3

# Colours module by Karim Sultan April 2015.

# Version KAS 150412
# This script defines a set of constants for foreground colors,
# background colors, and console text styles to be used in Python
# console scripts.
#
# KSU 201010 Added macro modes + test case.
# KSU 210301 Added an ANSI enabled test for NT.  This is useful for NT if ANSI is enabled in a
#            console terminal window.
#            To enable ANSI in PowerShell under Windows 10, and Server 2012+:
#            > Set-ItemProperty HKCU:\Console VirtualTerminalLevel -Type DWORD 1
# https://stackoverflow.com/questions/51680709/colored-text-output-in-powershell-console-using-ansi-vt100-codes
#
# NOTE: Windows defaults to ANSI Colour OFF.  This module will attempt to check if NT's 
# HKCU::\Console\VirtualTerminalLevel is set to 1; if so it will enable colours on NT; if not, it will
# disable them. This is for cross-platform portability.

#
# To use this script in python:
#
# In your python script, near the top, add:
# import colour
#
# Example:
# s = Col.cdr + "Warning!" + Col.coff
# s = Col.sre + Col.cly + Col.bdr + "Error! Error!" + Col.soff + Col.coff + Col.boff
#
# Use the Color Off constant "coff", the Background Color Off
# constant "boff" and the Style Off constant "soff" to clear
# formatting:
# s = Col.coff + Col.soff + Col.boff +"Back to normal"
#
# Codes are abbreviated for quick insertion.  Abbreviation format:
# 1st:   c: color         b: background color           s: style
# 2nd:   l: light         d: dark
# rest:  color / style
import winreg
import os

# Under Windows, checks for a registry key that indicates ANSI codes
# are accepted.
def isWinAnsiEnabled():
   try:
      Registry=winreg.ConnectRegistry(None, winreg.HKEY_CURRENT_USER)
      Key=winreg.OpenKeyEx(Registry, "Console")
      vtup=winreg.QueryValueEx(Key, "VirtualTerminalLevel")
      if (vtup[0]==1):
         return True
      else:
         return False
   except e:
      # Key does not exist
      return False


class Colours:

   # No support for ANSI in Windows, so disable.
   if (os.name=="Windows" or os.name=="nt") and (not isWinAnsiEnabled()):
      # Foreground (Text) Colors
      cbl=""       # Color Black
      cdr=""       # Color Dark Red
      cdg=""       # Color Dark Green
      cdy=""       # Color Dark Yellow
      cdb=""       # Color Dark Blue
      cdm=""       # Color Dark Magenta
      cdc=""       # Color Dark Cyan
      cdgy=""      # Color Dark Gray

      clgy=""      # Color Light Gray
      clr=""       # Color Light Red
      clg=""       # Color Light Green
      cly=""       # Color Light Yellow
      clb=""       # Color Light Blue
      clm=""       # Color Light Magenta
      clc=""       # Color Light Cyan
      cwh=""       # Color White

      # Turns off all formatting
      coff=""       # Color Off

      # Background Colors
      bbl=""       # Background Color Black
      bdr=""       # Background Color Dark Red
      bdg=""       # Background Color Dark Green
      bdy=""       # Background Color Dark Yellow
      bdb=""       # Background Color Dark Blue
      bdm=""       # Background Color Dark Magenta
      bdc=""       # Background Color Dark Cyan
      bdgy=""     # Background Color Dark Gray

      blgy=""      # Background Color Light Gray
      blr=""      # Background Color Light Red
      blg=""      # Background Color Light Green
      bly=""      # Background Color Light Yellow
      blb=""      # Background Color Light Blue
      blm=""      # Background Color Light Magenta
      blc=""      # Background Color Light Cyan
      bwh=""      # Background Color White

      # Turns off only the background color
      boff=""      # Background Color Off

      # Macro strings 
      # Master off switch turns off color and bacground in one mnemonic
      off=coff+boff
      no=cly+bdr
      yes=clg+bdg
      old=cly+bdb
      retro=cwh+bbl
      paper=cbl+bwh

      # Styles
      sbo=""        # Style Bold
      sdi=""        # Style Dim
      sun=""        # Style Underline
      sbl=""        # Style Blink
      sre=""        # Style Reverse
      shi=""        # Style Hidden

      sbof=""      # Style Bold Off
      sdif=""      # Style Dim Off
      sunf=""      # Style Underline Off
      sblf=""      # Style Blink Off
      sref=""      # Style Reverse Off
      shif=""      # Style Hidden Off

   # Linux supports ANSI
   else:
      # Foreground (Text) Colors
      cbl="\033[30m"       # Color Black
      cdr="\033[31m"       # Color Dark Red
      cdg="\033[32m"       # Color Dark Green
      cdy="\033[33m"       # Color Dark Yellow
      cdb="\033[34m"       # Color Dark Blue
      cdm="\033[35m"       # Color Dark Magenta
      cdc="\033[36m"       # Color Dark Cyan
      cdgy="\033[90m"      # Color Dark Gray

      clgy="\033[37m"      # Color Light Gray
      clr="\033[91m"       # Color Light Red
      clg="\033[92m"       # Color Light Green
      cly="\033[93m"       # Color Light Yellow
      clb="\033[94m"       # Color Light Blue
      clm="\033[95m"       # Color Light Magenta
      clc="\033[96m"       # Color Light Cyan
      cwh="\033[97m"       # Color White

      # Turns off all formatting
      coff="\033[0m"       # Color Off

      # Background Colors
      bbl="\033[40m"       # Background Color Black
      bdr="\033[41m"       # Background Color Dark Red
      bdg="\033[42m"       # Background Color Dark Green
      bdy="\033[43m"       # Background Color Dark Yellow
      bdb="\033[44m"       # Background Color Dark Blue
      bdm="\033[45m"       # Background Color Dark Magenta
      bdc="\033[46m"       # Background Color Dark Cyan
      bdgy="\033[100m"     # Background Color Dark Gray

      blgy="\033[47m"      # Background Color Light Gray
      blr="\033[101m"      # Background Color Light Red
      blg="\033[102m"      # Background Color Light Green
      bly="\033[103m"      # Background Color Light Yellow
      blb="\033[104m"      # Background Color Light Blue
      blm="\033[105m"      # Background Color Light Magenta
      blc="\033[106m"      # Background Color Light Cyan
      bwh="\033[107m"      # Background Color White

      # Turns off only the background color
      boff="\033[49m"      # Background Color Off

      # Macro strings
      # Master off switch turns off color and bacground in one mnemonic
      off=coff+boff
      no=cly+bdr
      yes=clg+bdg
      old=cly+bdb
      retro=cwh+bbl
      paper=cbl+bwh

      # Styles
      sbo="\033[1m"        # Style Bold
      sdi="\033[2m"        # Style Dim
      sun="\033[4m"        # Style Underline
      sbl="\033[5m"        # Style Blink
      sre="\033[7m"        # Style Reverse
      shi="\033[8m"        # Style Hidden

      sbof="\033[21m"      # Style Bold Off
      sdif="\033[22m"      # Style Dim Off
      sunf="\033[24m"      # Style Underline Off
      sblf="\033[25m"      # Style Blink Off
      sref="\033[27m"      # Style Reverse Off
      shif="\033[28m"      # Style Hidden Off

   # Lists of colour and backgrounds
   cnames = ["cbl", "cdr", "cdg", "cdy", "cdb", "cdm", "cdc", "cdgy",
             "clgy","clr", "clg", "cly", "clb", "clm", "clc", "cwh"]

   bnames = ["bbl", "bdr", "bdg", "bdy", "bdb", "bdm", "bdc", "bdgy",
             "blgy","blr", "blg", "bly", "blb", "blm", "blc", "bwh"]

   listcall = [f"{cbl}", f"{cdr}", f"{cdg}", f"{cdy}", f"{cdb}", f"{cdm}", f"{cdc}", f"{cdgy}",
   f"{clgy}", f"{clr}", f"{clg}", f"{cly}", f"{clb}", f"{clm}", f"{clc}", f"{cwh}", f"{coff}"]

   listball = [f"{bbl}", f"{bdr}", f"{bdg}", f"{bdy}", f"{bdb}", f"{bdm}", f"{bdc}", f"{bdgy}",
   f"{blgy}", f"{blr}", f"{blg}", f"{bly}", f"{blb}", f"{blm}", f"{blc}", f"{bwh}", f"{boff}"]

   listsall = [f"{sbo}", f"{sdi}", f"{sun}", f"{sbl}", f"{sre}", f"{shi}",
   f"{sbof}", f"{sdif}", f"{sunf}", f"{sblf}", f"{sref}", f"{shif}"]

   listmall = [f"'NO': {no}", f"'YES': {yes}", f"'OLD': {old}", f"'RETRO': {retro}", f"'PAPER': {paper}", f"{off}"]

   # Static method to remove colour codes from a formatted string
   # This could probably be done more compactly with a regex, but this way
   # was super quick and easy.  :)
   @staticmethod
   def cstrip(label):
      for c in Colours.listcall:
         label=label.replace(c, "")
      for b in Colours.listball:
         label=label.replace(b, "")
      for s in Colours.listsall:
         label=label.replace(s, "")
      return (label)

#End of class
#**************************************************************************

def makeColourGrid():
   print(f"{Colours.sre}Colour grid:{Colours.sref}")
   print("     ", end='')
   for i in range (16):
      print(f"{Colours.bnames[i]:^5}", end='')
   print()
   x=0
   for c in Colours.listcall:
      if not c==Colours.coff:
         print (f"{Colours.cnames[x]:^5}", end='')
         x+=1
      for b in Colours.listball:
         if not c==Colours.coff and not b==Colours.boff:
            print (f"{c}{b}  W  {Colours.off}", end='', flush=True)
      print()
   print()

# Test method.  No need for unit tests with this Class; just illustrate the 
# colours.
def doTest():
   C = Colours()
   if (C.clc==""):
      print ("This OS does not support ANSI colour in terminals.")
      print ("Test will execute, but output should be colourless.")
      print ("Note that you can enable ANSI colours in Windows PowerShell with:")
      print ()
      print ("> Set-ItemProperty HKCU:\Console VirtualTerminalLevel -Type DWORD 1")
      print ()
      print ("(and then close/reopen your console, PowerShell or DOS window)")
      print ()

   print()
   print (f"{C.sre}Foreground Colour Test:{C.sref} ", end='')
   for c in C.listcall:
      if not c==C.coff:
         print (f"{c}W{C.coff}", end='', flush=True)
   print()

   print (f"{C.sre}Background Colour Test:{C.sref} ", end='')
   for b in C.listball:
      if not b==C.boff:
         print (f"{b}W{C.boff}", end='', flush=True)
   print()

   print()
   print (f"{C.sre}Macro format tests:{C.sref}")
   for m in C.listmall:
      if not m==C.off:
         print (f"{m}Colours Module is colourful.{C.off}")
   print()

   print(f"{C.sre}Style test:{C.sref} (Note not all styles work on all terminals){C.clc}")
   print(f"{C.sbo}This is BOLD.{C.sbof}")
   print(f"{C.sdi}This is DIM.{C.sdif}")
   print(f"{C.sun}This is UNDERLINE.{C.sunf}")
   print(f"{C.sre}This is REVERSE.{C.sref}")
   print(f"{C.sbl}This is BLINK.{C.sblf}")
   print(f"{C.shi}This is HIDDEN.{C.shif}{C.off}")

   print()
   makeColourGrid()

if (__name__=="__main__"):
   doTest()