import os
import subprocess

def ghdlEnvExists(relativePath="work"):
    ## Check if work exists
    try:
        os.lstat(relativePath)
    except:
        return False
    ## Check that work is writable
    if not os.access(relativePath, os.W_OK):
        print(f"{relativePath} is write-protected, please acquire correct permissions")
        return False
    cfFileExists = False
    filesInWork = os.listdir(relativePath)
    for file in filesInWork:
        if ".cf" in file:
            cfFileExists = True
    if not cfFileExists:
        return False
    ## Nothing bad, continue
    return True

def createBuildEnv():
    if ghdlEnvExists():
       return -1
    ## Create build env
    os.makedirs("work",exist_ok=True)
    addAllVHDLFiles(init=True)
    return 0

def addAllVHDLFiles(init=False):
    ## Ensure everything is ready for adding files 
    ## (init exception to avoid one if-case in ghdlEnvExists)
    if not ghdlEnvExists() and not init:
       return -1
    ## Add files
    vhdlFiles = []
    for file in os.listdir():
        if ".vhd" in file:
            vhdlFiles.append(file)
    command = ["ghdl", "-i", "--workdir=work"] + vhdlFiles
    subprocess.run(command)
    return 0


if __name__ == "__main__":
    createBuildEnv()