# SPDX-License-Identifier: GPL-2.0-or-later
#
# Copyright (C) 2023 Thomas Basler and others
#
import os
import subprocess
import re

Import("env")

def getPatchPath(env):
    patchList = []
    for patch in env.GetProjectOption('custom_patches').split(","):
        patchList.append(os.path.join(env["PROJECT_DIR"], "patches", patch))
    return patchList

def is_tool(name):
    """Check whether `name` is on PATH and marked as executable."""

    # from whichcraft import which
    from shutil import which

    return which(name) is not None

def replaceInFile(in_file, out_file, text, subs, flags=0):
    """Function for replacing content for the given file."""

    if os.path.exists(in_file):
        #read the file contents
        with open(in_file, "r", encoding="utf-8") as infile:
            file_contents = infile.read()

        # do replacement
        text_pattern = re.compile(re.escape(text), flags)
        file_contents = text_pattern.sub(subs, file_contents)

        # write the result
        with open(out_file, "w", encoding="utf-8") as outfile:
            outfile.write(file_contents)

def main():
    if (env.GetProjectOption('custom_patches', '') == ''):
        print('No custom_patches specified')
        return

    if (not is_tool('git')):
        print('Git not found. Will not apply custom patches!')
        return

    directories = getPatchPath(env)
    for directory in directories:
        if (not os.path.isdir(directory)):
            print('Patch directory not found: ' + directory)
            return

        for file in os.listdir(directory):
            if (not file.endswith('.patch')):
                continue

            fullPath = os.path.join(directory, file)
            preparePath = fullPath + '.prepare'
            replaceInFile(fullPath, preparePath, '$$$env$$$', env['PIOENV'])
            print('Working on patch: ' + fullPath + '... ', end='')

            # Check if patch was already applied
            process = subprocess.run(['git', 'apply', '--reverse', '--check', preparePath], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
            if (process.returncode == 0):
                print('already applied')
                os.remove(preparePath)
                continue

            # Apply patch
            process = subprocess.run(['git', 'apply', preparePath])
            if (process.returncode == 0):
                print('applied')
            else:
                print('failed')

            os.remove(preparePath)


main()