import logging
import os
from pathlib import Path
import shutil
import re
import sys

sys.path.append(os.path.dirname(__file__))

from common import exec_checked, exec_get_output, prompt, escape_filename, get_root, replace_in_file, run_script

_invalid_file_char_regex = re.compile(r'[^a-zA-Z0-9_]')
_variable_regex = re.compile(r'@([A-Z_]+)@')
_logger = logging.getLogger(__name__)
_root : Path

def verify_tools() -> None:
    _logger.debug('Verifying all required tools are available...')
    success = True
    if shutil.which('git') is None:
        _logger.error('git not found in PATH')
        success = False
    if shutil.which('scons') is None:
        _logger.error('SCons not found in PATH')
        success = False
    if not success:
        raise RuntimeError('one or more required tools could not be found')

def download_spp() -> None:
    _logger.debug('Checking if Scons++ is checked out...')
    output = exec_get_output(['git', 'submodule', 'status', 'external/scons-plus-plus'])
    if output[0] in ('+', ' '):
        return
    assert output[0] == '-'
    _logger.info('SCons++ not checkout out yet, doing it now.')
    exec_checked(['git', 'submodule', 'init'])
    exec_checked(['git', 'submodule', 'update', 'external/scons-plus-plus'])

def update_spp() -> None:
    _logger.debug('Updating SCons++ submodule...')
    os.chdir(_root / 'external/scons-plus-plus')
    try:
        exec_checked(['git', 'fetch', 'origin', 'master'])
        exec_checked(['git', 'checkout', 'master'])
        output = exec_get_output(['git', 'status', '--porcelain'])
        if output.strip() == '':
            return
    finally:
        os.chdir(_root)
    _logger.info('Changes in SCons++ detected, creating commit.')
    exec_checked(['git', 'commit', '-m', 'Updated Scons++', 'external/scons-plus-plus'])

def verify_unchanged() -> None:
    output = exec_get_output(['git', 'status', '--porcelain'])
    if output != '':
        raise RuntimeError('There are uncommitted changes. Commit, stash or revert them before running this script.')

def setup_project() -> None:
    project_name = ''
    while project_name == '':
        print('Please enter a name for your project.')
        project_name = prompt().strip()
    module_name = project_name
    print(f'Please enter a name for the first module. Leave empty to use the project name ("{module_name}").')
    new_name = prompt().strip()
    if new_name != '':
        module_name = new_name
    
    module_folder_name = escape_filename(project_name.lower())
    print(f'Please enter a folder name for the first module. Leave empty for "{module_folder_name}". Anything but [A-Za-z0-9_] will be replaced with underscores.')
    new_name = prompt().strip()
    if new_name != '':
        module_folder_name = escape_filename(new_name) # just enforce nice names

    module_exe_name = escape_filename(module_name.lower())
    print(f'Please enter a file name for the module executable. Leave empty for "{module_exe_name}". Omit the file suffix. Anything but [A-Za-z0-9_] will be replaced with underscores.')
    new_name = prompt().strip()
    if new_name != '':
        module_exe_name = escape_filename(new_name)

    
    replace_in_file(_root / 'SConstruct', PROJECT_NAME=project_name, MODULE_FOLDER_NAME=module_folder_name)
    replace_in_file(_root / 'private/spp_template/SModule', MODULE_NAME=module_name, EXE_NAME=module_exe_name)
    
    template_folder = _root / 'private/spp_template'
    module_folder = _root / 'private' / module_folder_name
    _logger.debug(f'Moving {template_folder} to {module_folder}.')
    shutil.move(template_folder, module_folder)

    _logger.info('Creating a git commit for the setup.')
    exec_checked(['git', 'add', '.'])
    exec_checked(['git', 'commit', '-m', 'Project setup'])

def setup_git_remote() -> None:
    current_url = exec_get_output(['git', 'remote', 'get-url', 'origin'])
    if 'spp_template' not in current_url:
        _logger.debug('Remote already set up.')
        return

    remote_url = ''
    while remote_url == '':
        print('Please enter a new URL for your git remote.')
        remote_url = prompt().strip()
    exec_checked(['git', 'remote', 'set-url', 'origin', remote_url])
    

def script_main():
    global _root
    _root = get_root()
    verify_tools()
    download_spp()
    update_spp()
    verify_unchanged()
    setup_project()
    setup_git_remote()

if __name__ == '__main__':
    run_script(script_main)