unmergeconfig

#! /usr/bin/env python
'''\
Create top level variables based on a higher level config

$Id$
'''
from __future__ import print_function

import sys
import io
import argparse
import package_info
import re
from feedback import die, warn

from configobj import Section
from expconfig import ConfigObj


#
# Helper routines
#

# Get base config keys that contain globals

global_matcher = re.compile(r'\$(\w+)')

def get_globals(config, result):
    for key in config.sections:
        get_globals_section(config[key], key,
            {s: '' for s in config.scalars}, result)

def get_globals_section(section, path, global_keys, result):
    all_keys = global_keys.copy()
    all_keys.update({s: path for s in section.scalars})
    for key in section.scalars:
        value = section[key]
        if not isinstance(value, (list, tuple)):
            match = global_matcher.match(value)
            if match:
                global_key = match.group(1)
                if True: ### global_key in global_keys:
                    result[path+'/'+key] = (global_key,
                        all_keys.get(global_key, ''))
    for key in section.sections:
        get_globals_section(section[key], path+'/'+key, all_keys, result)

def eval_globals(config, global_dict):
    for key in config.sections:
        eval_globals_section(config[key], key, global_dict)

def eval_globals_section(section, path, global_dict):
    for key in section.scalars:
        value = section[key]
        if not isinstance(value, (list, tuple)):
            global_key = path+'/'+key
            if global_key in global_dict:
                global_var, global_path = global_dict[global_key]
                global_section = section.main
                if global_path:
                    for name in global_path.split('/'):
                        global_section = global_section[name]
                if global_var in global_section:
                    if global_section[global_var] != value:
                        warn("global '%s' at '%s' already set to '%s', "
                            "keeping '%s' at '%s'", global_var, global_path,
                            global_section[global_var], global_key, value)
                    else:
                        section[key] = '$' + global_var
                else:
                    global_section[global_var] = value
                    section[key] = '$' + global_var
    for key in section.sections:
        eval_globals_section(section[key], path+'/'+key, global_dict)

#
# Main routine
#

# Check command line

command_line = argparse.ArgumentParser(description=__doc__.split('\n', 1)[0])
# TODO: print differences option,  ...
command_line.add_argument('--indent-string', default='  ', help='set indent string [%(default)s]')
command_line.add_argument('--inline-comments' , '-c', action='store_true',
                          help='compact white space before inline comments'
                               ' (BETA)')
command_line.add_argument('--trailing-space' , '-t', action='store_true',
                          help='remove white space at end of lines')
command_line.add_argument('base_config', help='name of high level config')
command_line.add_argument('config', help='name of low level/expanded config')
command_line.add_argument('-V', '--version', action='version',
                          version=package_info.version)
args = command_line.parse_args()


# File handling

try:
    base_config = ConfigObj(args.base_config, interpolation=False,
        file_error=True)
    config = ConfigObj(args.config, interpolation=False, file_error=True)
except IOError as error:
    die(error.args[0])

global_dict = {}
get_globals(base_config, global_dict)

### for k, v in global_dict.items():
###     print(k+':', v)

### exit()

eval_globals(config, global_dict)

### exit()

# Ready to roll out

lines = io.BytesIO()
config.write(lines)

lines.seek(0)
for line in io.TextIOWrapper(lines):
    if args.inline_comments: line = re.sub(r' = (.*?)  #', r' = \1 #', line)
    if args.trailing_space:
        print(line.rstrip())
    else:
        print(line, end='')