#!/usr/bin/env python
from __future__ import print_function

import os
import re
import sys
import glob
from fnmatch import fnmatch
from os.path import join as pathjoin, relpath, dirname, \
                    abspath, basename, splitext


HERE = dirname(abspath(__file__))
AUTOGEN_WARNING = ('# ******** AUTOGENERATED by {0} ' +
                   ('*' * 20)).format(basename(sys.argv[0]))
PATTERN_RULE_MXMLC = \
    '$(MXMLC) {primary_dep} -warnings -l+={parent_dir} -output {target}'


def main(sysargs=sys.argv[:]):
    targets_mk = pathjoin(HERE, 'targets.mk')
    os.chmod(targets_mk, 0600)
    targetmaker = TargetMaker(outstream=open(targets_mk, 'wb'))
    targetmaker.make()
    os.chmod(targets_mk, 0444)
    return 0


class TargetMaker(object):
    _to_glob = (
        pathjoin(HERE, '[0-9]*-*', '*.mxml'),
        pathjoin(HERE, 'custom-*', '*.mxml'),
    )
    _source_fileexts = ('.mxml', '.as', '.css')

    def __init__(self, outstream=sys.stdout):
        self.outstream = outstream
        self.targets = {}

    def make(self):
        for pattern in self._to_glob:
            for mxml in glob.glob(pattern):
                self._add_target_from_mxml(mxml)
        self._write_out_targets()

    def _add_target_from_mxml(self, mxml):
        rel_mxml = relpath(mxml, HERE)
        as_swf = re.sub('(.*)\.mxml$', '\\1.swf', rel_mxml)
        self.targets[as_swf] = set([rel_mxml])

        self._add_deps_from_alt_source_file_extensions(as_swf, rel_mxml)

    def _add_deps_from_alt_source_file_extensions(self, as_swf, rel_mxml):
        basedir = dirname(rel_mxml)
        for dirpath, dirnames, filenames in os.walk(basedir):
            for filename in filenames:
                if ext(filename) in self._source_fileexts:
                    rel_source = relpath(pathjoin(dirpath, filename), HERE)
                    self.targets[as_swf].add(rel_source)

    def _write_out_targets(self):
        print(AUTOGEN_WARNING, file=self.outstream)
        for target in sorted(self.targets.iterkeys()):
            deps = self._get_deps_for_target(target)
            primary_dep = self._get_primary_dep(target, deps)
            pattern_rule_kwargs = \
                self._get_pattern_rule_kwargs(primary_dep, target)

            print('{target}: {deps}'.format(target=target,
                    deps=' '.join(deps)), file=self.outstream)
            print('\t' + PATTERN_RULE_MXMLC.format(**pattern_rule_kwargs) +
                  '\n\n', file=self.outstream)

    def _get_deps_for_target(self, target):
        deps = []
        for dep in reversed(sorted(list(self.targets[target]), key=ext)):
            deps.append(dep)
        return deps

    def _get_primary_dep(self, target, deps):
        primary_dep = deps[0]

        for dependency in deps:
            if fnmatch(target, namebase(dependency) + '.*'):
                primary_dep = dependency

        return primary_dep

    def _get_pattern_rule_kwargs(self, primary_dep, target):
        ret = dict(
            primary_dep=primary_dep,
            parent_dir=dirname(primary_dep),
            target=target
        )
        return ret

def ext(filename):
    return splitext(filename)[-1]


def namebase(filename):
    return splitext(filename)[0]


if __name__ == '__main__':
    sys.exit(main())

# vim:filetype=python