from os.path import (join, dirname, isdir, normpath, splitext, basename)
from os import listdir, walk, sep
import sh
import shlex
import glob
import importlib
import os
import shutil

from pythonforandroid.logger import (warning, shprint, info, logger,
                                     debug)
from pythonforandroid.util import (current_directory, ensure_dir,
                                   temp_directory)
from pythonforandroid.recipe import Recipe


def copy_files(src_root, dest_root, override=True):
    for root, dirnames, filenames in walk(src_root):
        for filename in filenames:
            subdir = normpath(root.replace(src_root, ""))
            if subdir.startswith(sep):  # ensure it is relative
                subdir = subdir[1:]
            dest_dir = join(dest_root, subdir)
            if not os.path.exists(dest_dir):
                os.makedirs(dest_dir)
            src_file = join(root, filename)
            dest_file = join(dest_dir, filename)
            if os.path.isfile(src_file):
                if override and os.path.exists(dest_file):
                    os.unlink(dest_file)
                if not os.path.exists(dest_file):
                    shutil.copy(src_file, dest_file)
            else:
                os.makedirs(dest_file)


class Bootstrap(object):
    '''An Android project template, containing recipe stuff for
    compilation and templated fields for APK info.
    '''
    name = ''
    jni_subdir = '/jni'
    ctx = None

    bootstrap_dir = None

    build_dir = None
    dist_dir = None
    dist_name = None
    distribution = None

    # All bootstraps should include Python in some way:
    recipe_depends = [
        ("python2", "python2legacy", "python3", "python3crystax"),
        'android',
    ]

    can_be_chosen_automatically = True
    '''Determines whether the bootstrap can be chosen as one that
    satisfies user requirements. If False, it will not be returned
    from Bootstrap.get_bootstrap_from_recipes.
    '''

    # Other things a Bootstrap might need to track (maybe separately):
    # ndk_main.c
    # whitelist.txt
    # blacklist.txt

    @property
    def dist_dir(self):
        '''The dist dir at which to place the finished distribution.'''
        if self.distribution is None:
            warning('Tried to access {}.dist_dir, but {}.distribution '
                    'is None'.format(self, self))
            exit(1)
        return self.distribution.dist_dir

    @property
    def jni_dir(self):
        return self.name + self.jni_subdir

    def check_recipe_choices(self):
        '''Checks what recipes are being built to see which of the alternative
        and optional dependencies are being used,
        and returns a list of these.'''
        recipes = []
        built_recipes = self.ctx.recipe_build_order
        for recipe in self.recipe_depends:
            if isinstance(recipe, (tuple, list)):
                for alternative in recipe:
                    if alternative in built_recipes:
                        recipes.append(alternative)
                        break
        return sorted(recipes)

    def get_build_dir_name(self):
        choices = self.check_recipe_choices()
        dir_name = '-'.join([self.name] + choices)
        return dir_name

    def get_build_dir(self):
        return join(self.ctx.build_dir, 'bootstrap_builds', self.get_build_dir_name())

    def get_dist_dir(self, name):
        return join(self.ctx.dist_dir, name)

    def get_common_dir(self):
        return os.path.abspath(join(self.bootstrap_dir, "..", 'common'))

    @property
    def name(self):
        modname = self.__class__.__module__
        return modname.split(".", 2)[-1]

    def prepare_build_dir(self):
        '''Ensure that a build dir exists for the recipe. This same single
        dir will be used for building all different archs.'''
        self.build_dir = self.get_build_dir()
        self.common_dir = self.get_common_dir()
        copy_files(join(self.bootstrap_dir, 'build'), self.build_dir)
        copy_files(join(self.common_dir, 'build'), self.build_dir,
                   override=False)
        if self.ctx.symlink_java_src:
            info('Symlinking java src instead of copying')
            shprint(sh.rm, '-r', join(self.build_dir, 'src'))
            shprint(sh.mkdir, join(self.build_dir, 'src'))
            for dirn in listdir(join(self.bootstrap_dir, 'build', 'src')):
                shprint(sh.ln, '-s', join(self.bootstrap_dir, 'build', 'src', dirn),
                        join(self.build_dir, 'src'))
        with current_directory(self.build_dir):
            with open('project.properties', 'w') as fileh:
                fileh.write('target=android-{}'.format(self.ctx.android_api))

    def prepare_dist_dir(self, name):
        ensure_dir(self.dist_dir)

    def run_distribute(self):
        self.distribution.save_info(self.dist_dir)

    @classmethod
    def list_bootstraps(cls):
        '''Find all the available bootstraps and return them.'''
        forbidden_dirs = ('__pycache__', 'common')
        bootstraps_dir = join(dirname(__file__), 'bootstraps')
        for name in listdir(bootstraps_dir):
            if name in forbidden_dirs:
                continue
            filen = join(bootstraps_dir, name)
            if isdir(filen):
                yield name

    @classmethod
    def get_bootstrap_from_recipes(cls, recipes, ctx):
        '''Returns a bootstrap whose recipe requirements do not conflict with
        the given recipes.'''
        info('Trying to find a bootstrap that matches the given recipes.')
        bootstraps = [cls.get_bootstrap(name, ctx)
                      for name in cls.list_bootstraps()]
        acceptable_bootstraps = []
        for bs in bootstraps:
            if not bs.can_be_chosen_automatically:
                continue
            possible_dependency_lists = expand_dependencies(bs.recipe_depends)
            for possible_dependencies in possible_dependency_lists:
                ok = True
                for recipe in possible_dependencies:
                    recipe = Recipe.get_recipe(recipe, ctx)
                    if any([conflict in recipes for conflict in recipe.conflicts]):
                        ok = False
                        break
                for recipe in recipes:
                    try:
                        recipe = Recipe.get_recipe(recipe, ctx)
                    except ValueError:
                        conflicts = []
                    else:
                        conflicts = recipe.conflicts
                    if any([conflict in possible_dependencies
                            for conflict in conflicts]):
                        ok = False
                        break
                if ok and bs not in acceptable_bootstraps:
                    acceptable_bootstraps.append(bs)
        info('Found {} acceptable bootstraps: {}'.format(
            len(acceptable_bootstraps),
            [bs.name for bs in acceptable_bootstraps]))
        if acceptable_bootstraps:
            info('Using the first of these: {}'
                 .format(acceptable_bootstraps[0].name))
            return acceptable_bootstraps[0]
        return None

    @classmethod
    def get_bootstrap(cls, name, ctx):
        '''Returns an instance of a bootstrap with the given name.

        This is the only way you should access a bootstrap class, as
        it sets the bootstrap directory correctly.
        '''
        if name is None:
            return None
        if not hasattr(cls, 'bootstraps'):
            cls.bootstraps = {}
        if name in cls.bootstraps:
            return cls.bootstraps[name]
        mod = importlib.import_module('pythonforandroid.bootstraps.{}'
                                      .format(name))
        if len(logger.handlers) > 1:
            logger.removeHandler(logger.handlers[1])
        bootstrap = mod.bootstrap
        bootstrap.bootstrap_dir = join(ctx.root_dir, 'bootstraps', name)
        bootstrap.ctx = ctx
        return bootstrap

    def distribute_libs(self, arch, src_dirs, wildcard='*', dest_dir="libs"):
        '''Copy existing arch libs from build dirs to current dist dir.'''
        info('Copying libs')
        tgt_dir = join(dest_dir, arch.arch)
        ensure_dir(tgt_dir)
        for src_dir in src_dirs:
            for lib in glob.glob(join(src_dir, wildcard)):
                shprint(sh.cp, '-a', lib, tgt_dir)

    def distribute_javaclasses(self, javaclass_dir, dest_dir="src"):
        '''Copy existing javaclasses from build dir to current dist dir.'''
        info('Copying java files')
        ensure_dir(dest_dir)
        for filename in glob.glob(javaclass_dir):
            shprint(sh.cp, '-a', filename, dest_dir)

    def distribute_aars(self, arch):
        '''Process existing .aar bundles and copy to current dist dir.'''
        info('Unpacking aars')
        for aar in glob.glob(join(self.ctx.aars_dir, '*.aar')):
            self._unpack_aar(aar, arch)

    def _unpack_aar(self, aar, arch):
        '''Unpack content of .aar bundle and copy to current dist dir.'''
        with temp_directory() as temp_dir:
            name = splitext(basename(aar))[0]
            jar_name = name + '.jar'
            info("unpack {} aar".format(name))
            debug("  from {}".format(aar))
            debug("  to {}".format(temp_dir))
            shprint(sh.unzip, '-o', aar, '-d', temp_dir)

            jar_src = join(temp_dir, 'classes.jar')
            jar_tgt = join('libs', jar_name)
            debug("copy {} jar".format(name))
            debug("  from {}".format(jar_src))
            debug("  to {}".format(jar_tgt))
            ensure_dir('libs')
            shprint(sh.cp, '-a', jar_src, jar_tgt)

            so_src_dir = join(temp_dir, 'jni', arch.arch)
            so_tgt_dir = join('libs', arch.arch)
            debug("copy {} .so".format(name))
            debug("  from {}".format(so_src_dir))
            debug("  to {}".format(so_tgt_dir))
            ensure_dir(so_tgt_dir)
            so_files = glob.glob(join(so_src_dir, '*.so'))
            for f in so_files:
                shprint(sh.cp, '-a', f, so_tgt_dir)

    def strip_libraries(self, arch):
        info('Stripping libraries')
        if self.ctx.python_recipe.from_crystax:
            info('Python was loaded from CrystaX, skipping strip')
            return
        env = arch.get_env()
        tokens = shlex.split(env['STRIP'])
        strip = sh.Command(tokens[0])
        if len(tokens) > 1:
            strip = strip.bake(tokens[1:])

        libs_dir = join(self.dist_dir, '_python_bundle',
                        '_python_bundle', 'modules')
        if self.ctx.python_recipe.name == 'python2legacy':
            libs_dir = join(self.dist_dir, 'private')
        filens = shprint(sh.find, libs_dir, join(self.dist_dir, 'libs'),
                         '-iname', '*.so', _env=env).stdout.decode('utf-8')

        logger.info('Stripping libraries in private dir')
        for filen in filens.split('\n'):
            if not filen:
                continue  # skip the last ''
            try:
                strip(filen, _env=env)
            except sh.ErrorReturnCode_1:
                logger.debug('Failed to strip ' + filen)

    def fry_eggs(self, sitepackages):
        info('Frying eggs in {}'.format(sitepackages))
        for d in listdir(sitepackages):
            rd = join(sitepackages, d)
            if isdir(rd) and d.endswith('.egg'):
                info('  ' + d)
                files = [join(rd, f) for f in listdir(rd) if f != 'EGG-INFO']
                if files:
                    shprint(sh.mv, '-t', sitepackages, *files)
                shprint(sh.rm, '-rf', d)


def expand_dependencies(recipes):
    recipe_lists = [[]]
    for recipe in recipes:
        if isinstance(recipe, (tuple, list)):
            new_recipe_lists = []
            for alternative in recipe:
                for old_list in recipe_lists:
                    new_list = [i for i in old_list]
                    new_list.append(alternative)
                    new_recipe_lists.append(new_list)
            recipe_lists = new_recipe_lists
        else:
            for old_list in recipe_lists:
                old_list.append(recipe)
    return recipe_lists
