#!/usr/bin/env python2
"""
Tool for compiling iOS toolchain
================================

This tool intend to replace all the previous tools/ in shell script.
"""

import sys
from sys import stdout
from os.path import join, dirname, realpath, exists, isdir, basename
from os import listdir, unlink, makedirs, environ, chdir, getcwd, walk, remove
import zipfile
import tarfile
import importlib
import io
import json
import shutil
import fnmatch
from datetime import datetime
try:
    from urllib.request import FancyURLopener, urlcleanup
except ImportError:
    from urllib import FancyURLopener, urlcleanup

curdir = dirname(__file__)
sys.path.insert(0, join(curdir, "tools", "external"))

import sh


IS_PY3 = sys.version_info[0] >= 3


def shprint(command, *args, **kwargs):
    kwargs["_iter"] = True
    kwargs["_out_bufsize"] = 1
    kwargs["_err_to_out"] = True
    for line in command(*args, **kwargs):
        stdout.write(line)


def cache_execution(f):
    def _cache_execution(self, *args, **kwargs):
        state = self.ctx.state
        key = "{}.{}".format(self.name, f.__name__)
        force = kwargs.pop("force", False)
        if args:
            for arg in args:
                key += ".{}".format(arg)
        key_time = "{}.at".format(key)
        if key in state and not force:
            print("# (ignored) {} {}".format(f.__name__.capitalize(), self.name))
            return
        print("{} {}".format(f.__name__.capitalize(), self.name))
        f(self, *args, **kwargs)
        state[key] = True
        state[key_time] = str(datetime.utcnow())
    return _cache_execution


class ChromeDownloader(FancyURLopener):
    version = (
        'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 '
        '(KHTML, like Gecko) Chrome/28.0.1500.71 Safari/537.36')

urlretrieve = ChromeDownloader().retrieve


class JsonStore(object):
    """Replacement of shelve using json, needed for support python 2 and 3.
    """

    def __init__(self, filename):
        super(JsonStore, self).__init__()
        self.filename = filename
        self.data = {}
        if exists(filename):
            try:
                with io.open(filename, encoding='utf-8') as fd:
                    self.data = json.load(fd)
            except ValueError:
                print("Unable to read the state.db, content will be replaced.")

    def __getitem__(self, key):
        return self.data[key]

    def __setitem__(self, key, value):
        self.data[key] = value
        self.sync()

    def __delitem__(self, key):
        del self.data[key]
        self.sync()

    def __contains__(self, item):
        return item in self.data

    def get(self, item, default=None):
        return self.data.get(item, default)

    def keys(self):
        return self.data.keys()

    def remove_all(self, prefix):
        for key in self.data.keys()[:]:
            if not key.startswith(prefix):
                continue
            del self.data[key]
        self.sync()

    def sync(self):
        # http://stackoverflow.com/questions/12309269/write-json-data-to-file-in-python/14870531#14870531
        if IS_PY3:
            with open(self.filename, 'w') as fd:
                json.dump(self.data, fd, ensure_ascii=False)
        else:
            with io.open(self.filename, 'w', encoding='utf-8') as fd:
                fd.write(unicode(json.dumps(self.data, ensure_ascii=False)))

class Arch(object):
    def __init__(self, ctx):
        super(Arch, self).__init__()
        self.ctx = ctx
        self._ccsh = None

    def __str__(self):
        return self.arch

    @property
    def include_dirs(self):
        return [
            "{}/{}".format(
                self.ctx.include_dir,
                d.format(arch=self))
            for d in self.ctx.include_dirs]


    def get_env(self):
        include_dirs = [
            "-I{}/{}".format(
                self.ctx.include_dir,
                d.format(arch=self))
            for d in self.ctx.include_dirs]

        env = {}
        ccache = sh.which('ccache')
        cc = sh.xcrun("-find", "-sdk", self.sdk, "clang").strip()
        if ccache:
            ccache = ccache.strip()
            use_ccache = environ.get("USE_CCACHE", "1")
            if use_ccache != '1':
                env["CC"] = cc
            else:
                if not self._ccsh:
                    self._ccsh = ccsh = sh.mktemp().strip()
                    with open(ccsh, 'w') as f:
                        f.write('#!/bin/sh\n')
                        f.write(ccache + ' ' + cc + ' "$@"\n')
                    sh.chmod('+x', ccsh)
                else:
                    ccsh = self._ccsh
                env["USE_CCACHE"] = '1'
                env["CCACHE"] = ccache
                env["CC"] = ccsh

                env.update({k: v for k, v in environ.items() if k.startswith('CCACHE_')})
                env.setdefault('CCACHE_MAXSIZE', '10G')
                env.setdefault('CCACHE_HARDLINK', 'true')
                env.setdefault('CCACHE_SLOPPINESS', ('file_macro,time_macros,'
                    'include_file_mtime,include_file_ctime,file_stat_matches'))
        else:
            env["CC"] = cc
        env["AR"] = sh.xcrun("-find", "-sdk", self.sdk, "ar").strip()
        env["LD"] = sh.xcrun("-find", "-sdk", self.sdk, "ld").strip()
        env["OTHER_CFLAGS"] = " ".join(include_dirs)
        env["OTHER_LDFLAGS"] = " ".join([
            "-L{}/{}".format(self.ctx.dist_dir, "lib"),
        ])
        env["CFLAGS"] = " ".join([
            "-arch", self.arch,
            "-pipe", "-no-cpp-precomp",
            "--sysroot", self.sysroot,
            #"-I{}/common".format(self.ctx.include_dir),
            #"-I{}/{}".format(self.ctx.include_dir, self.arch),
            "-O3",
            self.version_min
        ] + include_dirs)
        env["LDFLAGS"] = " ".join([
            "-arch", self.arch,
            "--sysroot", self.sysroot,
            "-L{}/{}".format(self.ctx.dist_dir, "lib"),
            "-lsqlite3",
            self.version_min
        ])
        return env



class ArchSimulator(Arch):
    sdk = "iphonesimulator"
    arch = "i386"
    triple = "i386-apple-darwin11"
    version_min = "-miphoneos-version-min=6.0.0"
    sysroot = sh.xcrun("--sdk", "iphonesimulator", "--show-sdk-path").strip()


class Arch64Simulator(Arch):
    sdk = "iphonesimulator"
    arch = "x86_64"
    triple = "x86_64-apple-darwin13"
    version_min = "-miphoneos-version-min=7.0"
    sysroot = sh.xcrun("--sdk", "iphonesimulator", "--show-sdk-path").strip()


class ArchIOS(Arch):
    sdk = "iphoneos"
    arch = "armv7"
    triple = "arm-apple-darwin11"
    version_min = "-miphoneos-version-min=6.0.0"
    sysroot = sh.xcrun("--sdk", "iphoneos", "--show-sdk-path").strip()


class Arch64IOS(Arch):
    sdk = "iphoneos"
    arch = "arm64"
    triple = "aarch64-apple-darwin13"
    version_min = "-miphoneos-version-min=7.0"
    sysroot = sh.xcrun("--sdk", "iphoneos", "--show-sdk-path").strip()


class Graph(object):
    # Taken from python-for-android/depsort
    def __init__(self):
        # `graph`: dict that maps each package to a set of its dependencies.
        self.graph = {}

    def add(self, dependent, dependency):
        """Add a dependency relationship to the graph"""
        self.graph.setdefault(dependent, set())
        self.graph.setdefault(dependency, set())
        if dependent != dependency:
            self.graph[dependent].add(dependency)

    def add_optional(self, dependent, dependency):
        """Add an optional (ordering only) dependency relationship to the graph

        Only call this after all mandatory requirements are added
        """
        if dependent in self.graph and dependency in self.graph:
            self.add(dependent, dependency)

    def find_order(self):
        """Do a topological sort on a dependency graph

        :Parameters:
            :Returns:
                iterator, sorted items form first to last
        """
        graph = dict((k, set(v)) for k, v in self.graph.items())
        while graph:
            # Find all items without a parent
            leftmost = [l for l, s in graph.items() if not s]
            if not leftmost:
                raise ValueError('Dependency cycle detected! %s' % graph)
            # If there is more than one, sort them for predictable order
            leftmost.sort()
            for result in leftmost:
                # Yield and remove them from the graph
                yield result
                graph.pop(result)
                for bset in graph.values():
                    bset.discard(result)


class Context(object):
    env = environ.copy()
    root_dir = None
    cache_dir = None
    build_dir = None
    dist_dir = None
    install_dir = None
    ccache = None
    cython = None
    sdkver = None
    sdksimver = None

    def __init__(self):
        super(Context, self).__init__()
        self.include_dirs = []

        ok = True

        sdks = sh.xcodebuild("-showsdks").splitlines()

        # get the latest iphoneos
        iphoneos = [x for x in sdks if "iphoneos" in x]
        if not iphoneos:
            print("No iphone SDK installed")
            ok = False
        else:
            iphoneos = iphoneos[0].split()[-1].replace("iphoneos", "")
            self.sdkver = iphoneos

        # get the latest iphonesimulator version
        iphonesim = [x for x in sdks if "iphonesimulator" in x]
        if not iphonesim:
            ok = False
            print("Error: No iphonesimulator SDK installed")
        else:
            iphonesim = iphonesim[0].split()[-1].replace("iphonesimulator", "")
            self.sdksimver = iphonesim

        # get the path for Developer
        self.devroot = "{}/Platforms/iPhoneOS.platform/Developer".format(
            sh.xcode_select("-print-path").strip())

        # path to the iOS SDK
        self.iossdkroot = "{}/SDKs/iPhoneOS{}.sdk".format(
            self.devroot, self.sdkver)

        # root of the toolchain
        self.root_dir = realpath(dirname(__file__))
        self.build_dir = "{}/build".format(self.root_dir)
        self.cache_dir = "{}/.cache".format(self.root_dir)
        self.dist_dir = "{}/dist".format(self.root_dir)
        self.install_dir = "{}/dist/root".format(self.root_dir)
        self.include_dir = "{}/dist/include".format(self.root_dir)
        self.archs = (
            ArchSimulator(self),
            Arch64Simulator(self),
            ArchIOS(self),
            Arch64IOS(self))

        # path to some tools
        self.ccache = sh.which("ccache")
        if not self.ccache:
            #print("ccache is missing, the build will not be optimized in the future.")
            pass
        for cython_fn in ("cython-2.7", "cython"):
            cython = sh.which(cython_fn)
            if cython:
                self.cython = cython
                break
        if not self.cython:
            ok = False
            print("Missing requirement: cython is not installed")

        # check the basic tools
        for tool in ("pkg-config", "autoconf", "automake", "libtool"):
            if not sh.which(tool):
                print("Missing requirement: {} is not installed".format(
                    tool))

        if not ok:
            sys.exit(1)

        self.use_pigz = sh.which('pigz')
        self.use_pbzip2 = sh.which('pbzip2')

        try:
            num_cores = int(sh.sysctl('-n', 'hw.ncpu'))
        except Exception:
            num_cores = None
        self.num_cores = num_cores if num_cores else 4  # default to 4 if we can't detect

        ensure_dir(self.root_dir)
        ensure_dir(self.build_dir)
        ensure_dir(self.cache_dir)
        ensure_dir(self.dist_dir)
        ensure_dir(self.install_dir)
        ensure_dir(self.include_dir)
        ensure_dir(join(self.include_dir, "common"))

        # remove the most obvious flags that can break the compilation
        self.env.pop("MACOSX_DEPLOYMENT_TARGET", None)
        self.env.pop("PYTHONDONTWRITEBYTECODE", None)
        self.env.pop("ARCHFLAGS", None)
        self.env.pop("CFLAGS", None)
        self.env.pop("LDFLAGS", None)

        # set the state
        self.state = JsonStore(join(self.dist_dir, "state.db"))

    @property
    def concurrent_make(self):
        return "-j{}".format(self.num_cores)

    @property
    def concurrent_xcodebuild(self):
        return "IDEBuildOperationMaxNumberOfConcurrentCompileTasks={}".format(self.num_cores)


class Recipe(object):
    version = None
    url = None
    archs = []
    depends = []
    optional_depends = []
    library = None
    libraries = []
    include_dir = None
    include_per_arch = False
    frameworks = []
    sources = []
    pbx_frameworks = []
    pbx_libraries = []

    # API available for recipes
    def download_file(self, url, filename, cwd=None):
        """
        Download an `url` to `outfn`
        """
        if not url:
            return
        def report_hook(index, blksize, size):
            if size <= 0:
                progression = '{0} bytes'.format(index * blksize)
            else:
                progression = '{0:.2f}%'.format(
                        index * blksize * 100. / float(size))
            stdout.write('- Download {}\r'.format(progression))
            stdout.flush()

        if cwd:
            filename = join(cwd, filename)
        if exists(filename):
            unlink(filename)

        # Clean up temporary files just in case before downloading.
        urlcleanup()

        print('Downloading {0}'.format(url))
        urlretrieve(url, filename, report_hook)
        return filename

    def extract_file(self, filename, cwd):
        """
        Extract the `filename` into the directory `cwd`.
        """
        if not filename:
            return
        print("Extract {} into {}".format(filename, cwd))
        if filename.endswith(".tgz") or filename.endswith(".tar.gz"):
            if self.ctx.use_pigz:
                comp = '--use-compress-program={}'.format(self.ctx.use_pigz)
            else:
                comp = '-z'
            shprint(sh.tar, "-C", cwd, "-xv", comp, "-f", filename)

        elif filename.endswith(".tbz2") or filename.endswith(".tar.bz2"):
            if self.ctx.use_pbzip2:
                comp = '--use-compress-program={}'.format(self.ctx.use_pbzip2)
            else:
                comp = '-j'
            shprint(sh.tar, "-C", cwd, "-xv", comp, "-f", filename)

        elif filename.endswith(".zip"):
            shprint(sh.unzip, "-d", cwd, filename)

        else:
            print("Error: cannot extract, unrecognized extension for {}".format(
                filename))
            raise Exception()

    def get_archive_rootdir(self, filename):
        if filename.endswith(".tgz") or filename.endswith(".tar.gz") or \
                filename.endswith(".tbz2") or filename.endswith(".tar.bz2"):
            try:
                archive = tarfile.open(filename)
            except tarfile.ReadError:
                print('Error extracting the archive {0}'.format(filename))
                print('This is usually caused by a corrupt download. The file'
                      ' will be removed and re-downloaded on the next run.')
                remove(filename)
                return

            root = archive.next().path.split("/")
            return root[0]
        elif filename.endswith(".zip"):
            with zipfile.ZipFile(filename) as zf:
                return dirname(zf.namelist()[0])
        else:
            print("Error: cannot detect root directory")
            print("Unrecognized extension for {}".format(filename))
            raise Exception()

    def apply_patch(self, filename, target_dir=''):
        """
        Apply a patch from the current recipe directory into the current
        build directory.
        """
        target_dir = target_dir or self.build_dir
        print("Apply patch {}".format(filename))
        filename = join(self.recipe_dir, filename)
        sh.patch("-t", "-d", target_dir, "-p1", "-i", filename)

    def copy_file(self, filename, dest):
        print("Copy {} to {}".format(filename, dest))
        filename = join(self.recipe_dir, filename)
        dest = join(self.build_dir, dest)
        shutil.copy(filename, dest)

    def append_file(self, filename, dest):
        print("Append {} to {}".format(filename, dest))
        filename = join(self.recipe_dir, filename)
        dest = join(self.build_dir, dest)
        with open(filename, "rb") as fd:
            data = fd.read()
        with open(dest, "ab") as fd:
            fd.write(data)

    def has_marker(self, marker):
        """
        Return True if the current build directory has the marker set
        """
        return exists(join(self.build_dir, ".{}".format(marker)))

    def set_marker(self, marker):
        """
        Set a marker info the current build directory
        """
        with open(join(self.build_dir, ".{}".format(marker)), "w") as fd:
            fd.write("ok")

    def delete_marker(self, marker):
        """
        Delete a specific marker
        """
        try:
            unlink(join(self.build_dir, ".{}".format(marker)))
        except:
            pass

    def get_include_dir(self):
        """
        Return the common include dir for this recipe
        """
        return join(self.ctx.include_dir, "common", self.name)

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

    @property
    def archive_fn(self):
        bfn = basename(self.url.format(version=self.version))
        fn = "{}/{}-{}".format(
            self.ctx.cache_dir,
            self.name, bfn)
        return fn

    @property
    def filtered_archs(self):
        result = []
        for arch in self.ctx.archs:
            if not self.archs or (arch.arch in self.archs):
                result.append(arch)
        return result

    @property
    def dist_libraries(self):
        libraries = []
        name = self.name
        if not name.startswith("lib"):
            name = "lib{}".format(name)
        if self.library:
            static_fn = join(self.ctx.dist_dir, "lib", "{}.a".format(name))
            libraries.append(static_fn)
        for library in self.libraries:
            static_fn = join(self.ctx.dist_dir, "lib", basename(library))
            libraries.append(static_fn)
        return libraries

    def get_build_dir(self, arch):
        return join(self.ctx.build_dir, self.name, arch, self.archive_root)

    # Public Recipe API to be subclassed if needed

    def init_with_ctx(self, ctx):
        self.ctx = ctx
        include_dir = None
        if self.include_dir:
            if self.include_per_arch:
                include_dir = join("{arch.arch}", self.name)
            else:
                include_dir = join("common", self.name)
        if include_dir:
            print("Include dir added: {}".format(include_dir))
            self.ctx.include_dirs.append(include_dir)

    def get_recipe_env(self, arch=None):
        """Return the env specialized for the recipe
        """
        if arch is None:
            arch = self.filtered_archs[0]
        return arch.get_env()

    @property
    def archive_root(self):
        key = "{}.archive_root".format(self.name)
        value = self.ctx.state.get(key)
        if not value:
            value = self.get_archive_rootdir(self.archive_fn)
            if value is not None:
                self.ctx.state[key] = value
        return value

    def execute(self):
        if self.custom_dir:
            self.ctx.state.remove_all(self.name)
        self.download()
        self.extract()
        self.build_all()

    @property
    def custom_dir(self):
        """Check if there is a variable name to specify a custom version /
        directory to use instead of the current url.
        """
        envname = "{}_DIR".format(self.name.upper())
        d = environ.get(envname)
        if not d:
            return
        if not exists(d):
            raise ValueError("Invalid path passed into {}".format(envname))
        return d

    @cache_execution
    def download(self):
        key = "{}.archive_root".format(self.name)
        if self.custom_dir:
            self.ctx.state[key] = basename(self.custom_dir)
        else:
            src_dir = join(self.recipe_dir, self.url)
            if exists(src_dir):
                self.ctx.state[key] = basename(src_dir)
                return
            fn = self.archive_fn
            if not exists(fn):
                self.download_file(self.url.format(version=self.version), fn)
            status = self.get_archive_rootdir(self.archive_fn)
            if status is not None:
                self.ctx.state[key] = status

    @cache_execution
    def extract(self):
        # recipe tmp directory
        for arch in self.filtered_archs:
            print("Extract {} for {}".format(self.name, arch.arch))
            self.extract_arch(arch.arch)

    def extract_arch(self, arch):
        build_dir = join(self.ctx.build_dir, self.name, arch)
        dest_dir = join(build_dir, self.archive_root)
        if self.custom_dir:
            if exists(dest_dir):
                shutil.rmtree(dest_dir)
            shutil.copytree(self.custom_dir, dest_dir)
        else:
            if exists(dest_dir):
                return
            src_dir = join(self.recipe_dir, self.url)
            if exists(src_dir):
                shutil.copytree(src_dir, dest_dir)
                return
            ensure_dir(build_dir)
            self.extract_file(self.archive_fn, build_dir)

    @cache_execution
    def build(self, arch):
        self.build_dir = self.get_build_dir(arch.arch)
        if self.has_marker("building"):
            print("Warning: {} build for {} has been incomplete".format(
                self.name, arch.arch))
            print("Warning: deleting the build and restarting.")
            shutil.rmtree(self.build_dir)
            self.extract_arch(arch.arch)

        if self.has_marker("build_done"):
            print("Build python for {} already done.".format(arch.arch))
            return

        self.set_marker("building")

        chdir(self.build_dir)
        print("Prebuild {} for {}".format(self.name, arch.arch))
        self.prebuild_arch(arch)
        print("Build {} for {}".format(self.name, arch.arch))
        self.build_arch(arch)
        print("Postbuild {} for {}".format(self.name, arch.arch))
        self.postbuild_arch(arch)
        self.delete_marker("building")
        self.set_marker("build_done")

    @cache_execution
    def build_all(self):
        filtered_archs = self.filtered_archs
        print("Build {} for {} (filtered)".format(
            self.name,
            ", ".join([x.arch for x in filtered_archs])))
        for arch in self.filtered_archs:
            self.build(arch)

        name = self.name
        if self.library:
            print("Create lipo library for {}".format(name))
            if not name.startswith("lib"):
                name = "lib{}".format(name)
            static_fn = join(self.ctx.dist_dir, "lib", "{}.a".format(name))
            ensure_dir(dirname(static_fn))
            print("Lipo {} to {}".format(self.name, static_fn))
            self.make_lipo(static_fn)
        if self.libraries:
            print("Create multiple lipo for {}".format(name))
            for library in self.libraries:
                static_fn = join(self.ctx.dist_dir, "lib", basename(library))
                ensure_dir(dirname(static_fn))
                print("  - Lipo-ize {}".format(library))
                self.make_lipo(static_fn, library)
        print("Install include files for {}".format(self.name))
        self.install_include()
        print("Install frameworks for {}".format(self.name))
        self.install_frameworks()
        print("Install sources for {}".format(self.name))
        self.install_sources()
        print("Install {}".format(self.name))
        self.install()

    def prebuild_arch(self, arch):
        prebuild = "prebuild_{}".format(arch.arch)
        if hasattr(self, prebuild):
            getattr(self, prebuild)()

    def build_arch(self, arch):
        build = "build_{}".format(arch.arch)
        if hasattr(self, build):
            getattr(self, build)()

    def postbuild_arch(self, arch):
        postbuild = "postbuild_{}".format(arch.arch)
        if hasattr(self, postbuild):
            getattr(self, postbuild)()

    @cache_execution
    def make_lipo(self, filename, library=None):
        if library is None:
            library = self.library
        if not library:
            return
        args = []
        for arch in self.filtered_archs:
            library_fn = library.format(arch=arch)
            args += [
                "-arch", arch.arch,
                join(self.get_build_dir(arch.arch), library_fn)]
        shprint(sh.lipo, "-create", "-output", filename, *args)

    @cache_execution
    def install_frameworks(self):
        if not self.frameworks:
            return
        arch = self.filtered_archs[0]
        build_dir = self.get_build_dir(arch.arch)
        for framework in self.frameworks:
            print(" - Install {}".format(framework))
            src = join(build_dir, framework)
            dest = join(self.ctx.dist_dir, "frameworks", framework)
            ensure_dir(dirname(dest))
            if exists(dest):
                shutil.rmtree(dest)
            shutil.copytree(src, dest)

    @cache_execution
    def install_sources(self):
        if not self.sources:
            return
        arch = self.filtered_archs[0]
        build_dir = self.get_build_dir(arch.arch)
        for source in self.sources:
            print(" - Install {}".format(source))
            src = join(build_dir, source)
            dest = join(self.ctx.dist_dir, "sources", self.name)
            ensure_dir(dirname(dest))
            if exists(dest):
                shutil.rmtree(dest)
            shutil.copytree(src, dest)

    @cache_execution
    def install_include(self):
        if not self.include_dir:
            return
        if self.include_per_arch:
            archs = self.ctx.archs
        else:
            archs = self.filtered_archs[:1]

        include_dirs = self.include_dir
        if not isinstance(include_dirs, (list, tuple)):
            include_dirs = list([include_dirs])

        for arch in archs:
            arch_dir = "common"
            if self.include_per_arch:
                arch_dir = arch.arch
            dest_dir = join(self.ctx.include_dir, arch_dir, self.name)
            if exists(dest_dir):
                shutil.rmtree(dest_dir)
            build_dir = self.get_build_dir(arch.arch)

            for include_dir in include_dirs:
                dest_name = None
                if isinstance(include_dir, (list, tuple)):
                    include_dir, dest_name = include_dir
                include_dir = include_dir.format(arch=arch, ctx=self.ctx)
                src_dir = join(build_dir, include_dir)
                if dest_name is None:
                    dest_name = basename(src_dir)
                if isdir(src_dir):
                    shutil.copytree(src_dir, dest_dir)
                else:
                    dest = join(dest_dir, dest_name)
                    print("Copy {} to {}".format(src_dir, dest))
                    ensure_dir(dirname(dest))
                    shutil.copy(src_dir, dest)

    @cache_execution
    def install(self):
        pass

    @classmethod
    def list_recipes(cls):
        recipes_dir = join(dirname(__file__), "recipes")
        for name in listdir(recipes_dir):
            fn = join(recipes_dir, name)
            if isdir(fn):
                yield name

    @classmethod
    def get_recipe(cls, name, ctx):
        if not hasattr(cls, "recipes"):
           cls.recipes = {}

        if '==' in name:
            name, version = name.split('==')
        else:
            version = None

        if name in cls.recipes:
            recipe = cls.recipes[name]
        else:
            mod = importlib.import_module("recipes.{}".format(name))
            recipe = mod.recipe
            recipe.recipe_dir = join(ctx.root_dir, "recipes", name)

        if version:
            recipe.version = version

        return recipe


class PythonRecipe(Recipe):
    @cache_execution
    def install(self):
        self.install_python_package()
        self.reduce_python_package()

    @staticmethod
    def remove_junk(d):
        exts = [".pyc", ".py", ".so.lib", ".so.o", ".sh"]
        for root, dirnames, filenames in walk(d):
            for fn in filenames:
                if any([fn.endswith(ext) for ext in exts]):
                    unlink(join(root, fn))

    def install_python_package(self, name=None, env=None, is_dir=True):
        """Automate the installation of a Python package into the target
        site-packages.

        It will works with the first filtered_archs, and the name of the recipe.
        """
        arch = self.filtered_archs[0]
        if name is None:
            name = self.name
        if env is None:
            env = self.get_recipe_env(arch)
        print("Install {} into the site-packages".format(name))
        build_dir = self.get_build_dir(arch.arch)
        chdir(build_dir)
        hostpython = sh.Command(self.ctx.hostpython)
        iosbuild = join(build_dir, "iosbuild")
        shprint(hostpython, "setup.py", "install", "-O2",
                "--prefix", iosbuild,
                _env=env)
        dest_dir = join(self.ctx.site_packages_dir, name)
        self.remove_junk(iosbuild)
        if is_dir:
            if exists(dest_dir):
                shutil.rmtree(dest_dir)
            func = shutil.copytree
        else:
            func = shutil.copy
        func(
            join(iosbuild, "lib",
                 self.ctx.python_ver_dir, "site-packages", name),
            dest_dir)

    def reduce_python_package(self):
        """Feel free to remove things you don't want in the final
        site-packages.
        """
        pass


class CythonRecipe(PythonRecipe):
    pre_build_ext = False
    cythonize = True

    def cythonize_file(self, filename):
        if filename.startswith(self.build_dir):
            filename = filename[len(self.build_dir) + 1:]
        print("Cythonize {}".format(filename))
        cmd = sh.Command(join(self.ctx.root_dir, "tools", "cythonize.py"))
        shprint(cmd, filename)

    def cythonize_build(self):
        if not self.cythonize:
            return
        root_dir = self.build_dir
        for root, dirnames, filenames in walk(root_dir):
            for filename in fnmatch.filter(filenames, "*.pyx"):
                self.cythonize_file(join(root, filename))

    def biglink(self):
        dirs = []
        for root, dirnames, filenames in walk(self.build_dir):
            if fnmatch.filter(filenames, "*.so.libs"):
                dirs.append(root)
        cmd = sh.Command(join(self.ctx.root_dir, "tools", "biglink"))
        shprint(cmd, join(self.build_dir, "lib{}.a".format(self.name)), *dirs)

    def get_recipe_env(self, arch):
        env = super(CythonRecipe, self).get_recipe_env(arch)
        env["KIVYIOSROOT"] = self.ctx.root_dir
        env["IOSSDKROOT"] = arch.sysroot
        env["LDSHARED"] = join(self.ctx.root_dir, "tools", "liblink")
        env["ARM_LD"] = env["LD"]
        env["ARCH"] = arch.arch
        return env

    def build_arch(self, arch):
        build_env = self.get_recipe_env(arch)
        hostpython = sh.Command(self.ctx.hostpython)
        if self.pre_build_ext:
            try:
                shprint(hostpython, "setup.py", "build_ext", "-g",
                        _env=build_env)
            except:
                pass
        self.cythonize_build()
        shprint(hostpython, "setup.py", "build_ext", "-g",
                _env=build_env)
        self.biglink()


def build_recipes(names, ctx):
    # gather all the dependencies
    print("Want to build {}".format(names))
    graph = Graph()
    recipe_to_load = names
    recipe_loaded = []
    while names:
        name = recipe_to_load.pop(0)
        if name in recipe_loaded:
            continue
        try:
            recipe = Recipe.get_recipe(name, ctx)
        except ImportError:
            print("ERROR: No recipe named {}".format(name))
            sys.exit(1)
        graph.add(name, name)
        print("Loaded recipe {} (depends of {}, optional are {})".format(name,
            recipe.depends, recipe.optional_depends))
        for depend in recipe.depends:
            graph.add(name, depend)
            recipe_to_load += recipe.depends
        for depend in recipe.optional_depends:
            # in case of compilation after the initial one, take in account
            # of the already compiled recipes
            key = "{}.build_all".format(depend)
            if key in ctx.state:
                recipe_to_load.append(name)
                graph.add(name, depend)
            else:
                graph.add_optional(name, depend)
        recipe_loaded.append(name)

    build_order = list(graph.find_order())
    print("Build order is {}".format(build_order))
    recipes = [Recipe.get_recipe(name, ctx) for name in build_order]
    for recipe in recipes:
        recipe.init_with_ctx(ctx)
    for recipe in recipes:
        recipe.execute()


def ensure_dir(filename):
    if not exists(filename):
        makedirs(filename)


def update_pbxproj(filename):
    # list all the compiled recipes
    ctx = Context()
    pbx_libraries = []
    pbx_frameworks = []
    frameworks = []
    libraries = []
    sources = []
    for recipe in Recipe.list_recipes():
        key = "{}.build_all".format(recipe)
        if key not in ctx.state:
            continue
        recipe = Recipe.get_recipe(recipe, ctx)
        recipe.init_with_ctx(ctx)
        pbx_frameworks.extend(recipe.pbx_frameworks)
        pbx_libraries.extend(recipe.pbx_libraries)
        libraries.extend(recipe.dist_libraries)
        frameworks.extend(recipe.frameworks)
        if recipe.sources:
            sources.append(recipe.name)

    pbx_frameworks = list(set(pbx_frameworks))
    pbx_libraries = list(set(pbx_libraries))
    libraries = list(set(libraries))

    print("-" * 70)
    print("The project need to have:")
    print("iOS Frameworks: {}".format(pbx_frameworks))
    print("iOS Libraries: {}".format(pbx_libraries))
    print("iOS local Frameworks: {}".format(frameworks))
    print("Libraries: {}".format(libraries))
    print("Sources to link: {}".format(sources))

    print("-" * 70)
    print("Analysis of {}".format(filename))

    from mod_pbxproj import XcodeProject
    project = XcodeProject.Load(filename)
    sysroot = sh.xcrun("--sdk", "iphonesimulator", "--show-sdk-path").strip()

    group = project.get_or_create_group("Frameworks")
    g_classes = project.get_or_create_group("Classes")
    for framework in pbx_frameworks:
        framework_name = "{}.framework".format(framework)
        if framework_name in frameworks:
            print("Ensure {} is in the project (local)".format(framework))
            f_path = join(ctx.dist_dir, "frameworks", framework_name)
        else:
            print("Ensure {} is in the project (system)".format(framework))
            f_path = join(sysroot, "System", "Library", "Frameworks",
                          "{}.framework".format(framework))
        project.add_file_if_doesnt_exist(f_path, parent=group, tree="DEVELOPER_DIR")
    for library in pbx_libraries:
        print("Ensure {} is in the project".format(library))
        f_path = join(sysroot, "usr", "lib",
                      "{}.dylib".format(library))
        project.add_file_if_doesnt_exist(f_path, parent=group, tree="DEVELOPER_DIR")
    for library in libraries:
        print("Ensure {} is in the project".format(library))
        project.add_file_if_doesnt_exist(library, parent=group)
    for name in sources:
        print("Ensure {} sources are used".format(name))
        fn = join(ctx.dist_dir, "sources", name)
        project.add_folder(fn, parent=g_classes)


    if project.modified:
        project.backup()
        project.save()


if __name__ == "__main__":
    import argparse

    class ToolchainCL(object):
        def __init__(self):
            parser = argparse.ArgumentParser(
                    description="Tool for managing the iOS / Python toolchain",
                    usage="""toolchain <command> [<args>]

Available commands:
    build         Build a recipe (compile a library for the required target
                  architecture)
    clean         Clean the build of the specified recipe
    distclean     Clean the build and the result
    recipes       List all the available recipes
    status        List all the recipes and their build status

Xcode:
    create        Create a new xcode project
    update        Update an existing xcode project (frameworks, libraries..)
    launchimage   Create Launch images for your xcode project
    icon          Create Icons for your xcode project
    pip           Install a pip dependency into the distribution
""")
            parser.add_argument("command", help="Command to run")
            args = parser.parse_args(sys.argv[1:2])
            if not hasattr(self, args.command):
                print('Unrecognized command')
                parser.print_help()
                exit(1)
            getattr(self, args.command)()

        def build(self):
            ctx = Context()
            parser = argparse.ArgumentParser(
                    description="Build the toolchain")
            parser.add_argument("recipe", nargs="+", help="Recipe to compile")
            parser.add_argument("--arch", action="append",
                                help="Restrict compilation to this arch")
            parser.add_argument("--concurrency", type=int, default=ctx.num_cores,
                                help="number of concurrent build processes (where supported)")
            parser.add_argument("--no-pigz", action="store_true", default=not bool(ctx.use_pigz),
                                help="do not use pigz for gzip decompression")
            parser.add_argument("--no-pbzip2", action="store_true", default=not bool(ctx.use_pbzip2),
                                help="do not use pbzip2 for bzip2 decompression")
            args = parser.parse_args(sys.argv[2:])

            if args.arch:
                if len(args.arch) == 1:
                    archs = args.arch[0].split()
                else:
                    archs = args.arch
                available_archs = [arch.arch for arch in ctx.archs]
                for arch in archs[:]:
                    if arch not in available_archs:
                        print("ERROR: Architecture {} invalid".format(arch))
                        archs.remove(arch)
                        continue
                ctx.archs = [arch for arch in ctx.archs if arch.arch in archs]
                print("Architectures restricted to: {}".format(archs))
            ctx.num_cores = args.concurrency
            if args.no_pigz:
                ctx.use_pigz = False
            if args.no_pbzip2:
                ctx.use_pbzip2 = False
            ctx.use_pigz = ctx.use_pbzip2
            print("Building with {} processes, where supported".format(ctx.num_cores))
            if ctx.use_pigz:
                print("Using pigz to decompress gzip data")
            if ctx.use_pbzip2:
                print("Using pbzip2 to decompress bzip2 data")
            build_recipes(args.recipe, ctx)

        def recipes(self):
            parser = argparse.ArgumentParser(
                    description="List all the available recipes")
            parser.add_argument(
                    "--compact", action="store_true",
                    help="Produce a compact list suitable for scripting")
            args = parser.parse_args(sys.argv[2:])

            if args.compact:
                print(" ".join(list(Recipe.list_recipes())))
            else:
                ctx = Context()
                for name in Recipe.list_recipes():
                    recipe = Recipe.get_recipe(name, ctx)
                    print("{recipe.name:<12} {recipe.version:<8}".format(
                          recipe=recipe))

        def clean(self):
            parser = argparse.ArgumentParser(
                    description="Clean the build")
            parser.add_argument("recipe", nargs="*", help="Recipe to clean")
            args = parser.parse_args(sys.argv[2:])
            ctx = Context()
            if args.recipe:
                for recipe in args.recipe:
                    print("Cleaning {} build".format(recipe))
                    ctx.state.remove_all("{}.".format(recipe))
                    build_dir = join(ctx.build_dir, recipe)
                    if exists(build_dir):
                        shutil.rmtree(build_dir)
            else:
                print("Delete build directory")
                if exists(ctx.build_dir):
                    shutil.rmtree(ctx.build_dir)

        def distclean(self):
            parser = argparse.ArgumentParser(
                    description="Clean the build, download, and dist")
            args = parser.parse_args(sys.argv[2:])
            ctx = Context()
            if exists(ctx.build_dir):
                shutil.rmtree(ctx.build_dir)
            if exists(ctx.dist_dir):
                shutil.rmtree(ctx.dist_dir)
            if exists(ctx.cache_dir):
                shutil.rmtree(ctx.cache_dir)

        def status(self):
            parser = argparse.ArgumentParser(
                    description="Give a status of the build")
            args = parser.parse_args(sys.argv[2:])
            ctx = Context()
            for recipe in Recipe.list_recipes():
                key = "{}.build_all".format(recipe)
                keytime = "{}.build_all.at".format(recipe)

                if key in ctx.state:
                    status = "Build OK (built at {})".format(ctx.state[keytime])
                else:
                    status = "Not built"
                print("{:<12} - {}".format(
                    recipe, status))

        def create(self):
            parser = argparse.ArgumentParser(
                    description="Create a new xcode project")
            parser.add_argument("name", help="Name of your project")
            parser.add_argument("directory", help="Directory where your project lives")
            args = parser.parse_args(sys.argv[2:])

            from cookiecutter.main import cookiecutter
            ctx = Context()
            template_dir = join(curdir, "tools", "templates")
            context = {
                "title": args.name,
                "project_name": args.name.lower(),
                "domain_name": "org.kivy.{}".format(args.name.lower()),
                "kivy_dir": dirname(realpath(__file__)),
                "project_dir": realpath(args.directory),
                "version": "1.0.0",
                "dist_dir": ctx.dist_dir,
            }
            cookiecutter(template_dir, no_input=True, extra_context=context)
            filename = join(
                    getcwd(),
                    "{}-ios".format(args.name.lower()),
                    "{}.xcodeproj".format(args.name.lower()),
                    "project.pbxproj")
            update_pbxproj(filename)
            print("--")
            print("Project directory : {}-ios".format(
                args.name.lower()))
            print("XCode project     : {0}-ios/{0}.xcodeproj".format(
                args.name.lower()))

        def update(self):
            parser = argparse.ArgumentParser(
                    description="Update an existing xcode project")
            parser.add_argument("filename", help="Path to your project or xcodeproj")
            args = parser.parse_args(sys.argv[2:])

            filename = args.filename
            if not filename.endswith(".xcodeproj"):
                # try to find the xcodeproj
                from glob import glob
                xcodeproj = glob(join(filename, "*.xcodeproj"))
                if not xcodeproj:
                    print("ERROR: Unable to find a xcodeproj in {}".format(filename))
                    sys.exit(1)
                filename = xcodeproj[0]

            filename = join(filename, "project.pbxproj")
            if not exists(filename):
                print("ERROR: {} not found".format(filename))
                sys.exit(1)

            update_pbxproj(filename)
            print("--")
            print("Project {} updated".format(filename))

        def pip(self):
            ctx = Context()
            for recipe in Recipe.list_recipes():
                key = "{}.build_all".format(recipe)
                if key not in ctx.state:
                    continue
                recipe = Recipe.get_recipe(recipe, ctx)
                recipe.init_with_ctx(ctx)
            if not hasattr(ctx, "site_packages_dir"):
                print("ERROR: python must be compiled before using pip")
                sys.exit(1)

            pip_env = {
                "CC": "/bin/false",
                "CXX": "/bin/false",
                "PYTHONPATH": ctx.site_packages_dir,
                "PYTHONOPTIMIZE": "2",
                # "PIP_INSTALL_TARGET": ctx.site_packages_dir
            }
            pip_path = sh.which("pip2")
            pip_args = []
            if len(sys.argv) > 2 and sys.argv[2] == "install":
                pip_args = ["--isolated", "--prefix", ctx.python_prefix]
                args = [pip_path] + [sys.argv[2]] + pip_args + sys.argv[3:]
            else:
                args = [pip_path] + pip_args + sys.argv[2:]

            if not pip_path:
                print("ERROR: pip not found")
                sys.exit(1)
            import os
            print("-- execute pip with: {}".format(args))
            os.execve(pip_path, args, pip_env)

        def launchimage(self):
            import xcassets
            self._xcassets("LaunchImage", xcassets.launchimage)

        def icon(self):
            import xcassets
            self._xcassets("Icon", xcassets.icon)

        def xcode(self):
            parser = argparse.ArgumentParser(description="Open the xcode project")
            parser.add_argument("filename", help="Path to your project or xcodeproj")
            args = parser.parse_args(sys.argv[2:])
            filename = args.filename
            if not filename.endswith(".xcodeproj"):
                # try to find the xcodeproj
                from glob import glob
                xcodeproj = glob(join(filename, "*.xcodeproj"))
                if not xcodeproj:
                    print("ERROR: Unable to find a xcodeproj in {}".format(filename))
                    sys.exit(1)
                filename = xcodeproj[0]
            sh.open(filename)

        def _xcassets(self, title, command):
            parser = argparse.ArgumentParser(
                    description="Generate {} for your project".format(title))
            parser.add_argument("filename", help="Path to your project or xcodeproj")
            parser.add_argument("image", help="Path to your initial {}.png".format(title.lower()))
            args = parser.parse_args(sys.argv[2:])

            if not exists(args.image):
                print("ERROR: image path does not exists.")
                return

            filename = args.filename
            if not filename.endswith(".xcodeproj"):
                # try to find the xcodeproj
                from glob import glob
                xcodeproj = glob(join(filename, "*.xcodeproj"))
                if not xcodeproj:
                    print("ERROR: Unable to find a xcodeproj in {}".format(filename))
                    sys.exit(1)
                filename = xcodeproj[0]

            project_name = filename.split("/")[-1].replace(".xcodeproj", "")
            images_xcassets = realpath(join(filename, "..", project_name,
                "Images.xcassets"))
            if not exists(images_xcassets):
                print("WARNING: Images.xcassets not found, creating it.")
                makedirs(images_xcassets)
            print("Images.xcassets located at {}".format(images_xcassets))

            command(images_xcassets, args.image)

    ToolchainCL()
