#!/usr/bin/env python
# encoding: utf-8
# Thomas Nagy, 2005-2018 (ita)

"""
Configuration system

A :py:class:`waflib.Configure.ConfigurationContext` instance is created when ``waf configure`` is called, it is used to:

* create data dictionaries (ConfigSet instances)
* store the list of modules to import
* hold configuration routines such as ``find_program``, etc
"""

import os, re, shlex, shutil, sys, time, traceback
from waflib import ConfigSet, Utils, Options, Logs, Context, Build, Errors

WAF_CONFIG_LOG = 'config.log'
"""Name of the configuration log file"""

autoconfig = False
"""Execute the configuration automatically"""

conf_template = '''# project %(app)s configured on %(now)s by
# waf %(wafver)s (abi %(abi)s, python %(pyver)x on %(systype)s)
# using %(args)s
#'''

class ConfigurationContext(Context.Context):
	'''configures the project'''

	cmd = 'configure'

	error_handlers = []
	"""
	Additional functions to handle configuration errors
	"""

	def __init__(self, **kw):
		super(ConfigurationContext, self).__init__(**kw)
		self.environ = dict(os.environ)
		self.all_envs = {}

		self.top_dir = None
		self.out_dir = None

		self.tools = [] # tools loaded in the configuration, and that will be loaded when building

		self.hash = 0
		self.files = []

		self.tool_cache = []

		self.setenv('')

	def setenv(self, name, env=None):
		"""
		Set a new config set for conf.env. If a config set of that name already exists,
		recall it without modification.

		The name is the filename prefix to save to ``c4che/NAME_cache.py``, and it
		is also used as *variants* by the build commands.
		Though related to variants, whatever kind of data may be stored in the config set::

			def configure(cfg):
				cfg.env.ONE = 1
				cfg.setenv('foo')
				cfg.env.ONE = 2

			def build(bld):
				2 == bld.env_of_name('foo').ONE

		:param name: name of the configuration set
		:type name: string
		:param env: ConfigSet to copy, or an empty ConfigSet is created
		:type env: :py:class:`waflib.ConfigSet.ConfigSet`
		"""
		if name not in self.all_envs or env:
			if not env:
				env = ConfigSet.ConfigSet()
				self.prepare_env(env)
			else:
				env = env.derive()
			self.all_envs[name] = env
		self.variant = name

	def get_env(self):
		"""Getter for the env property"""
		return self.all_envs[self.variant]
	def set_env(self, val):
		"""Setter for the env property"""
		self.all_envs[self.variant] = val

	env = property(get_env, set_env)

	def init_dirs(self):
		"""
		Initialize the project directory and the build directory
		"""

		top = self.top_dir
		if not top:
			top = Options.options.top
		if not top:
			top = getattr(Context.g_module, Context.TOP, None)
		if not top:
			top = self.path.abspath()
		top = os.path.abspath(top)

		self.srcnode = (os.path.isabs(top) and self.root or self.path).find_dir(top)
		assert(self.srcnode)

		out = self.out_dir
		if not out:
			out = Options.options.out
		if not out:
			out = getattr(Context.g_module, Context.OUT, None)
		if not out:
			out = Options.lockfile.replace('.lock-waf_%s_' % sys.platform, '').replace('.lock-waf', '')

		# someone can be messing with symlinks
		out = os.path.realpath(out)

		self.bldnode = (os.path.isabs(out) and self.root or self.path).make_node(out)
		self.bldnode.mkdir()

		if not os.path.isdir(self.bldnode.abspath()):
			self.fatal('Could not create the build directory %s' % self.bldnode.abspath())

	def execute(self):
		"""
		See :py:func:`waflib.Context.Context.execute`
		"""
		self.init_dirs()

		self.cachedir = self.bldnode.make_node(Build.CACHE_DIR)
		self.cachedir.mkdir()

		path = os.path.join(self.bldnode.abspath(), WAF_CONFIG_LOG)
		self.logger = Logs.make_logger(path, 'cfg')

		app = getattr(Context.g_module, 'APPNAME', '')
		if app:
			ver = getattr(Context.g_module, 'VERSION', '')
			if ver:
				app = "%s (%s)" % (app, ver)

		params = {'now': time.ctime(), 'pyver': sys.hexversion, 'systype': sys.platform, 'args': " ".join(sys.argv), 'wafver': Context.WAFVERSION, 'abi': Context.ABI, 'app': app}
		self.to_log(conf_template % params)
		self.msg('Setting top to', self.srcnode.abspath())
		self.msg('Setting out to', self.bldnode.abspath())

		if id(self.srcnode) == id(self.bldnode):
			Logs.warn('Setting top == out')
		elif id(self.path) != id(self.srcnode):
			if self.srcnode.is_child_of(self.path):
				Logs.warn('Are you certain that you do not want to set top="." ?')

		super(ConfigurationContext, self).execute()

		self.store()

		Context.top_dir = self.srcnode.abspath()
		Context.out_dir = self.bldnode.abspath()

		# this will write a configure lock so that subsequent builds will
		# consider the current path as the root directory (see prepare_impl).
		# to remove: use 'waf distclean'
		env = ConfigSet.ConfigSet()
		env.argv = sys.argv
		env.options = Options.options.__dict__
		env.config_cmd = self.cmd

		env.run_dir = Context.run_dir
		env.top_dir = Context.top_dir
		env.out_dir = Context.out_dir

		# conf.hash & conf.files hold wscript files paths and hash
		# (used only by Configure.autoconfig)
		env.hash = self.hash
		env.files = self.files
		env.environ = dict(self.environ)
		env.launch_dir = Context.launch_dir

		if not (self.env.NO_LOCK_IN_RUN or env.environ.get('NO_LOCK_IN_RUN') or getattr(Options.options, 'no_lock_in_run')):
			env.store(os.path.join(Context.run_dir, Options.lockfile))
		if not (self.env.NO_LOCK_IN_TOP or env.environ.get('NO_LOCK_IN_TOP') or getattr(Options.options, 'no_lock_in_top')):
			env.store(os.path.join(Context.top_dir, Options.lockfile))
		if not (self.env.NO_LOCK_IN_OUT or env.environ.get('NO_LOCK_IN_OUT') or getattr(Options.options, 'no_lock_in_out')):
			env.store(os.path.join(Context.out_dir, Options.lockfile))

	def prepare_env(self, env):
		"""
		Insert *PREFIX*, *BINDIR* and *LIBDIR* values into ``env``

		:type env: :py:class:`waflib.ConfigSet.ConfigSet`
		:param env: a ConfigSet, usually ``conf.env``
		"""
		if not env.PREFIX:
			if Options.options.prefix or Utils.is_win32:
				env.PREFIX = Options.options.prefix
			else:
				env.PREFIX = '/'
		if not env.BINDIR:
			if Options.options.bindir:
				env.BINDIR = Options.options.bindir
			else:
				env.BINDIR = Utils.subst_vars('${PREFIX}/bin', env)
		if not env.LIBDIR:
			if Options.options.libdir:
				env.LIBDIR = Options.options.libdir
			else:
				env.LIBDIR = Utils.subst_vars('${PREFIX}/lib%s' % Utils.lib64(), env)

	def store(self):
		"""Save the config results into the cache file"""
		n = self.cachedir.make_node('build.config.py')
		n.write('version = 0x%x\ntools = %r\n' % (Context.HEXVERSION, self.tools))

		if not self.all_envs:
			self.fatal('nothing to store in the configuration context!')

		for key in self.all_envs:
			tmpenv = self.all_envs[key]
			tmpenv.store(os.path.join(self.cachedir.abspath(), key + Build.CACHE_SUFFIX))

	def load(self, tool_list, tooldir=None, funs=None, with_sys_path=True, cache=False):
		"""
		Load Waf tools, which will be imported whenever a build is started.

		:param tool_list: waf tools to import
		:type tool_list: list of string
		:param tooldir: paths for the imports
		:type tooldir: list of string
		:param funs: functions to execute from the waf tools
		:type funs: list of string
		:param cache: whether to prevent the tool from running twice
		:type cache: bool
		"""

		tools = Utils.to_list(tool_list)
		if tooldir:
			tooldir = Utils.to_list(tooldir)
		for tool in tools:
			# avoid loading the same tool more than once with the same functions
			# used by composite projects

			if cache:
				mag = (tool, id(self.env), tooldir, funs)
				if mag in self.tool_cache:
					self.to_log('(tool %s is already loaded, skipping)' % tool)
					continue
				self.tool_cache.append(mag)

			module = None
			try:
				module = Context.load_tool(tool, tooldir, ctx=self, with_sys_path=with_sys_path)
			except ImportError as e:
				self.fatal('Could not load the Waf tool %r from %r\n%s' % (tool, getattr(e, 'waf_sys_path', sys.path), e))
			except Exception as e:
				self.to_log('imp %r (%r & %r)' % (tool, tooldir, funs))
				self.to_log(traceback.format_exc())
				raise

			if funs is not None:
				self.eval_rules(funs)
			else:
				func = getattr(module, 'configure', None)
				if func:
					if type(func) is type(Utils.readf):
						func(self)
					else:
						self.eval_rules(func)

			self.tools.append({'tool':tool, 'tooldir':tooldir, 'funs':funs})

	def post_recurse(self, node):
		"""
		Records the path and a hash of the scripts visited, see :py:meth:`waflib.Context.Context.post_recurse`

		:param node: script
		:type node: :py:class:`waflib.Node.Node`
		"""
		super(ConfigurationContext, self).post_recurse(node)
		self.hash = Utils.h_list((self.hash, node.read('rb')))
		self.files.append(node.abspath())

	def eval_rules(self, rules):
		"""
		Execute configuration tests provided as list of functions to run

		:param rules: list of configuration method names
		:type rules: list of string
		"""
		self.rules = Utils.to_list(rules)
		for x in self.rules:
			f = getattr(self, x)
			if not f:
				self.fatal('No such configuration function %r' % x)
			f()

def conf(f):
	"""
	Decorator: attach new configuration functions to :py:class:`waflib.Build.BuildContext` and
	:py:class:`waflib.Configure.ConfigurationContext`. The methods bound will accept a parameter
	named 'mandatory' to disable the configuration errors::

		def configure(conf):
			conf.find_program('abc', mandatory=False)

	:param f: method to bind
	:type f: function
	"""
	def fun(*k, **kw):
		mandatory = kw.pop('mandatory', True)
		try:
			return f(*k, **kw)
		except Errors.ConfigurationError:
			if mandatory:
				raise

	fun.__name__ = f.__name__
	setattr(ConfigurationContext, f.__name__, fun)
	setattr(Build.BuildContext, f.__name__, fun)
	return f

@conf
def add_os_flags(self, var, dest=None, dup=False):
	"""
	Import operating system environment values into ``conf.env`` dict::

		def configure(conf):
			conf.add_os_flags('CFLAGS')

	:param var: variable to use
	:type var: string
	:param dest: destination variable, by default the same as var
	:type dest: string
	:param dup: add the same set of flags again
	:type dup: bool
	"""
	try:
		flags = shlex.split(self.environ[var])
	except KeyError:
		return
	if dup or ''.join(flags) not in ''.join(Utils.to_list(self.env[dest or var])):
		self.env.append_value(dest or var, flags)

@conf
def cmd_to_list(self, cmd):
	"""
	Detect if a command is written in pseudo shell like ``ccache g++`` and return a list.

	:param cmd: command
	:type cmd: a string or a list of string
	"""
	if isinstance(cmd, str):
		if os.path.isfile(cmd):
			# do not take any risk
			return [cmd]
		if os.sep == '/':
			return shlex.split(cmd)
		else:
			try:
				return shlex.split(cmd, posix=False)
			except TypeError:
				# Python 2.5 on windows?
				return shlex.split(cmd)
	return cmd

@conf
def check_waf_version(self, mini='1.9.99', maxi='2.1.0', **kw):
	"""
	Raise a Configuration error if the Waf version does not strictly match the given bounds::

		conf.check_waf_version(mini='1.9.99', maxi='2.1.0')

	:type  mini: number, tuple or string
	:param mini: Minimum required version
	:type  maxi: number, tuple or string
	:param maxi: Maximum allowed version
	"""
	self.start_msg('Checking for waf version in %s-%s' % (str(mini), str(maxi)), **kw)
	ver = Context.HEXVERSION
	if Utils.num2ver(mini) > ver:
		self.fatal('waf version should be at least %r (%r found)' % (Utils.num2ver(mini), ver))
	if Utils.num2ver(maxi) < ver:
		self.fatal('waf version should be at most %r (%r found)' % (Utils.num2ver(maxi), ver))
	self.end_msg('ok', **kw)

@conf
def find_file(self, filename, path_list=[]):
	"""
	Find a file in a list of paths

	:param filename: name of the file to search for
	:param path_list: list of directories to search
	:return: the first matching filename; else a configuration exception is raised
	"""
	for n in Utils.to_list(filename):
		for d in Utils.to_list(path_list):
			p = os.path.expanduser(os.path.join(d, n))
			if os.path.exists(p):
				return p
	self.fatal('Could not find %r' % filename)

@conf
def find_program(self, filename, **kw):
	"""
	Search for a program on the operating system

	When var is used, you may set os.environ[var] to help find a specific program version, for example::

		$ CC='ccache gcc' waf configure

	:param path_list: paths to use for searching
	:type param_list: list of string
	:param var: store the result to conf.env[var] where var defaults to filename.upper() if not provided; the result is stored as a list of strings
	:type var: string
	:param value: obtain the program from the value passed exclusively
	:type value: list or string (list is preferred)
	:param exts: list of extensions for the binary (do not add an extension for portability)
	:type exts: list of string
	:param msg: name to display in the log, by default filename is used
	:type msg: string
	:param interpreter: interpreter for the program
	:type interpreter: ConfigSet variable key
	:raises: :py:class:`waflib.Errors.ConfigurationError`
	"""

	exts = kw.get('exts', Utils.is_win32 and '.exe,.com,.bat,.cmd' or ',.sh,.pl,.py')

	environ = kw.get('environ', getattr(self, 'environ', os.environ))

	ret = ''

	filename = Utils.to_list(filename)
	msg = kw.get('msg', ', '.join(filename))

	var = kw.get('var', '')
	if not var:
		var = re.sub(r'\W', '_', filename[0].upper())

	path_list = kw.get('path_list', '')
	if path_list:
		path_list = Utils.to_list(path_list)
	else:
		path_list = environ.get('PATH', '').split(os.pathsep)

	if kw.get('value'):
		# user-provided in command-line options and passed to find_program
		ret = self.cmd_to_list(kw['value'])
	elif environ.get(var):
		# user-provided in the os environment
		ret = self.cmd_to_list(environ[var])
	elif self.env[var]:
		# a default option in the wscript file
		ret = self.cmd_to_list(self.env[var])
	else:
		if not ret:
			ret = self.find_binary(filename, exts.split(','), path_list)
		if not ret and Utils.winreg:
			ret = Utils.get_registry_app_path(Utils.winreg.HKEY_CURRENT_USER, filename)
		if not ret and Utils.winreg:
			ret = Utils.get_registry_app_path(Utils.winreg.HKEY_LOCAL_MACHINE, filename)
		ret = self.cmd_to_list(ret)

	if ret:
		if len(ret) == 1:
			retmsg = ret[0]
		else:
			retmsg = ret
	else:
		retmsg = False

	self.msg('Checking for program %r' % msg, retmsg, **kw)
	if not kw.get('quiet'):
		self.to_log('find program=%r paths=%r var=%r -> %r' % (filename, path_list, var, ret))

	if not ret:
		self.fatal(kw.get('errmsg', '') or 'Could not find the program %r' % filename)

	interpreter = kw.get('interpreter')
	if interpreter is None:
		if not Utils.check_exe(ret[0], env=environ):
			self.fatal('Program %r is not executable' % ret)
		self.env[var] = ret
	else:
		self.env[var] = self.env[interpreter] + ret

	return ret

@conf
def find_binary(self, filenames, exts, paths):
	for f in filenames:
		for ext in exts:
			exe_name = f + ext
			if os.path.isabs(exe_name):
				if os.path.isfile(exe_name):
					return exe_name
			else:
				for path in paths:
					x = os.path.expanduser(os.path.join(path, exe_name))
					if os.path.isfile(x):
						return x
	return None

@conf
def run_build(self, *k, **kw):
	"""
	Create a temporary build context to execute a build. A temporary reference to that build
	context is kept on self.test_bld for debugging purposes.
	The arguments to this function are passed to a single task generator for that build.
	Only three parameters are mandatory:

	:param features: features to pass to a task generator created in the build
	:type features: list of string
	:param compile_filename: file to create for the compilation (default: *test.c*)
	:type compile_filename: string
	:param code: input file contents
	:type code: string

	Though this function returns *0* by default, the build may bind attribute named *retval* on the
	build context object to return a particular value. See :py:func:`waflib.Tools.c_config.test_exec_fun` for example.

	The temporary builds creates a temporary folder; the name of that folder is calculated
	by hashing input arguments to this function, with the exception of :py:class:`waflib.ConfigSet.ConfigSet`
	objects which are used for both reading and writing values.

	This function also features a cache which is disabled by default; that cache relies
	on the hash value calculated as indicated above::

		def options(opt):
			opt.add_option('--confcache', dest='confcache', default=0,
				action='count', help='Use a configuration cache')

	And execute the configuration with the following command-line::

		$ waf configure --confcache

	"""
	buf = []
	for key in sorted(kw.keys()):
		v = kw[key]
		if isinstance(v, ConfigSet.ConfigSet):
			# values are being written to, so they are excluded from contributing to the hash
			continue
		elif hasattr(v, '__call__'):
			buf.append(Utils.h_fun(v))
		else:
			buf.append(str(v))
	h = Utils.h_list(buf)
	dir = self.bldnode.abspath() + os.sep + (not Utils.is_win32 and '.' or '') + 'conf_check_' + Utils.to_hex(h)

	cachemode = kw.get('confcache', getattr(Options.options, 'confcache', None))

	if not cachemode and os.path.exists(dir):
		shutil.rmtree(dir)

	try:
		os.makedirs(dir)
	except OSError:
		pass

	try:
		os.stat(dir)
	except OSError:
		self.fatal('cannot use the configuration test folder %r' % dir)

	if cachemode == 1:
		try:
			proj = ConfigSet.ConfigSet(os.path.join(dir, 'cache_run_build'))
		except EnvironmentError:
			pass
		else:
			ret = proj['cache_run_build']
			if isinstance(ret, str) and ret.startswith('Test does not build'):
				self.fatal(ret)
			return ret

	bdir = os.path.join(dir, 'testbuild')

	if not os.path.exists(bdir):
		os.makedirs(bdir)

	cls_name = kw.get('run_build_cls') or getattr(self, 'run_build_cls', 'build')
	self.test_bld = bld = Context.create_context(cls_name, top_dir=dir, out_dir=bdir)
	bld.init_dirs()
	bld.progress_bar = 0
	bld.targets = '*'

	bld.logger = self.logger
	bld.all_envs.update(self.all_envs) # not really necessary
	bld.env = kw['env']

	bld.kw = kw
	bld.conf = self
	kw['build_fun'](bld)
	ret = -1
	try:
		try:
			bld.compile()
		except Errors.WafError:
			ret = 'Test does not build: %s' % traceback.format_exc()
			self.fatal(ret)
		else:
			ret = getattr(bld, 'retval', 0)
	finally:
		if cachemode:
			# cache the results each time
			proj = ConfigSet.ConfigSet()
			proj['cache_run_build'] = ret
			proj.store(os.path.join(dir, 'cache_run_build'))
		else:
			shutil.rmtree(dir)
	return ret

@conf
def ret_msg(self, msg, args):
	if isinstance(msg, str):
		return msg
	return msg(args)

@conf
def test(self, *k, **kw):

	if not 'env' in kw:
		kw['env'] = self.env.derive()

	# validate_c for example
	if kw.get('validate'):
		kw['validate'](kw)

	self.start_msg(kw['msg'], **kw)
	ret = None
	try:
		ret = self.run_build(*k, **kw)
	except self.errors.ConfigurationError:
		self.end_msg(kw['errmsg'], 'YELLOW', **kw)
		if Logs.verbose > 1:
			raise
		else:
			self.fatal('The configuration failed')
	else:
		kw['success'] = ret

	if kw.get('post_check'):
		ret = kw['post_check'](kw)

	if ret:
		self.end_msg(kw['errmsg'], 'YELLOW', **kw)
		self.fatal('The configuration failed %r' % ret)
	else:
		self.end_msg(self.ret_msg(kw['okmsg'], kw), **kw)
	return ret

