"""
=====================
Triqs magic
=====================

{TRIQS_DOC}

"""
import imp,os,sys,subprocess, hashlib
from IPython.core.error import UsageError
from IPython.core.magic import Magics, magics_class, line_magic, cell_magic
from IPython.core import display, magic_arguments
from IPython.utils import py3compat
from IPython.utils.io import capture_output
from IPython.utils.path import get_ipython_cache_dir

__version__ = '0.1.0'

triqs_path = "@CMAKE_INSTALL_PREFIX@"
cxx_compiler = "@CMAKE_CXX_COMPILER@"
converter_include_path = triqs_path + "/include/pytriqs/converters/"
generator_path = triqs_path + "/share/triqs/wrap_generator"

cmakelist = """
list(APPEND CMAKE_MODULE_PATH %s/share/triqs/cmake)
cmake_minimum_required(VERSION 2.8)
project(triqs_magic CXX)
set(CMAKE_BUILD_TYPE Release)
option(BUILD_SHARED_LIBS "Build shared libraries" ON)
find_package(TRIQS REQUIRED)
include_directories(${CMAKE_SOURCE_DIR} ${TRIQS_INCLUDE_ALL})
add_library(ext MODULE ext_wrap.cpp)
#add_library(ext MODULE ext.cpp ext_wrap.cpp)
set_target_properties(ext PROPERTIES PREFIX "") #eliminate the lib in front of the module name
target_link_libraries(ext ${TRIQS_LIBRARY_ALL})
triqs_set_rpath_for_target(ext)
"""%triqs_path

mod_dict = {
 'gf' :
"""
module.use_module('gf')
module.add_using('namespace triqs::gfs')
""",
 'parameters' :
"""
module.use_module('parameters')
module.add_using('namespace triqs::params')
""",}

def desc_file(c_decl, use) :
   s = """
from wrap_generator import *
module = module_(full_name = "ext", doc = "")
module.add_include("<triqs/arrays.hpp>")
module.add_using("namespace triqs::arrays")
module.add_preamble('#include "./ext.cpp"')
"""

   mod_list = sum((x.split(',') for x in use), [])
   for m in mod_list :
       s+= mod_dict[m]

   for f in c_decl :
       s+= 'module.add_function("%s")\n'%f

   return s + "module.generate_code()\n"

@magics_class
class TriqsMagics(Magics):

    def __init__(self, shell):
        super(TriqsMagics, self).__init__(shell=shell)
        self._reloads = {}
        self._code_cache = {}
        self._lib_dir = os.path.join(get_ipython_cache_dir(), 'triqs')
        if not os.path.exists(self._lib_dir):
            os.makedirs(self._lib_dir)

    def _import_all(self, module, verbosity=0):
        imported = []
        for k, v in module.__dict__.items():
            if not k.startswith('__'):
                self.shell.push({k: v})
                imported.append(k)
        if verbosity > 0 and imported:
            print("\nOk. The following objects are ready to use: %s" % ", ".join(imported))

    def extract_signature(self,code):
        acc = []
        for l in code.splitlines() :
            ll = l.strip()
            if ll.startswith("#") or ll.startswith("using") : continue
            acc.append(l)
            if l.count('{') : break
        s = ''.join(acc).split('{',1)[0] # everything before {
        #print "signature", s
        return [s]

    @magic_arguments.magic_arguments()
    @magic_arguments.argument(
            "-v", "--verbosity", action="count", default=0,
            help="increase output verbosity"
        )
    @magic_arguments.argument(
            '-u', "--use", action='append', default=[],
            help="""Modules used"""
        )
    @cell_magic
    def triqs(self, line, cell=None):
        """Compile and import everything from a Triqs code cell.

        The content of the cell is written to a `.cpp` file in the
        directory `IPYTHONDIR/triqs` using a filename with the hash of the
        code. A python wrapper is then generated from the function signature.
        Those files are then compiled.
        The resulting module is imported and all of its symbols are injected into the user's namespace.

        Usage
        =====
        Prepend ``%%triqs`` to your triqs code in a cell::

        ``%%triqs

        ! put your code here.
        ``
        """
        try:
            # custom saved arguments
            saved_defaults = vars(
                magic_arguments.parse_argstring(self.triqs,
                                                self.shell.db['triqs']))
            self.triqs.parser.set_defaults(**saved_defaults)
        except KeyError:
            saved_defaults = {'verbosity': 0}

        if '-v' in line:
            self.triqs.parser.set_defaults(verbosity=0)

        args = magic_arguments.parse_argstring(self.triqs, line)

        code = cell if cell.endswith('\n') else cell + '\n'
        key = code, line, sys.version_info, sys.executable

        c_decl = self.extract_signature(code)
        if args.verbosity>1 :
          print "Found function of signature"
          for f in c_decl :
              print f

        module_name = "ext"
        module_dirname = os.path.join(self._lib_dir, "_triqs_magic_" + hashlib.md5(str(key).encode('utf-8')).hexdigest())
        module_path = os.path.join(module_dirname, 'ext.so')
        try :
            os.mkdir(module_dirname)
        except :
            pass
        #print "dir", module_dirname

        old_cwd = os.getcwd()
        try:
            os.chdir(module_dirname)

            with open('ext_desc.py', 'w') as f:
                f.write(desc_file(c_decl, args.use))

            with open('CMakeLists.txt', 'w') as f:
                f.write(cmakelist)

            with open('ext.cpp', 'w') as f:
                f.write(code)

            # Call the wrapper generator
            command_generator = """
            PYTHONPATH={generator_path} python ext_desc.py {generator_path}/wrapper.mako.cpp ext_wrap.cpp {generator_path}/py_converter_wrapper.mako.hpp conv.hpp {converter_include_path}
            """.format(**globals())

            try :
              out_generator = subprocess.check_output(command_generator, stderr=subprocess.STDOUT, shell=True)
            except subprocess.CalledProcessError as E :
               print '---------- Wrapper generator error -------\n' + E.output
               return

            if args.verbosity>0 : print "---------- Wrapper generator ------", out_generator

            # Call cmake
            #command_cmake = "CXX =" + cxx_compiler+ "  cmake . -DTRIQS_PATH=" + triqs_path
            command_cmake = "cmake .  -DCMAKE_CXX_COMPILER="+ cxx_compiler+ " -DTRIQS_PATH=" + triqs_path

            try :
              out_cmake = subprocess.check_output(command_cmake, stderr=subprocess.STDOUT, shell=True)
            except subprocess.CalledProcessError as E :
               print '----------  Cmake error -------\n' + E.output
               return

            if args.verbosity>0 : print "---------- Cmake ------", out_cmake

            # Call make
            command_make = "make -j2"

            try :
              out_make = subprocess.check_output(command_make, stderr=subprocess.STDOUT, shell=True)
            except subprocess.CalledProcessError as E :
               print '----------  Make error -------\n' + E.output
               return

            if args.verbosity>0 : print "---------- Make ------", out_make

        finally:
            os.chdir(old_cwd)

        self._code_cache[key] = module_path
        module = imp.load_dynamic(module_name, module_path)
        self._import_all(module, verbosity=args.verbosity)

__doc__ = __doc__.format(TRIQS_DOC=' ' * 8 + TriqsMagics.triqs.__doc__)

def load_ipython_extension(ip):
    """Load the extension in IPython."""
    ip.register_magics(TriqsMagics)