# Copyright 2017 The Meson development team

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at

#     http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""Code that creates simple startup projects."""

from ._pathlib import Path
from enum import Enum
import subprocess
import shutil
import sys
import os
import re
from glob import glob
from mesonbuild import mesonlib
from mesonbuild.environment import detect_ninja
from mesonbuild.templates.samplefactory import sameple_generator
import typing as T

if T.TYPE_CHECKING:
    import argparse

'''
we currently have one meson template at this time.
'''
from mesonbuild.templates.mesontemplates import create_meson_build

FORTRAN_SUFFIXES = {'.f', '.for', '.F', '.f90', '.F90'}
LANG_SUFFIXES = {'.c', '.cc', '.cpp', '.cs', '.cu', '.d', '.m', '.mm', '.rs', '.java'} | FORTRAN_SUFFIXES
LANG_SUPPORTED = {'c', 'cpp', 'cs', 'cuda', 'd', 'fortran', 'java', 'rust', 'objc', 'objcpp'}

DEFAULT_PROJECT = 'executable'
DEFAULT_VERSION = '0.1'
class DEFAULT_TYPES(Enum):
    EXE = 'executable'
    LIB = 'library'

INFO_MESSAGE = '''Sample project created. To build it run the
following commands:

meson setup builddir
meson compile -C builddir
'''


def create_sample(options: 'argparse.Namespace') -> None:
    '''
    Based on what arguments are passed we check for a match in language
    then check for project type and create new Meson samples project.
    '''
    sample_gen = sameple_generator(options)
    if options.type == DEFAULT_TYPES['EXE'].value:
        sample_gen.create_executable()
    elif options.type == DEFAULT_TYPES['LIB'].value:
        sample_gen.create_library()
    else:
        raise RuntimeError('Unreachable code')
    print(INFO_MESSAGE)

def autodetect_options(options: 'argparse.Namespace', sample: bool = False) -> None:
    '''
    Here we autodetect options for args not passed in so don't have to
    think about it.
    '''
    if not options.name:
        options.name = Path().resolve().stem
        if not re.match('[a-zA-Z_][a-zA-Z0-9]*', options.name) and sample:
            raise SystemExit('Name of current directory "{}" is not usable as a sample project name.\n'
                             'Specify a project name with --name.'.format(options.name))
        print('Using "{}" (name of current directory) as project name.'
              .format(options.name))
    if not options.executable:
        options.executable = options.name
        print('Using "{}" (project name) as name of executable to build.'
              .format(options.executable))
    if sample:
        # The rest of the autodetection is not applicable to generating sample projects.
        return
    if not options.srcfiles:
        srcfiles = []
        for f in (f for f in Path().iterdir() if f.is_file()):
            if f.suffix in LANG_SUFFIXES:
                srcfiles.append(f)
        if not srcfiles:
            raise SystemExit('No recognizable source files found.\n'
                             'Run meson init in an empty directory to create a sample project.')
        options.srcfiles = srcfiles
        print("Detected source files: " + ' '.join(map(str, srcfiles)))
    options.srcfiles = [Path(f) for f in options.srcfiles]
    if not options.language:
        for f in options.srcfiles:
            if f.suffix == '.c':
                options.language = 'c'
                break
            if f.suffix in ('.cc', '.cpp'):
                options.language = 'cpp'
                break
            if f.suffix in '.cs':
                options.language = 'cs'
                break
            if f.suffix == '.cu':
                options.language = 'cuda'
                break
            if f.suffix == '.d':
                options.language = 'd'
                break
            if f.suffix in FORTRAN_SUFFIXES:
                options.language = 'fortran'
                break
            if f.suffix == '.rs':
                options.language = 'rust'
                break
            if f.suffix == '.m':
                options.language = 'objc'
                break
            if f.suffix == '.mm':
                options.language = 'objcpp'
                break
            if f.suffix == '.java':
                options.language = 'java'
                break
        if not options.language:
            raise SystemExit("Can't autodetect language, please specify it with -l.")
        print("Detected language: " + options.language)

def add_arguments(parser: 'argparse.ArgumentParser') -> None:
    '''
    Here we add args for that the user can passed when making a new
    Meson project.
    '''
    parser.add_argument("srcfiles", metavar="sourcefile", nargs="*", help="source files. default: all recognized files in current directory")
    parser.add_argument('-C', default='.', dest='wd', help='directory to cd into before running')
    parser.add_argument("-n", "--name", help="project name. default: name of current directory")
    parser.add_argument("-e", "--executable", help="executable name. default: project name")
    parser.add_argument("-d", "--deps", help="dependencies, comma-separated")
    parser.add_argument("-l", "--language", choices=sorted(LANG_SUPPORTED), help="project language. default: autodetected based on source files")
    parser.add_argument("-b", "--build", action='store_true', help="build after generation")
    parser.add_argument("--builddir", default='build', help="directory for build")
    parser.add_argument("-f", "--force", action="store_true", help="force overwrite of existing files and directories.")
    parser.add_argument('--type', default=DEFAULT_PROJECT, choices=('executable', 'library'), help="project type. default: {} based project".format(DEFAULT_PROJECT))
    parser.add_argument('--version', default=DEFAULT_VERSION, help="project version. default: {}".format(DEFAULT_VERSION))

def run(options: 'argparse.Namespace') -> int:
    '''
    Here we generate the new Meson sample project.
    '''
    if not Path(options.wd).exists():
        sys.exit('Project source root directory not found. Run this command in source directory root.')
    os.chdir(options.wd)

    if not glob('*'):
        autodetect_options(options, sample=True)
        if not options.language:
            print('Defaulting to generating a C language project.')
            options.language = 'c'
        create_sample(options)
    else:
        autodetect_options(options)
        if Path('meson.build').is_file() and not options.force:
            raise SystemExit('meson.build already exists. Use --force to overwrite.')
        create_meson_build(options)
    if options.build:
        if Path(options.builddir).is_dir() and options.force:
            print('Build directory already exists, deleting it.')
            shutil.rmtree(options.builddir)
        print('Building...')
        cmd = mesonlib.meson_command + [options.builddir]
        ret = subprocess.run(cmd)
        if ret.returncode:
            raise SystemExit
        cmd = detect_ninja() + ['-C', options.builddir]
        ret = subprocess.run(cmd)
        if ret.returncode:
            raise SystemExit
    return 0