#!/usr/bin/env python3

import sys
import os
import itertools
import multiprocessing
from dataclasses import dataclass, field

from typing import Dict, List, Optional

CLANG_VERSION = 11


@dataclass
class Option:
    vars: Dict[str, str] = field(default_factory=dict)
    compiler: str = None
    config: str = None
    require: List[str] = field(default_factory=list)
    args: List[str] = field(default_factory=list)
    build: List[str] = field(default_factory=list)
    platform: str = None
    arch: str = None


OPTIONS = dict()


def merge_option(a: Option, b: Option) -> Option:

    res = Option(
        vars={**a.vars, **b.vars},
        require=a.require+b.require,
    )

    replace = (
        'args', 'build', 'platform', 'compiler', 'config', 'arch',
    )

    for f in replace:
        setattr(
            res,
            f,
            getattr(b, f, None) or getattr(a, f, None)
        )

    return res


###############################################################################
OPTIONS['gcc'] = Option(
    vars={
        'CMAKE_CXX_COMPILER': 'g++',
        'CMAKE_C_COMPILER': 'gcc'
    },
    compiler='gcc',
)

OPTIONS['clang'] = Option(
    vars={
        'CMAKE_CXX_COMPILER': f'clang++-{CLANG_VERSION}',
        'CMAKE_C_COMPILER': f'clang-{CLANG_VERSION}',
        #'CMAKE_CXX_FLAGS': '-fuse-ld=lld',
    },
    compiler='clang',
)


# -----------------------------------------------------------------------------
OPTIONS['debug'] = Option(
    vars={
        'CMAKE_BUILD_TYPE': 'Debug',
        'LTO': 'OFF'
    },
    config='debug',
    #'args': ['-G', '"Unix Makefiles"'],
    #'build': [ "make", f"-j{multiprocessing.cpu_count()}" ],
)


OPTIONS['release'] = Option(
    vars={
        'CMAKE_BUILD_TYPE': 'Release',
        'LTO': 'ON'
    },
    config='release',
)


OPTIONS['sanitizer'] = Option(
    vars={
        'SANITIZER': 'ON',
    },
    require=[
        'release'
    ],
)


# -----------------------------------------------------------------------------
OPTIONS['iwyu'] = Option(
    vars={
        'CMAKE_CXX_INCLUDE_WHAT_YOU_USE': 'include-what-you-use'
    }
)


TIDY_CHECKS=[
    'bugprone-*',
    'clang-analyzer-*',
    'performance-*',
    'portability-*',
    'readability-',
]


OPTIONS['tidy'] = Option(
    vars={
        'CMAKE_CXX_CLANG_TIDY': ';'.join([
            'clang-tidy',
            '--quiet',
            '-checks=' + ','.join(TIDY_CHECKS),
            '-warnings-as-errors=',
        ])
    }
)


# -----------------------------------------------------------------------------
OPTIONS['make'] = Option(
    args=[ '-G', '"Unix Makefiles"' ],
    build=[ "make", f"-j{multiprocessing.cpu_count()}" ]
)


OPTIONS['ninja'] = Option(
    args=['-G', 'Ninja'],
    build=['ninja']
)


# -----------------------------------------------------------------------------
OPTIONS['mingw'] = Option(
    vars={
        'CMAKE_TOOLCHAIN_FILE': os.path.join(
            os.path.dirname(__file__),
            'cmake', 'toolchain', 'mingw'
        )
    },
    compiler='gcc',
    platform='mingw',
)


# -----------------------------------------------------------------------------
OPTIONS['pi3'] = Option(
    vars={
        'CMAKE_TOOLCHAIN_FILE': os.path.join(
            os.path.dirname(__file__),
            'cmake', 'toolchain', 'armv7a-gcc'
        )
    },
    arch="armv7",
    compiler='gcc',
    platform='linux',
)


# -----------------------------------------------------------------------------
DEFAULT_OPTION = Option(
    vars={
        "CMAKE_EXPORT_COMPILE_COMMANDS": "ON",
        "TESTS": "ON",
    },

    args=['-G', 'Ninja'],

    build=[ 'ninja' ],

    platform='linux',
    compiler='gcc',
    config='release',
    arch='x86_64',
)


# #############################################################################
def split_all_path(path):
    parts = []

    while len(path) > 1:
        head,tail = os.path.split(path)
        yield tail
        path = head


# #############################################################################
if __name__ == '__main__':
    # Discover where we are, and where the source and build directories are
    self_path = os.path.realpath(__file__)
    self_dir = os.path.dirname(self_path)

    build_dir = os.path.realpath(os.getcwd())
    source_dir = os.path.dirname(self_dir)

    # Build a list of the OPTION keys we're going to combine
    accumulated = []

    components = []
    components += sys.argv[1:]
    components += itertools.takewhile(lambda x: x in OPTIONS, split_all_path(os.getcwd()))

    # Fold in the dependencies of each OPTION
    final_components = []
    for i in components:
        req = OPTIONS[i].require
        if req is not None:
            final_components.extend(req)
        final_components.append(i)
    components = final_components

    build = ['true']

    accum = DEFAULT_OPTION
    for i in components:
        accum = merge_option(accum, OPTIONS[i])

    accumulated = [f'"-D{key}={val}"' for key, val in accum.vars.items()] + accum.args

    conan_build_profile = 'x86_64-gcc-linux-release'
    conan_host_profile = '-'.join([
        accum.arch,
        accum.compiler,
        accum.platform,
        accum.config,
    ])

    if accum.platform == 'mingw':
        conan_build_profile = f'x86_64-gcc-linux-{accum.config}'

    profile_dir = os.path.join(source_dir, 'build', 'conan', 'profile')
    prh = os.path.join(profile_dir, conan_host_profile)
    prb = os.path.join(profile_dir, conan_build_profile)

    cmds = [
        f"{{ [[ -v VIRTUAL_ENV ]] || source {source_dir}/venv/bin/activate; }}",
        f"conan install {source_dir} -pr:h {prh} -pr:b {prb} --build=missing",
        f"conan install {source_dir} -pr:h {prh} -pr:b {prb} --build=missing -g deploy -if deps/",
        f"cmake {source_dir} {' '.join(accumulated)}",
        ' '.join(accum.build)
    ]

    print(" && ".join(cmds))