#!/usr/bin/env python3
import argparse
import itertools
import json
from dataclasses import dataclass
from pathlib import Path

THIS_DIR = Path(__file__).parent.resolve()


@dataclass
class Config:
    architecture: list[dict]
    os: list[dict]
    build_type: list[str]
    cmake_args: list[str]


"""
Generate a strategy matrix for GitHub Actions CI.

On each PR commit we will build a selection of Debian, RHEL, Ubuntu, MacOS, and
Windows configurations, while upon merge into the develop or release branches,
we will build all configurations, and test most of them.

We will further set additional CMake arguments as follows:
- All builds will have the `tests`, `werr`, and `xrpld` options.
- All builds will have the `wextra` option except for GCC 12 and Clang 16.
- All release builds will have the `assert` option.
- Certain Debian Bookworm configurations will change the reference fee, enable
  codecov, and enable voidstar in PRs.
"""


def generate_strategy_matrix(all: bool, config: Config) -> list:
    configurations = []
    for architecture, os, build_type, cmake_args in itertools.product(
        config.architecture, config.os, config.build_type, config.cmake_args
    ):
        # The default CMake target is 'all' for Linux and MacOS and 'install'
        # for Windows, but it can get overridden for certain configurations.
        cmake_target = "install" if os["distro_name"] == "windows" else "all"

        # We build and test all configurations by default, except for Windows in
        # Debug, because it is too slow, as well as when code coverage is
        # enabled as that mode already runs the tests.
        build_only = False
        if os["distro_name"] == "windows" and build_type == "Debug":
            build_only = True

        # Only generate a subset of configurations in PRs.
        if not all:
            # Debian:
            # - Bookworm using GCC 13: Release on linux/amd64, set the reference
            #   fee to 500.
            # - Bookworm using GCC 15: Debug on linux/amd64, enable code
            #   coverage (which will be done below).
            # - Bookworm using Clang 16: Debug on linux/arm64, enable voidstar.
            # - Bookworm using Clang 17: Release on linux/amd64, set the
            #   reference fee to 1000.
            # - Bookworm using Clang 20: Debug on linux/amd64.
            if os["distro_name"] == "debian":
                skip = True
                if os["distro_version"] == "bookworm":
                    if (
                        f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-13"
                        and build_type == "Release"
                        and architecture["platform"] == "linux/amd64"
                    ):
                        cmake_args = f"-DUNIT_TEST_REFERENCE_FEE=500 {cmake_args}"
                        skip = False
                    if (
                        f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-15"
                        and build_type == "Debug"
                        and architecture["platform"] == "linux/amd64"
                    ):
                        skip = False
                    if (
                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-16"
                        and build_type == "Debug"
                        and architecture["platform"] == "linux/arm64"
                    ):
                        cmake_args = f"-Dvoidstar=ON {cmake_args}"
                        skip = False
                    if (
                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-17"
                        and build_type == "Release"
                        and architecture["platform"] == "linux/amd64"
                    ):
                        cmake_args = f"-DUNIT_TEST_REFERENCE_FEE=1000 {cmake_args}"
                        skip = False
                    if (
                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-20"
                        and build_type == "Debug"
                        and architecture["platform"] == "linux/amd64"
                    ):
                        skip = False
                if skip:
                    continue

            # RHEL:
            # - 9 using GCC 12: Debug on linux/amd64.
            # - 10 using Clang: Release on linux/amd64.
            if os["distro_name"] == "rhel":
                skip = True
                if os["distro_version"] == "9":
                    if (
                        f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-12"
                        and build_type == "Debug"
                        and architecture["platform"] == "linux/amd64"
                    ):
                        skip = False
                elif os["distro_version"] == "10":
                    if (
                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-any"
                        and build_type == "Release"
                        and architecture["platform"] == "linux/amd64"
                    ):
                        skip = False
                if skip:
                    continue

            # Ubuntu:
            # - Jammy using GCC 12: Debug on linux/arm64.
            # - Noble using GCC 14: Release on linux/amd64.
            # - Noble using Clang 18: Debug on linux/amd64.
            # - Noble using Clang 19: Release on linux/arm64.
            if os["distro_name"] == "ubuntu":
                skip = True
                if os["distro_version"] == "jammy":
                    if (
                        f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-12"
                        and build_type == "Debug"
                        and architecture["platform"] == "linux/arm64"
                    ):
                        skip = False
                elif os["distro_version"] == "noble":
                    if (
                        f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-14"
                        and build_type == "Release"
                        and architecture["platform"] == "linux/amd64"
                    ):
                        skip = False
                    if (
                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-18"
                        and build_type == "Debug"
                        and architecture["platform"] == "linux/amd64"
                    ):
                        skip = False
                    if (
                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-19"
                        and build_type == "Release"
                        and architecture["platform"] == "linux/arm64"
                    ):
                        skip = False
                if skip:
                    continue

            # MacOS:
            # - Debug on macos/arm64.
            if os["distro_name"] == "macos" and not (
                build_type == "Debug" and architecture["platform"] == "macos/arm64"
            ):
                continue

            # Windows:
            # - Release on windows/amd64.
            if os["distro_name"] == "windows" and not (
                build_type == "Release" and architecture["platform"] == "windows/amd64"
            ):
                continue

        # Additional CMake arguments.
        cmake_args = f"{cmake_args} -Dtests=ON -Dwerr=ON -Dxrpld=ON"
        if not f"{os['compiler_name']}-{os['compiler_version']}" in [
            "gcc-12",
            "clang-16",
        ]:
            cmake_args = f"{cmake_args} -Dwextra=ON"
        if build_type == "Release":
            cmake_args = f"{cmake_args} -Dassert=ON"

        # We skip all RHEL on arm64 due to a build failure that needs further
        # investigation.
        if os["distro_name"] == "rhel" and architecture["platform"] == "linux/arm64":
            continue

        # We skip all clang 20+ on arm64 due to Boost build error.
        if (
            f"{os['compiler_name']}-{os['compiler_version']}"
            in ["clang-20", "clang-21"]
            and architecture["platform"] == "linux/arm64"
        ):
            continue

        # Enable code coverage for Debian Bookworm using GCC 15 in Debug on
        # linux/amd64
        if (
            f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-15"
            and build_type == "Debug"
            and architecture["platform"] == "linux/amd64"
        ):
            cmake_args = f"-Dcoverage=ON -Dcoverage_format=xml -DCODE_COVERAGE_VERBOSE=ON -DCMAKE_C_FLAGS=-O0 -DCMAKE_CXX_FLAGS=-O0 {cmake_args}"

        # Generate a unique name for the configuration, e.g. macos-arm64-debug
        # or debian-bookworm-gcc-12-amd64-release.
        config_name = os["distro_name"]
        if (n := os["distro_version"]) != "":
            config_name += f"-{n}"
        if (n := os["compiler_name"]) != "":
            config_name += f"-{n}"
        if (n := os["compiler_version"]) != "":
            config_name += f"-{n}"
        config_name += (
            f"-{architecture['platform'][architecture['platform'].find('/')+1:]}"
        )
        config_name += f"-{build_type.lower()}"
        if "-Dcoverage=ON" in cmake_args:
            config_name += "-coverage"

        # Add the configuration to the list, with the most unique fields first,
        # so that they are easier to identify in the GitHub Actions UI, as long
        # names get truncated.
        # Add Address and Thread (both coupled with UB) sanitizers for specific bookworm distros.
        # GCC-Asan rippled-embedded tests are failing because of https://github.com/google/sanitizers/issues/856
        if (
            os["distro_version"] == "bookworm"
            and f"{os['compiler_name']}-{os['compiler_version']}" == "clang-20"
        ):
            # Add ASAN + UBSAN configuration.
            configurations.append(
                {
                    "config_name": config_name + "-asan-ubsan",
                    "cmake_args": cmake_args,
                    "cmake_target": cmake_target,
                    "build_only": build_only,
                    "build_type": build_type,
                    "os": os,
                    "architecture": architecture,
                    "sanitizers": "address,undefinedbehavior",
                }
            )
            # TSAN is deactivated due to seg faults with latest compilers.
            activate_tsan = False
            if activate_tsan:
                configurations.append(
                    {
                        "config_name": config_name + "-tsan-ubsan",
                        "cmake_args": cmake_args,
                        "cmake_target": cmake_target,
                        "build_only": build_only,
                        "build_type": build_type,
                        "os": os,
                        "architecture": architecture,
                        "sanitizers": "thread,undefinedbehavior",
                    }
                )
        else:
            configurations.append(
                {
                    "config_name": config_name,
                    "cmake_args": cmake_args,
                    "cmake_target": cmake_target,
                    "build_only": build_only,
                    "build_type": build_type,
                    "os": os,
                    "architecture": architecture,
                    "sanitizers": "",
                }
            )

    return configurations


def read_config(file: Path) -> Config:
    config = json.loads(file.read_text())
    if (
        config["architecture"] is None
        or config["os"] is None
        or config["build_type"] is None
        or config["cmake_args"] is None
    ):
        raise Exception("Invalid configuration file.")

    return Config(**config)


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument(
        "-a",
        "--all",
        help="Set to generate all configurations (generally used when merging a PR) or leave unset to generate a subset of configurations (generally used when committing to a PR).",
        action="store_true",
    )
    parser.add_argument(
        "-c",
        "--config",
        help="Path to the JSON file containing the strategy matrix configurations.",
        required=False,
        type=Path,
    )
    args = parser.parse_args()

    matrix = []
    if args.config is None or args.config == "":
        matrix += generate_strategy_matrix(
            args.all, read_config(THIS_DIR / "linux.json")
        )
        matrix += generate_strategy_matrix(
            args.all, read_config(THIS_DIR / "macos.json")
        )
        matrix += generate_strategy_matrix(
            args.all, read_config(THIS_DIR / "windows.json")
        )
    else:
        matrix += generate_strategy_matrix(args.all, read_config(args.config))

    # Generate the strategy matrix.
    print(f"matrix={json.dumps({'include': matrix})}")