#!/usr/bin/env python3

# Copyright (c) 2025, ayeteadoe <ayeteadoe@gmail.com>
# Copyright (c) 2025, Tim Flynn <trflynn89@ladybird.org>
# Copyright (c) 2025, Nicolas Danelon <nicolasdanelon@gmail.com>
#
# SPDX-License-Identifier: BSD-2-Clause

import argparse
import os
import platform
import re
import shutil
import sys

from pathlib import Path
from typing import Optional

sys.path.append(str(Path(__file__).resolve().parent.parent))

from Meta.find_compiler import pick_host_compiler
from Meta.host_platform import HostArchitecture
from Meta.host_platform import HostSystem
from Meta.host_platform import Platform
from Meta.utils import run_command
from Toolchain.BuildVcpkg import build_vcpkg


def main():
    platform = Platform()
    (default_cc, default_cxx) = platform.default_compiler()

    parser = argparse.ArgumentParser(description="Ladybird")
    subparsers = parser.add_subparsers(dest="command")

    preset_parser = argparse.ArgumentParser(add_help=False)
    preset_parser.add_argument(
        "--preset",
        required=False,
        default=os.environ.get(
            "BUILD_PRESET", "windows_dev_ninja" if platform.host_system == HostSystem.Windows else "default"
        ),
    )

    compiler_parser = argparse.ArgumentParser(add_help=False)
    compiler_parser.add_argument("--cc", required=False, default=default_cc)
    compiler_parser.add_argument("--cxx", required=False, default=default_cxx)
    compiler_parser.add_argument("--jobs", "-j", required=False)

    target_parser = argparse.ArgumentParser(add_help=False)
    target_parser.add_argument("target", nargs=argparse.OPTIONAL)

    build_parser = subparsers.add_parser(
        "build", help="Compiles the target binaries", parents=[preset_parser, compiler_parser, target_parser]
    )
    build_parser.add_argument(
        "args", nargs=argparse.REMAINDER, help="Additional arguments passed through to the build system"
    )

    test_parser = subparsers.add_parser(
        "test", help="Runs the unit tests on the build host", parents=[preset_parser, compiler_parser]
    )
    test_parser.add_argument(
        "pattern", nargs=argparse.OPTIONAL, help="Limits the tests that are run to those that match the regex pattern"
    )

    run_parser = subparsers.add_parser(
        "run", help="Runs the application on the build host", parents=[preset_parser, compiler_parser, target_parser]
    )
    run_parser.add_argument(
        "args", nargs=argparse.REMAINDER, help="Additional arguments passed through to the application"
    )

    debug_parser = subparsers.add_parser(
        "debug",
        help="Launches the application on the build host in a gdb or lldb session",
        parents=[preset_parser, compiler_parser, target_parser],
    )
    debug_parser.add_argument("--debugger", required=False, default=platform.default_debugger())
    debug_parser.add_argument(
        "-cmd", action="append", required=False, default=[], help="Additional commands passed through to the debugger"
    )
    debug_parser.add_argument(
        "args", nargs=argparse.REMAINDER, help="Additional arguments passed through to the build system"
    )

    install_parser = subparsers.add_parser(
        "install", help="Installs the target binary", parents=[preset_parser, compiler_parser, target_parser]
    )

    install_parser.add_argument(
        "args", nargs=argparse.REMAINDER, help="Additional arguments passed through to the build system"
    )

    subparsers.add_parser("vcpkg", help="Ensure that dependencies are available", parents=[preset_parser])

    subparsers.add_parser("clean", help="Cleans the build environment", parents=[preset_parser])

    rebuild_parser = subparsers.add_parser(
        "rebuild",
        help="Cleans the build environment and compiles the target binaries",
        parents=[preset_parser, compiler_parser, target_parser],
    )
    rebuild_parser.add_argument(
        "args", nargs=argparse.REMAINDER, help="Additional arguments passed through to the build system"
    )

    addr2line_parser = subparsers.add_parser(
        "addr2line",
        help="Resolves the addresses in the target binary to a file:line",
        parents=[preset_parser, compiler_parser, target_parser],
    )
    addr2line_parser.add_argument("--program", required=False, default=platform.default_symbolizer())
    addr2line_parser.add_argument("addresses", nargs=argparse.REMAINDER)

    args = parser.parse_args()

    if not args.command:
        parser.print_help()
        sys.exit(1)

    if platform.host_system != HostSystem.Windows and os.geteuid() == 0:
        print("Do not run ladybird.py as root, your Build directory will become root-owned", file=sys.stderr)
        sys.exit(1)
    elif platform.host_system == HostSystem.Windows and "VCINSTALLDIR" not in os.environ:
        print("ladybird.py must be run from a Visual Studio enabled environment", file=sys.stderr)
        sys.exit(1)

    if "target" in args:
        if args.target == "ladybird":
            args.target = "Ladybird"
        if not args.target and args.command not in ("build", "rebuild"):
            args.target = "Ladybird"

    if args.command == "build":
        build_dir = configure_main(platform, args.preset, args.cc, args.cxx)
        build_main(build_dir, args.jobs, args.target, args.args)
    elif args.command == "test":
        build_dir = configure_main(platform, args.preset, args.cc, args.cxx)
        build_main(build_dir, args.jobs)
        test_main(build_dir, args.preset, args.pattern)
    elif args.command == "run":
        if args.preset == "Sanitizer":
            # FIXME: Find some way to centralize these b/w CMakePresets.json, CI files, Documentation and here.
            os.environ["ASAN_OPTIONS"] = os.environ.get(
                "ASAN_OPTIONS",
                "strict_string_checks=1:check_initialization_order=1:strict_init_order=1:"
                "detect_stack_use_after_return=1:allocator_may_return_null=1",
            )
            os.environ["UBSAN_OPTIONS"] = os.environ.get(
                "UBSAN_OPTIONS", "print_stacktrace=1:print_summary=1:halt_on_error=1"
            )
        build_dir = configure_main(platform, args.preset, args.cc, args.cxx)
        build_main(build_dir, args.jobs, args.target)
        run_main(platform.host_system, build_dir, args.target, args.args)
    elif args.command == "debug":
        build_dir = configure_main(platform, args.preset, args.cc, args.cxx)
        build_main(build_dir, args.jobs, args.target, args.args)
        debug_main(platform.host_system, build_dir, args.target, args.debugger, args.cmd)
    elif args.command == "install":
        build_dir = configure_main(platform, args.preset, args.cc, args.cxx)
        build_main(build_dir, args.jobs, args.target, args.args)
        build_main(build_dir, args.jobs, "install", args.args)
    elif args.command == "vcpkg":
        configure_build_env(args.preset)
        build_vcpkg()
    elif args.command == "clean":
        clean_main(args.preset)
    elif args.command == "rebuild":
        clean_main(args.preset)
        build_dir = configure_main(platform, args.preset, args.cc, args.cxx)
        build_main(build_dir, args.jobs, args.target, args.args)
    elif args.command == "addr2line":
        build_dir = configure_main(platform, args.preset, args.cc, args.cxx)
        build_main(build_dir, args.jobs, args.target)
        addr2line_main(build_dir, args.target, args.program, args.addresses)


def configure_main(platform: Platform, preset: str, cc: str, cxx: str) -> Path:
    ladybird_source_dir, build_preset_dir = configure_build_env(preset)
    build_vcpkg()

    if build_preset_dir.joinpath("build.ninja").exists() or build_preset_dir.joinpath("ladybird.sln").exists():
        return build_preset_dir

    validate_cmake_version()
    (cc, cxx) = pick_host_compiler(platform, cc, cxx)

    config_args = [
        "cmake",
        "--preset",
        preset,
        "-S",
        ladybird_source_dir,
        "-B",
        build_preset_dir,
        f"-DCMAKE_C_COMPILER={cc}",
        f"-DCMAKE_CXX_COMPILER={cxx}",
    ]

    if platform.host_system == HostSystem.Linux and platform.host_architecture == HostArchitecture.AArch64:
        config_args.extend(configure_skia_jemalloc())

    # FIXME: Improve error reporting for vcpkg install failures
    # https://github.com/LadybirdBrowser/ladybird/blob/master/Documentation/BuildInstructionsLadybird.md#unable-to-find-a-build-program-corresponding-to-ninja
    run_command(config_args, exit_on_failure=True)

    return build_preset_dir


def configure_skia_jemalloc() -> list[str]:
    # NOTE: The resource module is only available on Unix, see the "Availability" section at
    # https://docs.python.org/3/library/resource.html. Given Windows never calls this function, we import locally
    # instead.
    import resource

    page_size = resource.getpagesize()
    gn = shutil.which("gn") or None

    # https://github.com/LadybirdBrowser/ladybird/issues/261
    if page_size != 4096 and gn is None:
        print("GN not found! Please build GN from source and put it in $PATH", file=sys.stderr)
        sys.exit(1)

    cmake_args = []
    pkg_config = shutil.which("pkg-config") or None

    if pkg_config:
        cmake_args.append(f"-DPKG_CONFIG_EXECUTABLE={pkg_config}")

    user_vars_cmake_module = Path("Meta", "CMake", "vcpkg", "user-variables.cmake")
    user_vars_cmake_module.parent.mkdir(parents=True, exist_ok=True)

    with open(user_vars_cmake_module, "w") as f:
        f.writelines(
            [
                f"set(PKGCONFIG {pkg_config})",
                f"set(GN {gn})",
                "",
            ]
        )

    return cmake_args


def configure_build_env(preset: str) -> tuple[Path, Path]:
    ladybird_source_dir = ensure_ladybird_source_dir()
    build_root_dir = ladybird_source_dir / "Build"

    known_presets = {
        "default": build_root_dir / "release",
        "Debug": build_root_dir / "debug",
        "Distribution": build_root_dir / "distribution",
        "Sanitizer": build_root_dir / "sanitizers",
        "windows_ci_ninja": build_root_dir / "release",
        "windows_dev_ninja": build_root_dir / "debug",
    }

    build_preset_dir = known_presets.get(preset, None)
    if not build_preset_dir:
        print(f'Unknown build preset "{preset}"', file=sys.stderr)
        sys.exit(1)

    vcpkg_root = str(build_root_dir / "vcpkg")
    os.environ["PATH"] += os.pathsep + str(ladybird_source_dir.joinpath("Toolchain", "Local", "cmake", "bin"))
    os.environ["PATH"] += os.pathsep + vcpkg_root
    os.environ["VCPKG_ROOT"] = vcpkg_root

    return ladybird_source_dir, build_preset_dir


def validate_cmake_version():
    # FIXME: This 3.25+ CMake version check may not be needed anymore due to vcpkg downloading a newer version
    cmake_install_message = "Please install CMake version 3.25 or newer."

    cmake_version_output = run_command(["cmake", "--version"], return_output=True, exit_on_failure=True)
    assert cmake_version_output

    version_match = re.search(r"version\s+(\d+)\.(\d+)\.(\d+)?", cmake_version_output)
    if not version_match:
        print(f"Unable to determine CMake version. {cmake_install_message}", file=sys.stderr)
        sys.exit(1)

    major = int(version_match.group(1))
    minor = int(version_match.group(2))
    patch = int(version_match.group(3))

    if major < 3 or (major == 3 and minor < 25):
        print(f"CMake version {major}.{minor}.{patch} is too old. {cmake_install_message}", file=sys.stderr)
        sys.exit(1)


def ensure_ladybird_source_dir() -> Path:
    ladybird_source_dir = os.environ.get("LADYBIRD_SOURCE_DIR", None)
    ladybird_source_dir = Path(ladybird_source_dir) if ladybird_source_dir else None

    if not ladybird_source_dir or not ladybird_source_dir.is_dir():
        root_dir = run_command(["git", "rev-parse", "--show-toplevel"], return_output=True, exit_on_failure=True)
        assert root_dir

        os.environ["LADYBIRD_SOURCE_DIR"] = root_dir
        ladybird_source_dir = Path(root_dir)

    return ladybird_source_dir


def build_main(build_dir: Path, jobs: str | None, target: Optional[str] = None, args: list[str] = []):
    build_args = ["ninja", "-C", str(build_dir)]

    if not jobs:
        jobs = os.environ.get("MAKEJOBS", None)
    if jobs:
        build_args.extend(["-j", jobs])

    if target:
        build_args.append(target)

    if args:
        build_args.append("--")
        build_args.extend(args)

    run_command(build_args, exit_on_failure=True)


def test_main(build_dir: Path, preset: str, pattern: Optional[str]):
    test_args = [
        "ctest",
        "--preset",
        preset,
        "--output-on-failure",
        "--test-dir",
        str(build_dir),
    ]

    if pattern:
        test_args.extend(["-R", pattern])

    run_command(test_args, exit_on_failure=True)


def run_main(host_system: HostSystem, build_dir: Path, target: str, args: list[str]):
    run_args = []

    if host_system == HostSystem.macOS and target in (
        "headless-browser",
        "ImageDecoder",
        "Ladybird",
        "RequestServer",
        "WebContent",
        "WebDriver",
        "WebWorker",
    ):
        run_args.append(str(build_dir.joinpath("bin", "Ladybird.app", "Contents", "MacOS", target)))
    else:
        run_args.append(str(build_dir.joinpath("bin", target)))

    run_args.extend(args)

    run_command(run_args, exit_on_failure=True)


def debug_main(host_system: HostSystem, build_dir: Path, target: str, debugger: str, debugger_commands: list[str]):
    debuggers = ["gdb", "lldb"]
    if debugger not in debuggers or not shutil.which(debugger):
        print("Please install gdb or lldb!", file=sys.stderr)
        sys.exit(1)

    gdb_args = [debugger]
    for cmd in debugger_commands:
        gdb_args.extend(["-ex" if debugger == "gdb" else "-o", cmd])

    if target == "Ladybird" and host_system == HostSystem.macOS:
        gdb_args.append(str(build_dir.joinpath("bin", "Ladybird.app")))
    else:
        gdb_args.append(str(build_dir.joinpath("bin", target)))

    run_command(gdb_args, exit_on_failure=True)


def clean_main(preset: str):
    ladybird_source_dir, build_preset_dir = configure_build_env(preset)
    shutil.rmtree(str(build_preset_dir), ignore_errors=True)

    user_vars_cmake_module = ladybird_source_dir.joinpath("Meta", "CMake", "vcpkg", "user-variables.cmake")
    user_vars_cmake_module.unlink(missing_ok=True)


def addr2line_main(build_dir, target: str, program: str, addresses: list[str]):
    if not shutil.which(program):
        print(f"Please install {program}!", file=sys.stderr)
        sys.exit(1)

    binary_file_path = None
    for root, _, files in os.walk(build_dir):
        if target in files:
            candidate = Path(root) / target
            if os.access(candidate, os.X_OK):
                binary_file_path = str(candidate)

    if not binary_file_path:
        print(f'Unable to find binary target "{target}" in build directory "{build_dir}"', file=sys.stderr)
        sys.exit(1)

    addr2line_args = [
        program,
        "-o" if program == "atos" else "-e",
        binary_file_path,
    ]
    addr2line_args.extend(addresses)

    run_command(addr2line_args, exit_on_failure=True)


if __name__ == "__main__":
    main()