# Copyright 2021 The IREE Authors
#
# Licensed under the Apache License v2.0 with LLVM Exceptions.
# See https://llvm.org/LICENSE.txt for license information.
# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

# Build/install the iree-compiler-backend python package.
# Note that this includes a relatively large build of LLVM (~2400 C++ files)
# and can take a considerable amount of time, especially with defaults.
# To install:
#   pip install .
# To build a wheel:
#   pip wheel .
#
# It is recommended to build with Ninja and ccache. To do so, set environment
# variables by prefixing to above invocations:
#   CMAKE_C_COMPILER_LAUNCHER=ccache CMAKE_CXX_COMPILER_LAUNCHER=ccache
#
# On CIs, it is often advantageous to re-use/control the CMake build directory.
# This can be set with the IREE_COMPILER_API_CMAKE_BUILD_DIR env var.
#
# Select CMake options are available from environment variables:
#   IREE_TARGET_BACKEND_CUDA
#   IREE_ENABLE_CPUINFO

from gettext import install
import json
from multiprocessing.spawn import prepare
import os
import platform
import re
import shutil
import subprocess
import sys
import sysconfig

from distutils.command.build import build as _build
from setuptools import find_namespace_packages, setup, Extension
from setuptools.command.build_ext import build_ext as _build_ext
from setuptools.command.build_py import build_py as _build_py


def check_pip_version():
    from packaging import version

    # Pip versions < 22.0.3 default to out of tree builds, which is quite
    # incompatible with what we do (and has other issues). Pip >= 22.0.4
    # removed this option entirely and are only in-tree builds. Since the
    # old behavior can silently produce unworking installations, we aggressively
    # suppress it.
    try:
        import pip
    except ModuleNotFoundError:
        # If pip not installed, we are obviously not trying to package via pip.
        pass
    else:
        if version.parse(pip.__version__) < version.parse("21.3"):
            print("ERROR: pip version >= 21.3 required")
            print("Upgrade: pip install pip --upgrade")
            sys.exit(2)


check_pip_version()

# This file can be run directly from the source tree or it can be CMake
# configured so it can run from the build tree with an already existing
# build tree. We detect the difference based on whether the following
# are expanded by CMake.
CONFIGURED_SOURCE_DIR = "@IREE_SOURCE_DIR@"
CONFIGURED_BINARY_DIR = "@IREE_BINARY_DIR@"

IREE_SOURCE_DIR = None
IREE_BINARY_DIR = None

# We must do the intermediate installation to a fixed location that agrees
# between what we pass to setup() and cmake. So hard-code it here.
# Note that setup() needs a relative path (to the setup.py file).
SETUPPY_DIR = os.path.realpath(os.path.dirname(__file__))
CMAKE_INSTALL_DIR_REL = os.path.join("build", "cmake_install")
CMAKE_INSTALL_DIR_ABS = os.path.join(SETUPPY_DIR, CMAKE_INSTALL_DIR_REL)

IS_CONFIGURED = CONFIGURED_SOURCE_DIR[0] != "@"
if IS_CONFIGURED:
    IREE_SOURCE_DIR = CONFIGURED_SOURCE_DIR
    IREE_BINARY_DIR = CONFIGURED_BINARY_DIR
    print(
        f"Running setup.py from build tree: "
        f"SOURCE_DIR = {IREE_SOURCE_DIR} "
        f"BINARY_DIR = {IREE_BINARY_DIR}",
        file=sys.stderr,
    )
else:
    IREE_SOURCE_DIR = os.path.join(SETUPPY_DIR, "..")
    IREE_BINARY_DIR = os.getenv("IREE_COMPILER_API_CMAKE_BUILD_DIR")
    if not IREE_BINARY_DIR:
        # Note that setuptools always builds into a "build" directory that
        # is a sibling of setup.py, so we just colonize a sub-directory of that
        # by default.
        IREE_BINARY_DIR = os.path.join(SETUPPY_DIR, "build", "cmake_build")
    print(
        f"Running setup.py from source tree: "
        f"SOURCE_DIR = {IREE_SOURCE_DIR} "
        f"BINARY_DIR = {IREE_BINARY_DIR}",
        file=sys.stderr,
    )

# Setup and get version information.
VERSION_INFO_FILE = os.path.join(IREE_SOURCE_DIR, "version_info.json")


def load_version_info():
    with open(VERSION_INFO_FILE, "rt") as f:
        return json.load(f)


def find_git_versions():
    revisions = {}
    try:
        revisions["IREE"] = (
            subprocess.check_output(["git", "rev-parse", "HEAD"], cwd=IREE_SOURCE_DIR)
            .decode("utf-8")
            .strip()
        )
    except subprocess.SubprocessError as e:
        print(f"ERROR: Could not get IREE revision: {e}", file=sys.stderr)
    return revisions


def find_git_submodule_revision(submodule_path):
    try:
        data = (
            subprocess.check_output(
                ["git", "ls-tree", "HEAD", submodule_path], cwd=IREE_SOURCE_DIR
            )
            .decode("utf-8")
            .strip()
        )
        columns = re.split("\\s+", data)
        return columns[2]
    except Exception as e:
        print(
            f"ERROR: Could not get submodule revision for {submodule_path}" f" ({e})",
            file=sys.stderr,
        )
        return ""


try:
    version_info = load_version_info()
except FileNotFoundError:
    print("version_info.json not found. Using defaults", file=sys.stderr)
    version_info = {}
git_versions = find_git_versions()

PACKAGE_SUFFIX = version_info.get("package-suffix") or ""
PACKAGE_VERSION = version_info.get("package-version")
if not PACKAGE_VERSION:
    PACKAGE_VERSION = f"0.dev0+{git_versions.get('IREE') or '0'}"


def get_cmake_version_info_args():
    version_info_args = [
        f"-DIREE_RELEASE_VERSION:STRING={PACKAGE_VERSION}",
        f"-DIREE_RELEASE_REVISION:STRING={git_versions.get('IREE') or '0'}",
    ]
    if version_info:
        version_info_args.append("-DIREE_EMBEDDED_RELEASE_INFO=ON")
    return version_info_args


def maybe_nuke_cmake_cache():
    # From run to run under pip, we can end up with different paths to ninja,
    # which isn't great and will confuse cmake. Detect if the location of
    # ninja changes and force a cache flush.
    ninja_path = ""
    try:
        import ninja
    except ModuleNotFoundError:
        pass
    else:
        ninja_path = ninja.__file__
    expected_stamp_contents = f"{sys.executable}\n{ninja_path}"

    # In order to speed things up on CI and not rebuild everything, we nuke
    # the CMakeCache.txt file if the path to the Python interpreter changed.
    # Ideally, CMake would let us reconfigure this dynamically... but it does
    # not (and gets very confused).
    # We only do this because the compiler is so expensive to build and very
    # little of it depends on the Python version. This is a hack.
    PYTHON_STAMP_FILE = os.path.join(IREE_BINARY_DIR, "python_stamp.txt")
    if os.path.exists(PYTHON_STAMP_FILE):
        with open(PYTHON_STAMP_FILE, "rt") as f:
            actual_stamp_contents = f.read()
            if actual_stamp_contents == expected_stamp_contents:
                # All good.
                return

    # Mismatch or not found. Clean it.
    cmake_cache_file = os.path.join(IREE_BINARY_DIR, "CMakeCache.txt")
    if os.path.exists(cmake_cache_file):
        print("Removing CMakeCache.txt because Python version changed", file=sys.stderr)
        os.remove(cmake_cache_file)

    # Also clean the install directory. This avoids version specific pileups
    # of binaries that can occur with repeated builds against different
    # Python versions.
    if os.path.exists(CMAKE_INSTALL_DIR_ABS):
        print(
            f"Removing CMake install dir because Python version changed: "
            f"{CMAKE_INSTALL_DIR_ABS}",
            file=sys.stderr,
        )
        shutil.rmtree(CMAKE_INSTALL_DIR_ABS)

    # And write.
    with open(PYTHON_STAMP_FILE, "wt") as f:
        f.write(expected_stamp_contents)


def get_env_cmake_option(name: str, default_value: bool = False) -> str:
    svalue = os.getenv(name)
    if not svalue:
        svalue = "ON" if default_value else "OFF"
    return f"-D{name}={svalue}"


def add_env_cmake_setting(args, env_name: str, cmake_name=None) -> str:
    svalue = os.getenv(env_name)
    if svalue is not None:
        if not cmake_name:
            cmake_name = env_name
        args.append(f"-D{cmake_name}={svalue}")


def prepare_installation():
    version_py_content = generate_version_py()
    print(f"Generating version.py:\n{version_py_content}", file=sys.stderr)

    cfg = os.getenv("IREE_CMAKE_BUILD_TYPE", "Release")
    strip_install = cfg == "Release"

    if not IS_CONFIGURED:
        # Build from source tree.
        subprocess.check_call(["cmake", "--version"])
        os.makedirs(IREE_BINARY_DIR, exist_ok=True)
        maybe_nuke_cmake_cache()
        print(f"CMake build dir: {IREE_BINARY_DIR}", file=sys.stderr)
        print(f"CMake install dir: {CMAKE_INSTALL_DIR_ABS}", file=sys.stderr)
        cmake_args = [
            "-GNinja",
            "--log-level=VERBOSE",
            "-DIREE_BUILD_PYTHON_BINDINGS=ON",
            # Disable .so.0 style symlinking. Python wheels don't preserve links,
            # so this ~doubles the binary size if not disabled (yikes!).
            "-DCMAKE_PLATFORM_NO_VERSIONED_SONAME=ON",
            "-DPython3_EXECUTABLE={}".format(sys.executable),
            "-DCMAKE_BUILD_TYPE={}".format(cfg),
            get_env_cmake_option("IREE_TARGET_BACKEND_CUDA"),
            # TODO(scotttodd): include IREE_TARGET_BACKEND_WEBGPU here (and in env)
            get_env_cmake_option("IREE_ENABLE_CPUINFO", "ON"),
        ]
        cmake_args.extend(get_cmake_version_info_args())

        # These usually flow through the environment, but we add them explicitly
        # so that they show clearly in logs (getting them wrong can have bad
        # outcomes).
        add_env_cmake_setting(cmake_args, "CMAKE_OSX_ARCHITECTURES")
        add_env_cmake_setting(
            cmake_args, "MACOSX_DEPLOYMENT_TARGET", "CMAKE_OSX_DEPLOYMENT_TARGET"
        )

        # Only do a from-scratch configure if not already configured.
        cmake_cache_file = os.path.join(IREE_BINARY_DIR, "CMakeCache.txt")
        if not os.path.exists(cmake_cache_file):
            print(f"Configuring with: {cmake_args}", file=sys.stderr)
            subprocess.check_call(
                ["cmake", IREE_SOURCE_DIR] + cmake_args, cwd=IREE_BINARY_DIR
            )
        else:
            print(f"Not re-configuring (already configured)", file=sys.stderr)

        # Build.
        subprocess.check_call(["cmake", "--build", "."], cwd=IREE_BINARY_DIR)
        print("Build complete.", file=sys.stderr)

    # Perform installation on the entire compiler/ tree as this is guaranteed
    # to have all of our installation targets.
    install_subdirectory = os.path.join(IREE_BINARY_DIR)
    install_args = [
        f"-DCMAKE_INSTALL_PREFIX={CMAKE_INSTALL_DIR_ABS}",
        "-P",
        os.path.join(install_subdirectory, "cmake_install.cmake"),
    ]
    if strip_install:
        install_args.append("-DCMAKE_INSTALL_DO_STRIP=ON")
    print(f"Installing with: {install_args}", file=sys.stderr)
    subprocess.check_call(["cmake"] + install_args, cwd=install_subdirectory)

    # Write version.py directly into install dir.
    version_py_file = os.path.join(
        CMAKE_INSTALL_DIR_ABS,
        "python_packages",
        "iree_compiler",
        "iree",
        "compiler",
        "version.py",
    )
    os.makedirs(os.path.dirname(version_py_file), exist_ok=True)
    with open(version_py_file, "wt") as f:
        f.write(version_py_content)

    print(f"Installation prepared: {CMAKE_INSTALL_DIR_ABS}", file=sys.stderr)


class CMakeBuildPy(_build_py):
    def run(self):
        # It is critical that the target directory contain all built extensions,
        # or else setuptools will helpfully compile an empty binary for us
        # (this is the **worst** possible thing it could do). We just copy
        # everything. What's another hundred megs between friends?
        target_dir = os.path.abspath(self.build_lib)
        print(f"Building in target dir: {target_dir}", file=sys.stderr)
        os.makedirs(target_dir, exist_ok=True)
        print("Copying install to target.", file=sys.stderr)
        if os.path.exists(target_dir):
            shutil.rmtree(target_dir)
        shutil.copytree(
            os.path.join(CMAKE_INSTALL_DIR_ABS, "python_packages", "iree_compiler"),
            target_dir,
            symlinks=False,
        )
        print("Target populated.", file=sys.stderr)


class CustomBuild(_build):
    def run(self):
        self.run_command("build_py")
        self.run_command("build_ext")
        self.run_command("build_scripts")


class CMakeExtension(Extension):
    def __init__(self, name, sourcedir=""):
        Extension.__init__(self, name, sources=[])
        self.sourcedir = os.path.abspath(sourcedir)


class NoopBuildExtension(_build_ext):
    def __init__(self, *args, **kwargs):
        assert False

    def build_extension(self, ext):
        pass


def generate_version_py():
    return f"""# Auto-generated version info.
PACKAGE_SUFFIX = "{PACKAGE_SUFFIX}"
VERSION = "{PACKAGE_VERSION}"
REVISIONS = {json.dumps(git_versions)}
"""


def find_git_versions():
    revisions = {}
    try:
        revisions["IREE"] = (
            subprocess.check_output(["git", "rev-parse", "HEAD"], cwd=IREE_SOURCE_DIR)
            .decode("utf-8")
            .strip()
        )
    except subprocess.SubprocessError as e:
        print(f"ERROR: Could not get IREE revision: {e}", file=sys.stderr)
    revisions["LLVM_PROJECT"] = find_git_submodule_revision("third_party/llvm-project")
    revisions["STABLEHLO"] = find_git_submodule_revision("third_party/stablehlo")
    return revisions


def find_git_submodule_revision(submodule_path):
    try:
        data = (
            subprocess.check_output(
                ["git", "ls-tree", "HEAD", submodule_path], cwd=IREE_SOURCE_DIR
            )
            .decode("utf-8")
            .strip()
        )
        columns = re.split("\\s+", data)
        return columns[2]
    except Exception as e:
        print(
            f"ERROR: Could not get submodule revision for {submodule_path}" f" ({e})",
            file=sys.stderr,
        )
        return ""


prepare_installation()

packages = find_namespace_packages(
    where=os.path.join(CMAKE_INSTALL_DIR_ABS, "python_packages", "iree_compiler"),
    include=[
        "iree.compiler",
        "iree.compiler.*",
    ],
)
print(f"Found compiler packages: {packages}")

custom_package_suffix = os.getenv("IREE_COMPILER_CUSTOM_PACKAGE_SUFFIX", "")
custom_package_prefix = os.getenv("IREE_COMPILER_CUSTOM_PACKAGE_PREFIX", "")

setup(
    name=f"{custom_package_prefix}iree-compiler{custom_package_suffix}{PACKAGE_SUFFIX}",
    version=f"{PACKAGE_VERSION}",
    author="IREE Authors",
    author_email="iree-discuss@googlegroups.com",
    description="IREE Compiler API",
    long_description="",
    license="Apache-2.0",
    classifiers=[
        "Development Status :: 3 - Alpha",
        "License :: OSI Approved :: Apache Software License",
        "Programming Language :: Python :: 3",
        "Programming Language :: Python :: 3.8",
        "Programming Language :: Python :: 3.9",
        "Programming Language :: Python :: 3.10",
        "Programming Language :: Python :: 3.11",
    ],
    ext_modules=[
        CMakeExtension("iree.compiler._mlir_libs._mlir"),
        CMakeExtension("iree.compiler._mlir_libs._ireeDialects"),
        # TODO: MHLO has been broken for a while so disabling. If re-enabling,
        # it also needs to be enabled on the build side.
        # CMakeExtension("iree.compiler._mlir_libs._mlirHlo"),
        CMakeExtension("iree.compiler._mlir_libs._mlirLinalgPasses"),
        CMakeExtension("iree.compiler._mlir_libs._site_initialize_0"),
    ],
    cmdclass={
        "build": CustomBuild,
        "built_ext": NoopBuildExtension,
        "build_py": CMakeBuildPy,
    },
    zip_safe=False,
    package_dir={
        # Note: Must be relative path, so we line this up with the absolute
        # path built above. Note that this must exist prior to the call.
        "": f"{CMAKE_INSTALL_DIR_REL}/python_packages/iree_compiler",
    },
    packages=packages,
    entry_points={
        "console_scripts": [
            "iree-compile = iree.compiler.tools.scripts.ireec.__main__:main",
            # TODO: We have renamed to iree-compile on 2022-03-18. Remove
            # this alias once no longer needed.
            "ireec = iree.compiler.tools.scripts.ireec.__main__:main",
        ],
    },
    install_requires=[
        "numpy",
        "PyYAML",
    ],
)