#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# Copyright 2010 The ChromiumOS Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Script to build the ChromeOS toolchain.

This script sets up the toolchain if you give it the gcctools directory.
"""


__author__ = "asharif@google.com (Ahmad Sharif)"

import argparse
import getpass
import os
import sys
import tempfile

from cros_utils import command_executer
from cros_utils import constants
from cros_utils import misc
import tc_enter_chroot


class ToolchainPart(object):
    """Class to hold the toolchain pieces."""

    def __init__(
        self,
        name,
        source_path,
        chromeos_root,
        board,
        incremental,
        build_env,
        gcc_enable_ccache=False,
    ):
        self._name = name
        self._source_path = misc.CanonicalizePath(source_path)
        self._chromeos_root = chromeos_root
        self._board = board
        self._ctarget = misc.GetCtargetFromBoard(
            self._board, self._chromeos_root
        )
        self._gcc_libs_dest = misc.GetGccLibsDestForBoard(
            self._board, self._chromeos_root
        )
        self.tag = "%s-%s" % (name, self._ctarget)
        self._ce = command_executer.GetCommandExecuter()
        self._mask_file = os.path.join(
            self._chromeos_root,
            "chroot",
            "etc/portage/package.mask/cross-%s" % self._ctarget,
        )
        self._new_mask_file = None

        self._chroot_source_path = os.path.join(
            constants.MOUNTED_TOOLCHAIN_ROOT, self._name
        ).lstrip("/")
        self._incremental = incremental
        self._build_env = build_env
        self._gcc_enable_ccache = gcc_enable_ccache

    def RunSetupBoardIfNecessary(self):
        cross_symlink = os.path.join(
            self._chromeos_root,
            "chroot",
            "usr/local/bin/emerge-%s" % self._board,
        )
        if not os.path.exists(cross_symlink):
            command = "setup_board --board=%s" % self._board
            self._ce.ChrootRunCommand(self._chromeos_root, command)

    def Build(self):
        rv = 1
        try:
            self.UninstallTool()
            self.MoveMaskFile()
            self.MountSources(False)
            self.RemoveCompiledFile()
            rv = self.BuildTool()
        finally:
            self.UnMoveMaskFile()
        return rv

    def RemoveCompiledFile(self):
        compiled_file = os.path.join(
            self._chromeos_root,
            "chroot",
            "var/tmp/portage/cross-%s" % self._ctarget,
            "%s-9999" % self._name,
            ".compiled",
        )
        command = "rm -f %s" % compiled_file
        self._ce.RunCommand(command)

    def MountSources(self, unmount_source):
        mount_points = []
        mounted_source_path = os.path.join(
            self._chromeos_root, "chroot", self._chroot_source_path
        )
        src_mp = tc_enter_chroot.MountPoint(
            self._source_path, mounted_source_path, getpass.getuser(), "ro"
        )
        mount_points.append(src_mp)

        build_suffix = "build-%s" % self._ctarget
        build_dir = "%s-%s" % (self._source_path, build_suffix)

        if not self._incremental and os.path.exists(build_dir):
            command = "rm -rf %s/*" % build_dir
            self._ce.RunCommand(command)

        # Create a -build directory for the objects.
        command = "mkdir -p %s" % build_dir
        self._ce.RunCommand(command)

        mounted_build_dir = os.path.join(
            self._chromeos_root,
            "chroot",
            "%s-%s" % (self._chroot_source_path, build_suffix),
        )
        build_mp = tc_enter_chroot.MountPoint(
            build_dir, mounted_build_dir, getpass.getuser()
        )
        mount_points.append(build_mp)

        if unmount_source:
            unmount_statuses = [mp.UnMount() == 0 for mp in mount_points]
            assert all(unmount_statuses), "Could not unmount all mount points!"
        else:
            mount_statuses = [mp.DoMount() == 0 for mp in mount_points]

            if not all(mount_statuses):
                mounted = [
                    mp
                    for mp, status in zip(mount_points, mount_statuses)
                    if status
                ]
                unmount_statuses = [mp.UnMount() == 0 for mp in mounted]
                assert all(
                    unmount_statuses
                ), "Could not unmount all mount points!"

    def UninstallTool(self):
        command = "sudo CLEAN_DELAY=0 emerge -C cross-%s/%s" % (
            self._ctarget,
            self._name,
        )
        self._ce.ChrootRunCommand(self._chromeos_root, command)

    def BuildTool(self):
        env = self._build_env
        # FEATURES=buildpkg adds minutes of time so we disable it.
        # TODO(shenhan): keep '-sandbox' for a while for compatibility, then remove
        # it after a while.
        features = (
            "nostrip userpriv userfetch -usersandbox -sandbox noclean "
            "-buildpkg"
        )
        env["FEATURES"] = features

        if self._incremental:
            env["FEATURES"] += " keepwork"

        if "USE" in env:
            env["USE"] += " multislot mounted_%s" % self._name
        else:
            env["USE"] = "multislot mounted_%s" % self._name

        # Disable ccache in our compilers. cache may be problematic for us.
        # It ignores compiler environments settings and it is not clear if
        # the cache hit algorithm verifies all the compiler binaries or
        # just the driver.
        if self._name == "gcc" and not self._gcc_enable_ccache:
            env["USE"] += " -wrapper_ccache"

        env["%s_SOURCE_PATH" % self._name.upper()] = os.path.join(
            "/", self._chroot_source_path
        )
        env["ACCEPT_KEYWORDS"] = "~*"
        env_string = " ".join(['%s="%s"' % var for var in env.items()])
        command = "emerge =cross-%s/%s-9999" % (self._ctarget, self._name)
        full_command = "sudo %s %s" % (env_string, command)
        rv = self._ce.ChrootRunCommand(self._chromeos_root, full_command)
        if rv != 0:
            return rv
        if self._name == "gcc":
            command = "sudo cp -r /usr/lib/gcc/%s %s" % (
                self._ctarget,
                self._gcc_libs_dest,
            )
            rv = self._ce.ChrootRunCommand(self._chromeos_root, command)
        return rv

    def MoveMaskFile(self):
        self._new_mask_file = None
        if os.path.isfile(self._mask_file):
            self._new_mask_file = tempfile.mktemp()
            command = "sudo mv %s %s" % (self._mask_file, self._new_mask_file)
            self._ce.RunCommand(command)

    def UnMoveMaskFile(self):
        if self._new_mask_file:
            command = "sudo mv %s %s" % (self._new_mask_file, self._mask_file)
            self._ce.RunCommand(command)


def Main(argv):
    """The main function."""
    # Common initializations
    parser = argparse.ArgumentParser()
    parser.add_argument(
        "-c",
        "--chromeos_root",
        dest="chromeos_root",
        default="../../",
        help=("ChromeOS root checkout directory" " uses ../.. if none given."),
    )
    parser.add_argument(
        "-g",
        "--gcc_dir",
        dest="gcc_dir",
        help="The directory where gcc resides.",
    )
    parser.add_argument(
        "--binutils_dir",
        dest="binutils_dir",
        help="The directory where binutils resides.",
    )
    parser.add_argument(
        "-x",
        "--gdb_dir",
        dest="gdb_dir",
        help="The directory where gdb resides.",
    )
    parser.add_argument(
        "-b",
        "--board",
        dest="board",
        default="x86-alex",
        help="The target board.",
    )
    parser.add_argument(
        "-n",
        "--noincremental",
        dest="noincremental",
        default=False,
        action="store_true",
        help="Use FEATURES=keepwork to do incremental builds.",
    )
    parser.add_argument(
        "--cflags",
        dest="cflags",
        default="",
        help="Build a compiler with specified CFLAGS",
    )
    parser.add_argument(
        "--cxxflags",
        dest="cxxflags",
        default="",
        help="Build a compiler with specified CXXFLAGS",
    )
    parser.add_argument(
        "--cflags_for_target",
        dest="cflags_for_target",
        default="",
        help="Build the target libraries with specified flags",
    )
    parser.add_argument(
        "--cxxflags_for_target",
        dest="cxxflags_for_target",
        default="",
        help="Build the target libraries with specified flags",
    )
    parser.add_argument(
        "--ldflags",
        dest="ldflags",
        default="",
        help="Build a compiler with specified LDFLAGS",
    )
    parser.add_argument(
        "-d",
        "--debug",
        dest="debug",
        default=False,
        action="store_true",
        help="Build a compiler with -g3 -O0 appended to both"
        " CFLAGS and CXXFLAGS.",
    )
    parser.add_argument(
        "-m",
        "--mount_only",
        dest="mount_only",
        default=False,
        action="store_true",
        help="Just mount the tool directories.",
    )
    parser.add_argument(
        "-u",
        "--unmount_only",
        dest="unmount_only",
        default=False,
        action="store_true",
        help="Just unmount the tool directories.",
    )
    parser.add_argument(
        "--extra_use_flags",
        dest="extra_use_flags",
        default="",
        help="Extra flag for USE, to be passed to the ebuild. "
        "('multislot' and 'mounted_<tool>' are always passed.)",
    )
    parser.add_argument(
        "--gcc_enable_ccache",
        dest="gcc_enable_ccache",
        default=False,
        action="store_true",
        help="Enable ccache for the gcc invocations",
    )

    options = parser.parse_args(argv)

    chromeos_root = misc.CanonicalizePath(options.chromeos_root)
    if options.gcc_dir:
        gcc_dir = misc.CanonicalizePath(options.gcc_dir)
        assert gcc_dir and os.path.isdir(gcc_dir), "gcc_dir does not exist!"
    if options.binutils_dir:
        binutils_dir = misc.CanonicalizePath(options.binutils_dir)
        assert os.path.isdir(binutils_dir), "binutils_dir does not exist!"
    if options.gdb_dir:
        gdb_dir = misc.CanonicalizePath(options.gdb_dir)
        assert os.path.isdir(gdb_dir), "gdb_dir does not exist!"
    if options.unmount_only:
        options.mount_only = False
    elif options.mount_only:
        options.unmount_only = False
    build_env = {}
    if options.cflags:
        build_env["CFLAGS"] = "`portageq envvar CFLAGS` " + options.cflags
    if options.cxxflags:
        build_env["CXXFLAGS"] = "`portageq envvar CXXFLAGS` " + options.cxxflags
    if options.cflags_for_target:
        build_env["CFLAGS_FOR_TARGET"] = options.cflags_for_target
    if options.cxxflags_for_target:
        build_env["CXXFLAGS_FOR_TARGET"] = options.cxxflags_for_target
    if options.ldflags:
        build_env["LDFLAGS"] = options.ldflags
    if options.debug:
        debug_flags = "-g3 -O0"
        if "CFLAGS" in build_env:
            build_env["CFLAGS"] += " %s" % (debug_flags)
        else:
            build_env["CFLAGS"] = debug_flags
        if "CXXFLAGS" in build_env:
            build_env["CXXFLAGS"] += " %s" % (debug_flags)
        else:
            build_env["CXXFLAGS"] = debug_flags
    if options.extra_use_flags:
        build_env["USE"] = options.extra_use_flags

    # Create toolchain parts
    toolchain_parts = {}
    for board in options.board.split(","):
        if options.gcc_dir:
            tp = ToolchainPart(
                "gcc",
                gcc_dir,
                chromeos_root,
                board,
                not options.noincremental,
                build_env,
                options.gcc_enable_ccache,
            )
            toolchain_parts[tp.tag] = tp
            tp.RunSetupBoardIfNecessary()
        if options.binutils_dir:
            tp = ToolchainPart(
                "binutils",
                binutils_dir,
                chromeos_root,
                board,
                not options.noincremental,
                build_env,
            )
            toolchain_parts[tp.tag] = tp
            tp.RunSetupBoardIfNecessary()
        if options.gdb_dir:
            tp = ToolchainPart(
                "gdb",
                gdb_dir,
                chromeos_root,
                board,
                not options.noincremental,
                build_env,
            )
            toolchain_parts[tp.tag] = tp
            tp.RunSetupBoardIfNecessary()

    rv = 0
    try:
        for tag in toolchain_parts:
            tp = toolchain_parts[tag]
            if options.mount_only or options.unmount_only:
                tp.MountSources(options.unmount_only)
            else:
                rv = rv + tp.Build()
    finally:
        print("Exiting...")
    return rv


if __name__ == "__main__":
    retval = Main(sys.argv[1:])
    sys.exit(retval)