# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.

from __future__ import absolute_import, print_function, unicode_literals

import buildconfig
import errno
import mozfile
import os
import platform
import shutil
import subprocess

from mozbuild.util import ensureParentDir

is_linux = platform.system() == "Linux"


def mkdir(dir):
    if not os.path.isdir(dir):
        try:
            os.makedirs(dir)
        except OSError as e:
            if e.errno != errno.EEXIST:
                raise


def chmod(dir):
    "Set permissions of DMG contents correctly"
    subprocess.check_call(["chmod", "-R", "a+rX,a-st,u+w,go-w", dir])


def rsync(source, dest):
    "rsync the contents of directory source into directory dest"
    # Ensure a trailing slash on directories so rsync copies the *contents* of source.
    if not source.endswith("/") and os.path.isdir(source):
        source += "/"
    subprocess.check_call(["rsync", "-a", "--copy-unsafe-links", source, dest])


def set_folder_icon(dir, tmpdir):
    "Set HFS attributes of dir to use a custom icon"
    if not is_linux:
        subprocess.check_call(["SetFile", "-a", "C", dir])
    else:
        hfs = os.path.join(tmpdir, "staged.hfs")
        subprocess.check_call([buildconfig.substs["HFS_TOOL"], hfs, "attr", "/", "C"])


def generate_hfs_file(stagedir, tmpdir, volume_name):
    """
    When cross compiling, we zero fill an hfs file, that we will turn into
    a DMG. To do so we test the size of the staged dir, and add some slight
    padding to that.
    """
    if is_linux:
        hfs = os.path.join(tmpdir, "staged.hfs")
        output = subprocess.check_output(["du", "-s", stagedir])
        size = int(output.split()[0]) / 1000  # Get in MB
        size = int(size * 1.02)  # Bump the used size slightly larger.
        # Setup a proper file sized out with zero's
        subprocess.check_call(
            [
                "dd",
                "if=/dev/zero",
                "of={}".format(hfs),
                "bs=1M",
                "count={}".format(size),
            ]
        )
        subprocess.check_call([buildconfig.substs["MKFSHFS"], "-v", volume_name, hfs])


def create_app_symlink(stagedir, tmpdir):
    """
    Make a symlink to /Applications. The symlink name is a space
    so we don't have to localize it. The Applications folder icon
    will be shown in Finder, which should be clear enough for users.
    """
    if is_linux:
        hfs = os.path.join(tmpdir, "staged.hfs")
        subprocess.check_call(
            [buildconfig.substs["HFS_TOOL"], hfs, "symlink", "/ ", "/Applications"]
        )
    else:
        os.symlink("/Applications", os.path.join(stagedir, " "))


def create_dmg_from_staged(stagedir, output_dmg, tmpdir, volume_name):
    "Given a prepared directory stagedir, produce a DMG at output_dmg."
    if not is_linux:
        # Running on OS X
        hybrid = os.path.join(tmpdir, "hybrid.dmg")
        subprocess.check_call(
            [
                "hdiutil",
                "makehybrid",
                "-hfs",
                "-hfs-volume-name",
                volume_name,
                "-hfs-openfolder",
                stagedir,
                "-ov",
                stagedir,
                "-o",
                hybrid,
            ]
        )
        subprocess.check_call(
            [
                "hdiutil",
                "convert",
                "-format",
                "UDBZ",
                "-imagekey",
                "bzip2-level=9",
                "-ov",
                hybrid,
                "-o",
                output_dmg,
            ]
        )
    else:
        # The dmg tool doesn't create the destination directories, and silently
        # returns success if the parent directory doesn't exist.
        ensureParentDir(output_dmg)

        hfs = os.path.join(tmpdir, "staged.hfs")
        subprocess.check_call([buildconfig.substs["HFS_TOOL"], hfs, "addall", stagedir])
        subprocess.check_call(
            [buildconfig.substs["DMG_TOOL"], "build", hfs, output_dmg],
            # dmg is seriously chatty
            stdout=open(os.devnull, "wb"),
        )


def check_tools(*tools):
    """
    Check that each tool named in tools exists in SUBSTS and is executable.
    """
    for tool in tools:
        path = buildconfig.substs[tool]
        if not path:
            raise Exception('Required tool "%s" not found' % tool)
        if not os.path.isfile(path):
            raise Exception('Required tool "%s" not found at path "%s"' % (tool, path))
        if not os.access(path, os.X_OK):
            raise Exception(
                'Required tool "%s" at path "%s" is not executable' % (tool, path)
            )


def create_dmg(source_directory, output_dmg, volume_name, extra_files):
    """
    Create a DMG disk image at the path output_dmg from source_directory.

    Use volume_name as the disk image volume name, and
    use extra_files as a list of tuples of (filename, relative path) to copy
    into the disk image.
    """
    if platform.system() not in ("Darwin", "Linux"):
        raise Exception("Don't know how to build a DMG on '%s'" % platform.system())

    if is_linux:
        check_tools("DMG_TOOL", "MKFSHFS", "HFS_TOOL")
    with mozfile.TemporaryDirectory() as tmpdir:
        stagedir = os.path.join(tmpdir, "stage")
        os.mkdir(stagedir)
        # Copy the app bundle over using rsync
        rsync(source_directory, stagedir)
        # Copy extra files
        for source, target in extra_files:
            full_target = os.path.join(stagedir, target)
            mkdir(os.path.dirname(full_target))
            shutil.copyfile(source, full_target)
        generate_hfs_file(stagedir, tmpdir, volume_name)
        create_app_symlink(stagedir, tmpdir)
        # Set the folder attributes to use a custom icon
        set_folder_icon(stagedir, tmpdir)
        chmod(stagedir)
        create_dmg_from_staged(stagedir, output_dmg, tmpdir, volume_name)


def extract_dmg_contents(dmgfile, destdir):
    import buildconfig

    if is_linux:
        with mozfile.TemporaryDirectory() as tmpdir:
            hfs_file = os.path.join(tmpdir, "firefox.hfs")
            subprocess.check_call(
                [buildconfig.substs["DMG_TOOL"], "extract", dmgfile, hfs_file],
                # dmg is seriously chatty
                stdout=open(os.devnull, "wb"),
            )
            subprocess.check_call(
                [buildconfig.substs["HFS_TOOL"], hfs_file, "extractall", "/", destdir]
            )
    else:
        unpack_diskimage = os.path.join(
            buildconfig.topsrcdir, "build", "package", "mac_osx", "unpack-diskimage"
        )
        unpack_mountpoint = os.path.join(
            "/tmp", "{}-unpack".format(buildconfig.substs["MOZ_APP_NAME"])
        )
        subprocess.check_call([unpack_diskimage, dmgfile, unpack_mountpoint, destdir])


def extract_dmg(dmgfile, output, dsstore=None, icon=None, background=None):
    if platform.system() not in ("Darwin", "Linux"):
        raise Exception("Don't know how to extract a DMG on '%s'" % platform.system())

    if is_linux:
        check_tools("DMG_TOOL", "MKFSHFS", "HFS_TOOL")

    with mozfile.TemporaryDirectory() as tmpdir:
        extract_dmg_contents(dmgfile, tmpdir)
        if os.path.islink(os.path.join(tmpdir, " ")):
            # Rsync will fail on the presence of this symlink
            os.remove(os.path.join(tmpdir, " "))
        rsync(tmpdir, output)

        if dsstore:
            mkdir(os.path.dirname(dsstore))
            rsync(os.path.join(tmpdir, ".DS_Store"), dsstore)
        if background:
            mkdir(os.path.dirname(background))
            rsync(
                os.path.join(tmpdir, ".background", os.path.basename(background)),
                background,
            )
        if icon:
            mkdir(os.path.dirname(icon))
            rsync(os.path.join(tmpdir, ".VolumeIcon.icns"), icon)