#!/usr/bin/env python3
#
# Copyright (c) 2016-present, Facebook, Inc.
# All rights reserved.
#
# This source code is licensed under the BSD-style license found in the
# LICENSE file in the root directory of this source tree. An additional grant
# of patent rights can be found in the PATENTS file in the same directory.

import errno
import json
import os
import stat
import subprocess
import tempfile
from textwrap import dedent
from typing import Optional, Set

from eden.cli import util

from .lib import edenclient, testcase
from .lib.find_executables import FindExe


# This is the name of the default repository created by EdenRepoTestBase.
repo_name = "main"


@testcase.eden_repo_test
class CloneTest(testcase.EdenRepoTest):
    def populate_repo(self) -> None:
        self.repo.write_file("hello", "hola\n")
        self.repo.commit("Initial commit.")

    def test_clone_to_non_existent_directory(self) -> None:
        tmp = self._new_tmp_dir()
        non_existent_dir = os.path.join(tmp, "foo/bar/baz")

        self.eden.run_cmd("clone", repo_name, non_existent_dir)
        self.assertTrue(
            os.path.isfile(os.path.join(non_existent_dir, "hello")),
            msg="clone should succeed in non-existent directory",
        )

    def test_clone_to_dir_under_symlink(self) -> None:
        tmp = self._new_tmp_dir()
        empty_dir = os.path.join(tmp, "foo/bar")
        os.makedirs(empty_dir)

        symlink_dir = os.path.join(tmp, "food")
        os.symlink(os.path.join(tmp, "foo"), symlink_dir)

        symlinked_target = os.path.join(symlink_dir, "bar")

        self.eden.run_cmd("clone", repo_name, symlinked_target)
        self.assertTrue(
            os.path.isfile(os.path.join(empty_dir, "hello")),
            msg="clone should succeed in empty directory",
        )

        with self.get_thrift_client() as client:
            active_mount_points: Set[Optional[str]] = {
                mount.mountPoint for mount in client.listMounts()
            }
            self.assertIn(
                empty_dir, active_mount_points, msg="mounted using the realpath"
            )

        self.eden.run_cmd("remove", "--yes", symlinked_target)

    def test_clone_to_existing_empty_directory(self) -> None:
        tmp = self._new_tmp_dir()
        empty_dir = os.path.join(tmp, "foo/bar/baz")
        os.makedirs(empty_dir)

        self.eden.run_cmd("clone", repo_name, empty_dir)
        self.assertTrue(
            os.path.isfile(os.path.join(empty_dir, "hello")),
            msg="clone should succeed in empty directory",
        )

    def test_clone_from_repo(self) -> None:
        # Specify the source of the clone as an existing local repo rather than
        # an alias for a config.
        destination_dir = self._new_tmp_dir()
        self.eden.run_cmd("clone", self.repo.path, destination_dir)
        self.assertTrue(
            os.path.isfile(os.path.join(destination_dir, "hello")),
            msg="clone should succeed in empty directory",
        )

    def test_clone_with_arcconfig(self) -> None:
        project_id = "special_project"

        # Remember this state for later
        before_arcconfig = self.repo.get_head_hash()

        # Add an .arcconfig file to the repository
        arcconfig_data = {
            "project_id": project_id,
            "conduit_uri": "https://phabricator.example.com/api/",
            "phutil_libraries": {"foo": "foo/arcanist/"},
        }
        self.repo.write_file(".arcconfig", json.dumps(arcconfig_data) + "\n")
        self.repo.commit("Add .arcconfig")

        # Add a config alias for a repo with some bind mounts.
        edenrc = os.path.join(self.home_dir, ".edenrc")
        with open(edenrc, "w") as f:
            f.write(
                dedent(
                    f"""\
            [repository {project_id}]
            path = {self.repo.get_canonical_root()}
            type = {self.repo.get_type()}

            [bindmounts {project_id}]
            mnt1 = foo/stuff/build_output
            mnt2 = node_modules
            """
                )
            )

        # Clone the repository using its path.
        # We should find the config from the project_id field in
        # the .arcconfig file
        eden_clone = self._new_tmp_dir()
        self.eden.run_cmd("clone", self.repo.path, eden_clone)
        self.assertTrue(
            os.path.isdir(os.path.join(eden_clone, "foo/stuff/build_output")),
            msg="clone should create bind mounts",
        )
        self.assertTrue(
            os.path.isdir(os.path.join(eden_clone, "node_modules")),
            msg="clone should create bind mounts",
        )

        # Let's also check that passing in a rev is effective when
        # the repo is "bare".  We're not actually making it bare here
        # as I'm not sure if we support that concept with git also,
        # so instead I'm moving the repo back to before the arcconfig
        # exists to simulate a similar situation.  The problem that we're
        # testing here is (for mercurial at least), since the default head
        # rev is '.', if the source repo doesn't have an arcconfig we'd
        # never set up the bindmounts, even if the --rev option was passed in.

        # TODO: GitRepository doesn't yet have an update() method, so make
        # this hg specific for now.
        if self.repo.get_type() == "hg":
            head_rev = self.repo.get_head_hash()
            self.repo.update(before_arcconfig)
            alt_eden_clone = self._new_tmp_dir()
            self.eden.run_cmd("clone", "-r", head_rev, self.repo.path, alt_eden_clone)
            self.assertTrue(
                os.path.isdir(os.path.join(alt_eden_clone, "foo/stuff/build_output")),
                msg="clone should create bind mounts",
            )
            self.assertTrue(
                os.path.isdir(os.path.join(alt_eden_clone, "node_modules")),
                msg="clone should create bind mounts",
            )

    def test_clone_from_eden_repo(self) -> None:
        # Add a config alias for a repo with some bind mounts.
        edenrc = os.path.join(self.home_dir, ".edenrc")
        with open(edenrc, "w") as f:
            f.write(
                dedent(
                    f"""\
            [repository {repo_name}]
            path = {self.repo.get_canonical_root()}
            type = {self.repo.get_type()}

            [bindmounts {repo_name}]
            bm1 = tmp/bm1
            bm2 = tmp/bm2
            """
                )
            )

        # Create an Eden mount from the config alias.
        eden_clone1 = self._new_tmp_dir()
        self.eden.run_cmd("clone", repo_name, eden_clone1)
        self.assertTrue(
            os.path.isdir(os.path.join(eden_clone1, "tmp/bm1")),
            msg="clone should create bind mount",
        )

        # Clone the Eden clone! Note it should inherit its config.
        eden_clone2 = self._new_tmp_dir()
        self.eden.run_cmd(
            "clone", "--rev", self.repo.get_head_hash(), eden_clone1, eden_clone2
        )
        self.assertTrue(
            os.path.isdir(os.path.join(eden_clone2, "tmp/bm1")),
            msg="clone should inherit its config from eden_clone1, "
            "which should include the bind mounts.",
        )

    def test_clone_with_valid_revision_cmd_line_arg_works(self) -> None:
        tmp = self._new_tmp_dir()
        target = os.path.join(tmp, "foo/bar/baz")
        self.eden.run_cmd(
            "clone", "--rev", self.repo.get_head_hash(), repo_name, target
        )
        self.assertTrue(
            os.path.isfile(os.path.join(target, "hello")),
            msg="clone should succeed with --snapshop arg.",
        )

    def test_clone_with_short_revision_cmd_line_arg_works(self) -> None:
        tmp = self._new_tmp_dir()
        target = os.path.join(tmp, "foo/bar/baz")
        short = self.repo.get_head_hash()[:6]
        self.eden.run_cmd("clone", "--rev", short, repo_name, target)
        self.assertTrue(
            os.path.isfile(os.path.join(target, "hello")),
            msg="clone should succeed with short --snapshop arg.",
        )

    def test_clone_to_non_empty_directory_fails(self) -> None:
        tmp = self._new_tmp_dir()
        non_empty_dir = os.path.join(tmp, "foo/bar/baz")
        os.makedirs(non_empty_dir)
        with open(os.path.join(non_empty_dir, "example.txt"), "w") as f:
            f.write("I am not empty.\n")

        with self.assertRaises(subprocess.CalledProcessError) as context:
            self.eden.run_cmd("clone", repo_name, non_empty_dir)
        stderr = context.exception.stderr.decode("utf-8")
        self.assertRegex(
            stderr,
            "destination path .* is not empty",
            msg="clone into non-empty dir should fail",
        )

    def test_clone_with_invalid_revision_cmd_line_arg_fails(self) -> None:
        tmp = self._new_tmp_dir()
        empty_dir = os.path.join(tmp, "foo/bar/baz")
        os.makedirs(empty_dir)

        with self.assertRaises(subprocess.CalledProcessError) as context:
            self.eden.run_cmd("clone", repo_name, empty_dir, "--rev", "X")
        stderr = context.exception.stderr.decode("utf-8")
        self.assertIn(
            "unable to find hash for commit 'X': ",
            stderr,
            msg="passing invalid commit on cmd line should fail",
        )

    def test_clone_to_file_fails(self) -> None:
        tmp = self._new_tmp_dir()
        non_empty_dir = os.path.join(tmp, "foo/bar/baz")
        os.makedirs(non_empty_dir)
        file_in_directory = os.path.join(non_empty_dir, "example.txt")
        with open(file_in_directory, "w") as f:
            f.write("I am not empty.\n")

        with self.assertRaises(subprocess.CalledProcessError) as context:
            self.eden.run_cmd("clone", repo_name, file_in_directory)
        stderr = context.exception.stderr.decode("utf-8")
        self.assertEqual(
            stderr, f"error: destination path {file_in_directory} is not a directory\n"
        )

    def test_clone_to_non_existent_directory_that_is_under_a_file_fails(self) -> None:
        tmp = self._new_tmp_dir()
        non_existent_dir = os.path.join(tmp, "foo/bar/baz")
        with open(os.path.join(tmp, "foo"), "w") as f:
            f.write("I am not empty.\n")

        with self.assertRaises(subprocess.CalledProcessError) as context:
            self.eden.run_cmd("clone", repo_name, non_existent_dir)
        stderr = context.exception.stderr.decode("utf-8")
        self.assertEqual(
            stderr, f"error: destination path {non_existent_dir} is not a directory\n"
        )

    def test_post_clone_hook(self) -> None:
        edenrc = os.path.join(self.home_dir, ".edenrc")
        hooks_dir = os.path.join(self.tmp_dir, "the_hooks")
        os.mkdir(hooks_dir)

        with open(edenrc, "w") as f:
            f.write(
                """\
[repository {repo_name}]
path = {repo_path}
type = {repo_type}
hooks = {hooks_dir}
""".format(
                    repo_name=repo_name,
                    repo_path=self.repo.get_canonical_root(),
                    repo_type=self.repo.get_type(),
                    hooks_dir=hooks_dir,
                )
            )

        # Create a post-clone hook that has a visible side-effect every time it
        # is run so we can verify that it is only run once.
        hg_post_clone_hook = os.path.join(hooks_dir, "post-clone")
        scratch_file = os.path.join(self.tmp_dir, "scratch_file")
        with open(scratch_file, "w") as f:
            f.write("ok")
        with open(hg_post_clone_hook, "w") as f:
            f.write(
                """\
#!/bin/bash
CONTENTS=`cat "{scratch_file}"`
echo -n "$1" >> "{scratch_file}"
""".format(
                    scratch_file=scratch_file
                )
            )
        os.chmod(hg_post_clone_hook, stat.S_IRWXU)

        # Verify that the hook gets run as part of `eden clone`.
        self.assertEqual("ok", util.read_all(scratch_file))
        tmp = self._new_tmp_dir()
        self.eden.clone(repo_name, tmp)
        new_contents = "ok" + self.repo.get_type()
        self.assertEqual(new_contents, util.read_all(scratch_file))

        # Restart Eden and verify that post-clone is NOT run again.
        self.eden.shutdown()
        self.eden.start()
        self.assertEqual(new_contents, util.read_all(scratch_file))

    def test_attempt_clone_invalid_repo_name(self) -> None:
        tmp = self._new_tmp_dir()
        repo_name = "repo-name-that-is-not-in-the-config"

        with self.assertRaises(edenclient.EdenCommandError) as context:
            self.eden.run_cmd("clone", repo_name, tmp)
        self.assertEqual(
            context.exception.stderr.decode(),
            f"error: {repo_name!r} does not look like a valid hg or git "
            "repository or a well-known repository name\n",
        )

    def test_clone_should_start_daemon(self) -> None:
        # Shut down Eden.
        self.assertTrue(self.eden.is_healthy())
        self.eden.shutdown()
        self.assertFalse(self.eden.is_healthy())

        # Check `eden list`.
        list_output = self.eden.list_cmd()
        self.assertEqual(
            {self.mount: self.eden.CLIENT_INACTIVE},
            list_output,
            msg="Eden should have one mount.",
        )

        extra_daemon_args = self.eden.get_extra_daemon_args()

        # Verify that clone starts the daemon.
        tmp = self._new_tmp_dir()
        # Set capture_output to False for this clone command: it introduces a
        # hang given how we currently spawn edenfs.  And we will check the
        # daemon's health afterwards.  The hang is caused by Python spawning
        # `sudo edenfs`.  edenfs will itself redirect its own stdout (and the
        # privhelper's stdout) to a log file, but the sudo process sticks
        # around and keeps a reference to the pipe given as stdout, causing
        # _this_ subprocess.run call's communicate() to wait forever.
        # In the long term, the fix is to move daemonization into edenfs
        # itself.  That way it can handle only redirecting its stdout and stderr
        # after startup, when it daemonizes, and to sudo the edenfs process
        # will exit, releasing the pipe file handle.
        self.eden.run_cmd(
            "clone",
            "--daemon-binary",
            FindExe.EDEN_DAEMON,
            self.repo.path,
            tmp,
            "--daemon-args",
            *extra_daemon_args,
            capture_output=False,
        )
        self.assertTrue(self.eden.is_healthy(), msg="clone should start Eden.")
        mount_points = {
            self.mount: self.eden.CLIENT_ACTIVE,
            tmp: self.eden.CLIENT_ACTIVE,
        }
        self.assertEqual(
            mount_points, self.eden.list_cmd(), msg="Eden should have two mounts."
        )
        self.assertEqual("hola\n", util.read_all(os.path.join(tmp, "hello")))

    def _new_tmp_dir(self) -> str:
        return tempfile.mkdtemp(dir=self.tmp_dir)