// Copyright 2020-2023 The Jujutsu Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use jj_lib::git;
use jj_lib::git::GitSettings;

use crate::cli_util::CommandHelper;
use crate::command_error::CommandError;
use crate::git_util::load_git_import_options;
use crate::git_util::print_git_import_stats;
use crate::ui::Ui;

/// Update repo with changes made in the underlying Git repo
///
/// Commits that are no longer reachable from any branch in the Git repo will be
/// considered abandoned in the Git repo, and will be abandoned in the jj
/// repo to match the Git repo. Set `git.abandon-unreachable-commits` to `false`
/// to disable this behavior.
///
/// If a working-copy commit gets abandoned, it will be given a new, empty
/// commit. This is true in general; it is not specific to this command.
///
/// By default, this command does nothing in colocated workspaces because the
/// import happens automatically. Use `--ignore-working-copy` to forcibly import
/// changes.
#[derive(clap::Args, Clone, Debug)]
pub struct GitImportArgs {}

pub async fn cmd_git_import(
    ui: &mut Ui,
    command: &CommandHelper,
    _args: &GitImportArgs,
) -> Result<(), CommandError> {
    let mut workspace_command = command.workspace_helper(ui).await?;
    if command.is_working_copy_writable() && workspace_command.working_copy_shared_with_git() {
        // Git refs are imported during the snapshot.
        writeln!(ui.status(), "No import needed in colocated workspaces.")?;
        return Ok(());
    }

    let git_settings = GitSettings::from_settings(workspace_command.settings())?;
    let remote_settings = workspace_command.settings().remote_settings()?;
    let import_options = load_git_import_options(ui, &git_settings, &remote_settings)?;
    let mut tx = workspace_command.start_transaction();
    // In non-colocated workspace, Git HEAD will never be moved internally by jj.
    // That's why cmd_git_export() doesn't export the HEAD ref.
    git::import_head(tx.repo_mut()).await?;
    let stats = git::import_refs(tx.repo_mut(), &import_options).await?;
    print_git_import_stats(ui, &tx, &stats)?;
    tx.finish(ui, "import git refs").await?;
    Ok(())
}