#!/usr/bin/env bash
# Shared non-destructive Git update helpers for TA-ProxMenu.

TAPM_GIT_WORKTREE_DIRTY() {
	local repository="$1"

	[[ -n "$(git -C "$repository" status --porcelain --untracked-files=normal 2>/dev/null)" ]]
}

TAPM_GIT_FETCH_BRANCH() {
	local repository="$1"
	local branch="$2"
	local timeout_seconds="${3:-30}"

	timeout "$timeout_seconds" git -C "$repository" fetch --prune origin \
		"+refs/heads/${branch}:refs/remotes/origin/${branch}"
}

TAPM_GIT_RELATION() {
	local repository="$1"
	local local_ref="$2"
	local remote_ref="$3"
	local local_commit
	local remote_commit

	local_commit="$(git -C "$repository" rev-parse --verify "${local_ref}^{commit}" 2>/dev/null)" ||
		return 1
	remote_commit="$(git -C "$repository" rev-parse --verify "${remote_ref}^{commit}" 2>/dev/null)" ||
		return 1

	if [[ "$local_commit" == "$remote_commit" ]]; then
		printf 'current\n'
	elif git -C "$repository" merge-base --is-ancestor "$local_commit" "$remote_commit"; then
		printf 'behind\n'
	elif git -C "$repository" merge-base --is-ancestor "$remote_commit" "$local_commit"; then
		printf 'ahead\n'
	else
		printf 'diverged\n'
	fi
}

TAPM_GIT_BRANCH_STATE() {
	local repository="$1"
	local branch="$2"
	local current_branch

	[[ -d "${repository}/.git" ]] || {
		printf 'unavailable\n'
		return 1
	}

	current_branch="$(git -C "$repository" branch --show-current 2>/dev/null)"
	if [[ -z "$current_branch" ]]; then
		printf 'detached\n'
		return 0
	fi
	if [[ "$current_branch" != "$branch" ]]; then
		printf 'wrong-branch\n'
		return 0
	fi
	if TAPM_GIT_WORKTREE_DIRTY "$repository"; then
		printf 'dirty\n'
		return 0
	fi

	TAPM_GIT_RELATION "$repository" HEAD "refs/remotes/origin/${branch}" || {
		printf 'unavailable\n'
		return 1
	}
}

TAPM_GIT_FAST_FORWARD() {
	local repository="$1"
	local branch="$2"

	git -C "$repository" merge --ff-only "refs/remotes/origin/${branch}"
}