#!/usr/bin/env bash
#
# checkout files/commit/branches using fzf
#
# @params
# Globals
#   ${mydir}: current directory of the script, used for imports
#   ${action_type}: what type of git commands to use (branch|select|commit|modified)
#   ${selected_branch}: selected_branch to switch
#   ${selected_files}: selected_files to checkout
#   ${selected_commit}: selected commit to checkout
#   ${confirm}: confirm status of the user
# Arguments
#   -h|--help: show help message
#   -s|--select: search all files instead of just the modified files
#   -b|--branch: search branch and checkout branch
#   -c|--commit: search commit and checkout commit

set -e
set -f

mydir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
source "${mydir}"/../helper/set_variable.sh
source "${mydir}"/../helper/get_confirmation.sh
source "${mydir}"/../helper/git_query.sh

function usage() {
  echo -e "Usage: dotbare fcheckout [-h] [-s] [-b] [-c] [-y] ...

Select files/commit/branch through fzf and checkout the selected objects.
Files: checkout the version in HEAD or in a specific commit (reset files content back to the selected commit).
Branch: switch to the selected branch.
Commit: switch to a specific commit.

Default: list all modified files and reset selected files back to HEAD.

Optional arguments:
  -h, --help\t\tshow this help message and exit.
  -s, --select\t\tlist all tracked files and select a commit to checkout the selected files.
  -b, --branch\t\tlist all branch and checkout/switch the selected branch.
  -c, --commit\t\tlist all commits and checkout selected commit.
  -y, --yes\t\tacknowledge all actions that will be taken and skip confirmation."
}

action_type="modified"
selected_files=()
confirm=""
selected_commit=""
selected_branch=""

while [[ "$#" -gt 0 ]]; do
  case "$1" in
    -s|--select)
      action_type="select"
      shift
      ;;
    -b|--branch)
      action_type="branch"
      shift
      ;;
    -c|--commit)
      action_type="commit"
      shift
      ;;
    -y|--yes)
      confirm="y"
      shift
      ;;
    -h|--help)
      usage
      exit 0
      ;;
    *)
      echo "Invalid option: $1" >&2
      usage
      exit 1
      ;;
  esac
done

if [[ "${action_type}" == "branch" ]]; then
  # checkout branch
  selected_branch=$(get_branch 'select a branch to checkout')
  [[ -z "${selected_branch}" ]] && exit 1
  git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" checkout "${selected_branch}"
elif [[ "${action_type}" == "commit" ]]; then
  # checkout commit
  selected_commit=$(get_commit 'select a commit to checkout')
  [[ -z "${selected_commit}" ]] && exit 1
  git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" checkout "${selected_commit}"
elif [[ "${action_type}" == "modified" ]]; then
  # checkout modified file back to version in HEAD
  while IFS= read -r line; do
    selected_files+=("${line}")
  done < <(get_modified_file 'select files to checkout version in HEAD')
  [[ "${#selected_files[@]}" -eq 0 ]] && exit 1
  [[ -z "${confirm}" ]] && echo "(dryrun) dotbare checkout --" "${selected_files[@]}"
  [[ -z "${confirm}" ]] && confirm=$(get_confirmation "Confirm?")
  [[ "${confirm}" != 'y' ]] && exit 1
  git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" checkout -- "${selected_files[@]}"
elif [[ "${action_type}" == "select" ]]; then
  # checkout selected files to a selected commit
  while IFS= read -r line; do
    selected_files+=("${line}")
  done < <(get_git_file 'select files to checkout to previous commit')
  [[ "${#selected_files[@]}" -eq 0 ]] && exit 1
  # continue select a commit and then checkout the file back to the selected commit
  selected_commit=$(get_commit 'select the target commit' "${selected_files[@]}")
  [[ -z "${selected_commit}" ]] && exit 1
  [[ -z "${confirm}" ]] && echo "(dryrun) dotbare checkout ${selected_commit} --" "${selected_files[@]}"
  [[ -z "${confirm}" ]] && confirm=$(get_confirmation "Confirm?")
  [[ "${confirm}" != 'y' ]] && exit 0
  git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" checkout "${selected_commit}" "${selected_files[@]}"
fi