#!/bin/bash
#
# helper functions to obtain git related information

#######################################
# let user select a commit interactively
# Arguments:
#   $1: the helper message to display in the fzf header
#   $2: files to show diff against HEAD
# Outputs:
#   the selected commit 6 char code
#   e.g. b60b330
#######################################
function get_commit() {
  local header="${1:-select a commit}"
  local files="$2"
  if [[ -z "${files}" ]]; then
    /usr/bin/git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" \
    log --oneline --color=always --decorate=short \
      | fzf --no-multi --header="${header}" \
        --preview "echo {} \
          | awk '{print \$1}' \
          | xargs -I __ /usr/bin/git --git-dir=${DOTBARE_DIR} --work-tree=${DOTBARE_TREE} \
            show --color=always  __" \
      | awk '{print $1}'
  else
    /usr/bin/git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" \
    log --oneline --color=always --decorate=short \
      | fzf --no-multi --header="${header}" --preview "echo {} \
          | awk '{print \$1}' \
          | xargs -I __ /usr/bin/git --git-dir=${DOTBARE_DIR} --work-tree=${DOTBARE_TREE} \
            diff --color=always __ $files" \
      | awk '{print $1}'
  fi
}

#######################################
# let user select a branch interactively
# Arguments:
#   $1: the helper message to display in the fzf header
# Outputs:
#   the selected branch name
#   e.g. master
#######################################
function get_branch() {
  local header="${1:-select a branch}"
  /usr/bin/git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" branch -a \
    | awk '{
        if ($0 ~ /\*.*\(HEAD.*/) {
          gsub(/\* /, "", $0)
          print "\033[32m" $0 "\033[0m"
        } else if (match($1, "\\*") != 0) {
          print "\033[32m" $2 "\033[0m"
        } else if ($0 ~ /^[ \t]+remotes\/.*/) {
          gsub(/[ \t]+/, "", $0)
          print "\033[31m" $0 "\033[0m"
        } else {
          gsub(/^[ \t]+/, "", $0)
          print $0
        }
      }' \
    | fzf --no-multi --header="${header}" \
      --preview="/usr/bin/git --git-dir=${DOTBARE_DIR} --work-tree=${DOTBARE_TREE} \
      log --oneline --graph --color=always --decorate=short {}"
}

#######################################
# let user select a dotbare tracked file interactively
# Arguments:
#   $1: the helper message to display in the fzf header
#   $2: if exist, don't do multi selection, do single
# Outputs:
#   the selected file path
#   e.g.$HOME/.config/nvim/init.vim
#######################################
function get_git_file() {
  local header="${1:-select tracked file}"
  set_fzf_multi "$2"
  /usr/bin/git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" \
  ls-files --full-name --directory "${DOTBARE_TREE}" \
    | fzf --header="${header}" \
      --preview "head -50 ${DOTBARE_TREE}/{}" \
    | awk -v home="${DOTBARE_TREE}" '{print home "/" $0}'
}

#######################################
# let user select a modified file interactively
# Arguments:
#   $1: the helper message to display in the fzf header
#   $2: display mode of modified files.
#     default: true
#     all: display all modified, include staged and unstaged
#     staged: display only staged files
#     unstaged: display only unstaged files
#   $3: output_format
#     default: name
#     name: formatted name of the file
#     raw: raw file name with status
#   $3: if exists, don't do multi selection, do single
# Outputs:
#   the selected file path
#   e.g.$HOME/.config/nvim/init.vim
#######################################
function get_modified_file() {
  local header="${1:-select a modified file}"
  local display_mode="${2:-all}"
  local output_format="${3:-name}"
  set_fzf_multi "$4"
  /usr/bin/git --git-dir="${DOTBARE_DIR}" --work-tree="${DOTBARE_TREE}" \
  status --porcelain \
    | awk -v display_mode="${display_mode}" '{
        if ($0 ~ /^[A-Za-z][A-Za-z].*$/) {
          print "\033[32m" substr($0, 1, 1) "\033[31m" substr($0, 2) "\033[0m"
        } else if ($0 ~ /^[A-Za-z][ \t].*$/) {
          if (display_mode == "all" || display_mode == "staged") {
            print "\033[32m" $0 "\033[0m"
          }
        } else {
          if (display_mode == "all" || display_mode == "unstaged") {
            print "\033[31m" $0 "\033[0m"
          }
        }
      }' \
    | fzf --header="${header}" --preview "echo {} \
        | awk '{print \$2}' \
        | xargs -I __ /usr/bin/git --git-dir=${DOTBARE_DIR} --work-tree=${DOTBARE_TREE} \
          diff HEAD --color=always ${DOTBARE_TREE}/__" \
    | awk -v home="${DOTBARE_TREE}" -v format="${output_format}" '{
        if (format == "name") {
          print home "/" $2
        } else {
          print $0
        }
      }'
}