#
# Displays Git repository information.
#
# Authors:
#   Sorin Ionescu <sorin.ionescu@gmail.com>
#

# Gets the path to the Git directory.
function _git-dir() {
  local git_root="$(git-root)"
  local git_dir_or_file="${git_root}/.git"
  local git_dir

  if [[ ! -d "$git_root" ]]; then
    return 1
  fi

  if [[ -f "$git_dir_or_file" ]]; then
    git_dir="${${${$(<"$git_dir_or_file")}[(fr)gitdir:*]}#gitdir: }"
  else
    git_dir="$git_dir_or_file"
  fi

  if [[ -d "$git_dir" ]]; then
    print "$git_dir"
    return 0
  fi

  return 1
}

# Gets the Git special action (am, merge, rebase, etc.).
# Borrowed from vcs_info and edited.
function _git-action() {
  local action=''
  local action_dir
  local git_dir="$(_git-dir)"

  for action_dir in \
    "${git_dir}/rebase-apply" \
    "${git_dir}/rebase" \
    "${git_dir}/../.dotest"; do
    if [[ -d "$action_dir" ]] ; then
      if [[ -f "${action_dir}/rebasing" ]] ; then
        action='rebase'
      elif [[ -f "${action_dir}/applying" ]] ; then
        action='am'
      else
        action='am/rebase'
      fi
      print "$action"
      return 0
    fi
  done

  for action_dir in \
    "${git_dir}/rebase-merge/interactive" \
    "${git_dir}/.dotest-merge/interactive"; do
    if [[ -f "$action_dir" ]]; then
      print 'rebase-i'
      return 0
    fi
  done

  for action_dir in \
    "${git_dir}/rebase-merge" \
    "${git_dir}/.dotest-merge"; do
    if [[ -d "$action_dir" ]]; then
      print 'rebase-m'
      return 0
    fi
  done

  if [[ -f "${git_dir}/MERGE_HEAD" ]]; then
    print 'merge'
    return 0
  fi

  if [[ -f "${git_dir}/CHERRY_PICK_HEAD" ]]; then
    print 'cherry-pick'
    return 0
  fi

  if [[ -f "${git_dir}/BISECT_LOG" ]]; then
    print 'bisect'
    return 0
  fi

  return 1
}

# Turns off git-info for the current repository.
function _git-info-abort() {
  if ! is-true "$_git_info_executing"; then
    return 1
  fi

  cat >&2 <<EOF


Gathering status for certain repositories is time intensive.
By pressing CTRL + C, you have turned off prompt Git status
for this repository.

To revert, execute:
  git-info on

EOF

  unset _git_info_executing
  git config --bool prompt.showinfo false
  git-info
  return 0
}
add-zsh-trap INT _git-info-abort

# Gets the Git status information.
function git-info() {
  # Extended globbing is needed to parse repository status.
  setopt LOCAL_OPTIONS
  setopt EXTENDED_GLOB

  local action
  local action_format
  local action_formatted
  local added=0
  local added_format
  local added_formatted
  local ahead
  local ahead_format
  local ahead_formatted
  local ahead_or_behind
  local behind
  local behind_format
  local behind_formatted
  local branch
  local branch_info
  local branch_format
  local branch_formatted
  local clean
  local clean_formatted
  local commit
  local commit_short
  local commit_format
  local deleted=0
  local deleted_format
  local deleted_formatted
  local dirty=0
  local dirty_format
  local dirty_formatted
  local line_number=0
  local modified=0
  local modified_format
  local modified_formatted
  local remote
  local remote_format
  local remote_formatted
  local renamed=0
  local renamed_format
  local renamed_formatted
  local commit_formatted
  local stashed=0
  local stashed_format
  local stashed_formatted
  local unmerged=0
  local unmerged_format
  local unmerged_formatted
  local untracked=0
  local untracked_format
  local untracked_formatted
  local prompt
  local rprompt
  local git_info_var
  local -A git_info_vars
  local status_cmd
  local ignore_submodule
  local ignore_submodule_when

  # Clean up previous Git info.
  unset git_prompt_info
  unset git_rprompt_info

  # Return if not inside a Git repository work tree.
  if ! is-true "$(git rev-parse --is-inside-work-tree 2>/dev/null)"; then
    return 1
  fi

  if (( $# > 0 )); then
    if [[ "$1" == [Oo][Nn] ]]; then
      git config --bool prompt.showinfo true
    elif [[ "$1" == [Oo][Ff][Ff] ]]; then
      git config --bool prompt.showinfo false
    else
      print "usage: $0 [ on | off ]" >&2
    fi
    return 0
  fi

  # Return if git-info is disabled.
  if ! is-true "${$(git config --bool prompt.showinfo):-true}"; then
    return 1
  fi

  # Used to abort and turn git-info off on SIGINT.
  _git_info_executing=true

  # Use short status for easy parsing.
  status_cmd='git status --short --branch'

  # Ignore submodule status.
  zstyle -b \
    ':omz:plugin:git:prompt:ignore' submodule 'ignore_submodule'
  zstyle -s \
    ':omz:plugin:git:prompt:ignore:submodule' when 'ignore_submodule_when'
  if is-true "$ignore_submodule"; then
    status_cmd+=" --ignore-submodules=${ignore_submodule_when:-all}"
  fi

  # Get commit.
  commit="$(git rev-parse HEAD 2>/dev/null)"

  # Format commit (short).
  commit_short="$commit[1,7]"
  zstyle -s ':omz:plugin:git:prompt' commit 'commit_format'
  zformat -f commit_formatted "$commit_format" "c:$commit_short"

  # Stashed
  if [[ -f "$(_git-dir)/refs/stash" ]]; then
    stashed="$(git stash list 2>/dev/null | wc -l)"
    zstyle -s ':omz:plugin:git:prompt' stashed 'stashed_format'
    zformat -f stashed_formatted "$stashed_format" "S:$stashed"
  fi

  # Assume that the working copy is clean.
  zstyle -s ':omz:plugin:git:prompt' clean 'clean_formatted'

  while IFS=$'\n' read line; do
    (( line_number++ ))

    if (( line_number == 1 )) && [[ "$line" == *'(no branch)'* ]]; then
      # Set branch to commit (short) when the branch is not found.
      branch="$commit_short"

      # Get action.
      action="$(_git-action)"
      if [[ -n "$action" ]]; then
        zstyle -s ':omz:plugin:git:prompt' action 'action_format'
        zformat -f action_formatted "$action_format" "s:$action"
      fi
    elif (( line_number == 1 )) \
      && [[ "$line" == (#b)'## Initial commit on '(?##) ]];
    then
      branch="$match[1]"
    elif (( line_number == 1 )); then
      # Split the line into an array for parsing.
      branch_info=(${(s: :)line})

      # Match: master...origin/master
      if [[ "$branch_info[2]" == (#b)(?##)...(?##/?##) ]]; then
        branch="$match[1]"
        remote="$match[2]"

        # Match: [ahead or [behind
        if [[ "$branch_info[3]" == (#b)\[(ahead|behind) ]]; then
          ahead_or_behind="$match[1]"
          if [[ "$ahead_or_behind" == 'behind' ]]; then
            # Extract digits: 10]
            behind="${branch_info[4]%\]}"
          else
            # Extract digits: 10] or 10,
            ahead="${branch_info[4]%[,\]]}"
            # Extract digits: 10]
            behind="${branch_info[6]%\]}"
          fi
        fi
      # Match: master
      elif [[ "$branch_info[2]" == (#b)(?##) ]]; then
        branch="$match[1]"
      fi
    else
      # Count: added/deleted/modified/renamed/unmerged/untracked
      # T (type change) is undocumented, see https://raw.github.com/gitster/git/master/Documentation/RelNotes/1.7.8.2.txt
      [[ "$line" == [AMDCT][MD\ ]\ * ]] && (( added++ ))
      [[ "$line" == [\ MARC]D\ * ]] && (( deleted++ ))
      [[ "$line" == ?[MT]\ * ]] && (( modified++ ))
      [[ "$line" == R?\ * ]] && (( renamed++ ))
      [[ "$line" == (?U|U?|AA|DD)\ * ]] && (( unmerged++ ))
      [[ "$line" == \?\?\ * ]] && (( untracked++ ))
      (( dirty++ ))
    fi
  done < <("${(z)status_cmd}" 2>/dev/null)

  # Format branch.
  zstyle -s ':omz:plugin:git:prompt' branch 'branch_format'
  zformat -f branch_formatted "$branch_format" "b:$branch"

  # Format remote.
  if [[ "$branch" != "$commit" ]]; then
    if [[ -z "$remote" ]]; then
      remote="${$( \
        git rev-parse \
          --verify ${branch}@{upstream} \
          --symbolic-full-name 2>/dev/null)#refs/remotes/}"
    fi
    zstyle -s ':omz:plugin:git:prompt' remote 'remote_format'
    zformat -f remote_formatted "$remote_format" "R:$remote"
  fi

  # Format ahead.
  if [[ -n "$ahead" ]]; then
    zstyle -s ':omz:plugin:git:prompt' ahead 'ahead_format'
    zformat -f ahead_formatted "$ahead_format" "A:$ahead"
  fi

  # Format behind.
  if [[ -n "$behind" ]]; then
    zstyle -s ':omz:plugin:git:prompt' behind 'behind_format'
    zformat -f behind_formatted "$behind_format" "B:$behind"
  fi

  # Format added.
  if (( $added > 0 )); then
    zstyle -s ':omz:plugin:git:prompt' added 'added_format'
    zformat -f added_formatted "$added_format" "a:$added_format"
  fi

  # Format deleted.
  if (( $deleted > 0 )); then
    zstyle -s ':omz:plugin:git:prompt' deleted 'deleted_format'
    zformat -f deleted_formatted "$deleted_format" "d:$deleted_format"
  fi

  # Format modified.
  if (( $modified > 0 )); then
    zstyle -s ':omz:plugin:git:prompt' modified 'modified_format'
    zformat -f modified_formatted "$modified_format" "m:$modified"
  fi

  # Format renamed.
  if (( $renamed > 0 )); then
    zstyle -s ':omz:plugin:git:prompt' renamed 'renamed_format'
    zformat -f renamed_formatted "$renamed_format" "r:$renamed"
  fi

  # Format unmerged.
  if (( $unmerged > 0 )); then
    zstyle -s ':omz:plugin:git:prompt' unmerged 'unmerged_format'
    zformat -f unmerged_formatted "$unmerged_format" "U:$unmerged"
  fi

  # Format untracked.
  if (( $untracked > 0 )); then
    zstyle -s ':omz:plugin:git:prompt' untracked 'untracked_format'
    zformat -f untracked_formatted "$untracked_format" "u:$untracked"
  fi

  # Format dirty.
  if (( $dirty > 0 )); then
    zstyle -s ':omz:plugin:git:prompt' dirty 'dirty_format'
    zformat -f dirty_formatted "$dirty_format" "D:$dirty"
    unset clean_formatted
  fi

  # Format prompts.
  zstyle -s ':omz:plugin:git:prompt' prompt 'prompt_format'
  zstyle -s ':omz:plugin:git:prompt' rprompt 'rprompt_format'

  git_info_vars=(
    git_prompt_info "$prompt_format"
    git_rprompt_info "$rprompt_format"
  )

  for git_info_var in ${(k)git_info_vars}; do
    zformat -f "$git_info_var" "$git_info_vars[$git_info_var]" \
      "s:$action_formatted" \
      "a:$added_formatted" \
      "A:$ahead_formatted" \
      "B:$behind_formatted" \
      "b:$branch_formatted" \
      "C:$clean_formatted" \
      "c:$commit_formatted" \
      "d:$deleted_formatted" \
      "D:$dirty_formatted" \
      "m:$modified_formatted" \
      "R:$remote_formatted" \
      "r:$renamed_formatted" \
      "S:$stashed_formatted" \
      "U:$unmerged_formatted" \
      "u:$untracked_formatted"
  done

  unset _git_info_executing
  return 0
}

git-info "$@"