.prompt_command

#!/usr/bin/env bash
# vim: set noexpandtab:
# configure bash prompt with git info

# forked from https://github.com/twolfson/sexy-bash-prompt (MIT)
# afirth 2018

# set -ux

source .prompt_colors

PROMPT_COMMAND=prompt_command

# Define the prompt
function prompt_command() {
	retval=$?
	history -a

	# exit status, time, user, host, directory
	PS1="\[$txtrst\]$(prompt_get_exit_status) [\t] \u@\h \w\[$txtrst\]"

	# git info
	if prompt_is_on_git; then
		PS1="${PS1} \[$txtcyn\]$(prompt_get_git_info)\[$txtylw\]$(prompt_get_git_progress)"
	fi

	# new line, prompt, and clear format
	PS1="${PS1} \n\[$txtrst\]\[$txtcyn\]\$ \[$txtrst\]"

	export PS1
}

# Set up symbols
prompt_synced_symbol="👌"
prompt_dirty_synced_symbol="*"
prompt_unpushed_symbol="△"
prompt_dirty_unpushed_symbol="▲"
prompt_unpulled_symbol="▽"
prompt_dirty_unpulled_symbol="▼"
prompt_unpushed_unpulled_symbol="⬡"
prompt_dirty_unpushed_unpulled_symbol="⬢"

function prompt_get_git_branch() {
	# On branches, this will return the branch name
	# On non-branches, (no branch)
	ref=$(git symbolic-ref HEAD --short 2> /dev/null)
	if [[ "$ref" != "" ]]; then
		echo "$ref"
	else
		echo "(no branch)"
	fi
}

function prompt_get_exit_status() {
	if [[ $retval -eq 0 ]]; then
		echo -n "✓"
	else
		echo -n "❌($retval)"
	fi
}

function prompt_get_git_progress() {
	# Detect in-progress actions (e.g. merge, rebase)
	# https://github.com/git/git/blob/v1.9-rc2/wt-status.c#L1199-L1241
	git_dir="$(git rev-parse --git-dir)"

	# git merge
	if [[ -f "$git_dir/MERGE_HEAD" ]]; then
		echo " [merge]"
	elif [[ -d "$git_dir/rebase-apply" ]]; then
		# git am
		if [[ -f "$git_dir/rebase-apply/applying" ]]; then
			echo " [am]"
		# git rebase
		else
			echo " [rebase]"
		fi
	elif [[ -d "$git_dir/rebase-merge" ]]; then
		# git rebase --interactive/--merge
		echo " [rebase]"
	elif [[ -f "$git_dir/CHERRY_PICK_HEAD" ]]; then
		# git cherry-pick
		echo " [cherry-pick]"
	fi
	if [[ -f "$git_dir/BISECT_LOG" ]]; then
		# git bisect
		echo " [bisect]"
	fi
	if [[ -f "$git_dir/REVERT_HEAD" ]]; then
		# git revert --no-commit
		echo " [revert]"
	fi
}

prompt_is_branch1_behind_branch2 () {
	#			Unsynced commit

	# Find the first log (if any) that is in branch1 but not branch2
	first_log="$(git log $1..$2 -1 2> /dev/null)"

	# Exit with 0 if there is a first log, 1 if there is not
	[[ -n "$first_log" ]]
}

prompt_branch_exists () {
	# List remote branches					 | # Find our branch and exit with 0 or 1 if found/not found
	git branch --remote 2> /dev/null | grep --quiet "$1"
}

prompt_parse_git_ahead () {
	# Grab the local and remote branch
	branch="$(prompt_get_git_branch)"
	remote="$(git config --get "branch.${branch}.remote" || echo -n "origin")"
	remote_branch="$remote/$branch"

	# If the remote branch is behind the local branch
	# or it has not been merged into origin (remote branch doesn't exist)
	if (prompt_is_branch1_behind_branch2 "$remote_branch" "$branch" ||
			! prompt_branch_exists "$remote_branch"); then
		# echo our character
		echo 1
	fi
}

prompt_parse_git_behind () {
	# Grab the branch
	branch="$(prompt_get_git_branch)"
	remote="$(git config --get "branch.${branch}.remote" || echo -n "origin")"
	remote_branch="$remote/$branch"

	# If the local branch is behind the remote branch
	if prompt_is_branch1_behind_branch2 "$branch" "$remote_branch"; then
		# echo our character
		echo 1
	fi
}

function prompt_parse_git_dirty() {
	# If the git status has *any* changes (e.g. dirty), echo our character
	if [[ -n "$(git status --porcelain 2> /dev/null)" ]]; then
		echo 1
	fi
}

function prompt_is_on_git() {
	git rev-parse &> /dev/null
}

function prompt_get_git_status() {
	# Grab the git dirty and git behind
	dirty_branch="$(prompt_parse_git_dirty)"
	branch_ahead="$(prompt_parse_git_ahead)"
	branch_behind="$(prompt_parse_git_behind)"

	# Iterate through all the cases and if it matches, then echo
	if [[ "$dirty_branch" == 1 && "$branch_ahead" == 1 && "$branch_behind" == 1 ]]; then
		echo "$prompt_dirty_unpushed_unpulled_symbol"
	elif [[ "$branch_ahead" == 1 && "$branch_behind" == 1 ]]; then
		echo "$prompt_unpushed_unpulled_symbol"
	elif [[ "$dirty_branch" == 1 && "$branch_ahead" == 1 ]]; then
		echo "$prompt_dirty_unpushed_symbol"
	elif [[ "$branch_ahead" == 1 ]]; then
		echo "$prompt_unpushed_symbol"
	elif [[ "$dirty_branch" == 1 && "$branch_behind" == 1 ]]; then
		echo "$prompt_dirty_unpulled_symbol"
	elif [[ "$branch_behind" == 1 ]]; then
		echo "$prompt_unpulled_symbol"
	elif [[ "$dirty_branch" == 1 ]]; then
		echo "$prompt_dirty_synced_symbol"
	else # clean
		echo "$prompt_synced_symbol"
	fi
}

prompt_get_git_info () {
	# Grab the branch
	branch="$(prompt_get_git_branch)"

	# If there are any branches
	if [[ "$branch" != "" ]]; then
		# Echo the branch
		output="$branch"

		# Add on the git status
		output="$output$(prompt_get_git_status)"

		# Echo our output
		echo "$output"
	fi
}