gis/gis

#!/usr/bin/env bash

# Text formatting variables
text_reset=$'\e[0m'
text_bold=$'\e[1m'
text_blue=$'\e[34m'
text_green=$'\e[32m'
text_magenta=$'\e[35m'
text_red=$'\e[31m'
text_yellow=$'\e[33m'

function print_usage {
    cat <<EOF
Usage: gis [OPTIONS] [COMMAND]

Show a status summary of all Git repositories which are found recursively in
current work directory. If the colon-separated environment variable \$GIS_PATH
is set, the declared directories will be used instead.

COMMANDS
  fetch  Execute 'git fetch --prune --all' for all found repositories
  pull   Execute 'git pull' for all found repositories which are behind
         upstream, includes 'gis fetch'

OPTIONS
  -p, --path  PATH  Use PATH for searching Git repositories
  -h, --help        Show this help message and exit
EOF
}

function error {
    echo -e "${text_bold}${text_red}ERROR${text_reset} $1\n"
    print_usage
    exit 1
}

# Parse arguments
fetch=false
pull=false
while (( "$#" )); do
    case "$1" in
        -p|--path)
            if [ -n "$2" ] && [ "${2:0:1}" != "-" ]; then
                paths+=("$(realpath "$2")")
                shift 2
            else
                error "Argument for ${text_bold}$1${text_reset} is missing"
            fi
            ;;
        -h|--help)
            print_usage
            exit 0
            ;;
        -*)
            error "Unsupported option ${text_bold}$1${text_bold}"
            ;;
        fetch)
            fetch=true
            shift
            ;;
        f*)
            error "Unsupported command ${text_bold}$1${text_reset}, did you mean ${text_bold}fetch${text_reset}?"
            ;;
        pull)
            fetch=true
            pull=true
            shift
            ;;
        p*)
            error "Unsupported command ${text_bold}$1${text_reset}, did you mean ${text_bold}pull${text_reset}?"
            ;;
        *)
            error "Unsupported command ${text_bold}$1${text_reset}"
            ;;
    esac
done

# Add $GIS_PATH, current Git repository or current work directory to paths if none is given
if [ "${paths[*]}" == "" ]; then
    if [ "$GIS_PATH" ]; then
        OLDIFS=$IFS
        IFS=":" read -r -a paths <<< "$GIS_PATH"
        IFS=$OLDIFS
    else
        paths=("$(pwd)")
    fi
fi

# Find Git repositories
git_dirs=()
for path in "${paths[@]}"; do
    readarray -t found_git_dirs < <(find "$path" -type d -name ".git" -exec dirname {} \; | sort)

    # Check if inside of a repository if none found
    if [ "${#found_git_dirs[@]}" -eq 0 ]; then
        if git rev-parse > /dev/null 2>&1; then
            found_git_dirs+=("$(git rev-parse --show-toplevel)")
        fi
    fi

    git_dirs+=("${found_git_dirs[@]}")
done

# Fetch Git repositories
if [ "$fetch" == true ]; then

    if [ "${#git_dirs[@]}" -eq 1 ]; then
        suffix="y"
    else
        suffix="ies"
    fi
    echo "${text_bold}${text_blue}Fetching${text_reset} ${#git_dirs[@]} repositor${suffix}"

    for dir in "${git_dirs[@]}"; do
        cd "$dir" || echo "Failed to cd into ${text_bold}${text_red}${dir}${text_reset}"

        # Get repository name
        repository_name=$(basename "$dir")

        # Fetch all Git repositories in background
        git fetch --prune --all 1> /dev/null 2>  >(trap 'kill $! 2> /dev/null' INT TERM; sed "s/^/${text_bold}${text_blue}${repository_name}${text_reset} /" >&2) &
        fetch_pids+=("$!")
    done

    for pid in "${fetch_pids[@]}"; do
        wait "$pid"
    done
    echo
fi

# Pull Git repositories
if [ "$pull" == true ]; then

    # Get Git repositories which are behind upstream
    for dir in "${git_dirs[@]}"; do
        cd "$dir" || echo "Failed to cd into ${text_bold}${text_red}${dir}${text_reset}"

        branch_status=$(git status --short --branch --porcelain | head -n 1)
        if [[ "$branch_status" =~ ^\#\#.*\[behind.*\] ]]; then
            pull_dirs+=("$dir")
        fi
    done

    if [ "${#pull_dirs[@]}" -eq 1 ]; then
        suffix="y"
    else
        suffix="ies"
    fi
    echo "${text_bold}${text_magenta}Pulling${text_reset} ${#pull_dirs[@]} repositor${suffix}"

    # Pull all Git repositories which are behind upstream in background
    for dir in "${pull_dirs[@]}"; do
        cd "$dir" || echo "Failed to cd into ${text_bold}${text_red}${dir}${text_reset}"

        # Get repository name
        repository_name=$(basename "$dir")

        git pull 1> /dev/null 2>  >(trap 'kill $! 2> /dev/null' INT TERM; sed "s/^/${text_bold}${text_magenta}${repository_name}${text_reset} /" >&2) &
        pull_pids+=("$!")
    done

    for pid in "${pull_pids[@]}"; do
        wait "$pid"
    done
    echo
fi

# Get Git status of all directories
for dir in "${git_dirs[@]}"; do
    cd "$dir" || echo "Failed to cd into ${text_bold}${text_red}${dir}${text_reset}"

    # Get repository name
    repository_name=$(basename "$dir")

    # Get current branch
    current_branch=$(git branch --show-current)

    # Get origin head
    if git symbolic-ref refs/remotes/origin/HEAD > /dev/null 2>&1; then
        [[ $(git symbolic-ref refs/remotes/origin/HEAD) =~ \/([^\/]*)$ ]] &>/dev/null && origin_head="${BASH_REMATCH[1]}"
    else
        origin_head="$current_branch"
    fi

    # Get number of additional local branches
    num_branches=$(git branch | wc -l)
    num_additional_branches=$(( num_branches - 1 ))

    status_keys=""

    # Check stash
    if [[ $(git stash list) ]]; then
        status_keys="${status_keys}\$"
    fi

    # Get status
    remote_status_keys=""
    while read -r status; do
        if [[ "$status" =~ ^\#\#.*\[(.*)\] ]]; then
            [[ "${BASH_REMATCH[1]}" == *"ahead"* ]] && [[ "${BASH_REMATCH[1]}" == *"behind"* ]] && remote_status_keys="⇕" && continue
            [[ "${BASH_REMATCH[1]}" == *"ahead"* ]] && remote_status_keys="⇡" && continue
            [[ "${BASH_REMATCH[1]}" == *"behind"* ]] && remote_status_keys="⇣" && continue
            [[ "${BASH_REMATCH[1]}" == *"gone"* ]] && remote_status_keys="✗" && continue
        elif [[ "$status" != "#"* ]]; then
            status_char="${status:0:1}"
            [[ "$status_keys" != *"$status_char"* ]] && status_keys="${status_keys}${status_char}"
        fi
    done < <(git status --short --branch --porcelain)
    status_keys="${status_keys}${remote_status_keys}"

    # Beautify status
    status_keys="${status_keys//A/+}"
    status_keys="${status_keys//D/-}"
    status_keys="${status_keys//M/!}"
    status_keys="${status_keys//U/=}"

    # Update all status keys
    all_status_keys="${all_status_keys}${status_keys}"

    # Construct key output
    if [[ "$status_keys" ]]; then
        status_keys="${text_bold}${text_red}[${status_keys}]${text_reset}"
    else
        status_keys="${text_bold}${text_green}[✓]${text_reset}"
    fi

    output="${output}${repository_name};${status_keys}"

    # Construct branch output
    if [ "$current_branch" = "$origin_head" ]; then
        output="${output};${text_bold}${current_branch}${text_reset}"
    else
        num_additional_branches=$(( num_additional_branches - 1 ))
        output="${output};${text_bold}${text_yellow}${current_branch}${text_reset} (${origin_head}${text_reset})"
    fi
    if [[ $num_additional_branches -gt 0 ]]; then
        output="${output} (+${num_additional_branches})"
    fi

    output="${output}\n"

done

# Print keys
if [[ "$all_status_keys" ]]; then
    echo "${text_bold}Status${text_reset}"
    [[ "$all_status_keys" == *"\$"* ]] && echo "  ${text_bold}${text_red}\$${text_reset} - Dirty stash"
    [[ "$all_status_keys" == *"?"* ]] && echo "  ${text_bold}${text_red}?${text_reset} - Untracked files"
    [[ "$all_status_keys" == *"!"* ]] && echo "  ${text_bold}${text_red}!${text_reset} - Local changes"
    [[ "$all_status_keys" == *"+"* ]] && echo "  ${text_bold}${text_red}+${text_reset} - Staged changes"
    [[ "$all_status_keys" == *"-"* ]] && echo "  ${text_bold}${text_red}-${text_reset} - File removed"
    [[ "$all_status_keys" == *"="* ]] && echo "  ${text_bold}${text_red}=${text_reset} - Both modified"
    [[ "$all_status_keys" == *"⇕"* ]] && echo "  ${text_bold}${text_red}⇕${text_reset} - Diverged from upstream"
    [[ "$all_status_keys" == *"⇡"* ]] && echo "  ${text_bold}${text_red}⇡${text_reset} - Ahead upstream"
    [[ "$all_status_keys" == *"⇣"* ]] && echo "  ${text_bold}${text_red}⇣${text_reset} - Behind upstream"
    [[ "$all_status_keys" == *"✗"* ]] && echo "  ${text_bold}${text_red}✗${text_reset} - Upstream gone"
    echo
fi
echo -e "$output" | column -s ";" -t