#!/usr/bin/env bash
# sync-src: Parallel Git status checker and fast-forward puller for ~/src
set -euo pipefail

SRC_DIR="${1:-$HOME/src}"

if [ ! -d "$SRC_DIR" ]; then
    echo "Directory $SRC_DIR does not exist." >&2
    exit 1
fi

check_repo() {
    local dir="$1"
    cd "$dir"
    local name
    name=$(basename "$dir")

    # Silently fetch upstream
    git fetch -q --all --prune 2>/dev/null || true

    local dirty=""
    if ! git diff-index --quiet HEAD -- 2>/dev/null || [ -n "$(git status --porcelain 2>/dev/null)" ]; then
        dirty=" [DIRTY: uncommitted changes]"
    fi

    local upstream="@{u}"
    local local_rev remote_rev base_rev status
    if local_rev=$(git rev-parse @ 2>/dev/null) && remote_rev=$(git rev-parse "$upstream" 2>/dev/null); then
        base_rev=$(git merge-base @ "$upstream" 2>/dev/null || true)
        if [ "$local_rev" = "$remote_rev" ]; then
            status="UP-TO-DATE"
        elif [ "$local_rev" = "$base_rev" ]; then
            status="BEHIND"
            # Auto-pull clean repos
            if [ -z "$dirty" ]; then
                if git pull -q --ff-only 2>/dev/null; then
                    status="PULLED"
                fi
            fi
        elif [ "$remote_rev" = "$base_rev" ]; then
            status="AHEAD"
        else
            status="DIVERGED"
        fi
    else
        status="NO-UPSTREAM"
    fi

    printf "%-30s : %-15s%s\n" "$name" "$status" "$dirty"
}
export -f check_repo

echo "== Scanning repositories in $SRC_DIR =="
find "$SRC_DIR" -maxdepth 3 -name ".git" -type d 2>/dev/null | sed 's|/\.git$||' | sort -u | parallel -j 8 --keep-order check_repo {}