#!/usr/bin/env bash
# git-sync — add/commit/pull --rebase/push a single repo.
# Safe: rebases onto remote, never merges, never force-pushes; conflicts are
# reported (rebase aborted), not auto-resolved.
# Usage: git-sync <dir> [commit-message]
# Invoked by the /git-sync slash command, once per configured project repo.
set -uo pipefail

dir=${1:?usage: git-sync <dir> [message]}
msg=${2:-}

# expand leading ~ (not expanded inside variables) so $HOME-based paths work
case "$dir" in
  "~")    dir="$HOME" ;;
  "~/"*)  dir="$HOME/${dir#"~/"}" ;;
esac

ok()   { printf '\033[1;32m✓ %s\033[0m\n' "$*"; }   # green
note() { printf '\033[1;36m· %s\033[0m\n' "$*"; }   # cyan
warn() { printf '\033[1;33m⚠ %s\033[0m\n' "$*"; }   # yellow

g() { git -C "$dir" "$@"; }
label=$(basename "$dir")

if ! g rev-parse --is-inside-work-tree >/dev/null 2>&1; then
  warn "$label: kein Git-Repo — übersprungen."
  exit 0
fi
branch=$(g rev-parse --abbrev-ref HEAD)

# --- commit working-tree changes -------------------------------------------
if [[ -n "$(g status --porcelain)" ]]; then
  g add -A
  [[ -z "$msg" ]] && msg="git-sync: $(date '+%Y-%m-%d %H:%M')"
  if g commit --quiet -m "$msg"; then
    note "$label: committed — $msg"
  else
    warn "$label: commit fehlgeschlagen."
    exit 0
  fi
else
  note "$label: keine Änderungen."
fi

# --- pull --rebase, then push (no force, no merge) -------------------------
if ! g remote get-url origin >/dev/null 2>&1; then
  note "$label: kein origin-Remote — push übersprungen."
  exit 0
fi

if g rev-parse --abbrev-ref --symbolic-full-name '@{u}' >/dev/null 2>&1; then
  # integrate remote first: rebase keeps history linear, no merge commits
  g fetch --quiet 2>/dev/null || true
  behind=$(g rev-list --count 'HEAD..@{u}' 2>/dev/null || echo 0)
  if [[ "$behind" -gt 0 ]]; then
    if g pull --rebase --quiet 2>/dev/null; then
      note "$label: $behind Commit(s) per Rebase integriert."
    else
      g rebase --abort >/dev/null 2>&1 || true
      warn "$label: Pull/Rebase-Konflikt — bitte manuell lösen. Push übersprungen."
      exit 0
    fi
  fi
  ahead=$(g rev-list --count '@{u}..HEAD' 2>/dev/null || echo 0)
  if [[ "$ahead" -eq 0 ]]; then
    note "$label: nichts zu pushen."
  elif g push --quiet 2>/dev/null; then
    ok "$label: $ahead Commit(s) gepusht ($branch)."
  else
    warn "$label: push abgelehnt — Remote voraus. Manuell prüfen."
  fi
else
  if g push --quiet -u origin "$branch" 2>/dev/null; then
    ok "$label: Upstream gesetzt und gepusht ($branch)."
  else
    warn "$label: kein Upstream, push fehlgeschlagen — einmal manuell pushen."
  fi
fi