#!/usr/bin/env bash
# sync-init-export.sh — Create a full bootstrap bundle so the other machine can
#                       clone the repo from scratch via the shared folder.
#
# Usage:  ./sync-init-export.sh [<share-dir>]
# Default share dir: $SYNC_SHARE or ~/fifiletrans
#
# Places in the shared folder:
#   <repo>-INIT-from-<host>-<timestamp>.bundle   complete git history, all branches
#   sync-push.sh                                 (copy of this repo's sync scripts)
#   sync-pull.sh
#   sync-init-import.sh
#
# The receiving side runs sync-init-import.sh from the shared folder.
# After that, both sides are identical and ready to use sync-push / sync-pull.

set -euo pipefail

# ── Config ────────────────────────────────────────────────────────────────────
SHARE_DIR="${1:-${SYNC_SHARE:-$HOME/fifiletrans}}"
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

# ── Sanity checks ─────────────────────────────────────────────────────────────
if ! git rev-parse --git-dir &>/dev/null; then
    echo "ERROR: Not inside a git repository." >&2
    exit 1
fi

REPO_ROOT=$(git rev-parse --show-toplevel)
REPO_NAME=$(basename "$REPO_ROOT")
HOST=$(hostname -s)
TIMESTAMP=$(date +%Y%m%d-%H%M%S)

BUNDLE_FILE="${REPO_NAME}-INIT-from-${HOST}-${TIMESTAMP}.bundle"
BUNDLE_PATH="${SHARE_DIR}/${BUNDLE_FILE}"

mkdir -p "$SHARE_DIR"

# ── Warn if an INIT bundle already exists for this repo ───────────────────────
EXISTING=$(find "$SHARE_DIR" -maxdepth 1 -name "${REPO_NAME}-INIT-from-*.bundle" 2>/dev/null | sort)
if [ -n "$EXISTING" ]; then
    echo "Warning: existing INIT bundle(s) found in $SHARE_DIR:"
    echo "$EXISTING" | sed 's/^/  /'
    echo ""
    read -rp "Continue and create a new one? [y/N] " ans
    ans="${ans:-N}"
    [[ "$ans" =~ ^[Yy] ]] || exit 0
fi

# ── Show what will be bundled ──────────────────────────────────────────────────
echo "Repository : $REPO_NAME"
echo "Host       : $HOST"
echo "Mode       : FULL (all branches, complete history)"
echo ""

BRANCHES=()
while IFS= read -r b; do
    BRANCHES+=("$b")
done < <(git branch --format='%(refname:short)')

for branch in "${BRANCHES[@]}"; do
    count=$(git log --oneline "$branch" | wc -l)
    tip=$(git log -1 --format="%h %s" "$branch")
    echo "  $branch : $count commit(s)  [tip: $tip]"
done
echo ""

# ── Create the full bundle ────────────────────────────────────────────────────
echo "Creating bundle..."
git bundle create "$BUNDLE_PATH" --all

SIZE=$(du -sh "$BUNDLE_PATH" | cut -f1)
echo "Bundle     : $BUNDLE_PATH ($SIZE)"

# ── Copy sync scripts into the shared folder ──────────────────────────────────
echo ""
echo "Copying sync scripts to shared folder..."

SCRIPTS=("sync-push.sh" "sync-pull.sh" "sync-init-import.sh")
for script in "${SCRIPTS[@]}"; do
    src="${SCRIPT_DIR}/${script}"
    if [ -f "$src" ]; then
        cp "$src" "${SHARE_DIR}/${script}"
        chmod +x "${SHARE_DIR}/${script}"
        echo "  Copied : $script"
    else
        echo "  WARNING: $script not found at $src — skipping." >&2
    fi
done

# ── Write a HOWTO marker file ─────────────────────────────────────────────────
HOWTO="${SHARE_DIR}/INIT-HOWTO-${REPO_NAME}.txt"
cat > "$HOWTO" <<EOF
Bootstrap instructions for: $REPO_NAME
Generated : $(date)
From host : $HOST
Bundle    : $BUNDLE_FILE

On the receiving machine:
  1. Make sure this folder ($(basename "$SHARE_DIR")) is accessible at the same path,
     or adjust the path in the command below.

  2. Run:
       bash ${SHARE_DIR}/sync-init-import.sh ${SHARE_DIR} /path/to/new/repo

  3. After the import completes, both machines are in sync.
     Use sync-push.sh and sync-pull.sh for ongoing updates.
EOF
echo "  Written : $(basename "$HOWTO")"

# ── Done ───────────────────────────────────────────────────────────────────────
echo ""
echo "Shared folder contents:"
ls -lh "$SHARE_DIR" | grep -E "(${REPO_NAME}|sync-)" | sed 's/^/  /'
echo ""
echo "On the other machine, run:"
echo "  bash ${SHARE_DIR}/sync-init-import.sh ${SHARE_DIR} /path/to/new/$(basename "$REPO_ROOT")"