#!/bin/bash
#
# Daily backup of Signet datadir and mining wallet to git (https://git.4nkweb.com/4nk/backup).
# Runs save-signet-datadir-backup.sh and export-mining-wallet.sh, then pushes to the
# backup repo. Keeps only 2 versions of the full chain (signet-datadir) and 2 of the
# mining wallet export.
#
# Run via cron. Requires: docker (for backup scripts), git, passwordless push to backup repo.
# Log: data/backup-to-git.log
#
# Author: 4NK Team
# Date: 2026-02-04

set -e

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_DIR="$(dirname "$SCRIPT_DIR")"
BACKUP_DIR="${PROJECT_DIR}/backups"
LOG_FILE="${SCRIPT_DIR}/backup-to-git.log"
BACKUP_REPO_URL="git@git.4nkweb.com:4nk/backup.git"
BACKUP_GIT_WORKSPACE="${BACKUP_GIT_WORKSPACE:-$HOME/.4nk-backup-git}"
KEEP_VERSIONS=2

SIGNET_SUBDIR="signet-datadir"
WALLET_SUBDIR="mining-wallet"

log() { echo "$(date -Iseconds) $*" | tee -a "$LOG_FILE"; }

cd "$PROJECT_DIR" || exit 1

log "=== Backup to git cron ==="

# 1. Run signet datadir backup
if [ ! -x "${PROJECT_DIR}/save-signet-datadir-backup.sh" ]; then
  log "ERROR: save-signet-datadir-backup.sh not executable"
  exit 1
fi
log "Running save-signet-datadir-backup.sh..."
if ! ./save-signet-datadir-backup.sh >> "$LOG_FILE" 2>&1; then
  log "ERROR: save-signet-datadir-backup.sh failed"
  exit 1
fi
log "  signet datadir backup OK"

# 2. Run mining wallet export
if [ ! -x "${PROJECT_DIR}/export-mining-wallet.sh" ]; then
  log "ERROR: export-mining-wallet.sh not executable"
  exit 1
fi
log "Running export-mining-wallet.sh..."
if ! ./export-mining-wallet.sh >> "$LOG_FILE" 2>&1; then
  log "ERROR: export-mining-wallet.sh failed"
  exit 1
fi
log "  mining wallet export OK"

# 3. Clone or pull backup repo
if [ -d "$BACKUP_GIT_WORKSPACE/.git" ]; then
  log "Pulling backup repo..."
  (cd "$BACKUP_GIT_WORKSPACE" && git pull) >> "$LOG_FILE" 2>&1 || {
    log "WARN: git pull failed, continuing with local state"
  }
else
  log "Cloning backup repo..."
  mkdir -p "$(dirname "$BACKUP_GIT_WORKSPACE")"
  if ! git clone "$BACKUP_REPO_URL" "$BACKUP_GIT_WORKSPACE" >> "$LOG_FILE" 2>&1; then
    log "ERROR: git clone failed. Create repo at $BACKUP_REPO_URL first."
    exit 1
  fi
fi

mkdir -p "${BACKUP_GIT_WORKSPACE}/${SIGNET_SUBDIR}"
mkdir -p "${BACKUP_GIT_WORKSPACE}/${WALLET_SUBDIR}"

# 4. Copy latest signet-datadir backup (use real file, not symlink, for timestamped filename)
LATEST_SIGNET=$(readlink -f "$BACKUP_DIR/signet-datadir-latest.tar.gz" 2>/dev/null)
if [ -z "$LATEST_SIGNET" ] || [ ! -f "$LATEST_SIGNET" ]; then
  log "ERROR: no signet-datadir backup found in $BACKUP_DIR"
  exit 1
fi
cp "$LATEST_SIGNET" "${BACKUP_GIT_WORKSPACE}/${SIGNET_SUBDIR}/$(basename "$LATEST_SIGNET")"
log "  Copied $(basename "$LATEST_SIGNET") to ${SIGNET_SUBDIR}/"

# 5. Copy latest mining wallet export (use real file, not symlink, for timestamped filename)
LATEST_WALLET=$(readlink -f "$BACKUP_DIR/mining-wallet-export-latest.json" 2>/dev/null)
if [ -z "$LATEST_WALLET" ] || [ ! -f "$LATEST_WALLET" ]; then
  log "ERROR: no mining-wallet export found in $BACKUP_DIR"
  exit 1
fi
cp "$LATEST_WALLET" "${BACKUP_GIT_WORKSPACE}/${WALLET_SUBDIR}/$(basename "$LATEST_WALLET")"
log "  Copied $(basename "$LATEST_WALLET") to ${WALLET_SUBDIR}/"

# 6. Remove any *-latest* files from backup repo (only timestamped versions belong)
rm -f "${BACKUP_GIT_WORKSPACE}/${SIGNET_SUBDIR}/signet-datadir-latest.tar.gz"
rm -f "${BACKUP_GIT_WORKSPACE}/${WALLET_SUBDIR}/mining-wallet-export-latest.json"

# 7. Prune signet-datadir: keep only KEEP_VERSIONS most recent (by filename timestamp)
cd "${BACKUP_GIT_WORKSPACE}/${SIGNET_SUBDIR}"
while [ "$(ls -1 signet-datadir-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]-*.tar.gz 2>/dev/null | wc -l)" -gt "$KEEP_VERSIONS" ]; do
  OLDEST=$(ls signet-datadir-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]-*.tar.gz 2>/dev/null | sort | head -1)
  rm -f "$OLDEST"
  log "  Pruned signet: $OLDEST"
done

# 8. Prune mining-wallet: keep only KEEP_VERSIONS most recent (by filename timestamp)
cd "${BACKUP_GIT_WORKSPACE}/${WALLET_SUBDIR}"
while [ "$(ls -1 mining-wallet-export-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]-*.json 2>/dev/null | wc -l)" -gt "$KEEP_VERSIONS" ]; do
  OLDEST=$(ls mining-wallet-export-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]-*.json 2>/dev/null | sort | head -1)
  rm -f "$OLDEST"
  log "  Pruned wallet: $OLDEST"
done

# 9. Commit and push
cd "$BACKUP_GIT_WORKSPACE"
if git status --porcelain | grep -q .; then
  git add "${SIGNET_SUBDIR}/" "${WALLET_SUBDIR}/"
  git commit -m "backup: signet datadir and mining wallet $(date -Iseconds)" >> "$LOG_FILE" 2>&1
  log "Pushing to $BACKUP_REPO_URL..."
  if git push >> "$LOG_FILE" 2>&1; then
    log "  Push OK"
  else
    log "ERROR: git push failed"
    exit 1
  fi
else
  log "No changes to commit (backups identical)"
fi

log "=== Done ==="
tail -n 150 "$LOG_FILE" > "$LOG_FILE.tmp" && mv "$LOG_FILE.tmp" "$LOG_FILE"