#!/bin/bash
#
# Export the mining wallet (custom_signet) in a re-importable format.
# Contains: PRIVKEY, SIGNETCHALLENGE, wallet name, descriptors with private keys,
# and chain info — everything needed to recover funds on this Signet chain.
#
# Output: backups/mining-wallet-export-YYYYMMDD-HHMMSS.json
# Symlink: backups/mining-wallet-export-latest.json (ready to download)
#
# Re-import: ./import-mining-wallet.sh backups/mining-wallet-export-latest.json
#
# Author: 4NK Team
# Date: 2026-02-02

set -e

CONTAINER_NAME="bitcoin-signet-instance"
WALLET_NAME="custom_signet"
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
cd "$SCRIPT_DIR"
BACKUP_DIR="${1:-$SCRIPT_DIR/backups}"
mkdir -p "$BACKUP_DIR"
TIMESTAMP=$(date +%Y%m%d-%H%M%S)
OUTPUT_FILE="$BACKUP_DIR/mining-wallet-export-$TIMESTAMP.json"

if ! docker ps --format "{{.Names}}" | grep -q "^${CONTAINER_NAME}$"; then
    echo "Error: Container ${CONTAINER_NAME} is not running"
    exit 1
fi

DATADIR=$(docker exec "$CONTAINER_NAME" printenv BITCOIN_DIR 2>/dev/null || echo "/root/.bitcoin")

echo "=== Export mining wallet (re-importable) ==="
echo "Container: $CONTAINER_NAME"
echo "Wallet: $WALLET_NAME"
echo "Output: $OUTPUT_FILE"
echo ""

PRIVKEY=$(sudo docker exec "$CONTAINER_NAME" cat "$DATADIR/PRIVKEY.txt" 2>/dev/null || echo "")
SIGNETCHALLENGE=$(sudo docker exec "$CONTAINER_NAME" cat "$DATADIR/SIGNETCHALLENGE.txt" 2>/dev/null || echo "")
BLOCKCHAIN_INFO=$(sudo docker exec "$CONTAINER_NAME" bitcoin-cli -datadir="$DATADIR" getblockchaininfo 2>/dev/null || echo "{}")
DESCRIPTORS_RAW=$(sudo docker exec "$CONTAINER_NAME" bitcoin-cli -datadir="$DATADIR" -rpcwallet="$WALLET_NAME" listdescriptors true 2>/dev/null || echo "{\"descriptors\":[]}")

# Build importdescriptors-compatible array: each item {desc, timestamp, internal}
DESCRIPTORS_IMPORT=$(echo "$DESCRIPTORS_RAW" | jq -c '
  .descriptors
  | map(select(.desc != null))
  | map({
      desc: .desc,
      timestamp: (if .timestamp != null then .timestamp else 0 end),
      internal: (if .internal == true then true elif .internal == false then false else false end)
    })
')

# Single JSON document for re-import and recovery on this chain
jq -n \
  --arg chain "signet" \
  --arg signet_challenge "${SIGNETCHALLENGE}" \
  --arg privkey "${PRIVKEY}" \
  --arg wallet_name "${WALLET_NAME}" \
  --argjson descriptors "${DESCRIPTORS_IMPORT}" \
  --argjson blockchain_info "${BLOCKCHAIN_INFO}" \
  '{
    export_version: "1.0",
    export_date: (now | strftime("%Y-%m-%dT%H:%M:%SZ")),
    chain: $chain,
    signet_challenge: $signet_challenge,
    privkey: $privkey,
    wallet_name: $wallet_name,
    descriptors: $descriptors,
    blockchain_at_export: $blockchain_info,
    reimport: "Run: ./import-mining-wallet.sh <this-file.json> on a node with the same SIGNETCHALLENGE"
  }' > "$OUTPUT_FILE"

ln -sf "$(basename "$OUTPUT_FILE")" "$BACKUP_DIR/mining-wallet-export-latest.json"

echo "Export saved: $OUTPUT_FILE"
echo "Latest symlink: $BACKUP_DIR/mining-wallet-export-latest.json"
echo "Size: $(du -h "$OUTPUT_FILE" | cut -f1)"
echo ""
echo "To re-import and recover funds on this chain:"
echo "  ./import-mining-wallet.sh $OUTPUT_FILE"
echo "  # or: ./import-mining-wallet.sh $BACKUP_DIR/mining-wallet-export-latest.json"
echo ""
echo "WARNING: This file contains private keys. Keep it secure and encrypted."
echo ""