#!/usr/bin/env bash
# Clear selected Besu blockchain databases (NUCLEAR OPTION)
# This will require full re-sync from genesis.
# Usage:
#   ./clear-blockchain-database.sh --vmid 2101
#   ./clear-blockchain-database.sh --apply --vmid 2101

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
source "${PROJECT_ROOT}/scripts/lib/load-project-env.sh"

# Colors
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m'

log_info() { echo -e "${BLUE}[INFO]${NC} $1"; }
log_success() { echo -e "${GREEN}[✓]${NC} $1"; }
log_warn() { echo -e "${YELLOW}[WARN]${NC} $1"; }
log_error() { echo -e "${RED}[ERROR]${NC} $1"; }

# Check if pct is available
if ! command -v pct &>/dev/null; then
    log_error "This script must be run on the Proxmox host (pct command not found)"
    exit 1
fi

APPLY=false
TARGET_VMIDS=()

usage() {
    cat <<'EOF'
Usage: ./clear-blockchain-database.sh --vmid <N> [--vmid <N> ...] [--apply]

Options:
  --vmid <N>   Required. Limit destructive action to one or more VMIDs.
  --apply      Perform deletion. Without this flag, the script prints the target VMIDs and exits.
EOF
}

while [[ $# -gt 0 ]]; do
    case "$1" in
        --vmid)
            [[ $# -ge 2 ]] || { usage >&2; exit 2; }
            TARGET_VMIDS+=("$2")
            shift 2
            ;;
        --apply)
            APPLY=true
            shift
            ;;
        -h|--help)
            usage
            exit 0
            ;;
        *)
            echo "Unknown argument: $1" >&2
            usage >&2
            exit 2
            ;;
    esac
done

[[ ${#TARGET_VMIDS[@]} -gt 0 ]] || { log_error "At least one --vmid is required for this destructive script."; usage >&2; exit 2; }

echo "========================================="
echo "Clear Entire Blockchain Database"
echo "========================================="
echo ""
log_error "⚠️  ⚠️  ⚠️  CRITICAL WARNING ⚠️  ⚠️  ⚠️"
echo ""
log_error "This will:"
log_error "  1. DELETE the entire blockchain database"
log_error "  2. DELETE all transaction pools"
log_error "  3. DELETE all caches"
log_error "  4. Require FULL RE-SYNC from genesis"
log_error "  5. Take SIGNIFICANT TIME to re-sync"
echo ""
log_warn "This is a NUCLEAR OPTION - use only if absolutely necessary"
echo ""
declare -A SERVICE_BY_VMID
for vmid in 1000 1001 1002 1003 1004; do SERVICE_BY_VMID[$vmid]="besu-validator.service"; done
for vmid in 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510; do SERVICE_BY_VMID[$vmid]="besu-sentry.service"; done
for vmid in 2101 2102 2103 2201 2301 2303 2304 2305 2306 2307 2308 2400 2401 2402 2403 2420 2430 2440 2460 2470 2480; do SERVICE_BY_VMID[$vmid]="besu-rpc.service"; done

if ! $APPLY; then
    log_warn "Dry-run only. Target VMIDs:"
    for vmid in "${TARGET_VMIDS[@]}"; do
        log_info "  VMID $vmid (host $(get_host_for_vmid "$vmid")) service ${SERVICE_BY_VMID[$vmid]:-unknown}"
    done
    log_info "Re-run with --apply to proceed."
    exit 0
fi

read -p "Type 'DELETE DATABASE' to confirm: " CONFIRM
if [ "$CONFIRM" != "DELETE DATABASE" ]; then
    log_info "Aborted"
    exit 0
fi

log_info "Stopping selected Besu nodes..."
for vmid in "${TARGET_VMIDS[@]}"; do
    service="${SERVICE_BY_VMID[$vmid]:-besu.service}"
    if pct status "$vmid" 2>/dev/null | grep -q "running"; then
        log_info "Stopping VMID $vmid ($service)..."
        pct exec "$vmid" -- systemctl stop "$service" 2>/dev/null || pct exec "$vmid" -- systemctl stop besu.service 2>/dev/null || true
    fi
done

sleep 5

log_info "Clearing selected blockchain databases..."
for vmid in "${TARGET_VMIDS[@]}"; do
    if pct status "$vmid" 2>/dev/null | grep -q "running"; then
        log_info "Clearing VMID $vmid..."
        
        # Clear database
        pct exec "$vmid" -- rm -rf /data/besu/database/* 2>/dev/null || true
        
        # Clear caches
        pct exec "$vmid" -- rm -rf /data/besu/caches/* 2>/dev/null || true
        
        # Clear any transaction pool files
        pct exec "$vmid" -- find /data/besu -type f -name "*pool*" -delete 2>/dev/null || true
        pct exec "$vmid" -- find /data/besu -type d -name "*pool*" -exec rm -rf {} \; 2>/dev/null || true
        
        log_success "✓ VMID $vmid cleared"
    fi
done

log_info "Starting selected Besu nodes..."
for vmid in "${TARGET_VMIDS[@]}"; do
    service="${SERVICE_BY_VMID[$vmid]:-besu.service}"
    if pct status "$vmid" 2>/dev/null | grep -q "running"; then
        log_info "Starting VMID $vmid ($service)..."
        pct exec "$vmid" -- systemctl start "$service" 2>/dev/null || pct exec "$vmid" -- systemctl start besu.service 2>/dev/null || true
    fi
done

log_info "Waiting 30 seconds for services to start..."
sleep 30

log_success "========================================="
log_success "Blockchain Database Cleared!"
log_success "========================================="
log_info ""
log_warn "⚠️  Nodes will now re-sync from genesis"
log_warn "⚠️  This may take significant time"
log_info ""
log_info "Next steps:"
log_info "  1. Wait for nodes to re-sync (monitor block numbers)"
log_info "  2. Once synced, run: ./scripts/configure-ethereum-mainnet-final.sh"
log_info ""