#!/bin/sh
# SPDX-License-Identifier: Apache-2.0
# SecuBox Security Threats Dashboard RPCD backend
# Copyright (C) 2026 CyberMind.fr - Gandalf
#
# Integrates netifyd DPI security risks with CrowdSec threat intelligence
# for comprehensive network threat monitoring and automated blocking

. /lib/functions.sh
. /usr/share/libubox/jshn.sh

HISTORY_FILE="/tmp/secubox-threats-history.json"
CSCLI="/usr/bin/cscli"
SECCUBOX_LOG="/usr/sbin/secubox-log"

secubox_log() {
	[ -x "$SECCUBOX_LOG" ] || return
	"$SECCUBOX_LOG" --tag "security-threats" --message "$1" >/dev/null 2>&1
}

# Initialize storage
init_storage() {
	[ ! -f "$HISTORY_FILE" ] && echo '[]' > "$HISTORY_FILE"
}

# ==============================================================================
# DATA COLLECTION
# ==============================================================================

# Get netifyd flows (socket first, fallback to file)
get_netifyd_flows() {
	if [ -S /var/run/netifyd/netifyd.sock ]; then
		echo "status" | nc -U /var/run/netifyd/netifyd.sock 2>/dev/null
	elif [ -f /var/run/netifyd/status.json ]; then
		cat /var/run/netifyd/status.json
	else
		echo '{}'
	fi
}

# Filter flows with security risks
filter_risky_flows() {
	local flows="$1"
	# Extract flows with risks[] array (length > 0)
	echo "$flows" | jq -c '.flows[]? | select(.risks != null and (.risks | length) > 0)' 2>/dev/null
}

# Get CrowdSec decisions (active bans)
get_crowdsec_decisions() {
	[ ! -x "$CSCLI" ] && echo '[]' && return
	$CSCLI decisions list -o json 2>/dev/null || echo '[]'
}

# Get CrowdSec alerts (recent detections)
get_crowdsec_alerts() {
	[ ! -x "$CSCLI" ] && echo '[]' && return
	$CSCLI alerts list -o json --limit 100 2>/dev/null || echo '[]'
}

# ==============================================================================
# CLASSIFICATION
# ==============================================================================

# Classify netifyd risk by category
classify_netifyd_risk() {
	local risk_name="$1"

	# Map ND_RISK_* to categories
	case "$risk_name" in
		*MALICIOUS_JA3*|*SUSPICIOUS_DGA*|*SUSPICIOUS_ENTROPY*|*POSSIBLE_EXPLOIT*|*PERIODIC_FLOW*)
			echo "malware";;
		*SQL_INJECTION*|*XSS*|*RCE_INJECTION*|*HTTP_SUSPICIOUS*)
			echo "web_attack";;
		*DNS_FRAGMENTED*|*DNS_LARGE_PACKET*|*DNS_SUSPICIOUS*|*RISKY_ASN*|*RISKY_DOMAIN*|*UNIDIRECTIONAL*|*MALFORMED_PACKET*)
			echo "anomaly";;
		*BitTorrent*|*Mining*|*Tor*|*PROXY*|*SOCKS*)
			echo "protocol";;
		*TLS_*|*CERTIFICATE_*)
			echo "tls_issue";;
		*)
			echo "other";;
	esac
}

# Calculate risk score (0-100)
calculate_risk_score() {
	local risk_count="$1"
	local has_crowdsec="$2"
	local risk_types="$3"  # comma-separated

	local score=$((risk_count * 10))  # Base: 10 per risk
	[ "$score" -gt 50 ] && score=50    # Cap base at 50

	# Severity weights
	echo "$risk_types" | grep -q "MALICIOUS_JA3\|SUSPICIOUS_DGA\|POSSIBLE_EXPLOIT" && score=$((score + 20))
	echo "$risk_types" | grep -q "SQL_INJECTION\|XSS\|RCE" && score=$((score + 15))
	echo "$risk_types" | grep -q "RISKY_ASN\|RISKY_DOMAIN" && score=$((score + 10))
	echo "$risk_types" | grep -q "BitTorrent\|Mining\|Tor" && score=$((score + 5))

	# CrowdSec correlation bonus
	[ "$has_crowdsec" = "1" ] && score=$((score + 30))

	# Cap at 100
	[ "$score" -gt 100 ] && score=100
	echo "$score"
}

# Determine severity level
get_threat_severity() {
	local score="$1"
	if [ "$score" -ge 80 ]; then
		echo "critical"
	elif [ "$score" -ge 60 ]; then
		echo "high"
	elif [ "$score" -ge 40 ]; then
		echo "medium"
	else
		echo "low"
	fi
}

# ==============================================================================
# CORRELATION ENGINE
# ==============================================================================

# Correlate netifyd risks with CrowdSec data
correlate_threats() {
	local netifyd_flows="$1"
	local crowdsec_decisions="$2"
	local crowdsec_alerts="$3"

	# Create lookup tables with jq
	local decisions_by_ip=$(echo "$crowdsec_decisions" | jq -c 'INDEX(.value)' 2>/dev/null || echo '{}')
	local alerts_by_ip=$(echo "$crowdsec_alerts" | jq -c 'group_by(.source.ip) | map({(.[0].source.ip): .}) | add // {}' 2>/dev/null || echo '{}')

	# Process each risky flow
	echo "$netifyd_flows" | while read -r flow; do
		[ -z "$flow" ] && continue

		local ip=$(echo "$flow" | jq -r '.src_ip // "unknown"')
		[ "$ip" = "unknown" ] && continue

		local mac=$(echo "$flow" | jq -r '.src_mac // "N/A"')
		local risks=$(echo "$flow" | jq -r '.risks | map(tostring) | join(",")' 2>/dev/null || echo "")
		local risk_count=$(echo "$flow" | jq '.risks | length' 2>/dev/null || echo 0)

		# Lookup CrowdSec data
		local decision=$(echo "$decisions_by_ip" | jq -c ".[\"$ip\"] // null")
		local has_decision=$([[ "$decision" != "null" ]] && echo 1 || echo 0)
		local alert=$(echo "$alerts_by_ip" | jq -c ".[\"$ip\"] // null")

		# Calculate metrics
		local risk_score=$(calculate_risk_score "$risk_count" "$has_decision" "$risks")
		local severity=$(get_threat_severity "$risk_score")
		local first_risk=$(echo "$risks" | cut -d, -f1)
		local category=$(classify_netifyd_risk "$first_risk")

		# Build unified threat JSON
		jq -n \
			--arg ip "$ip" \
			--arg mac "$mac" \
			--arg timestamp "$(date -Iseconds)" \
			--argjson score "$risk_score" \
			--arg severity "$severity" \
			--arg category "$category" \
			--argjson netifyd "$(echo "$flow" | jq '{
				application: .detected_application // "unknown",
				protocol: .detected_protocol // "unknown",
				risks: [.risks[] | tostring],
				risk_count: (.risks | length),
				bytes: .total_bytes // 0,
				packets: .total_packets // 0
			}')" \
			--argjson crowdsec "$(jq -n \
				--argjson decision "$decision" \
				--argjson alert "$alert" \
				'{
					has_decision: ($decision != null),
					decision: $decision,
					has_alert: ($alert != null),
					alert_count: (if $alert != null then ($alert | length) else 0 end),
					scenarios: (if $alert != null then ($alert | map(.scenario) | join(",")) else "" end)
				}')" \
			'{
				ip: $ip,
				mac: $mac,
				timestamp: $timestamp,
				risk_score: $score,
				severity: $severity,
				category: $category,
				netifyd: $netifyd,
				crowdsec: $crowdsec
			}' 2>/dev/null
	done
}

# ==============================================================================
# AUTO-BLOCKING
# ==============================================================================

# Execute block via CrowdSec
execute_block() {
	local ip="$1"
	local duration="$2"
	local reason="$3"

	[ ! -x "$CSCLI" ] && return 1

	# Call cscli to add decision
	if $CSCLI decisions add --ip "$ip" --duration "$duration" --reason "$reason" >/dev/null 2>&1; then
		secubox_log "Auto-blocked $ip for $duration ($reason)"
		return 0
	else
		return 1
	fi
}

# Check single rule match
check_rule_match() {
	local section="$1"
	local threat_category="$2"
	local threat_risks="$3"
	local threat_score="$4"
	local threat_ip="$5"

	local enabled=$(uci -q get "secubox_security_threats.${section}.enabled")
	[ "$enabled" != "1" ] && return 1

	local rule_types=$(uci -q get "secubox_security_threats.${section}.threat_types")
	echo "$rule_types" | grep -qw "$threat_category" || return 1

	local threshold=$(uci -q get "secubox_security_threats.${section}.threshold" 2>/dev/null || echo 1)
	[ "$threat_score" -lt "$threshold" ] && return 1

	# Rule matched - execute block
	local duration=$(uci -q get "secubox_security_threats.${section}.duration" || echo "4h")
	local name=$(uci -q get "secubox_security_threats.${section}.name" || echo "Security threat")

	execute_block "$threat_ip" "$duration" "Auto-blocked: $name"
	return $?
}

# Check if threat should be auto-blocked
check_block_rules() {
	local threat="$1"

	local ip=$(echo "$threat" | jq -r '.ip')
	local category=$(echo "$threat" | jq -r '.category')
	local score=$(echo "$threat" | jq -r '.risk_score')
	local risks=$(echo "$threat" | jq -r '.netifyd.risks | join(",")')

	# Check whitelist first
	local whitelist_section="whitelist_${ip//./_}"
	uci -q get "secubox_security_threats.${whitelist_section}" >/dev/null 2>&1 && return 1

	# Check if auto-blocking is enabled globally
	local auto_block_enabled=$(uci -q get secubox_security_threats.global.auto_block_enabled 2>/dev/null || echo 1)
	[ "$auto_block_enabled" != "1" ] && return 1

	# Iterate block rules from UCI
	config_load secubox_security_threats
	config_foreach check_rule_match block_rule "$category" "$risks" "$score" "$ip"
}

# ==============================================================================
# SECURITY STATS (Quick Overview)
# ==============================================================================

# Get overall security statistics from all sources
get_security_stats() {
	local wan_drops=0
	local fw_rejects=0
	local cs_bans=0
	local cs_alerts_24h=0
	local haproxy_conns=0
	local invalid_conns=0

	# WAN dropped packets (from kernel stats)
	if [ -f /sys/class/net/br-wan/statistics/rx_dropped ]; then
		wan_drops=$(cat /sys/class/net/br-wan/statistics/rx_dropped 2>/dev/null)
	elif [ -f /sys/class/net/eth1/statistics/rx_dropped ]; then
		wan_drops=$(cat /sys/class/net/eth1/statistics/rx_dropped 2>/dev/null)
	fi
	wan_drops=${wan_drops:-0}

	# Firewall rejects from logs (last 24h)
	fw_rejects=$(logread 2>/dev/null | grep -c "reject\|drop" || echo 0)
	fw_rejects=$(echo "$fw_rejects" | tr -d '\n')
	fw_rejects=${fw_rejects:-0}

	# CrowdSec active bans
	if [ -x "$CSCLI" ]; then
		cs_bans=$($CSCLI decisions list -o json 2>/dev/null | grep -c '"id":' || echo 0)
		cs_bans=$(echo "$cs_bans" | tr -d '\n')
		cs_bans=${cs_bans:-0}

		# CrowdSec alerts in last 24h
		cs_alerts_24h=$($CSCLI alerts list -o json --since 24h 2>/dev/null | grep -c '"id":' || echo 0)
		cs_alerts_24h=$(echo "$cs_alerts_24h" | tr -d '\n')
		cs_alerts_24h=${cs_alerts_24h:-0}
	fi

	# Invalid connections (conntrack)
	if [ -f /proc/net/nf_conntrack ]; then
		invalid_conns=$(grep -c "INVALID\|UNREPLIED" /proc/net/nf_conntrack 2>/dev/null || echo 0)
	fi
	invalid_conns=$(echo "$invalid_conns" | tr -d '\n')
	invalid_conns=${invalid_conns:-0}

	# HAProxy connections (if running in LXC)
	if lxc-info -n haproxy -s 2>/dev/null | grep -q "RUNNING"; then
		haproxy_conns=$(lxc-attach -n haproxy -- sh -c 'echo "show stat" | socat stdio /var/run/haproxy/admin.sock 2>/dev/null | tail -n+2 | awk -F, "{sum+=\$8} END {print sum}"' 2>/dev/null || echo 0)
	fi
	haproxy_conns=$(echo "$haproxy_conns" | tr -d '\n')
	haproxy_conns=${haproxy_conns:-0}

	# Output JSON
	cat << EOF
{
	"wan_dropped": $wan_drops,
	"firewall_rejects": $fw_rejects,
	"crowdsec_bans": $cs_bans,
	"crowdsec_alerts_24h": $cs_alerts_24h,
	"invalid_connections": $invalid_conns,
	"haproxy_connections": $haproxy_conns,
	"timestamp": "$(date -Iseconds)"
}
EOF
}

# ==============================================================================
# STATISTICS
# ==============================================================================

# Get stats by type (category)
get_stats_by_type() {
	local threats="$1"

	echo "$threats" | jq -s '{
		malware: [.[] | select(.category == "malware")] | length,
		web_attack: [.[] | select(.category == "web_attack")] | length,
		anomaly: [.[] | select(.category == "anomaly")] | length,
		protocol: [.[] | select(.category == "protocol")] | length,
		tls_issue: [.[] | select(.category == "tls_issue")] | length,
		other: [.[] | select(.category == "other")] | length
	}' 2>/dev/null
}

# Get stats by host (IP)
get_stats_by_host() {
	local threats="$1"

	echo "$threats" | jq -s 'group_by(.ip) | map({
		ip: .[0].ip,
		mac: .[0].mac,
		threat_count: length,
		avg_risk_score: (map(.risk_score) | add / length | floor),
		highest_severity: (map(.severity) | sort | reverse | .[0]),
		first_seen: (map(.timestamp) | sort | .[0]),
		last_seen: (map(.timestamp) | sort | reverse | .[0]),
		categories: (map(.category) | unique | join(","))
	})' 2>/dev/null
}

# ==============================================================================
# UBUS INTERFACE
# ==============================================================================

case "$1" in
	list)
		# List available methods
		json_init
		json_add_object "get_security_stats"
		json_close_object
		json_add_object "status"
		json_close_object
		json_add_object "get_active_threats"
		json_close_object
		json_add_object "get_threat_history"
			json_add_string "hours" "int"
		json_close_object
		json_add_object "get_stats_by_type"
		json_close_object
		json_add_object "get_stats_by_host"
		json_close_object
		json_add_object "get_blocked_ips"
		json_close_object
		json_add_object "block_threat"
			json_add_string "ip" "string"
			json_add_string "duration" "string"
			json_add_string "reason" "string"
		json_close_object
		json_add_object "whitelist_host"
			json_add_string "ip" "string"
			json_add_string "reason" "string"
		json_close_object
		json_add_object "remove_whitelist"
			json_add_string "ip" "string"
		json_close_object
		json_dump
		;;

	call)
		case "$2" in
			get_security_stats)
				get_security_stats
				;;

			status)
				json_init
				json_add_boolean "enabled" 1
				json_add_string "module" "secubox-security-threats"
				json_add_string "version" "1.0.0"
				json_add_boolean "netifyd_running" $(pgrep netifyd >/dev/null && echo 1 || echo 0)
				json_add_boolean "crowdsec_running" $(pgrep crowdsec >/dev/null && echo 1 || echo 0)
				json_add_boolean "cscli_available" $([ -x "$CSCLI" ] && echo 1 || echo 0)
				json_dump
				;;

			get_active_threats)
				# Main correlation workflow
				local netifyd_data=$(get_netifyd_flows)
				local risky_flows=$(filter_risky_flows "$netifyd_data")

				# Only fetch CrowdSec data if available
				local decisions='[]'
				local alerts='[]'
				if [ -x "$CSCLI" ]; then
					decisions=$(get_crowdsec_decisions)
					alerts=$(get_crowdsec_alerts)
				fi

				# Correlate threats
				local threats=$(correlate_threats "$risky_flows" "$decisions" "$alerts")

				# Check auto-block rules for each threat
				if [ -n "$threats" ]; then
					echo "$threats" | while read -r threat; do
						[ -z "$threat" ] && continue
						check_block_rules "$threat" >/dev/null 2>&1 || true
					done
				fi

				# Output as JSON array
				json_init
				json_add_array "threats"
				if [ -n "$threats" ]; then
					echo "$threats" | jq -s 'sort_by(.risk_score) | reverse' | jq -c '.[]' | while read -r threat; do
						echo "$threat"
					done
				fi
				json_close_array
				json_dump
				;;

			get_threat_history)
				read -r input
				json_load "$input"
				json_get_var hours hours
				hours=${hours:-24}

				init_storage

				# Filter history by time
				local cutoff_time=$(date -d "$hours hours ago" -Iseconds 2>/dev/null || date -Iseconds)

				json_init
				json_add_array "threats"
				if [ -f "$HISTORY_FILE" ]; then
					jq -c --arg cutoff "$cutoff_time" '.[] | select(.timestamp >= $cutoff)' "$HISTORY_FILE" 2>/dev/null | while read -r threat; do
						echo "$threat"
					done
				fi
				json_close_array
				json_dump
				;;

			get_stats_by_type)
				local netifyd_data=$(get_netifyd_flows)
				local risky_flows=$(filter_risky_flows "$netifyd_data")
				local decisions=$(get_crowdsec_decisions)
				local alerts=$(get_crowdsec_alerts)
				local threats=$(correlate_threats "$risky_flows" "$decisions" "$alerts")

				local stats=$(get_stats_by_type "$threats")

				echo "$stats"
				;;

			get_stats_by_host)
				local netifyd_data=$(get_netifyd_flows)
				local risky_flows=$(filter_risky_flows "$netifyd_data")
				local decisions=$(get_crowdsec_decisions)
				local alerts=$(get_crowdsec_alerts)
				local threats=$(correlate_threats "$risky_flows" "$decisions" "$alerts")

				json_init
				json_add_array "hosts"
				if [ -n "$threats" ]; then
					get_stats_by_host "$threats" | jq -c '.[]' | while read -r host; do
						echo "$host"
					done
				fi
				json_close_array
				json_dump
				;;

			get_blocked_ips)
				if [ -x "$CSCLI" ]; then
					local decisions=$(get_crowdsec_decisions)
					echo "{\"blocked\":$decisions}"
				else
					echo '{"blocked":[]}'
				fi
				;;

			block_threat)
				read -r input
				json_load "$input"
				json_get_var ip ip
				json_get_var duration duration
				json_get_var reason reason

				if [ -z "$ip" ]; then
					json_init
					json_add_boolean "success" 0
					json_add_string "error" "IP address required"
					json_dump
					exit 0
				fi

				duration=${duration:-4h}
				reason=${reason:-"Manual block from Security Threats Dashboard"}

				if execute_block "$ip" "$duration" "$reason"; then
					json_init
					json_add_boolean "success" 1
					json_add_string "message" "IP $ip blocked for $duration"
					json_dump
				else
					json_init
					json_add_boolean "success" 0
					json_add_string "error" "Failed to block IP (check if CrowdSec is running)"
					json_dump
				fi
				;;

			whitelist_host)
				read -r input
				json_load "$input"
				json_get_var ip ip
				json_get_var reason reason

				if [ -z "$ip" ]; then
					json_init
					json_add_boolean "success" 0
					json_add_string "error" "IP address required"
					json_dump
					exit 0
				fi

				reason=${reason:-"Whitelisted from Security Threats Dashboard"}
				local section="whitelist_${ip//./_}"

				uci set "secubox_security_threats.${section}=whitelist"
				uci set "secubox_security_threats.${section}.ip=$ip"
				uci set "secubox_security_threats.${section}.reason=$reason"
				uci set "secubox_security_threats.${section}.added_at=$(date -Iseconds)"
				uci commit secubox_security_threats

				json_init
				json_add_boolean "success" 1
				json_add_string "message" "IP $ip added to whitelist"
				json_dump
				;;

			remove_whitelist)
				read -r input
				json_load "$input"
				json_get_var ip ip

				if [ -z "$ip" ]; then
					json_init
					json_add_boolean "success" 0
					json_add_string "error" "IP address required"
					json_dump
					exit 0
				fi

				local section="whitelist_${ip//./_}"
				uci delete "secubox_security_threats.${section}" 2>/dev/null
				uci commit secubox_security_threats

				json_init
				json_add_boolean "success" 1
				json_add_string "message" "IP $ip removed from whitelist"
				json_dump
				;;

			*)
				json_init
				json_add_boolean "error" 1
				json_add_string "message" "Unknown method: $2"
				json_dump
				;;
		esac
		;;
esac