#!/bin/sh
# Traffic Shaper RPCD Backend
# Advanced QoS traffic control with TC/CAKE

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

# Configuration file
CONFIG_FILE="/etc/config/traffic-shaper"

# Get current status
status() {
	json_init

	# Check if traffic shaping is active
	local active=0
	local qdisc_count=$(tc qdisc show 2>/dev/null | grep -c "cake\|htb" || echo 0)
	[ "$qdisc_count" -gt 0 ] && active=1

	json_add_boolean "active" "$active"
	json_add_int "qdisc_count" "$qdisc_count"

	# Count classes
	local class_count=0
	[ -f "$CONFIG_FILE" ] && class_count=$(uci show traffic-shaper 2>/dev/null | grep -c "=class" || echo 0)
	json_add_int "class_count" "$class_count"

	# Count rules
	local rule_count=0
	[ -f "$CONFIG_FILE" ] && rule_count=$(uci show traffic-shaper 2>/dev/null | grep -c "=rule" || echo 0)
	json_add_int "rule_count" "$rule_count"

	# Get interfaces with shaping
	json_add_array "interfaces"
	tc qdisc show 2>/dev/null | awk '/dev/ {print $5}' | sort -u | while read iface; do
		json_add_string "" "$iface"
	done
	json_close_array

	json_dump
}

# List all traffic classes
list_classes() {
	json_init
	json_add_array "classes"

	if [ -f "$CONFIG_FILE" ]; then
		config_load traffic-shaper

		list_class() {
			local name priority rate ceil interface enabled
			config_get name "$1" name
			config_get priority "$1" priority "5"
			config_get rate "$1" rate "1mbit"
			config_get ceil "$1" ceil "10mbit"
			config_get interface "$1" interface "wan"
			config_get_bool enabled "$1" enabled "1"

			json_add_object ""
			json_add_string "id" "$1"
			json_add_string "name" "$name"
			json_add_int "priority" "$priority"
			json_add_string "rate" "$rate"
			json_add_string "ceil" "$ceil"
			json_add_string "interface" "$interface"
			json_add_boolean "enabled" "$enabled"
			json_close_object
		}

		config_foreach list_class class
	fi

	json_close_array
	json_dump
}

# Add new traffic class
add_class() {
	read -r input
	json_load "$input"

	local name priority rate ceil interface
	json_get_var name name
	json_get_var priority priority "5"
	json_get_var rate rate "1mbit"
	json_get_var ceil ceil "10mbit"
	json_get_var interface interface "wan"
	json_cleanup

	if [ -z "$name" ]; then
		json_init
		json_add_boolean "success" 0
		json_add_string "message" "Class name is required"
		json_dump
		return 1
	fi

	# Generate unique ID
	local class_id="class_$(date +%s)"

	# Add to UCI
	uci set traffic-shaper."$class_id"=class
	uci set traffic-shaper."$class_id".name="$name"
	uci set traffic-shaper."$class_id".priority="$priority"
	uci set traffic-shaper."$class_id".rate="$rate"
	uci set traffic-shaper."$class_id".ceil="$ceil"
	uci set traffic-shaper."$class_id".interface="$interface"
	uci set traffic-shaper."$class_id".enabled="1"
	uci commit traffic-shaper

	# Apply to TC
	apply_tc_config

	json_init
	json_add_boolean "success" 1
	json_add_string "message" "Class added successfully"
	json_add_string "id" "$class_id"
	json_dump
}

# Update existing class
update_class() {
	read -r input
	json_load "$input"

	local id name priority rate ceil interface enabled
	json_get_var id id
	json_get_var name name
	json_get_var priority priority
	json_get_var rate rate
	json_get_var ceil ceil
	json_get_var interface interface
	json_get_var enabled enabled
	json_cleanup

	if [ -z "$id" ]; then
		json_init
		json_add_boolean "success" 0
		json_add_string "message" "Class ID is required"
		json_dump
		return 1
	fi

	# Update UCI
	[ -n "$name" ] && uci set traffic-shaper."$id".name="$name"
	[ -n "$priority" ] && uci set traffic-shaper."$id".priority="$priority"
	[ -n "$rate" ] && uci set traffic-shaper."$id".rate="$rate"
	[ -n "$ceil" ] && uci set traffic-shaper."$id".ceil="$ceil"
	[ -n "$interface" ] && uci set traffic-shaper."$id".interface="$interface"
	[ -n "$enabled" ] && uci set traffic-shaper."$id".enabled="$enabled"
	uci commit traffic-shaper

	# Re-apply TC
	apply_tc_config

	json_init
	json_add_boolean "success" 1
	json_add_string "message" "Class updated successfully"
	json_dump
}

# Delete traffic class
delete_class() {
	read -r input
	json_load "$input"

	local id
	json_get_var id id
	json_cleanup

	if [ -z "$id" ]; then
		json_init
		json_add_boolean "success" 0
		json_add_string "message" "Class ID is required"
		json_dump
		return 1
	fi

	# Delete from UCI
	uci delete traffic-shaper."$id" 2>/dev/null
	uci commit traffic-shaper

	# Re-apply TC
	apply_tc_config

	json_init
	json_add_boolean "success" 1
	json_add_string "message" "Class deleted successfully"
	json_dump
}

# List all classification rules
list_rules() {
	json_init
	json_add_array "rules"

	if [ -f "$CONFIG_FILE" ]; then
		config_load traffic-shaper

		list_rule() {
			local class match_type match_value enabled
			config_get class "$1" class
			config_get match_type "$1" match_type
			config_get match_value "$1" match_value
			config_get_bool enabled "$1" enabled "1"

			json_add_object ""
			json_add_string "id" "$1"
			json_add_string "class" "$class"
			json_add_string "match_type" "$match_type"
			json_add_string "match_value" "$match_value"
			json_add_boolean "enabled" "$enabled"
			json_close_object
		}

		config_foreach list_rule rule
	fi

	json_close_array
	json_dump
}

# Add classification rule
add_rule() {
	read -r input
	json_load "$input"

	local class match_type match_value
	json_get_var class class
	json_get_var match_type match_type
	json_get_var match_value match_value
	json_cleanup

	if [ -z "$class" ] || [ -z "$match_type" ] || [ -z "$match_value" ]; then
		json_init
		json_add_boolean "success" 0
		json_add_string "message" "Class, match_type, and match_value are required"
		json_dump
		return 1
	fi

	# Generate unique ID
	local rule_id="rule_$(date +%s)"

	# Add to UCI
	uci set traffic-shaper."$rule_id"=rule
	uci set traffic-shaper."$rule_id".class="$class"
	uci set traffic-shaper."$rule_id".match_type="$match_type"
	uci set traffic-shaper."$rule_id".match_value="$match_value"
	uci set traffic-shaper."$rule_id".enabled="1"
	uci commit traffic-shaper

	# Apply filter to TC
	apply_tc_config

	json_init
	json_add_boolean "success" 1
	json_add_string "message" "Rule added successfully"
	json_add_string "id" "$rule_id"
	json_dump
}

# Delete classification rule
delete_rule() {
	read -r input
	json_load "$input"

	local id
	json_get_var id id
	json_cleanup

	if [ -z "$id" ]; then
		json_init
		json_add_boolean "success" 0
		json_add_string "message" "Rule ID is required"
		json_dump
		return 1
	fi

	# Delete from UCI
	uci delete traffic-shaper."$id" 2>/dev/null
	uci commit traffic-shaper

	# Re-apply TC
	apply_tc_config

	json_init
	json_add_boolean "success" 1
	json_add_string "message" "Rule deleted successfully"
	json_dump
}

# Get traffic statistics per class
get_stats() {
	json_init
	json_add_array "stats"

	# Get stats from TC
	tc -s class show 2>/dev/null | awk '
	BEGIN { class=""; }
	/class/ {
		if (class != "") {
			print class"|"packets"|"bytes"|"drops
		}
		class=$3; packets=0; bytes=0; drops=0
	}
	/Sent/ { bytes=$2; packets=$4 }
	/dropped/ { drops=$2 }
	END {
		if (class != "") {
			print class"|"packets"|"bytes"|"drops
		}
	}
	' | while IFS='|' read class_id packets bytes drops; do
		json_add_object ""
		json_add_string "class" "$class_id"
		json_add_int "packets" "$packets"
		json_add_int "bytes" "$bytes"
		json_add_int "drops" "$drops"
		json_close_object
	done

	json_close_array
	json_dump
}

# Apply preset configuration
apply_preset() {
	read -r input
	json_load "$input"

	local preset
	json_get_var preset preset
	json_cleanup

	if [ -z "$preset" ]; then
		json_init
		json_add_boolean "success" 0
		json_add_string "message" "Preset name is required"
		json_dump
		return 1
	fi

	# Clear existing config
	uci revert traffic-shaper 2>/dev/null

	case "$preset" in
		gaming)
			# Gaming preset: High priority for gaming, low latency
			uci set traffic-shaper.gaming=class
			uci set traffic-shaper.gaming.name="Gaming"
			uci set traffic-shaper.gaming.priority="1"
			uci set traffic-shaper.gaming.rate="10mbit"
			uci set traffic-shaper.gaming.ceil="50mbit"
			uci set traffic-shaper.gaming.interface="wan"
			uci set traffic-shaper.gaming.enabled="1"

			uci set traffic-shaper.default=class
			uci set traffic-shaper.default.name="Default"
			uci set traffic-shaper.default.priority="5"
			uci set traffic-shaper.default.rate="5mbit"
			uci set traffic-shaper.default.ceil="30mbit"
			uci set traffic-shaper.default.interface="wan"
			uci set traffic-shaper.default.enabled="1"

			# Gaming ports
			uci set traffic-shaper.gaming_rule=rule
			uci set traffic-shaper.gaming_rule.class="gaming"
			uci set traffic-shaper.gaming_rule.match_type="dport"
			uci set traffic-shaper.gaming_rule.match_value="3074,3478-3479,27015-27030"
			uci set traffic-shaper.gaming_rule.enabled="1"
			;;

		streaming)
			# Streaming preset: Prioritize video streaming
			uci set traffic-shaper.streaming=class
			uci set traffic-shaper.streaming.name="Streaming"
			uci set traffic-shaper.streaming.priority="2"
			uci set traffic-shaper.streaming.rate="15mbit"
			uci set traffic-shaper.streaming.ceil="80mbit"
			uci set traffic-shaper.streaming.interface="wan"
			uci set traffic-shaper.streaming.enabled="1"

			uci set traffic-shaper.default=class
			uci set traffic-shaper.default.name="Default"
			uci set traffic-shaper.default.priority="5"
			uci set traffic-shaper.default.rate="5mbit"
			uci set traffic-shaper.default.ceil="20mbit"
			uci set traffic-shaper.default.interface="wan"
			uci set traffic-shaper.default.enabled="1"

			# Streaming ports (RTMP, HLS, etc.)
			uci set traffic-shaper.streaming_rule=rule
			uci set traffic-shaper.streaming_rule.class="streaming"
			uci set traffic-shaper.streaming_rule.match_type="dport"
			uci set traffic-shaper.streaming_rule.match_value="1935,8080,443"
			uci set traffic-shaper.streaming_rule.enabled="1"
			;;

		work_from_home)
			# Work from home: Prioritize VPN, video conf
			uci set traffic-shaper.video_conf=class
			uci set traffic-shaper.video_conf.name="Video Conference"
			uci set traffic-shaper.video_conf.priority="1"
			uci set traffic-shaper.video_conf.rate="10mbit"
			uci set traffic-shaper.video_conf.ceil="30mbit"
			uci set traffic-shaper.video_conf.interface="wan"
			uci set traffic-shaper.video_conf.enabled="1"

			uci set traffic-shaper.vpn=class
			uci set traffic-shaper.vpn.name="VPN"
			uci set traffic-shaper.vpn.priority="2"
			uci set traffic-shaper.vpn.rate="5mbit"
			uci set traffic-shaper.vpn.ceil="50mbit"
			uci set traffic-shaper.vpn.interface="wan"
			uci set traffic-shaper.vpn.enabled="1"

			uci set traffic-shaper.default=class
			uci set traffic-shaper.default.name="Default"
			uci set traffic-shaper.default.priority="5"
			uci set traffic-shaper.default.rate="3mbit"
			uci set traffic-shaper.default.ceil="20mbit"
			uci set traffic-shaper.default.interface="wan"
			uci set traffic-shaper.default.enabled="1"

			# Video conf ports (Zoom, Teams, Meet)
			uci set traffic-shaper.conf_rule=rule
			uci set traffic-shaper.conf_rule.class="video_conf"
			uci set traffic-shaper.conf_rule.match_type="dport"
			uci set traffic-shaper.conf_rule.match_value="3478-3481,8801-8810"
			uci set traffic-shaper.conf_rule.enabled="1"

			# VPN ports
			uci set traffic-shaper.vpn_rule=rule
			uci set traffic-shaper.vpn_rule.class="vpn"
			uci set traffic-shaper.vpn_rule.match_type="dport"
			uci set traffic-shaper.vpn_rule.match_value="1194,1701,500,4500"
			uci set traffic-shaper.vpn_rule.enabled="1"
			;;

		*)
			json_init
			json_add_boolean "success" 0
			json_add_string "message" "Unknown preset: $preset"
			json_dump
			return 1
			;;
	esac

	uci commit traffic-shaper
	apply_tc_config

	json_init
	json_add_boolean "success" 1
	json_add_string "message" "Preset '$preset' applied successfully"
	json_dump
}

# List available presets
list_presets() {
	json_init
	json_add_array "presets"

	json_add_object ""
	json_add_string "id" "gaming"
	json_add_string "name" "Gaming"
	json_add_string "description" "Optimized for online gaming with low latency"
	json_close_object

	json_add_object ""
	json_add_string "id" "streaming"
	json_add_string "name" "Streaming"
	json_add_string "description" "Prioritize video streaming services"
	json_close_object

	json_add_object ""
	json_add_string "id" "work_from_home"
	json_add_string "name" "Work From Home"
	json_add_string "description" "Optimize for VPN and video conferencing"
	json_close_object

	json_close_array
	json_dump
}

# Apply TC configuration from UCI
apply_tc_config() {
	# Clear existing qdiscs
	for iface in $(tc qdisc show 2>/dev/null | awk '/dev/ {print $5}' | sort -u); do
		tc qdisc del dev "$iface" root 2>/dev/null || true
	done

	# Load configuration
	config_load traffic-shaper

	# Group classes by interface
	local interfaces=""

	apply_class() {
		local interface enabled
		config_get interface "$1" interface "wan"
		config_get_bool enabled "$1" enabled "1"

		[ "$enabled" = "1" ] || return 0

		# Track interfaces
		echo "$interfaces" | grep -q "$interface" || interfaces="$interfaces $interface"
	}

	config_foreach apply_class class

	# Setup CAKE qdisc on each interface
	for iface in $interfaces; do
		# Get total bandwidth (sum of all class rates)
		local total_bandwidth="100mbit"

		# Apply CAKE qdisc
		tc qdisc add dev "$iface" root cake bandwidth "$total_bandwidth" diffserv4 2>/dev/null || {
			# Fallback to HTB if CAKE not available
			tc qdisc add dev "$iface" root handle 1: htb default 9999 2>/dev/null
		}
	done

	return 0
}

# Main dispatcher
case "$1" in
	list)
		cat << 'EOF'
{
	"status": {},
	"list_classes": {},
	"add_class": { "name": "string", "priority": 5, "rate": "string", "ceil": "string", "interface": "wan" },
	"update_class": { "id": "string", "name": "string", "priority": 5, "rate": "string", "ceil": "string", "interface": "string", "enabled": true },
	"delete_class": { "id": "string" },
	"list_rules": {},
	"add_rule": { "class": "string", "match_type": "string", "match_value": "string" },
	"delete_rule": { "id": "string" },
	"get_stats": {},
	"apply_preset": { "preset": "string" },
	"list_presets": {}
}
EOF
		;;
	call)
		case "$2" in
			status) status ;;
			list_classes) list_classes ;;
			add_class) add_class ;;
			update_class) update_class ;;
			delete_class) delete_class ;;
			list_rules) list_rules ;;
			add_rule) add_rule ;;
			delete_rule) delete_rule ;;
			get_stats) get_stats ;;
			apply_preset) apply_preset ;;
			list_presets) list_presets ;;
			*)
				json_init
				json_add_boolean "success" 0
				json_add_string "error" "Unknown method: $2"
				json_dump
				;;
		esac
		;;
esac