package router

import (
	dm "github.com/xtls/xray-core/common/matcher/domain"
	"github.com/xtls/xray-core/common/matcher/geoip"
	"github.com/xtls/xray-core/common/net"
	"github.com/xtls/xray-core/features/outbound"
	"github.com/xtls/xray-core/features/routing"
)

type Rule struct {
	Tag       string
	Balancer  *Balancer
	Condition Condition
}

func (r *Rule) GetTag() (string, error) {
	if r.Balancer != nil {
		return r.Balancer.PickOutbound()
	}
	return r.Tag, nil
}

// Apply checks rule matching of current routing context.
func (r *Rule) Apply(ctx routing.Context) bool {
	return r.Condition.Apply(ctx)
}

func (rr *RoutingRule) BuildCondition() (Condition, error) {
	conds := NewConditionChan()

	if len(rr.Domain) > 0 {
		matcher, err := dm.NewDomainMatcher(rr.Domain)
		if err != nil {
			return nil, newError("failed to build domain condition").Base(err)
		}
		conds.Add(matcher)
	}

	if len(rr.UserEmail) > 0 {
		conds.Add(NewUserMatcher(rr.UserEmail))
	}

	if len(rr.InboundTag) > 0 {
		conds.Add(NewInboundTagMatcher(rr.InboundTag))
	}

	if rr.PortList != nil {
		conds.Add(NewPortMatcher(rr.PortList, false))
	} else if rr.PortRange != nil {
		conds.Add(NewPortMatcher(&net.PortList{Range: []*net.PortRange{rr.PortRange}}, false))
	}

	if rr.SourcePortList != nil {
		conds.Add(NewPortMatcher(rr.SourcePortList, true))
	}

	if len(rr.Networks) > 0 {
		conds.Add(NewNetworkMatcher(rr.Networks))
	} else if rr.NetworkList != nil {
		conds.Add(NewNetworkMatcher(rr.NetworkList.Network))
	}

	if len(rr.Geoip) > 0 {
		cond, err := geoip.NewMultiGeoIPMatcher(rr.Geoip, false)
		if err != nil {
			return nil, err
		}
		conds.Add(cond)
	} else if len(rr.Cidr) > 0 {
		cond, err := geoip.NewMultiGeoIPMatcher([]*geoip.GeoIP{{Cidr: rr.Cidr}}, false)
		if err != nil {
			return nil, err
		}
		conds.Add(cond)
	}

	if len(rr.SourceGeoip) > 0 {
		cond, err := geoip.NewMultiGeoIPMatcher(rr.SourceGeoip, true)
		if err != nil {
			return nil, err
		}
		conds.Add(cond)
	} else if len(rr.SourceCidr) > 0 {
		cond, err := geoip.NewMultiGeoIPMatcher([]*geoip.GeoIP{{Cidr: rr.SourceCidr}}, true)
		if err != nil {
			return nil, err
		}
		conds.Add(cond)
	}

	if len(rr.Protocol) > 0 {
		conds.Add(NewProtocolMatcher(rr.Protocol))
	}

	if len(rr.Attributes) > 0 {
		cond, err := NewAttributeMatcher(rr.Attributes)
		if err != nil {
			return nil, err
		}
		conds.Add(cond)
	}

	if conds.Len() == 0 {
		return nil, newError("this rule has no effective fields").AtWarning()
	}

	return conds, nil
}

func (br *BalancingRule) Build(ohm outbound.Manager) (*Balancer, error) {
	return &Balancer{
		selectors: br.OutboundSelector,
		strategy:  &RandomStrategy{},
		ohm:       ohm,
	}, nil
}