From 548dac1a11b789743104ce5d64a15c098c6f7628 Mon Sep 17 00:00:00 2001
From: bemasher <bemasher@gmail.com>
Date: Sat, 11 Jul 2015 03:45:27 -0600
Subject: [PATCH] Refactor message filtering.

---
 flags.go       | 34 ++++++++++++++++++++++++++++++++++
 parse/parse.go | 24 ++++++++++++++++++++++++
 recv.go        | 31 ++++++++++++-------------------
 3 files changed, 70 insertions(+), 19 deletions(-)

diff --git a/flags.go b/flags.go
index 08242740b..09e3e7fb3 100644
--- a/flags.go
+++ b/flags.go
@@ -17,6 +17,7 @@
 package main
 
 import (
+	"bytes"
 	"encoding/gob"
 	"encoding/json"
 	"encoding/xml"
@@ -28,6 +29,7 @@ import (
 	"strings"
 
 	"github.com/bemasher/rtlamr/csv"
+	"github.com/bemasher/rtlamr/parse"
 )
 
 var logFilename = flag.String("logfile", "/dev/stdout", "log statement dump file")
@@ -45,6 +47,7 @@ var decimation = flag.Int("decimation", 1, "integer decimation factor, keep ever
 var timeLimit = flag.Duration("duration", 0, "time to run for, 0 for infinite, ex. 1h5m10s")
 var meterID UintMap
 var meterType UintMap
+
 var unique = flag.Bool("unique", false, "suppress duplicate messages from each meter")
 
 var encoder Encoder
@@ -167,3 +170,34 @@ func (m UintMap) Set(value string) error {
 
 	return nil
 }
+
+type MeterIDFilter UintMap
+
+func (m MeterIDFilter) Filter(msg parse.Message) bool {
+	return m[uint(msg.MeterID())]
+}
+
+type MeterTypeFilter UintMap
+
+func (m MeterTypeFilter) Filter(msg parse.Message) bool {
+	return m[uint(msg.MeterType())]
+}
+
+type UniqueFilter map[uint][]byte
+
+func NewUniqueFilter() UniqueFilter {
+	return make(UniqueFilter)
+}
+
+func (uf UniqueFilter) Filter(msg parse.Message) bool {
+	checksum := msg.Checksum()
+	mid := uint(msg.MeterID())
+
+	if val, ok := uf[mid]; ok && bytes.Compare(val, checksum) == 0 {
+		return false
+	}
+
+	uf[mid] = make([]byte, len(checksum))
+	copy(uf[mid], checksum)
+	return true
+}
diff --git a/parse/parse.go b/parse/parse.go
index 7aa43cb37..565585fb8 100644
--- a/parse/parse.go
+++ b/parse/parse.go
@@ -77,3 +77,27 @@ func (msg LogMessage) Record() (r []string) {
 	r = append(r, msg.Message.Record()...)
 	return r
 }
+
+type FilterChain []Filter
+
+func (fc *FilterChain) Add(filter Filter) {
+	*fc = append(*fc, filter)
+}
+
+func (fc FilterChain) Match(msg Message) bool {
+	if len(fc) == 0 {
+		return true
+	}
+
+	for _, filter := range fc {
+		if !filter.Filter(msg) {
+			return false
+		}
+	}
+
+	return true
+}
+
+type Filter interface {
+	Filter(Message) bool
+}
diff --git a/recv.go b/recv.go
index 8f9045edb..d99ac189c 100644
--- a/recv.go
+++ b/recv.go
@@ -17,7 +17,6 @@
 package main
 
 import (
-	"bytes"
 	"encoding/xml"
 	"flag"
 	"fmt"
@@ -40,7 +39,8 @@ var rcvr Receiver
 
 type Receiver struct {
 	rtltcp.SDR
-	p parse.Parser
+	p  parse.Parser
+	fc parse.FilterChain
 }
 
 func (rcvr *Receiver) NewReceiver() {
@@ -82,8 +82,17 @@ func (rcvr *Receiver) NewReceiver() {
 			sampleRateFlagSet = true
 		case "gainbyindex", "tunergainmode", "tunergain", "agcmode":
 			gainFlagSet = true
+		case "unique":
+			rcvr.fc.Add(NewUniqueFilter())
+		case "filterid":
+			rcvr.fc.Add(MeterIDFilter(meterID))
+		case "filtertype":
+			rcvr.fc.Add(MeterTypeFilter(meterType))
+		default:
+			fmt.Println(f.Name)
 		}
 	})
+	fmt.Printf("%+v\n", rcvr.fc)
 
 	// Set some parameters for listening.
 	if centerfreqFlagSet {
@@ -127,7 +136,6 @@ func (rcvr *Receiver) Run() {
 	}()
 
 	block := make([]byte, rcvr.p.Cfg().BlockSize2)
-	checksumHistory := make(map[uint][]byte)
 
 	start := time.Now()
 	for {
@@ -149,24 +157,9 @@ func (rcvr *Receiver) Run() {
 			indices := rcvr.p.Dec().Decode(block)
 
 			for _, pkt := range rcvr.p.Parse(indices) {
-				if len(meterID) > 0 && !meterID[uint(pkt.MeterID())] {
-					continue
-				}
-
-				if len(meterType) > 0 && !meterType[uint(pkt.MeterType())] {
+				if !rcvr.fc.Match(pkt) {
 					continue
 				}
-				if *unique {
-					checksum := pkt.Checksum()
-					mid := uint(pkt.MeterID())
-
-					if val, ok := checksumHistory[mid]; ok && bytes.Compare(val, checksum) == 0 {
-						continue
-					}
-
-					checksumHistory[mid] = make([]byte, len(checksum))
-					copy(checksumHistory[mid], checksum)
-				}
 
 				var msg parse.LogMessage
 				msg.Time = time.Now()