1 files changed, 304 insertions, 0 deletions
diff --git a/ethchain/filter.go b/ethchain/filter.go
new file mode 100644
index 000000000..5ed9af977
--- /dev/null
+++ b/ethchain/filter.go
@@ -0,0 +1,304 @@
+package ethchain
+
+import (
+	"bytes"
+	"fmt"
+
+	"github.com/ethereum/eth-go/ethstate"
+	"github.com/ethereum/eth-go/ethutil"
+	"gopkg.in/qml.v1"
+)
+
+type data struct {
+	id, address []byte
+}
+
+// Filtering interface
+type Filter struct {
+	eth      EthManager
+	earliest []byte
+	latest   []byte
+	skip     int
+	from, to [][]byte
+	max      int
+
+	altered []data
+}
+
+// Create a new filter which uses a bloom filter on blocks to figure out whether a particular block
+// is interesting or not.
+func NewFilter(eth EthManager) *Filter {
+	return &Filter{eth: eth}
+}
+
+func NewFilterFromMap(object map[string]interface{}, eth EthManager) *Filter {
+	filter := NewFilter(eth)
+
+	if object["earliest"] != nil {
+		earliest := object["earliest"]
+		if e, ok := earliest.(string); ok {
+			filter.SetEarliestBlock(ethutil.Hex2Bytes(e))
+		} else {
+			filter.SetEarliestBlock(earliest)
+		}
+	}
+
+	if object["latest"] != nil {
+		latest := object["latest"]
+		if l, ok := latest.(string); ok {
+			filter.SetLatestBlock(ethutil.Hex2Bytes(l))
+		} else {
+			filter.SetLatestBlock(latest)
+		}
+	}
+
+	if object["to"] != nil {
+		filter.AddTo(ethutil.Hex2Bytes(object["to"].(string)))
+	}
+
+	if object["from"] != nil {
+		filter.AddFrom(ethutil.Hex2Bytes(object["from"].(string)))
+	}
+
+	if object["max"] != nil {
+		filter.SetMax(object["max"].(int))
+	}
+
+	if object["skip"] != nil {
+		filter.SetSkip(object["skip"].(int))
+	}
+
+	if object["altered"] != nil {
+		filter.altered = makeAltered(object["altered"])
+	}
+
+	return filter
+}
+
+func (self *Filter) AddAltered(id, address []byte) {
+	self.altered = append(self.altered, data{id, address})
+}
+
+// Set the earliest and latest block for filtering.
+// -1 = latest block (i.e., the current block)
+// hash = particular hash from-to
+func (self *Filter) SetEarliestBlock(earliest interface{}) {
+	e := ethutil.NewValue(earliest)
+
+	// Check for -1 (latest) otherwise assume bytes
+	if e.Int() == -1 {
+		self.earliest = self.eth.BlockChain().CurrentBlock.Hash()
+	} else if e.Len() > 0 {
+		self.earliest = e.Bytes()
+	} else {
+		panic(fmt.Sprintf("earliest has to be either -1 or a valid hash: %v (%T)", e, e.Val))
+	}
+}
+
+func (self *Filter) SetLatestBlock(latest interface{}) {
+	l := ethutil.NewValue(latest)
+
+	// Check for -1 (latest) otherwise assume bytes
+	if l.Int() == -1 {
+		self.latest = self.eth.BlockChain().CurrentBlock.Hash()
+	} else if l.Len() > 0 {
+		self.latest = l.Bytes()
+	} else {
+		panic(fmt.Sprintf("latest has to be either -1 or a valid hash: %v", l))
+	}
+}
+
+func (self *Filter) SetFrom(addr [][]byte) {
+	self.from = addr
+}
+
+func (self *Filter) AddFrom(addr []byte) {
+	self.from = append(self.from, addr)
+}
+
+func (self *Filter) SetTo(addr [][]byte) {
+	self.to = addr
+}
+
+func (self *Filter) AddTo(addr []byte) {
+	self.to = append(self.to, addr)
+}
+
+func (self *Filter) SetMax(max int) {
+	self.max = max
+}
+
+func (self *Filter) SetSkip(skip int) {
+	self.skip = skip
+}
+
+// Run filters messages with the current parameters set
+func (self *Filter) Find() []*ethstate.Message {
+	var messages []*ethstate.Message
+
+	block := self.eth.BlockChain().GetBlock(self.latest)
+
+	// skip N blocks (useful for pagination)
+	if self.skip > 0 {
+		for i := 0; i < i; i++ {
+			block = self.eth.BlockChain().GetBlock(block.PrevHash)
+		}
+	}
+
+	// Start block filtering
+	quit := false
+	for i := 1; !quit && block != nil; i++ {
+		// Mark last check
+		if self.max == i || (len(self.earliest) > 0 && bytes.Compare(block.Hash(), self.earliest) == 0) {
+			quit = true
+		}
+
+		// Use bloom filtering to see if this block is interesting given the
+		// current parameters
+		if self.bloomFilter(block) {
+			// Get the messages of the block
+			msgs, err := self.eth.StateManager().GetMessages(block)
+			if err != nil {
+				chainlogger.Warnln("err: filter get messages ", err)
+
+				break
+			}
+
+			messages = append(messages, self.FilterMessages(msgs)...)
+		}
+
+		block = self.eth.BlockChain().GetBlock(block.PrevHash)
+	}
+
+	return messages
+}
+
+func includes(addresses [][]byte, a []byte) (found bool) {
+	for _, addr := range addresses {
+		if bytes.Compare(addr, a) == 0 {
+			return true
+		}
+	}
+
+	return
+}
+
+func (self *Filter) FilterMessages(msgs []*ethstate.Message) []*ethstate.Message {
+	var messages []*ethstate.Message
+
+	// Filter the messages for interesting stuff
+	for _, message := range msgs {
+		if len(self.to) > 0 && !includes(self.to, message.To) {
+			continue
+		}
+
+		if len(self.from) > 0 && !includes(self.from, message.From) {
+			continue
+		}
+
+		var match bool
+		if len(self.altered) == 0 {
+			match = true
+		}
+
+		for _, item := range self.altered {
+			if len(item.id) > 0 && bytes.Compare(message.To, item.id) != 0 {
+				continue
+			}
+
+			if len(item.address) > 0 && !includes(message.ChangedAddresses, item.address) {
+				continue
+			}
+
+			match = true
+			break
+		}
+
+		if !match {
+			continue
+		}
+
+		messages = append(messages, message)
+	}
+
+	return messages
+}
+
+func (self *Filter) bloomFilter(block *Block) bool {
+	fk := append([]byte("bloom"), block.Hash()...)
+	bin, err := self.eth.Db().Get(fk)
+	if err != nil {
+		panic(err)
+	}
+
+	bloom := NewBloomFilter(bin)
+
+	var fromIncluded, toIncluded bool
+	if len(self.from) > 0 {
+		for _, from := range self.from {
+			if bloom.Search(from) {
+				fromIncluded = true
+				break
+			}
+		}
+	} else {
+		fromIncluded = true
+	}
+
+	if len(self.to) > 0 {
+		for _, to := range self.to {
+			if bloom.Search(to) {
+				toIncluded = true
+				break
+			}
+		}
+	} else {
+		toIncluded = true
+	}
+
+	return fromIncluded && toIncluded
+}
+
+// Conversion methodn
+func mapToData(m map[string]interface{}) (d data) {
+	if str, ok := m["id"].(string); ok {
+		d.id = ethutil.Hex2Bytes(str)
+	}
+
+	if str, ok := m["at"].(string); ok {
+		d.address = ethutil.Hex2Bytes(str)
+	}
+
+	return
+}
+
+// data can come in in the following formats:
+// ["aabbccdd", {id: "ccddee", at: "11223344"}], "aabbcc", {id: "ccddee", at: "1122"}
+func makeAltered(v interface{}) (d []data) {
+	if str, ok := v.(string); ok {
+		d = append(d, data{ethutil.Hex2Bytes(str), nil})
+	} else if obj, ok := v.(map[string]interface{}); ok {
+		d = append(d, mapToData(obj))
+	} else if slice, ok := v.([]interface{}); ok {
+		for _, item := range slice {
+			d = append(d, makeAltered(item)...)
+		}
+	} else if qList, ok := v.(*qml.List); ok {
+		var s []interface{}
+		qList.Convert(&s)
+
+		fmt.Println(s)
+
+		d = makeAltered(s)
+	} else if qMap, ok := v.(*qml.Map); ok {
+		var m map[string]interface{}
+		qMap.Convert(&m)
+		fmt.Println(m)
+
+		d = makeAltered(m)
+	} else {
+		panic(fmt.Sprintf("makeAltered err (unknown conversion): %T\n", v))
+	}
+
+	return
+}