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// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package whisperv5

import (
    "bytes"
    "encoding/json"
    "testing"
    "time"

    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/common/hexutil"
)

func TestBasic(t *testing.T) {
    var id string = "test"
    w := New()
    api := NewPublicWhisperAPI(w)
    if api == nil {
        t.Fatalf("failed to create API.")
    }

    ver, err := api.Version()
    if err != nil {
        t.Fatalf("failed generateFilter: %s.", err)
    }

    if uint64(ver) != ProtocolVersion {
        t.Fatalf("wrong version: %d.", ver)
    }

    mail := api.GetSubscriptionMessages("non-existent-id")
    if len(mail) != 0 {
        t.Fatalf("failed GetFilterChanges: premature result")
    }

    exist, err := api.HasKeyPair(id)
    if err != nil {
        t.Fatalf("failed initial HasIdentity: %s.", err)
    }
    if exist {
        t.Fatalf("failed initial HasIdentity: false positive.")
    }

    success, err := api.DeleteKeyPair(id)
    if err != nil {
        t.Fatalf("failed DeleteIdentity: %s.", err)
    }
    if success {
        t.Fatalf("deleted non-existing identity: false positive.")
    }

    pub, err := api.NewKeyPair()
    if err != nil {
        t.Fatalf("failed NewIdentity: %s.", err)
    }
    if len(pub) == 0 {
        t.Fatalf("failed NewIdentity: empty")
    }

    exist, err = api.HasKeyPair(pub)
    if err != nil {
        t.Fatalf("failed HasIdentity: %s.", err)
    }
    if !exist {
        t.Fatalf("failed HasIdentity: false negative.")
    }

    success, err = api.DeleteKeyPair(pub)
    if err != nil {
        t.Fatalf("failed to delete second identity: %s.", err)
    }
    if !success {
        t.Fatalf("failed to delete second identity.")
    }

    exist, err = api.HasKeyPair(pub)
    if err != nil {
        t.Fatalf("failed HasIdentity(): %s.", err)
    }
    if exist {
        t.Fatalf("failed HasIdentity(): false positive.")
    }

    id = "arbitrary text"
    id2 := "another arbitrary string"

    exist, err = api.HasSymmetricKey(id)
    if err != nil {
        t.Fatalf("failed HasSymKey: %s.", err)
    }
    if exist {
        t.Fatalf("failed HasSymKey: false positive.")
    }

    id, err = api.GenerateSymmetricKey()
    if err != nil {
        t.Fatalf("failed GenerateSymKey: %s.", err)
    }

    exist, err = api.HasSymmetricKey(id)
    if err != nil {
        t.Fatalf("failed HasSymKey(): %s.", err)
    }
    if !exist {
        t.Fatalf("failed HasSymKey(): false negative.")
    }

    const password = "some stuff here"
    id, err = api.AddSymmetricKeyFromPassword(password)
    if err != nil {
        t.Fatalf("failed AddSymKey: %s.", err)
    }

    id2, err = api.AddSymmetricKeyFromPassword(password)
    if err != nil {
        t.Fatalf("failed AddSymKey: %s.", err)
    }

    exist, err = api.HasSymmetricKey(id2)
    if err != nil {
        t.Fatalf("failed HasSymKey(id2): %s.", err)
    }
    if !exist {
        t.Fatalf("failed HasSymKey(id2): false negative.")
    }

    k1, err := api.GetSymmetricKey(id)
    if err != nil {
        t.Fatalf("failed GetSymKey(id): %s.", err)
    }
    k2, err := api.GetSymmetricKey(id2)
    if err != nil {
        t.Fatalf("failed GetSymKey(id2): %s.", err)
    }

    if !bytes.Equal(k1, k2) {
        t.Fatalf("installed keys are not equal")
    }

    exist, err = api.DeleteSymmetricKey(id)
    if err != nil {
        t.Fatalf("failed DeleteSymKey(id): %s.", err)
    }
    if !exist {
        t.Fatalf("failed DeleteSymKey(id): false negative.")
    }

    exist, err = api.HasSymmetricKey(id)
    if err != nil {
        t.Fatalf("failed HasSymKey(id): %s.", err)
    }
    if exist {
        t.Fatalf("failed HasSymKey(id): false positive.")
    }
}

func TestUnmarshalFilterArgs(t *testing.T) {
    s := []byte(`{
    "type":"sym",
    "key":"0x70c87d191324e6712a591f304b4eedef6ad9bb9d",
    "signedWith":"0x9b2055d370f73ec7d8a03e965129118dc8f5bf83",
    "minPoW":2.34,
    "topics":["0x00000000", "0x007f80ff", "0xff807f00", "0xf26e7779"],
    "allowP2P":true
    }`)

    var f WhisperFilterArgs
    err := f.UnmarshalJSON(s)
    if err != nil {
        t.Fatalf("failed UnmarshalJSON: %s.", err)
    }

    if !f.Symmetric {
        t.Fatalf("wrong type.")
    }
    if f.Key != "0x70c87d191324e6712a591f304b4eedef6ad9bb9d" {
        t.Fatalf("wrong key: %s.", f.Key)
    }
    if f.SignedWith != "0x9b2055d370f73ec7d8a03e965129118dc8f5bf83" {
        t.Fatalf("wrong SignedWith: %s.", f.SignedWith)
    }
    if f.MinPoW != 2.34 {
        t.Fatalf("wrong MinPoW: %f.", f.MinPoW)
    }
    if !f.AllowP2P {
        t.Fatalf("wrong AllowP2P.")
    }
    if len(f.Topics) != 4 {
        t.Fatalf("wrong topics number: %d.", len(f.Topics))
    }

    i := 0
    if !bytes.Equal(f.Topics[i], []byte{0x00, 0x00, 0x00, 0x00}) {
        t.Fatalf("wrong topic[%d]: %x.", i, f.Topics[i])
    }

    i++
    if !bytes.Equal(f.Topics[i], []byte{0x00, 0x7f, 0x80, 0xff}) {
        t.Fatalf("wrong topic[%d]: %x.", i, f.Topics[i])
    }

    i++
    if !bytes.Equal(f.Topics[i], []byte{0xff, 0x80, 0x7f, 0x00}) {
        t.Fatalf("wrong topic[%d]: %x.", i, f.Topics[i])
    }

    i++
    if !bytes.Equal(f.Topics[i], []byte{0xf2, 0x6e, 0x77, 0x79}) {
        t.Fatalf("wrong topic[%d]: %x.", i, f.Topics[i])
    }
}

func TestUnmarshalPostArgs(t *testing.T) {
    s := []byte(`{
    "type":"sym",
    "ttl":12345,
    "signWith":"0x70c87d191324e6712a591f304b4eedef6ad9bb9d",
    "key":"0x9b2055d370f73ec7d8a03e965129118dc8f5bf83",
    "topic":"0xf26e7779",
    "padding":"0x74686973206973206D79207465737420737472696E67",
    "payload":"0x7061796C6F61642073686F756C642062652070736575646F72616E646F6D",
    "powTime":777,
    "powTarget":3.1416,
    "targetPeer":"enode://915533f667b1369793ebb9bda022416b1295235a1420799cd87a969467372546d808ebf59c5c9ce23f103d59b61b97df8af91f0908552485975397181b993461@127.0.0.1:12345"
    }`)

    var a PostArgs
    err := json.Unmarshal(s, &a)
    if err != nil {
        t.Fatalf("failed UnmarshalJSON: %s.", err)
    }

    if a.Type != "sym" {
        t.Fatalf("wrong Type: %s.", a.Type)
    }
    if a.TTL != 12345 {
        t.Fatalf("wrong ttl: %d.", a.TTL)
    }
    if a.SignWith != "0x70c87d191324e6712a591f304b4eedef6ad9bb9d" {
        t.Fatalf("wrong From: %s.", a.SignWith)
    }
    if a.Key != "0x9b2055d370f73ec7d8a03e965129118dc8f5bf83" {
        t.Fatalf("wrong Key: %s.", a.Key)
    }

    if BytesToTopic(a.Topic) != (TopicType{0xf2, 0x6e, 0x77, 0x79}) {
        t.Fatalf("wrong topic: %x.", a.Topic)
    }
    if string(a.Padding) != "this is my test string" {
        t.Fatalf("wrong Padding: %s.", string(a.Padding))
    }
    if string(a.Payload) != "payload should be pseudorandom" {
        t.Fatalf("wrong Payload: %s.", string(a.Payload))
    }
    if a.PowTime != 777 {
        t.Fatalf("wrong PowTime: %d.", a.PowTime)
    }
    if a.PowTarget != 3.1416 {
        t.Fatalf("wrong PowTarget: %f.", a.PowTarget)
    }
    if a.TargetPeer != "enode://915533f667b1369793ebb9bda022416b1295235a1420799cd87a969467372546d808ebf59c5c9ce23f103d59b61b97df8af91f0908552485975397181b993461@127.0.0.1:12345" {
        t.Fatalf("wrong PeerID: %s.", a.TargetPeer)
    }
}

func waitForMessages(api *PublicWhisperAPI, id string, target int) []*WhisperMessage {
    // timeout: 2 seconds
    result := make([]*WhisperMessage, 0, target)
    for i := 0; i < 100; i++ {
        mail := api.GetSubscriptionMessages(id)
        if len(mail) > 0 {
            for _, m := range mail {
                result = append(result, m)
            }
            if len(result) >= target {
                break
            }
        }
        time.Sleep(time.Millisecond * 20)
    }

    return result
}

func TestIntegrationAsym(t *testing.T) {
    w := New()
    api := NewPublicWhisperAPI(w)
    if api == nil {
        t.Fatalf("failed to create API.")
    }

    api.Start()
    defer api.Stop()

    sig, err := api.NewKeyPair()
    if err != nil {
        t.Fatalf("failed NewIdentity: %s.", err)
    }
    if len(sig) == 0 {
        t.Fatalf("wrong signature")
    }

    exist, err := api.HasKeyPair(sig)
    if err != nil {
        t.Fatalf("failed HasIdentity: %s.", err)
    }
    if !exist {
        t.Fatalf("failed HasIdentity: false negative.")
    }

    sigPubKey, err := api.GetPublicKey(sig)
    if err != nil {
        t.Fatalf("failed GetPublicKey: %s.", err)
    }

    key, err := api.NewKeyPair()
    if err != nil {
        t.Fatalf("failed NewIdentity(): %s.", err)
    }
    if len(key) == 0 {
        t.Fatalf("wrong key")
    }

    dstPubKey, err := api.GetPublicKey(key)
    if err != nil {
        t.Fatalf("failed GetPublicKey: %s.", err)
    }

    var topics [2]TopicType
    topics[0] = TopicType{0x00, 0x64, 0x00, 0xff}
    topics[1] = TopicType{0xf2, 0x6e, 0x77, 0x79}
    var f WhisperFilterArgs
    f.Symmetric = false
    f.Key = key
    f.SignedWith = sigPubKey.String()
    f.Topics = make([][]byte, 2)
    f.Topics[0] = topics[0][:]
    f.Topics[1] = topics[1][:]
    f.MinPoW = DefaultMinimumPoW / 2
    f.AllowP2P = true

    id, err := api.Subscribe(f)
    if err != nil {
        t.Fatalf("failed to create new filter: %s.", err)
    }

    var p PostArgs
    p.Type = "asym"
    p.TTL = 2
    p.SignWith = sig
    p.Key = dstPubKey.String()
    p.Padding = []byte("test string")
    p.Payload = []byte("extended test string")
    p.PowTarget = DefaultMinimumPoW
    p.PowTime = 2
    p.Topic = hexutil.Bytes{0xf2, 0x6e, 0x77, 0x79} // topics[1]

    err = api.Post(p)
    if err != nil {
        t.Errorf("failed to post message: %s.", err)
    }

    mail := waitForMessages(api, id, 1)
    if len(mail) != 1 {
        t.Fatalf("failed to GetFilterChanges: got %d messages.", len(mail))
    }

    text := string(common.FromHex(mail[0].Payload))
    if text != string("extended test string") {
        t.Fatalf("failed to decrypt first message: %s.", text)
    }

    p.Padding = []byte("new value")
    p.Payload = []byte("extended new value")
    err = api.Post(p)
    if err != nil {
        t.Fatalf("failed to post next message: %s.", err)
    }

    mail = waitForMessages(api, id, 1)
    if len(mail) != 1 {
        t.Fatalf("failed to GetFilterChanges: got %d messages.", len(mail))
    }

    text = string(common.FromHex(mail[0].Payload))
    if text != string("extended new value") {
        t.Fatalf("failed to decrypt second message: %s.", text)
    }
}

func TestIntegrationSym(t *testing.T) {
    w := New()
    api := NewPublicWhisperAPI(w)
    if api == nil {
        t.Fatalf("failed to create API.")
    }

    api.Start()
    defer api.Stop()

    symKeyID, err := api.GenerateSymmetricKey()
    if err != nil {
        t.Fatalf("failed GenerateSymKey: %s.", err)
    }

    sig, err := api.NewKeyPair()
    if err != nil {
        t.Fatalf("failed NewKeyPair: %s.", err)
    }
    if len(sig) == 0 {
        t.Fatalf("wrong signature")
    }

    sigPubKey, err := api.GetPublicKey(sig)
    if err != nil {
        t.Fatalf("failed GetPublicKey: %s.", err)
    }

    exist, err := api.HasKeyPair(sig)
    if err != nil {
        t.Fatalf("failed HasIdentity: %s.", err)
    }
    if !exist {
        t.Fatalf("failed HasIdentity: false negative.")
    }

    var topics [2]TopicType
    topics[0] = TopicType{0x00, 0x7f, 0x80, 0xff}
    topics[1] = TopicType{0xf2, 0x6e, 0x77, 0x79}
    var f WhisperFilterArgs
    f.Symmetric = true
    f.Key = symKeyID
    f.Topics = make([][]byte, 2)
    f.Topics[0] = topics[0][:]
    f.Topics[1] = topics[1][:]
    f.MinPoW = 0.324
    f.SignedWith = sigPubKey.String()
    f.AllowP2P = false

    id, err := api.Subscribe(f)
    if err != nil {
        t.Fatalf("failed to create new filter: %s.", err)
    }

    var p PostArgs
    p.Type = "sym"
    p.TTL = 1
    p.Key = symKeyID
    p.SignWith = sig
    p.Padding = []byte("test string")
    p.Payload = []byte("extended test string")
    p.PowTarget = DefaultMinimumPoW
    p.PowTime = 2
    p.Topic = hexutil.Bytes{0xf2, 0x6e, 0x77, 0x79}

    err = api.Post(p)
    if err != nil {
        t.Fatalf("failed to post first message: %s.", err)
    }

    mail := waitForMessages(api, id, 1)
    if len(mail) != 1 {
        t.Fatalf("failed GetFilterChanges: got %d messages.", len(mail))
    }

    text := string(common.FromHex(mail[0].Payload))
    if text != string("extended test string") {
        t.Fatalf("failed to decrypt first message: %s.", text)
    }

    p.Padding = []byte("new value")
    p.Payload = []byte("extended new value")
    err = api.Post(p)
    if err != nil {
        t.Fatalf("failed to post second message: %s.", err)
    }

    mail = waitForMessages(api, id, 1)
    if len(mail) != 1 {
        t.Fatalf("failed second GetFilterChanges: got %d messages.", len(mail))
    }

    text = string(common.FromHex(mail[0].Payload))
    if text != string("extended new value") {
        t.Fatalf("failed to decrypt second message: %s.", text)
    }
}

func TestIntegrationSymWithFilter(t *testing.T) {
    w := New()
    api := NewPublicWhisperAPI(w)
    if api == nil {
        t.Fatalf("failed to create API.")
    }

    api.Start()
    defer api.Stop()

    symKeyID, err := api.GenerateSymmetricKey()
    if err != nil {
        t.Fatalf("failed to GenerateSymKey: %s.", err)
    }

    sigKeyID, err := api.NewKeyPair()
    if err != nil {
        t.Fatalf("failed NewIdentity: %s.", err)
    }
    if len(sigKeyID) == 0 {
        t.Fatalf("wrong signature.")
    }

    exist, err := api.HasKeyPair(sigKeyID)
    if err != nil {
        t.Fatalf("failed HasIdentity: %s.", err)
    }
    if !exist {
        t.Fatalf("failed HasIdentity: does not exist.")
    }

    sigPubKey, err := api.GetPublicKey(sigKeyID)
    if err != nil {
        t.Fatalf("failed GetPublicKey: %s.", err)
    }

    var topics [2]TopicType
    topics[0] = TopicType{0x00, 0x7f, 0x80, 0xff}
    topics[1] = TopicType{0xf2, 0x6e, 0x77, 0x79}
    var f WhisperFilterArgs
    f.Symmetric = true
    f.Key = symKeyID
    f.Topics = make([][]byte, 2)
    f.Topics[0] = topics[0][:]
    f.Topics[1] = topics[1][:]
    f.MinPoW = 0.324
    f.SignedWith = sigPubKey.String()
    f.AllowP2P = false

    id, err := api.Subscribe(f)
    if err != nil {
        t.Fatalf("failed to create new filter: %s.", err)
    }

    var p PostArgs
    p.Type = "sym"
    p.TTL = 1
    p.Key = symKeyID
    p.SignWith = sigKeyID
    p.Padding = []byte("test string")
    p.Payload = []byte("extended test string")
    p.PowTarget = DefaultMinimumPoW
    p.PowTime = 2
    p.Topic = hexutil.Bytes{0xf2, 0x6e, 0x77, 0x79}

    err = api.Post(p)
    if err != nil {
        t.Fatalf("failed to post message: %s.", err)
    }

    mail := waitForMessages(api, id, 1)
    if len(mail) != 1 {
        t.Fatalf("failed to GetFilterChanges: got %d messages.", len(mail))
    }

    text := string(common.FromHex(mail[0].Payload))
    if text != string("extended test string") {
        t.Fatalf("failed to decrypt first message: %s.", text)
    }

    p.Padding = []byte("new value")
    p.Payload = []byte("extended new value")
    err = api.Post(p)
    if err != nil {
        t.Fatalf("failed to post next message: %s.", err)
    }

    mail = waitForMessages(api, id, 1)
    if len(mail) != 1 {
        t.Fatalf("failed to GetFilterChanges: got %d messages.", len(mail))
    }

    text = string(common.FromHex(mail[0].Payload))
    if text != string("extended new value") {
        t.Fatalf("failed to decrypt second message: %s.", text)
    }
}

func TestKey(t *testing.T) {
    w := New()
    api := NewPublicWhisperAPI(w)
    if api == nil {
        t.Fatalf("failed to create API.")
    }

    k, err := api.AddSymmetricKeyFromPassword("wwww")
    if err != nil {
        t.Fatalf("failed to create key: %s.", err)
    }

    s, err := api.GetSymmetricKey(k)
    if err != nil {
        t.Fatalf("failed to get sym key: %s.", err)
    }

    k2, err := api.AddSymmetricKeyDirect(s)
    if err != nil {
        t.Fatalf("failed to add sym key: %s.", err)
    }

    s2, err := api.GetSymmetricKey(k2)
    if err != nil {
        t.Fatalf("failed to get sym key: %s.", err)
    }

    if s.String() != "0x448652d595bd6ec00b2a9ea220ad6c26592d9bf4cf79023d3c1b30cb681e6e07" {
        t.Fatalf("wrong key from password: %s", s.String())
    }

    if !bytes.Equal(s, s2) {
        t.Fatalf("wrong key")
    }
}

func TestSubscribe(t *testing.T) {
    var err error
    var s string

    w := New()
    api := NewPublicWhisperAPI(w)
    if api == nil {
        t.Fatalf("failed to create API.")
    }

    symKeyID, err := api.GenerateSymmetricKey()
    if err != nil {
        t.Fatalf("failed to GenerateSymKey: %s.", err)
    }

    var f WhisperFilterArgs
    f.Symmetric = true
    f.Key = symKeyID
    f.Topics = make([][]byte, 5)
    f.Topics[0] = []byte{0x21}
    f.Topics[1] = []byte{0xd2, 0xe3}
    f.Topics[2] = []byte{0x64, 0x75, 0x76}
    f.Topics[3] = []byte{0xf8, 0xe9, 0xa0, 0xba}
    f.Topics[4] = []byte{0xcb, 0x3c, 0xdd, 0xee, 0xff}

    s, err = api.Subscribe(f)
    if err == nil {
        t.Fatalf("Subscribe: false positive.")
    }

    f.Topics[4] = []byte{}
    if err == nil {
        t.Fatalf("Subscribe: false positive again.")
    }

    f.Topics[4] = []byte{0x00}
    s, err = api.Subscribe(f)
    if err != nil {
        t.Fatalf("failed to subscribe: %s.", err)
    } else {
        api.Unsubscribe(s)
    }
}