reapply on master (#1067)

docs/API.md

@@ -266,9 +266,9 @@ Called when an error occurs within the client. Takes an Error as parameter.
 ### `playerChat` event
 
 Called when a chat message from another player arrives. The emitted object contains:
-* formattedMessage -- the chat message preformatted, if done on server side
-* plainMessage -- the chat message without formatting (for example no `<username> message` ; instead `message`), on version 1.19+
-* unsignedContent -- unsigned formatted chat contents ; should only be present when the message is modified and server has chat previews disabled - only on version 1.19 - 1.19.2
+* formattedMessage -- (JSON) the chat message preformatted, if done on server side
+* plainMessage -- (Plaintext) the chat message without formatting (for example no `<username> message` ; instead `message`), on version 1.19+
+* unsignedContent -- (JSON) unsigned formatted chat contents ; should only be present when the message is modified and server has chat previews disabled - only on version 1.19 - 1.19.2
 * type -- the message type - on 1.19, which format string to use to render message ; below, the place where the message is displayed (for example chat or action bar)
 * sender -- the UUID of the player sending the message
 * senderTeam -- scoreboard team of the player (pre 1.19)
@@ -279,7 +279,7 @@ Called when a chat message from another player arrives. The emitted object conta
 ### `systemChat` event
 
 Called when a system chat message arrives. A system chat message is any message not sent by a player. The emitted object contains:
-* formattedMessage -- the chat message preformatted
+* formattedMessage -- (JSON) the chat message preformatted
 * positionId -- the chat type of the message. 1 for system chat and 2 for actionbar
 
 See the [chat example](https://github.com/PrismarineJS/node-minecraft-protocol/blob/master/examples/client_chat/client_chat.js#L1) for usage.

src/client/chat.js

@@ -266,7 +266,7 @@ module.exports = function (client, options) {
           plain: packet.plainMessage,
           decorated: packet.formattedMessage
         },
-        messageHash: packet.bodyDigest,
+        messageHash: packet.messageHash,
         timestamp: packet.timestamp,
         salt: packet.salt,
         lastSeen: packet.previousMessages
@@ -297,6 +297,39 @@ module.exports = function (client, options) {
     })
   })
 
+  const sliceIndexForMessage = {}
+  client.on('declare_commands', (packet) => {
+    const nodes = packet.nodes
+    for (const commandNode of nodes[0].children) {
+      const node = nodes[commandNode]
+      const commandName = node.extraNodeData.name
+      function visit (node, depth = 0) {
+        const name = node.extraNodeData.name
+        if (node.extraNodeData.parser === 'minecraft:message') {
+          sliceIndexForMessage[commandName] = [name, depth]
+        }
+        for (const child of node.children) {
+          visit(nodes[child], depth + 1)
+        }
+      }
+      visit(node, 0)
+    }
+  })
+
+  function signaturesForCommand (string, ts, salt) {
+    const signatures = []
+    const slices = string.split(' ')
+    if (sliceIndexForMessage[slices[0]]) {
+      const [fieldName, sliceIndex] = sliceIndexForMessage[slices[0]]
+      const sliced = slices.slice(sliceIndex)
+      if (sliced.length > 0) {
+        const signable = sliced.join(' ')
+        signatures.push({ argumentName: fieldName, signature: client.signMessage(signable, ts, salt) })
+      }
+    }
+    return signatures
+  }
+
   // Chat Sending
   let pendingChatRequest
   let lastPreviewRequestId = 0
@@ -305,6 +338,23 @@ module.exports = function (client, options) {
     options.timestamp = options.timestamp || BigInt(Date.now())
     options.salt = options.salt || 1n
 
+    if (message.startsWith('/') && !mcData.supportFeature('useChatSessions')) {
+      const command = message.slice(1)
+      client.write('chat_command', {
+        command,
+        timestamp: options.timestamp,
+        salt: options.salt,
+        argumentSignatures: signaturesForCommand(command, options.timestamp, options.salt),
+        signedPreview: options.didPreview,
+        previousMessages: client._lastSeenMessages.map((e) => ({
+          messageSender: e.sender,
+          messageSignature: e.signature
+        })),
+        lastRejectedMessage: client._lastRejectedMessage
+      })
+      return
+    }
+
     if (mcData.supportFeature('useChatSessions')) {
       let acc = 0
       const acknowledgements = []
@@ -351,7 +401,7 @@ module.exports = function (client, options) {
         lastRejectedMessage: client._lastRejectedMessage
       })
       client._lastSeenMessages.pending = 0
-    } else {
+    } else if (client.serverFeatures.chatPreview) {
       client.write('chat_preview', {
         query: lastPreviewRequestId,
         message

src/server/chat.js

@@ -7,12 +7,9 @@ const { mojangPublicKeyPem } = require('./constants')
 class VerificationError extends Error {}
 function validateLastMessages (pending, lastSeen, lastRejected) {
   if (lastRejected) {
-    const rejectedTs = pending.get(lastRejected.sender, lastRejected.signature)
-    if (!rejectedTs) {
-      throw new VerificationError(`Client rejected a message we never sent from '${lastRejected.sender}'`)
-    } else {
-      pending.acknowledge(lastRejected.sender, lastRejected.signature)
-    }
+    const rejectedTime = pending.get(lastRejected.sender, lastRejected.signature)
+    if (rejectedTime) pending.acknowledge(lastRejected.sender, lastRejected.signature)
+    else throw new VerificationError(`Client rejected a message we never sent from '${lastRejected.sender}'`)
   }
 
   let lastTimestamp