1 files changed, 107 insertions, 0 deletions
diff --git a/crates/messenger_common/src/server.rs b/crates/messenger_common/src/server.rs
new file mode 100644
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+++ b/crates/messenger_common/src/server.rs
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+//! Messages sent from the server to the client by the messenger.
+
+use std::collections::HashSet;
+
+use serde::{Deserialize, Serialize};
+use thiserror::Error;
+
+/// Represents the type of message being sent between the client and the server
+#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub enum MessageType {
+	/// Sent to the client to indicate an error made by the client
+	Error(Error),
+
+	/// Sent to a client on the initial join, indicating the online users
+	OnlineUsers(HashSet<String>),
+
+	/// Sent when a user joins the chat. Contains their username
+	UserJoined(String),
+
+	/// Sent when a user disconnects from the chat. Contains their username
+	UserLeft(String),
+
+	/// Sent when a user sends a message in the chat. Contains their message
+	UserMessage(UserMessage),
+}
+
+/// Errors the server may respond with when performing operations
+#[derive(Clone, Debug, Deserialize, Eq, Error, PartialEq, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub enum Error {
+	/// Cannot process the sent message
+	#[error("server cannot process the received message")]
+	CannotProcess,
+
+	/// Message sent was invalid
+	#[error("server received invalid message")]
+	InvalidMessage,
+
+	/// Expected different message than received
+	#[error("server received unexpected message (expected {expected:?}, received {received:?}")]
+	UnexpectedMessage {
+		/// Message the server expected to receive
+		expected: crate::client::MessageType,
+
+		/// Message the server received
+		received: crate::client::MessageType,
+	},
+
+	/// Username chosen is not available
+	#[error("chosen username ({chosen_username}) has already been taken")]
+	UsernameNotAvailable {
+		/// Username that was chosen, but is not available
+		chosen_username: String,
+	},
+}
+
+/// Represents a message sent through a websocket
+#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct UserMessage {
+	/// Content of the message
+	content: String,
+
+	/// The name of the message sender
+	sender: String,
+
+	/// Timestamp indicating when this message was sent
+	#[serde(with = "time::serde::iso8601")]
+	timestamp: time::OffsetDateTime,
+}
+
+impl UserMessage {
+	/// Constructs a new instance of the [`UserMessage`].
+	#[must_use]
+	pub const fn new(content: String, sender: String, timestamp: time::OffsetDateTime) -> Self {
+		Self {
+			content,
+			sender,
+			timestamp,
+		}
+	}
+
+	/// Retrieves a reference to the content of the [`UserMessage`].
+	#[must_use]
+	pub const fn content(&self) -> &String {
+		&self.content
+	}
+
+	/// Retrieves a reference to the sender of the [`UserMessage`].
+	#[must_use]
+	pub const fn sender(&self) -> &String {
+		&self.sender
+	}
+
+	/// Retrieves a timestamp to the content of the [`UserMessage`].
+	#[must_use]
+	pub const fn timestamp(&self) -> &time::OffsetDateTime {
+		&self.timestamp
+	}
+}
+
+impl From<UserMessage> for MessageType {
+	fn from(val: UserMessage) -> Self {
+		Self::UserMessage(val)
+	}
+}