Implement persistent conversational AI chat

crates/bds-core/src/model/chat.rs

@@ -0,0 +1,109 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(
+    Debug,
+    Clone,
+    Copy,
+    PartialEq,
+    Eq,
+    Serialize,
+    Deserialize,
+    diesel::AsExpression,
+    diesel::FromSqlRow,
+)]
+#[diesel(sql_type = diesel::sql_types::Text)]
+#[serde(rename_all = "lowercase")]
+pub enum ChatRole {
+    System,
+    User,
+    Assistant,
+    Tool,
+}
+
+impl ChatRole {
+    pub const fn as_str(self) -> &'static str {
+        match self {
+            Self::System => "system",
+            Self::User => "user",
+            Self::Assistant => "assistant",
+            Self::Tool => "tool",
+        }
+    }
+}
+
+impl std::str::FromStr for ChatRole {
+    type Err = String;
+
+    fn from_str(value: &str) -> Result<Self, Self::Err> {
+        match value {
+            "system" => Ok(Self::System),
+            "user" => Ok(Self::User),
+            "assistant" => Ok(Self::Assistant),
+            "tool" => Ok(Self::Tool),
+            _ => Err(format!("invalid chat role: {value}")),
+        }
+    }
+}
+
+#[derive(
+    Debug, Clone, PartialEq, Eq, Serialize, Deserialize, diesel::Queryable, diesel::Selectable,
+)]
+#[diesel(
+    table_name = crate::db::schema::chat_conversations,
+    check_for_backend(diesel::sqlite::Sqlite)
+)]
+pub struct ChatConversation {
+    pub id: String,
+    pub title: String,
+    pub model: Option<String>,
+    pub copilot_session_id: Option<String>,
+    pub created_at: i64,
+    pub updated_at: i64,
+}
+
+#[derive(Debug, diesel::Insertable)]
+#[diesel(table_name = crate::db::schema::chat_conversations)]
+pub struct NewChatConversation<'a> {
+    pub id: &'a str,
+    pub title: &'a str,
+    pub model: Option<&'a str>,
+    pub copilot_session_id: Option<&'a str>,
+    pub created_at: i64,
+    pub updated_at: i64,
+}
+
+#[derive(
+    Debug, Clone, PartialEq, Eq, Serialize, Deserialize, diesel::Queryable, diesel::Selectable,
+)]
+#[diesel(
+    table_name = crate::db::schema::chat_messages,
+    check_for_backend(diesel::sqlite::Sqlite)
+)]
+pub struct ChatMessage {
+    pub id: i32,
+    pub conversation_id: String,
+    pub role: ChatRole,
+    pub content: Option<String>,
+    pub tool_call_id: Option<String>,
+    pub tool_calls: Option<String>,
+    pub created_at: i64,
+    pub cache_read_tokens: Option<i32>,
+    pub cache_write_tokens: Option<i32>,
+    pub token_usage_input: Option<i32>,
+    pub token_usage_output: Option<i32>,
+}
+
+#[derive(Debug, diesel::Insertable)]
+#[diesel(table_name = crate::db::schema::chat_messages)]
+pub struct NewChatMessage<'a> {
+    pub conversation_id: &'a str,
+    pub role: ChatRole,
+    pub content: Option<&'a str>,
+    pub tool_call_id: Option<&'a str>,
+    pub tool_calls: Option<&'a str>,
+    pub created_at: i64,
+    pub cache_read_tokens: Option<i32>,
+    pub cache_write_tokens: Option<i32>,
+    pub token_usage_input: Option<i32>,
+    pub token_usage_output: Option<i32>,
+}