feat: 恢复上下文解析

src/kiro/model/events/base.rs

@@ -70,7 +70,7 @@ pub enum Event {
     /// 计费
     Metering(()),
     /// 上下文使用率
-    ContextUsage(()),
+    ContextUsage(super::ContextUsageEvent),
     /// 未知事件 (保留原始帧数据)
     Unknown {},
     /// 服务端错误
@@ -120,7 +120,8 @@ impl Event {
                 Ok(Self::Metering(()))
             }
             EventType::ContextUsage => {
-                Ok(Self::ContextUsage(()))
+                let payload = super::ContextUsageEvent::from_frame(&frame)?;
+                Ok(Self::ContextUsage(payload))
             }
             EventType::Unknown => Ok(Self::Unknown {}),
         }

src/kiro/model/events/context_usage.rs

@@ -0,0 +1,90 @@
+//! 上下文使用率事件
+//!
+//! 处理 contextUsageEvent 类型的事件
+
+use serde::Deserialize;
+
+use crate::kiro::parser::error::ParseResult;
+use crate::kiro::parser::frame::Frame;
+
+use super::base::EventPayload;
+
+/// 上下文使用率事件
+///
+/// 包含当前上下文窗口的使用百分比
+#[derive(Debug, Clone, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ContextUsageEvent {
+    /// 上下文使用百分比 (0-100)
+    #[serde(default)]
+    pub context_usage_percentage: f64,
+}
+
+impl EventPayload for ContextUsageEvent {
+    fn from_frame(frame: &Frame) -> ParseResult<Self> {
+        frame.payload_as_json()
+    }
+}
+
+impl ContextUsageEvent {
+    /// 获取格式化的百分比字符串
+    pub fn formatted_percentage(&self) -> String {
+        format!("{:.2}%", self.context_usage_percentage)
+    }
+
+    /// 判断上下文使用是否超过阈值
+    ///
+    /// # Arguments
+    /// * `threshold` - 阈值百分比 (0-100)
+    pub fn exceeds_threshold(&self, threshold: f64) -> bool {
+        self.context_usage_percentage > threshold
+    }
+
+    /// 判断上下文是否接近满 (超过 80%)
+    pub fn is_near_full(&self) -> bool {
+        self.exceeds_threshold(80.0)
+    }
+
+    /// 判断上下文是否已满 (超过 95%)
+    pub fn is_full(&self) -> bool {
+        self.exceeds_threshold(95.0)
+    }
+}
+
+impl std::fmt::Display for ContextUsageEvent {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.formatted_percentage())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_formatted_percentage() {
+        let event = ContextUsageEvent {
+            context_usage_percentage: 50.123,
+        };
+        assert_eq!(event.formatted_percentage(), "50.12%");
+    }
+
+    #[test]
+    fn test_threshold() {
+        let event = ContextUsageEvent {
+            context_usage_percentage: 85.0,
+        };
+        assert!(event.exceeds_threshold(80.0));
+        assert!(!event.exceeds_threshold(90.0));
+        assert!(event.is_near_full());
+        assert!(!event.is_full());
+    }
+
+    #[test]
+    fn test_full() {
+        let event = ContextUsageEvent {
+            context_usage_percentage: 98.0,
+        };
+        assert!(event.is_full());
+    }
+}

src/kiro/model/events/mod.rs

@@ -4,8 +4,10 @@
 
 mod assistant;
 mod base;
+mod context_usage;
 mod tool_use;
 
 pub use assistant::AssistantResponseEvent;
 pub use base::Event;
+pub use context_usage::ContextUsageEvent;
 pub use tool_use::ToolUseEvent;