| 1 | //! Session state management for the core engine. |
| 2 | //! |
| 3 | //! Tracks conversation history, token usage, and session metadata. |
| 4 | |
| 5 | use crate::cycle_manager::CycleBriefing; |
| 6 | use crate::models::{Message, SystemPrompt, Usage}; |
| 7 | use crate::project_context::{ProjectContext, load_project_context_with_parents}; |
| 8 | use crate::tui::approval::ApprovalMode; |
| 9 | use crate::working_set::WorkingSet; |
| 10 | use chrono::{DateTime, Utc}; |
| 11 | use std::path::PathBuf; |
| 12 | |
| 13 | /// Session state for the engine. |
| 14 | #[derive(Debug, Clone)] |
| 15 | pub struct Session { |
| 16 | /// Model being used |
| 17 | pub model: String, |
| 18 | |
| 19 | /// Reasoning-effort tier for DeepSeek thinking mode: |
| 20 | /// `"off" | "low" | "medium" | "high" | "max"`. `None` lets the provider |
| 21 | /// apply its own defaults. |
| 22 | pub reasoning_effort: Option<String>, |
| 23 | /// Whether the user selected automatic reasoning effort. |
| 24 | pub reasoning_effort_auto: bool, |
| 25 | |
| 26 | /// Whether the user selected automatic model routing. |
| 27 | pub auto_model: bool, |
| 28 | |
| 29 | /// Workspace directory |
| 30 | pub workspace: PathBuf, |
| 31 | |
| 32 | /// System prompt (optional) |
| 33 | pub system_prompt: Option<SystemPrompt>, |
| 34 | /// Hash of the last assembled stable system prompt. Used to avoid |
| 35 | /// replacing `system_prompt` when unchanged. |
| 36 | pub last_system_prompt_hash: Option<u64>, |
| 37 | /// Persisted summary blocks generated by context compaction. |
| 38 | pub compaction_summary_prompt: Option<SystemPrompt>, |
| 39 | |
| 40 | /// Conversation history (API format) |
| 41 | pub messages: Vec<Message>, |
| 42 | |
| 43 | /// Total tokens used in this session |
| 44 | pub total_usage: SessionUsage, |
| 45 | |
| 46 | /// Whether shell execution is allowed |
| 47 | pub allow_shell: bool, |
| 48 | |
| 49 | /// Whether to trust paths outside workspace |
| 50 | pub trust_mode: bool, |
| 51 | |
| 52 | /// Whether the current session should auto-approve tool safety checks. |
| 53 | pub auto_approve: bool, |
| 54 | |
| 55 | /// Live UI approval policy used to steer the system prompt. |
| 56 | pub approval_mode: ApprovalMode, |
| 57 | |
| 58 | /// Notes file path |
| 59 | pub notes_path: PathBuf, |
| 60 | |
| 61 | /// MCP config path |
| 62 | pub mcp_config_path: PathBuf, |
| 63 | |
| 64 | /// Session ID (for tracking) |
| 65 | pub id: String, |
| 66 | |
| 67 | /// Project context loaded from AGENTS.md, etc. |
| 68 | pub project_context: Option<ProjectContext>, |
| 69 | |
| 70 | /// Repo-aware working set for context management. |
| 71 | pub working_set: WorkingSet, |
| 72 | |
| 73 | /// Number of cycle boundaries crossed in this session (issue #124). The |
| 74 | /// active cycle index is `cycle_count + 1` (cycles are 1-based for users). |
| 75 | pub cycle_count: u32, |
| 76 | |
| 77 | /// UTC start time of the *current* cycle. Updated when the engine resets |
| 78 | /// the conversation buffer. Used by archive headers and the `/cycles` |
| 79 | /// command's display. |
| 80 | pub current_cycle_started: DateTime<Utc>, |
| 81 | |
| 82 | /// Briefings produced at past cycle boundaries, in chronological order. |
| 83 | /// Bounded growth: one entry per cycle, briefing capped at ~3,000 tokens. |
| 84 | pub cycle_briefings: Vec<CycleBriefing>, |
| 85 | } |
| 86 | |
| 87 | /// Cumulative usage statistics for a session. |
| 88 | #[derive(Debug, Clone, Default)] |
| 89 | #[allow(clippy::struct_field_names)] |
| 90 | pub struct SessionUsage { |
| 91 | pub input_tokens: u64, |
| 92 | pub output_tokens: u64, |
| 93 | #[allow(dead_code)] |
| 94 | pub cache_creation_input_tokens: u64, |
| 95 | #[allow(dead_code)] |
| 96 | pub cache_read_input_tokens: u64, |
| 97 | } |
| 98 | |
| 99 | impl SessionUsage { |
| 100 | /// Add usage from a turn |
| 101 | pub fn add(&mut self, usage: &Usage) { |
| 102 | self.input_tokens += u64::from(usage.input_tokens); |
| 103 | self.output_tokens += u64::from(usage.output_tokens); |
| 104 | if let Some(tokens) = usage.prompt_cache_miss_tokens { |
| 105 | self.cache_creation_input_tokens += u64::from(tokens); |
| 106 | } |
| 107 | if let Some(tokens) = usage.prompt_cache_hit_tokens { |
| 108 | self.cache_read_input_tokens += u64::from(tokens); |
| 109 | } |
| 110 | } |
| 111 | } |
| 112 | |
| 113 | impl Session { |
| 114 | /// Create a new session |
| 115 | pub fn new( |
| 116 | model: String, |
| 117 | workspace: PathBuf, |
| 118 | allow_shell: bool, |
| 119 | trust_mode: bool, |
| 120 | notes_path: PathBuf, |
| 121 | mcp_config_path: PathBuf, |
| 122 | ) -> Self { |
| 123 | // Load project context from AGENTS.md, CLAUDE.md, etc. |
| 124 | let project_context = load_project_context_with_parents(&workspace); |
| 125 | let has_context = project_context.has_instructions(); |
| 126 | |
| 127 | Self { |
| 128 | model, |
| 129 | reasoning_effort: None, |
| 130 | reasoning_effort_auto: false, |
| 131 | auto_model: false, |
| 132 | workspace, |
| 133 | system_prompt: None, |
| 134 | compaction_summary_prompt: None, |
| 135 | messages: Vec::new(), |
| 136 | total_usage: SessionUsage::default(), |
| 137 | allow_shell, |
| 138 | trust_mode, |
| 139 | auto_approve: false, |
| 140 | approval_mode: ApprovalMode::Suggest, |
| 141 | notes_path, |
| 142 | mcp_config_path, |
| 143 | id: uuid::Uuid::new_v4().to_string(), |
| 144 | project_context: if has_context { |
| 145 | Some(project_context) |
| 146 | } else { |
| 147 | None |
| 148 | }, |
| 149 | last_system_prompt_hash: None, |
| 150 | working_set: WorkingSet::default(), |
| 151 | cycle_count: 0, |
| 152 | current_cycle_started: Utc::now(), |
| 153 | cycle_briefings: Vec::new(), |
| 154 | } |
| 155 | } |
| 156 | |
| 157 | /// Add a message to the conversation |
| 158 | pub fn add_message(&mut self, message: Message) { |
| 159 | self.messages.push(message); |
| 160 | } |
| 161 | |
| 162 | /// Rebuild the working set from current messages (best effort). |
| 163 | pub fn rebuild_working_set(&mut self) { |
| 164 | self.working_set |
| 165 | .rebuild_from_messages(&self.messages, &self.workspace); |
| 166 | } |
| 167 | } |
| 168 |