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trustee_core/
session.rs

1//! Session state — core agent session without any UI concerns.
2//!
3//! This struct holds all the state shared between frontends (TUI, API, Web):
4//! output lines, input, workflow state, config, resume info, MCP servers, etc.
5
6use std::collections::HashMap;
7use std::sync::Arc;
8
9use tokio::sync::mpsc;
10use tokio_util::sync::CancellationToken;
11
12use abk::cli::ResumeInfo;
13use abk::context::RunContext;
14
15use std::sync::atomic::{AtomicU8, Ordering};
16
17use crate::types::{
18    AutoHandoffConfig, BuildInfo, CapturedText, HandoffCaptureSink, McpServerInfo, McpServerStatus,
19    TuiMessage, WorkflowState,
20};
21
22/// Core session state for the Trustee agent.
23///
24/// Holds all state that is independent of the presentation layer (TUI, API, Web).
25/// Frontend crates compose this struct and add their own UI-specific fields.
26pub struct Session {
27    /// Input buffer for user commands
28    pub input: String,
29    /// Output log lines
30    pub output_lines: Vec<String>,
31    /// Sender for messages from async workflows (clone and pass to workflow runners)
32    pub workflow_tx: mpsc::UnboundedSender<TuiMessage>,
33    /// Current workflow lifecycle state
34    pub workflow_state: WorkflowState,
35    /// Configuration TOML for ABK workflows
36    pub config_toml: Option<String>,
37    /// Secrets for ABK workflows
38    pub secrets: Option<HashMap<String, String>>,
39    /// Build info for ABK workflows
40    pub build_info: Option<BuildInfo>,
41    /// Resume info from the last completed task for session continuity
42    pub resume_info: Option<ResumeInfo>,
43    /// Saved resume_info before execute_command consumes it; restored if task
44    /// is cancelled before producing a real checkpoint (mistake-ENTER recovery).
45    pub backup_resume_info: Option<ResumeInfo>,
46    /// Latest todo list from LLM todowrite tool
47    pub todo_lines: Vec<String>,
48    /// Cancellation token for aborting the current workflow
49    pub cancel_token: CancellationToken,
50    /// Command buffered by user during cancellation wind-down.
51    pub pending_command: Option<String>,
52    /// Whether a session handoff (Ctrl+H) should fire once the current workflow cancels.
53    pub handoff_pending: bool,
54    /// In-flight spinner entries: (tool_name, output_lines_index, hint).
55    pub pending_tool_lines: Vec<(String, usize, Option<String>)>,
56    /// Current context token count (updated from ApiCallStarted events).
57    pub current_context_tokens: usize,
58    /// Auto-handoff configuration parsed from [tui.auto_handoff].
59    pub auto_handoff: AutoHandoffConfig,
60    /// MCP server statuses received from agent init
61    pub mcp_servers: Vec<McpServerInfo>,
62    /// Whether the session should quit
63    pub should_quit: bool,
64    /// Whether auto-scroll is enabled (follows new output)
65    pub auto_scroll: bool,
66
67    // --- TMU Phase 1: Stateless Core ---
68    /// Agent name for checkpoint/token paths (replaces ABK_AGENT_NAME env var).
69    /// Defaults to "trustee". Set from config at startup.
70    pub agent_name: String,
71    /// Per-session token store (None = FileTokenStore fallback).
72    /// When set, MCP credential flows use this instead of file-based storage.
73    pub token_store: Option<Arc<dyn pep::token_store::TokenStore>>,
74
75    // --- Project/Session Identity (backward compatible, all None = old behavior) ---
76    /// Storage partition key (replaces path hash). None = hash(working_dir)
77    pub project_id: Option<String>,
78    /// Human-readable project name. None = directory name
79    pub project_name: Option<String>,
80    /// Storage directory name (replaces timestamp slug). None = auto-generate
81    pub session_id: Option<String>,
82    /// Human-readable session name. None = no description
83    pub session_name: Option<String>,
84    /// Per-user home directory for checkpoint storage. None = default ~/.{agent_name}/
85    /// Set to ~/.trustee/users/{user_hash}/ for per-user isolation in web mode.
86    pub home_dir: Option<std::path::PathBuf>,
87
88    /// Concurrency permit — held while a workflow is running.
89    /// When the workflow completes (state → Idle), this is dropped,
90    /// releasing the permit back to the global semaphore.
91    /// None when no workflow is running or when concurrency limiting is disabled.
92    pub workflow_permit: Option<tokio::sync::OwnedSemaphorePermit>,
93}
94
95impl Session {
96    /// Create a new Session with default state and a fresh message channel.
97    ///
98    /// Returns `(Session, Receiver)` so the caller can own the receiver
99    /// without locking the session (prevents deadlock in async drain loops).
100    pub fn new() -> (Self, mpsc::UnboundedReceiver<TuiMessage>) {
101        let (workflow_tx, workflow_rx) = mpsc::unbounded_channel();
102        let session = Self {
103            input: String::new(),
104            output_lines: Vec::new(),
105            workflow_tx,
106            workflow_state: WorkflowState::Idle,
107            config_toml: None,
108            secrets: None,
109            build_info: None,
110            resume_info: None,
111            backup_resume_info: None,
112            todo_lines: Vec::new(),
113            cancel_token: CancellationToken::new(),
114            pending_command: None,
115            handoff_pending: false,
116            pending_tool_lines: Vec::new(),
117            current_context_tokens: 0,
118            auto_handoff: AutoHandoffConfig::default(),
119            mcp_servers: Vec::new(),
120            should_quit: false,
121            auto_scroll: true,
122            agent_name: "trustee".to_string(),
123            token_store: None,
124            project_id: None,
125            project_name: None,
126            session_id: None,
127            session_name: None,
128            home_dir: None,
129            workflow_permit: None,
130        };
131        (session, workflow_rx)
132    }
133
134    /// Parse auto-handoff configuration from the stored config TOML.
135    pub fn parse_auto_handoff_config(&mut self) {
136        if let Some(ref config_toml) = self.config_toml {
137            self.auto_handoff = crate::config::parse_auto_handoff_config(config_toml);
138        }
139    }
140
141    /// Handle messages from async workflows.
142    ///
143    /// This processes all workflow lifecycle events, output updates, and state transitions.
144    /// Returns `true` if the caller should check for pending commands/handoffs after.
145    pub fn handle_workflow_message(&mut self, msg: TuiMessage) {
146        match msg {
147            TuiMessage::WorkflowCancelled => {
148                self.output_lines.push("⏹ Workflow cancelled".to_string());
149                self.output_lines.push("".to_string());
150                self.workflow_state = WorkflowState::Cancelling;
151            }
152            TuiMessage::OutputLine(line) => {
153                self.output_lines.push(line);
154            }
155            TuiMessage::StreamDelta(delta) => {
156                if let Some(last) = self.output_lines.last_mut() {
157                    last.push_str(&delta);
158                } else {
159                    self.output_lines.push(delta);
160                }
161            }
162            TuiMessage::ReasoningDelta(delta) => {
163                if let Some(last) = self.output_lines.last_mut() {
164                    if !last.starts_with('\x01') {
165                        last.insert(0, '\x01');
166                    }
167                    last.push_str(&delta);
168                } else {
169                    self.output_lines.push(format!("\x01{}", delta));
170                }
171            }
172            TuiMessage::WorkflowCompleted => {
173                self.output_lines.push("✓ Workflow completed".to_string());
174                self.output_lines.push("".to_string());
175                if self.workflow_state == WorkflowState::Running {
176                    self.workflow_state = WorkflowState::Cancelling;
177                }
178            }
179            TuiMessage::WorkflowError(err) => {
180                self.output_lines.push(format!("✗ Error: {}", err));
181                self.output_lines.push("".to_string());
182                if self.workflow_state == WorkflowState::Running {
183                    self.workflow_state = WorkflowState::Cancelling;
184                }
185            }
186            TuiMessage::TodoUpdate(content) => {
187                self.todo_lines = content.lines().map(|l| l.to_string()).collect();
188            }
189            TuiMessage::ToolPending { tool_name, hint } => {
190                let label = match &hint {
191                    Some(h) => format!("⠋ {} {}", tool_name, h),
192                    None => format!("⠋ {}", tool_name),
193                };
194                let idx = self.output_lines.len();
195                self.output_lines.push(label);
196                self.pending_tool_lines.push((tool_name, idx, hint));
197            }
198            TuiMessage::ToolDone { tool_name, success, hint } => {
199                let status = if success { "✓" } else { "✗" };
200                if let Some(pos) = self.pending_tool_lines.iter().position(|(n, _, _)| *n == tool_name) {
201                    let (_, idx, pending_hint) = self.pending_tool_lines.remove(pos);
202                    let h = hint.or(pending_hint);
203                    let label = match &h {
204                        Some(h) => format!("{} {} {}", status, tool_name, h),
205                        None => format!("{} {}", status, tool_name),
206                    };
207                    if idx < self.output_lines.len() {
208                        self.output_lines[idx] = label;
209                        return;
210                    }
211                    self.output_lines.push(label);
212                } else {
213                    let label = match &hint {
214                        Some(h) => format!("{} {} {}", status, tool_name, h),
215                        None => format!("{} {}", status, tool_name),
216                    };
217                    self.output_lines.push(label);
218                }
219            }
220            TuiMessage::ResumeInfo(info) => {
221                if self.workflow_state == WorkflowState::Cancelling && info.is_none() {
222                    self.resume_info = self.backup_resume_info.take();
223                } else if info.is_some() {
224                    // Only overwrite with a valid resume_info.
225                    // Don't let ResumeInfo(None) clobber a valid Some that was
226                    // set by an earlier incremental checkpoint message — this
227                    // happens when the error/cancel path fails to create a
228                    // final checkpoint but earlier checkpoints exist.
229                    self.resume_info = info;
230                    self.backup_resume_info = None;
231                }
232                // If info is None and we're not cancelling, keep existing resume_info.
233
234                // Capture session_id from resume_info so it persists for the
235                // lifetime of this conversation. This is immutable — once ABK
236                // assigns it, we never change it.
237                if let Some(ref ri) = self.resume_info {
238                    if self.session_id.is_none() {
239                        self.session_id = Some(ri.session_id.clone());
240                    }
241                }
242
243                if self.workflow_state == WorkflowState::Cancelling {
244                    self.workflow_state = WorkflowState::Idle;
245                    // Release the concurrency permit when the workflow finishes.
246                    self.workflow_permit = None;
247                }
248                if self.resume_info.is_some() {
249                    if std::env::var("RUST_LOG")
250                        .map(|v| v.to_lowercase().contains("debug"))
251                        .unwrap_or(false)
252                    {
253                        self.output_lines.push("🔄 Session preserved — next command will continue this session".to_string());
254                    }
255                }
256                if self.workflow_state == WorkflowState::Idle && self.handoff_pending {
257                    self.handoff_pending = false;
258                    self.trigger_handoff(String::new());
259                } else if let Some(cmd) = self.pending_command.take() {
260                    self.input = cmd;
261                    self.execute_command();
262                }
263            }
264            TuiMessage::ContextTokensUpdated(count) => {
265                self.current_context_tokens = count;
266                if self.auto_handoff.enabled
267                    && count >= self.auto_handoff.context_threshold
268                    && self.workflow_state == WorkflowState::Running
269                    && !self.handoff_pending
270                    && self.resume_info.is_some()
271                {
272                    self.handoff_pending = true;
273                    self.cancel_token.cancel();
274                    self.workflow_state = WorkflowState::Cancelling;
275                    self.output_lines.push(format!(
276                        "🔄 Auto-handoff: cancelling workflow, context tokens ({}) ≥ threshold ({})",
277                        count, self.auto_handoff.context_threshold
278                    ));
279                }
280            }
281            TuiMessage::McpServerStatus { name, connected, tool_count, error } => {
282                let status = if connected { McpServerStatus::Connected } else { McpServerStatus::Failed };
283                if let Some(existing) = self.mcp_servers.iter_mut().find(|s| s.name == name) {
284                    existing.status = status;
285                    existing.tool_count = tool_count;
286                    existing.error = error;
287                } else {
288                    self.mcp_servers.push(McpServerInfo { name, status, tool_count, error });
289                }
290            }
291            TuiMessage::HandoffReady(briefing) => {
292                self.workflow_state = WorkflowState::Idle;
293                self.resume_info = None;
294                // Clear session identity so execute_command generates fresh
295                // session_id/session_name for the new post-handoff session.
296                self.session_id = None;
297                self.session_name = None;
298                self.input = briefing;
299                self.execute_command();
300            }
301            TuiMessage::SessionTitleUpdated(title) => {
302                // LLM-generated title has arrived — update the session name.
303                self.session_name = Some(title);
304            }
305        }
306        if self.auto_scroll {
307            // Signal to frontend that it should scroll to bottom.
308            // Frontend reads auto_scroll flag directly.
309        }
310    }
311
312    /// Execute the current command in the input buffer.
313    ///
314    /// Spawns an async ABK workflow task, clears the input buffer, and sets
315    /// workflow_state to Running.
316    pub fn execute_command(&mut self) {
317        let command = self.input.trim().to_string();
318
319        if self.workflow_state != WorkflowState::Idle {
320            self.pending_command = Some(command);
321            self.output_lines.push("⏳ Previous workflow finishing — command queued".to_string());
322            self.input.clear();
323            return;
324        }
325
326        let is_continuation = self.resume_info.is_some();
327
328        if !is_continuation {
329            self.output_lines.clear();
330            // Auto-derive session_id and session_name from the first command
331            // if not explicitly set. The session_id uses timestamp + UUID suffix
332            // (session_YYYY_MM_DD_HH_MM_{uuid8}) for uniqueness across all
333            // interfaces. The session_name is a human-readable display name
334            // (truncated command text).
335            if self.session_id.is_none() {
336                let timestamp = chrono::Utc::now().format("%Y_%m_%d_%H_%M");
337                let uuid_suffix = uuid::Uuid::new_v4().simple().to_string();
338                let uuid8 = &uuid_suffix[..8];
339                self.session_id = Some(format!("session_{}_{}", timestamp, uuid8));
340            }
341            if self.session_name.is_none() {
342                let derived = if command.len() > 80 {
343                    format!("{}...", &command[..77])
344                } else {
345                    command.clone()
346                };
347                self.session_name = Some(derived);
348            }
349        }
350
351        self.output_lines.push(format!("> {}", command));
352
353        let config_toml = match &self.config_toml {
354            Some(c) => c.clone(),
355            None => {
356                self.output_lines.push("✗ Error: Configuration not loaded".to_string());
357                self.output_lines.push("".to_string());
358                return;
359            }
360        };
361
362        let secrets = self.secrets.clone().unwrap_or_default();
363        // Clone secrets for post-completion title generation (secrets are moved into run_task below)
364        let title_secrets = secrets.clone();
365        let build_info = self.build_info.clone();
366        let tx = self.workflow_tx.clone();
367
368        let agent_name = self.agent_name.clone();
369        let token_store = self.token_store.clone();
370        let project_id = self.project_id.clone();
371        let project_name = self.project_name.clone();
372        let session_id = self.session_id.clone();
373        let session_name = self.session_name.clone();
374        let home_dir = self.home_dir.clone();
375
376        self.backup_resume_info = self.resume_info.clone();
377        let resume_info = self.resume_info.take();
378
379        self.workflow_state = WorkflowState::Running;
380        self.auto_scroll = true;
381
382        self.cancel_token = CancellationToken::new();
383        let child_token = self.cancel_token.clone();
384
385        let (resume_tx, mut resume_rx) = mpsc::unbounded_channel();
386
387        let resume_forward_tx = tx.clone();
388        tokio::spawn(async move {
389            while let Some(info) = resume_rx.recv().await {
390                resume_forward_tx.send(TuiMessage::ResumeInfo(info)).ok();
391            }
392        });
393
394        tokio::spawn(async move {
395            let tui_sink: abk::orchestration::output::SharedSink =
396                Arc::new(crate::session::TuiForwardSink::new(tx.clone()));
397
398            // Build RunContext from session fields for stateless operation
399            let mut run_ctx = RunContext::new()
400                .with_agent_name(agent_name.clone());
401
402            // Set home_dir for per-user isolation if provided
403            if let Some(ref dir) = home_dir {
404                run_ctx = run_ctx.with_home_dir(dir.clone());
405            }
406
407            // Set project identity if any field is provided
408            if project_id.is_some() || project_name.is_some() {
409                run_ctx = run_ctx.with_project(abk::context::ProjectIdentity {
410                    id: project_id.unwrap_or_else(|| "default".to_string()),
411                    name: project_name,
412                });
413            }
414
415            // Set session identity if any field is provided
416            if session_id.is_some() || session_name.is_some() {
417                run_ctx = run_ctx.with_session(abk::context::SessionIdentity {
418                    id: session_id.unwrap_or_else(|| "default".to_string()),
419                    name: session_name,
420                });
421            }
422
423            #[cfg(feature = "registry-mcp-token")]
424            {
425                if let Some(ref ts) = token_store {
426                    run_ctx = run_ctx.with_token_store(ts.clone());
427                }
428            }
429
430            // Run the entire workflow inside a TUI-mode scope and a
431            // per-task logger scope. This replaces the old process-global
432            // set_tui_mode()/init_global_logger() mutations with task-local
433            // scopes, enabling safe concurrent multi-user operation.
434            let scope_logger = {
435                abk::observability::Logger::with_agent_name(
436                    None::<&std::path::Path>,
437                    Some("INFO"),
438                    Some(&agent_name),
439                ).unwrap_or_else(|_| abk::observability::Logger::new(None, Some("INFO")).unwrap())
440            };
441
442            let result = abk::observability::with_logger(scope_logger, async {
443                abk::observability::with_tui_mode(true, async {
444                    abk::cli::run_task_from_raw_config(
445                        &config_toml,
446                        secrets,
447                        build_info,
448                        &command,
449                        Some(tui_sink),
450                        resume_info,
451                        Some(resume_tx),
452                        Some(child_token),
453                        Some(&run_ctx),
454                    )
455                    .await
456                })
457                .await
458            })
459            .await;
460
461            let task_result = result.unwrap_or_else(|e| abk::cli::TaskResult {
462                success: false,
463                error: Some(e.to_string()),
464                // resume_info will be None here, but the on_checkpoint channel
465                // may have already delivered a valid ResumeInfo via TuiMessage.
466                // The ResumeInfo handler now ignores None when a valid Some exists,
467                // so this None won't clobber the earlier incremental checkpoint.
468                resume_info: None,
469            });
470
471            let msg = if task_result.success {
472                TuiMessage::WorkflowCompleted
473            } else {
474                TuiMessage::WorkflowError(task_result.error.unwrap_or_default())
475            };
476
477            // Capture session_id from resume_info before it's moved into the channel
478            let title_session_id = task_result.resume_info
479                .as_ref()
480                .map(|ri| ri.session_id.clone());
481
482            tx.send(msg).ok();
483            tx.send(TuiMessage::ResumeInfo(task_result.resume_info)).ok();
484
485            // Solution B: After successful completion, spawn a lightweight LLM call
486            // to generate a descriptive session title. The title is:
487            // 1. Sent via SessionTitleUpdated message (updates in-memory session_name)
488            // 2. Persisted to session_metadata.json on disk via persist_session_title
489            // Fire-and-forget — errors don't affect the session.
490            if task_result.success {
491                let title_tx = tx.clone();
492                let title_config = config_toml.clone();
493                let title_command = command.clone();
494                let title_ctx = run_ctx.clone();
495
496                tokio::spawn(async move {
497                    match abk::cli::generate_session_title(
498                        &title_config,
499                        title_secrets,
500                        &title_command,
501                    )
502                    .await
503                    {
504                        Ok(Some(title)) => {
505                            // Persist to disk so the title survives session list/reload
506                            if let Some(ref sid) = title_session_id {
507                                if let Err(e) = abk::cli::persist_session_title(
508                                    &title_ctx,
509                                    sid,
510                                    &title,
511                                ).await {
512                                    let _ = e; // non-fatal
513                                }
514                            }
515                            // Update in-memory session name for live WS clients
516                            title_tx.send(TuiMessage::SessionTitleUpdated(title)).ok();
517                        }
518                        Ok(None) => {
519                            // Empty title — keep the default truncated-command title
520                        }
521                        Err(e) => {
522                            // Non-fatal: keep the default truncated-command title
523                            let _ = e;
524                        }
525                    }
526                });
527            }
528        });
529
530        self.input.clear();
531    }
532
533    /// Trigger a session handoff.
534    ///
535    /// Runs a single LLM call using the current session's resume_info to generate
536    /// a briefing. On completion, sends `TuiMessage::HandoffReady(briefing)`.
537    pub fn trigger_handoff(&mut self, hint: String) {
538        if self.resume_info.is_none() {
539            self.output_lines.push("ℹ Nothing to hand off — run a task first".to_string());
540            return;
541        }
542
543        let config_toml = match &self.config_toml {
544            Some(c) => c.clone(),
545            None => {
546                self.output_lines.push("✗ Error: Configuration not loaded".to_string());
547                return;
548            }
549        };
550
551        let secrets = self.secrets.clone().unwrap_or_default();
552        let build_info = self.build_info.clone();
553        let tx = self.workflow_tx.clone();
554
555        let agent_name = self.agent_name.clone();
556        let token_store = self.token_store.clone();
557        let project_id = self.project_id.clone();
558        let project_name = self.project_name.clone();
559        let session_id = self.session_id.clone();
560        let session_name = self.session_name.clone();
561        let home_dir = self.home_dir.clone();
562
563        let resume_info = self.resume_info.take();
564
565        self.workflow_state = WorkflowState::Running;
566        self.auto_scroll = true;
567        self.cancel_token = CancellationToken::new();
568        let child_token = self.cancel_token.clone();
569
570        self.output_lines.push("🔀 Generating session handoff briefing...".to_string());
571
572        tokio::spawn(async move {
573            let (cap_tx, mut cap_rx) = mpsc::unbounded_channel::<CapturedText>();
574            let cap_sink: abk::orchestration::output::SharedSink =
575                Arc::new(HandoffCaptureSink::new(cap_tx, child_token.clone()));
576
577            let base = "Output a session handoff briefing in at most 300 lines. \
578                 Do NOT use any tools. Include: the FULL ABSOLUTE PATH of every \
579                 project/repository being worked on (e.g. /Projects/Foo/bar — never \
580                 omit the leading path), all project/task/workstream UUIDs referenced, \
581                 every file created or modified with its full absolute path, all \
582                 commands run and their outcomes, the current state of the work, any \
583                 blockers, and the exact next action to take. \
584                 Output ONLY the briefing text — no preamble, headers, or closing remarks.";
585            let prompt = if hint.is_empty() {
586                base.to_string()
587            } else {
588                format!("{base}\n\nIn the briefing also consider: {hint}")
589            };
590
591            let (dummy_tx, _dummy_rx) = mpsc::unbounded_channel();
592
593            // Build RunContext for stateless operation — same fields as execute_command
594            let mut run_ctx = RunContext::new()
595                .with_agent_name(agent_name.clone());
596
597            // Set home_dir for per-user isolation
598            if let Some(ref dir) = home_dir {
599                run_ctx = run_ctx.with_home_dir(dir.clone());
600            }
601
602            // Set project identity if any field is provided
603            if project_id.is_some() || project_name.is_some() {
604                run_ctx = run_ctx.with_project(abk::context::ProjectIdentity {
605                    id: project_id.unwrap_or_else(|| "default".to_string()),
606                    name: project_name,
607                });
608            }
609
610            // Set session identity if any field is provided
611            if session_id.is_some() || session_name.is_some() {
612                run_ctx = run_ctx.with_session(abk::context::SessionIdentity {
613                    id: session_id.unwrap_or_else(|| "default".to_string()),
614                    name: session_name,
615                });
616            }
617            #[cfg(feature = "registry-mcp-token")]
618            {
619                // Note: token_store not available in handoff — handoffs don't
620                // need MCP credentials, so we skip it here.
621            }
622
623            // Run inside per-task logger + TUI-mode scope (task-local, not process-global)
624            let scope_logger = abk::observability::Logger::with_agent_name(
625                None,
626                Some("INFO"),
627                Some(&agent_name),
628            ).unwrap_or_else(|_| abk::observability::Logger::new(None, Some("INFO")).unwrap());
629
630            let _res = abk::observability::with_logger(scope_logger, async {
631                abk::observability::with_tui_mode(true, async {
632                    abk::cli::run_task_from_raw_config(
633                        &config_toml,
634                        secrets,
635                        build_info,
636                        &prompt,
637                        Some(cap_sink),
638                        resume_info,
639                        Some(dummy_tx),
640                        Some(child_token),
641                        Some(&run_ctx),
642                    )
643                    .await
644                })
645                .await
646            })
647            .await;
648
649            let mut text_parts = String::new();
650            let mut reasoning_parts = String::new();
651            while let Ok(captured) = cap_rx.try_recv() {
652                match captured {
653                    CapturedText::Text(s) => text_parts.push_str(&s),
654                    CapturedText::Reasoning(s) => reasoning_parts.push_str(&s),
655                }
656            }
657
658            let briefing = if !text_parts.trim().is_empty() {
659                text_parts.trim().to_string()
660            } else if !reasoning_parts.trim().is_empty() {
661                reasoning_parts.trim().to_string()
662            } else {
663                "Session handoff: briefing unavailable — continue from previous context.".to_string()
664            };
665
666            tx.send(TuiMessage::HandoffReady(briefing)).ok();
667        });
668    }
669}
670
671impl Default for Session {
672    fn default() -> Self {
673        Self::new().0
674    }
675}
676
677/// A sink that forwards ABK `OutputEvent`s to the message channel.
678///
679/// Includes a 3-state atomic state machine (IDLE/REASONING/CONTENT) that
680/// inserts blank separator lines when transitioning between reasoning and
681/// content streams, so the frontend can distinguish them visually.
682pub struct TuiForwardSink {
683    tx: mpsc::UnboundedSender<TuiMessage>,
684    stream_state: AtomicU8,
685}
686
687/// Stream state machine constants.
688const STREAM_IDLE: u8 = 0;
689const STREAM_REASONING: u8 = 1;
690const STREAM_CONTENT: u8 = 2;
691
692impl TuiForwardSink {
693    pub fn new(tx: mpsc::UnboundedSender<TuiMessage>) -> Self {
694        Self {
695            tx,
696            stream_state: AtomicU8::new(STREAM_IDLE),
697        }
698    }
699}
700
701impl abk::orchestration::output::OutputSink for TuiForwardSink {
702    fn emit(&self, event: abk::orchestration::output::OutputEvent) {
703        use abk::orchestration::output::OutputEvent;
704
705        let msg = match event {
706            OutputEvent::StreamingChunk { delta } => {
707                if delta.is_empty() {
708                    return;
709                }
710                let prev = self.stream_state.swap(STREAM_CONTENT, Ordering::Relaxed);
711                if prev != STREAM_CONTENT {
712                    let _ = self.tx.send(TuiMessage::OutputLine(String::new()));
713                }
714                let _ = self.tx.send(TuiMessage::StreamDelta(delta));
715                return;
716            }
717
718            OutputEvent::LlmResponse { text, model } => {
719                TuiMessage::OutputLine(format!("[{}] {}", model, text))
720            }
721
722            OutputEvent::Info { message } => {
723                // Suppress noisy/no-value messages from ABK
724                if message.contains("API call completed successfully") {
725                    return;
726                }
727                TuiMessage::OutputLine(message)
728            }
729
730            OutputEvent::WorkflowStarted { task_description } => {
731                TuiMessage::OutputLine(format!("🚀 Workflow started: {}", task_description))
732            }
733
734            OutputEvent::WorkflowCompleted { reason, iterations } => {
735                TuiMessage::OutputLine(format!(
736                    "✅ Workflow completed after {} iterations: {}",
737                    iterations, reason
738                ))
739            }
740
741            OutputEvent::IterationStarted { iteration, context_tokens } => {
742                let _ = self.tx.send(TuiMessage::ContextTokensUpdated(context_tokens));
743                TuiMessage::OutputLine(format!(
744                    "📡 Iteration {} | Context = {} tokens",
745                    iteration, context_tokens
746                ))
747            }
748
749            OutputEvent::ApiCallStarted {
750                call_number,
751                model,
752                tool_count,
753                streaming,
754                context_tokens,
755                tool_tokens,
756            } => {
757                let mode = if streaming { "Streaming" } else { "Non-streaming" };
758                let total = context_tokens + tool_tokens;
759                let _ = self.tx.send(TuiMessage::ContextTokensUpdated(total));
760                // Blank line separator before each API call for readability
761                let _ = self.tx.send(TuiMessage::OutputLine(String::new()));
762                TuiMessage::OutputLine(format!(
763                    "🔥 API Call {} | Ctx={}({}+{}) | {} | Model: {} | Tools: {}",
764                    call_number, total, context_tokens, tool_tokens, mode, model, tool_count
765                ))
766            }
767
768            OutputEvent::ToolsExecuting { tool_names, hints } => {
769                for (name, hint) in tool_names.into_iter().zip(hints.into_iter()) {
770                    let _ = self.tx.send(TuiMessage::ToolPending { tool_name: name, hint });
771                }
772                self.stream_state.store(STREAM_IDLE, Ordering::Relaxed);
773                return;
774            }
775
776            OutputEvent::ToolCompleted {
777                tool_name,
778                success,
779                content,
780                description,
781            } => {
782                if tool_name == "todowrite" && success {
783                    let _ = self.tx.send(TuiMessage::TodoUpdate(content.clone()));
784                }
785                let hint = description;
786                let _ = self.tx.send(TuiMessage::ToolDone { tool_name, success, hint });
787                self.stream_state.store(STREAM_IDLE, Ordering::Relaxed);
788                return;
789            }
790
791            OutputEvent::Error { message, context } => {
792                if let Some(ctx) = context {
793                    TuiMessage::OutputLine(format!("❌ Error: {} — {}", message, ctx))
794                } else {
795                    TuiMessage::OutputLine(format!("❌ Error: {}", message))
796                }
797            }
798
799            OutputEvent::ReasoningChunk { delta } => {
800                if delta.is_empty() {
801                    return;
802                }
803                let prev = self.stream_state.swap(STREAM_REASONING, Ordering::Relaxed);
804                if prev != STREAM_REASONING {
805                    let _ = self.tx.send(TuiMessage::OutputLine(String::new()));
806                }
807                let _ = self.tx.send(TuiMessage::ReasoningDelta(delta));
808                return;
809            }
810
811            OutputEvent::McpServerStatus { name, connected, tool_count, error } => {
812                let _ = self.tx.send(TuiMessage::McpServerStatus {
813                    name,
814                    connected,
815                    tool_count,
816                    error,
817                });
818                return;
819            }
820        };
821
822        self.stream_state.store(STREAM_IDLE, Ordering::Relaxed);
823        let _ = self.tx.send(msg);
824    }
825}