BTerminal/docs/progress.md

BTerminal v2 — Progress Log

Session: 2026-03-05

Research Phase (complete)

• Analyzed current BTerminal v1 codebase (2092 lines Python, GTK3+VTE)
• Queried Memora — no existing BTerminal memories
• Researched Claude Agent SDK — found structured streaming, subagent tracking, hooks
• Researched Tauri + xterm.js ecosystem — found 4+ working projects
• Researched terminal latency benchmarks — xterm.js acceptable for AI output
• Researched 32:9 ultrawide layout patterns
• Evaluated GTK4 vs Tauri vs pure Rust — Tauri wins for this use case
• Created task_plan.md with 8 phases
• Created findings.md with 7 research areas

Technology Decision (complete)

• Decision: Tauri 2.x + Solid.js + Claude Agent SDK + xterm.js
• Rationale documented in task_plan.md Phase 0

Adversarial Review (complete)

• Spawned devil's advocate agent to attack the plan
• Identified 5 fatal/critical issues:
  1. Node.js sidecar requirement unacknowledged
  2. SDK 0.2.x instability — need abstraction layer
  3. Three-tier observation overengineered → simplified to two-tier
  4. Solid.js ecosystem too small → switched to Svelte 5
  5. Missing: packaging, error handling, testing, responsive design
• Revised plan (Rev 2) incorporating all corrections
• Added error handling strategy table
• Added testing strategy table
• Defined MVP boundary (Phases 1-4)
• Added responsive layout requirement (1920px degraded mode)

Phase 1 Scaffolding (complete)

• Created feature branch v2-mission-control
• Initialized Tauri 2.x + Svelte 5 project in v2/ directory
• Rust backend stubs: main.rs, lib.rs, pty.rs, sidecar.rs, watcher.rs, session.rs
• Svelte frontend: App.svelte with Catppuccin Mocha CSS variables, component stubs
• Node.js sidecar scaffold: agent-runner.ts with NDJSON communication pattern
• Tauri builds and launches (cargo build --release verified)
• Dev scripts: npm run dev, npm run build, npm run tauri dev/build
• 17 operational rules added to .claude/rules/
• Project meta files: CLAUDE.md, .claude/CLAUDE.md, TODO.md, CHANGELOG.md
• Documentation structure: docs/README.md, task_plan.md, phases.md, findings.md, progress.md

Phase 2: Terminal Pane + Layout (complete)

• Rust PTY backend with portable-pty (PtyManager: spawn, write, resize, kill)
• PTY reader thread emitting Tauri events (pty-data-{id}, pty-exit-{id})
• Tauri commands: pty_spawn, pty_write, pty_resize, pty_kill
• xterm.js terminal pane with Canvas addon (explicit, no WebGL)
• Catppuccin Mocha theme for xterm.js (16 ANSI colors)
• FitAddon with ResizeObserver + 100ms debounce
• PTY bridge adapter (spawnPty, writePty, resizePty, killPty, onPtyData, onPtyExit)
• CSS Grid tiling layout with 5 presets (1-col, 2-col, 3-col, 2x2, master-stack)
• Layout store with Svelte 5 $state runes and auto-preset selection
• Sidebar with session list, layout preset selector, new terminal button
• Keyboard shortcuts: Ctrl+N new terminal, Ctrl+1-4 focus pane
• PaneContainer with header bar (title, status, close)
• Empty state welcome screen with Ctrl+N hint
• npm dependencies: @xterm/xterm, @xterm/addon-canvas, @xterm/addon-fit
• Cargo dependencies: portable-pty, uuid

Phase 3: Agent SDK Integration (in progress)

• Rust SidecarManager: spawn Node.js, stdio NDJSON, query/stop/shutdown (sidecar.rs, 218 lines)
• Node.js agent-runner: spawns claude -p --output-format stream-json, manages sessions (agent-runner.ts, 176 lines)
• Tauri commands: agent_query, agent_stop, agent_ready in lib.rs
• Sidecar auto-start on app launch
• SDK message adapter: full stream-json parser with 9 typed message types (sdk-messages.ts, 234 lines)
• Agent bridge: Tauri IPC adapter for sidecar communication (agent-bridge.ts, 53 lines)
• Agent dispatcher: routes sidecar events to agent store (agent-dispatcher.ts, 87 lines)
• Agent store: session state with messages, cost tracking (agents.svelte.ts, 91 lines)
• AgentPane component: prompt input, message rendering, stop button, cost display (AgentPane.svelte, 420 lines)
• UI integration: Ctrl+Shift+N for new agent, sidebar agent button, TilingGrid routing

Architecture decision: Uses claude CLI with --output-format stream-json instead of Agent SDK query() API. Avoids SDK npm dependency and version churn while getting identical structured output.

Bug Fix: Svelte 5 Rune File Extensions (2026-03-06)

• Diagnosed blank screen / "rune_outside_svelte" runtime error
• Root cause: store files used .ts extension but contain Svelte 5 $state/$derived runes, which only work in .svelte and .svelte.ts files
• Renamed: layout.ts -> layout.svelte.ts, agents.ts -> agents.svelte.ts, sessions.ts -> sessions.svelte.ts
• Updated all import paths in 5 files to use .svelte suffix (e.g., from './stores/layout.svelte')

Phase 3 Polish (2026-03-06)

• Sidecar crash detection: dispatcher listens for sidecar-exited event, marks running sessions as error
• Restart UI: "Restart Sidecar" button in AgentPane error bar, calls agent_restart command
• Auto-scroll lock: scroll handler disables auto-scroll when user scrolls >50px from bottom, "Scroll to bottom" button appears

Phase 4: Session Management + Markdown Viewer (2026-03-06)

• rusqlite 0.31 (bundled) + dirs 5 + notify 6 added to Cargo.toml
• SessionDb: SQLite with WAL mode, sessions table + layout_state singleton
• Session CRUD: list, save, delete, update_title, touch (7 Tauri commands)
• Frontend session-bridge.ts: typed invoke wrappers for all session/layout commands
• Layout store wired to persistence: addPane/removePane/focusPane/setPreset all persist
• restoreFromDb() on app startup restores panes in layout order
• FileWatcherManager: notify crate watches files, emits Tauri "file-changed" events
• MarkdownPane component: marked.js rendering, Catppuccin-themed styles, live reload
• Sidebar "M" button opens file picker for .md/.markdown/.txt files
• TilingGrid routes markdown pane type to MarkdownPane component

Phase 5: Agent Tree + Polish (2026-03-06, in progress)

• Agent tree visualization (SVG): AgentTree.svelte component with horizontal tree layout, bezier edges, status-colored nodes; agent-tree.ts utility (buildAgentTree, countTreeNodes, subtreeCost)
• Agent tree toggle in AgentPane: collapsible tree view shown when tool_call messages exist
• Global status bar: StatusBar.svelte showing terminal/agent pane counts, active agents with pulse animation, total tokens and cost
• Notification system: notifications.svelte.ts store (notify, dismissNotification, max 5 toasts, 4s auto-dismiss) + ToastContainer.svelte (slide-in animation, color-coded by type)
• Agent dispatcher notifications: toast on agent_stopped (success), agent_error (error), sidecar crash (error), cost result (success with cost/turns)
• Settings dialog: SettingsDialog.svelte modal (default shell, cwd, max panes) with settings-bridge.ts adapter
• Settings backend: settings table (key/value) in session.rs, Tauri commands settings_get/set/list in lib.rs
• Keyboard shortcuts: Ctrl+W close focused pane, Ctrl+, open settings dialog
• CSS grid update: app.css grid-template-rows '1fr' -> '1fr auto' for status bar row
• App.svelte: integrated StatusBar, ToastContainer, SettingsDialog components

Next Steps

• Markdown rendering in agent text messages
• Testing: vitest for sdk-messages adapter, cargo test for sidecar
• Phase 5 remaining: click tree node -> focus pane, subtree cost display, ctx integration
• Phase 6: Packaging + Distribution