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+# Daily Timer - AI Assistant Instructions
+
+## Project Overview
+
+- **Purpose**: Desktop meeting timer application with speaker management
+- **Framework**: Wails v2.11.0 (Go backend + Svelte frontend)
+- **Status**: Active development
+
+## Technology Stack
+
+| Component     | Technology                  |
+| ------------- | --------------------------- |
+| **Backend**   | Go 1.21+                    |
+| **Framework** | Wails v2.11.0               |
+| **Frontend**  | Svelte 4 + Vite             |
+| **Database**  | SQLite via GORM             |
+| **Audio**     | Web Audio API (oscillators) |
+| **Linter**    | golangci-lint               |
+
+## Project Structure
+
+```
+daily-timer/
+├── main.go                    # App entry point
+├── wails.json                 # Wails configuration
+├── internal/
+│   ├── app/
+│   │   └── app.go             # Main App struct, Wails bindings
+│   ├── models/
+│   │   └── models.go          # Data models (Participant, Meeting, etc.)
+│   ├── storage/
+│   │   └── storage.go         # GORM database operations
+│   └── timer/
+│       └── timer.go           # Timer logic, event emission
+├── frontend/
+│   ├── src/
+│   │   ├── App.svelte         # Main component, event handlers
+│   │   ├── components/
+│   │   │   ├── Timer.svelte
+│   │   │   ├── ParticipantList.svelte
+│   │   │   ├── Controls.svelte
+│   │   │   ├── Settings.svelte
+│   │   │   ├── History.svelte
+│   │   │   └── Setup.svelte
+│   │   └── lib/
+│   │       └── i18n.js        # Translations (RU/EN)
+│   └── wailsjs/               # Auto-generated Go bindings
+└── build/                     # Build output
+```
+
+## Critical Rules - MUST FOLLOW
+
+### 1. Wails Terminal Directory
+
+**ALWAYS run `wails dev` from project root**, not from subdirectories:
+
+```bash
+# ✅ CORRECT
+cd /Users/admin-msk/git/daily-timer && wails dev
+
+# ❌ WRONG - causes "wails.json not found" error
+cd /Users/admin-msk/git/daily-timer/internal/timer && wails dev
+```
+
+### 2. TypeScript Model Casing
+
+Go structs use PascalCase, but Wails generates TypeScript with camelCase:
+
+```go
+// Go model
+type Session struct {
+    ID        uint
+    StartTime time.Time
+}
+```
+
+```typescript
+// Generated TypeScript - use lowercase!
+session.id; // ✅ CORRECT
+session.ID; // ❌ WRONG - undefined
+session.startTime; // ✅ CORRECT
+session.StartTime; // ❌ WRONG - undefined
+```
+
+### 3. GORM Partial Updates
+
+**NEVER use `db.Save()` for partial updates** - it overwrites ALL fields with zero values:
+
+```go
+// ❌ WRONG - overwrites Active, Order, etc. with zero values
+func (s *Storage) UpdateParticipant(p *models.Participant) error {
+    return s.db.Save(p).Error
+}
+
+// ✅ CORRECT - updates only specified fields
+func (s *Storage) UpdateParticipant(p *models.Participant) error {
+    return s.db.Model(p).Updates(map[string]interface{}{
+        "name":       p.Name,
+        "email":      p.Email,
+        "time_limit": p.TimeLimit,
+    }).Error
+}
+```
+
+### 4. Timer Event Flags
+
+Use separate flags for different event types to prevent blocking:
+
+```go
+// ❌ WRONG - one flag blocks both events
+speakerWarned bool  // After warning, timeup never fires
+
+// ✅ CORRECT - separate flags
+speakerWarned        bool  // For warning event
+speakerTimeUpEmitted bool  // For timeup event
+```
+
+### 5. Sound in Wails (macOS)
+
+- Use Web Audio API oscillators, not audio files
+- macOS "Do Not Disturb" mode blocks sounds
+- Always add test buttons in Settings for verification
+
+```javascript
+function playBeep(frequency, duration) {
+  const ctx = new AudioContext();
+  const osc = ctx.createOscillator();
+  const gain = ctx.createGain();
+  osc.connect(gain);
+  gain.connect(ctx.destination);
+  osc.frequency.value = frequency;
+  gain.gain.setValueAtTime(0.3, ctx.currentTime);
+  gain.gain.exponentialRampToValueAtTime(0.01, ctx.currentTime + duration);
+  osc.start();
+  osc.stop(ctx.currentTime + duration);
+}
+```
+
+### 6. Svelte Event Dispatching
+
+When adding interactivity to list items:
+
+```svelte
+<!-- Parent component -->
+<ChildList on:customEvent={handleEvent} />
+
+<!-- Child component -->
+<script>
+  import { createEventDispatcher } from 'svelte'
+  const dispatch = createEventDispatcher()
+
+  function handleClick(id) {
+    dispatch('customEvent', { id })
+  }
+</script>
+```
+
+### 7. i18n Translations
+
+Always update BOTH languages (RU and EN) in `frontend/src/lib/i18n.js`:
+
+```javascript
+translations: {
+  ru: {
+    history: {
+      deleteAll: 'Удалить историю',
+    }
+  },
+  en: {
+    history: {
+      deleteAll: 'Delete History',
+    }
+  }
+}
+```
+
+### 8. Go Linter (golangci-lint)
+
+Run before committing:
+
+```bash
+/opt/homebrew/bin/golangci-lint run ./...
+```
+
+Common fixes:
+
+- Remove explicit types when inferring: `idx := -1` not `var idx int = -1`
+- Remove unused functions
+- Handle all error returns
+
+## Common Bugs & Solutions
+
+| Bug                     | Cause                       | Solution                              |
+| ----------------------- | --------------------------- | ------------------------------------- |
+| `wails.json not found`  | Wrong directory             | Run from project root                 |
+| Data disappears on edit | `db.Save()` overwrites      | Use `Updates(map[string]interface{})` |
+| Event never fires       | Shared flag blocks          | Use separate flags per event          |
+| Sounds don't play       | DND mode or no AudioContext | Add test buttons, check DND           |
+| `undefined` in template | Wrong case (ID vs id)       | Check generated TS types              |
+| Drag-drop doesn't save  | Missing backend call        | Call `ReorderParticipants()`          |
+| "App is damaged" error  | macOS Gatekeeper            | Run `xattr -cr "Daily Timer.app"`     |
+
+## Development Commands
+
+```bash
+# Run in development mode (ALWAYS run manually from clean shell!)
+cd /Users/admin-msk/git/daily-timer && wails dev
+
+# Build for production
+wails build
+
+# Run linter
+/opt/homebrew/bin/golangci-lint run ./...
+
+# Generate bindings (automatic in wails dev)
+wails generate module
+```
+
+## Release Workflow
+
+### Building Release
+
+```bash
+# Build and package for current architecture
+make release
+
+# Build for all macOS architectures (arm64 + amd64)
+make release-all
+```
+
+Output: `dist/Daily-Timer-vX.X.X-macos-arm64.zip`
+
+### Publishing Release to Gitea
+
+```bash
+# Create and push tag
+git tag -a v0.2.0 -m "Release description"
+git push origin v0.2.0
+
+# Build and upload to Gitea (requires GITEA_TOKEN)
+GITEA_TOKEN=your_token make release-publish
+```
+
+### macOS Gatekeeper Fix
+
+**IMPORTANT**: Built app is not signed. macOS shows "app is damaged" error.
+
+Fix for users after downloading:
+
+```bash
+xattr -cr "Daily Timer.app"
+```
+
+Or: Right-click → Open → Open (first launch only)
+
+For apps in /Applications:
+
+```bash
+xattr -cr "/Applications/Daily Timer.app"
+```
+
+## Event System
+
+Timer emits events via Wails runtime:
+
+- `timer:tick` - Every 100ms during active timer
+- `timer:speaker_warning` - When speaker time is running low
+- `timer:speaker_timeup` - When speaker time expired
+- `timer:meeting_warning` - When meeting time running low
+- `timer:meeting_ended` - When meeting ends
+- `timer:speaker_changed` - When switching speakers
+
+Frontend listens in App.svelte:
+
+```javascript
+EventsOn('timer:speaker_warning', handleWarning);
+```
+
+## Debugging
+
+Open DevTools in Wails app: `Cmd+Option+I`
+
+Add console.log for event debugging:
+
+```javascript
+function handleWarning(state) {
+  console.log('=== handleWarning EVENT RECEIVED ===');
+  console.log('settings:', settings);
+  // ...
+}
+```
+
+---
+
+**Last Updated**: February 2026