Terminal System Architecture

TerminalOS Class

The main terminal controller class manages all terminal operations.

Initialization Flow

sequenceDiagram
    participant User
    participant TerminalOS
    participant xterm
    participant Filesystem
    participant EcmaOS
    participant BootSequence

    User->>TerminalOS: new TerminalOS('terminal')
    TerminalOS->>xterm: Initialize xterm.js
    TerminalOS->>xterm: Load addons (Fit, WebLinks, etc.)
    TerminalOS->>Filesystem: new VirtualFileSystem()
    TerminalOS->>Filesystem: Load Jekyll data
    TerminalOS->>EcmaOS: initEcmaOS() (async)
    TerminalOS->>BootSequence: Start boot animation
    BootSequence->>TerminalOS: Boot complete callback
    TerminalOS->>User: Show welcome, prompt ready

Command Execution Flow

1. User types command
2. handleCommand() parses input
3. Switch statement routes to handler
4. Local app or EcmaOS delegation
5. Output written to terminal
6. Prompt refreshed

State Management

• currentPath: Current working directory
• currentUser: Active user (guest/root)
• isRoot: Root access flag
• commandHistory: Command history array
• sessionStartTime: Uptime calculation

xterm.js Integration

Addons Loaded

• FitAddon: Auto-resize terminal to container
• WebLinksAddon: Clickable URLs
• SearchAddon: Terminal content search (Ctrl+F)
• Unicode11Addon: Enhanced Unicode support
• SerializeAddon: Terminal state serialization
• ImageAddon: Image display support
• WebglAddon/CanvasAddon: High-performance rendering

Terminal Configuration

• Font: Monaco, Menlo, Ubuntu Mono
• Font size: 12px mobile, 14px desktop
• Scrollback: 1000 lines
• Theme: Matrix green (default)

Input Handling

Key Events

• Enter: Execute command
• Backspace: Delete character
• Arrow Up/Down: Command history
• Tab: Command/file completion
• Ctrl+F: Search terminal content

Tab Completion

1. Parse input to get command/argument
2. If command: match against command list
3. If argument: match against filesystem listing
4. Show matches or complete if unique

Boot Sequence

Simulated computer boot process:

1. BIOS: POST checks, hardware detection
2. Boot Loader: GRUB-style interface
3. Kernel: Loading animation
4. Init: Service startup
5. Ready: Welcome message, prompt

Press ESC to skip boot sequence.