Ophanim

ophanim

A terminal that can summon a browser. Tile terminals and web pages in the same window; flip a pane to a browser with browse <url>, flip it back with Alt+Esc. macOS-first. tmux-backed so shells survive quit + relaunch. Session restore brings back the full layout, shells, URLs and back/forward history.

Architecture (90-second tour)

• main.js — Electron main. World → Workspace → Split-tree → Pane model, layout math, IPC, keybinding dispatch, config loading, session restore glue.
• renderer.js — The termView. One xterm.js Terminal instance per terminal pane, custom OSC handler for the browse / config shell helpers, custom wheel handler for alt-buffer apps.
• browser-chrome.html — URL bar / nav chrome that stacks on top of each browser pane.
• config-ui.html — In-app settings pane. Schema-driven — walks the DEFAULT_* objects and renders form rows with live preview + per-field reset.
• tmux-backend.js — tmux as PTY supervisor. Generates ophanim-tmux.conf from config, manages session lifecycle.
• session-store.js — JSON snapshot of window bounds, split tree, pane kinds, browser history, focus, zoom. Round-trips on quit.

Shell spawn path: ophanim → spawnPty → tmux attach client → tmux session → user's shell. Shells live in the tmux daemon (label -L ophanim) so they outlast the Electron process. An external terminal can tmux -L ophanim attach -t <session> and see the same shell.

Browser panes: each is a WebContentsView (page) plus a second WebContentsView (chrome bar) stacked on top of the termView. pane-host divs in the termView have a 1px CSS border that peeks through the 1px inset around the WebContentsViews — that's the focus ring.

Where config lives

At runtime the user has two files in ~/.config/ophanim/:

• defaults.json — auto-rewritten on every launch from the source schema. Contains every setting with its default value and an inline _reference block describing what each one does. Read this file first when the user asks "how do I change X?" or "what keys does ophanim use?" — it's the source of truth for what's configurable right now.
• config.json — user overrides. Only fields that differ from default need to be present; everything else falls back. Edits hot-reload (no relaunch needed).

The in-app config command opens a schema-driven UI for the same file.

In source, all defaults are defined in main.js:

• DEFAULT_BINDINGS — keyboard shortcuts (action → chord strings).
• DEFAULT_TERMINAL — font, theme, shell, tmux path, scroll mode.
• DEFAULT_WINDOW — window size.
• DEFAULT_PANES — pane border colors / width.
• DEFAULT_WORKSPACES — workspace strip colors / wrap.
• DEFAULT_BROWSER — browser chrome + border colors.

Live values in module-level globals: bindings, termConfig, windowConfig, paneConfig, workspaceConfig, browserConfig. Read those at the point of use; never cache copies.

applyParsedConfig (in main.js) is the one place that reassigns the globals + pushes changes to running state (keybindings, themes, tmux conf, window sizes). Hot-reload works automatically if your feature reads the live global.

Config reflex (run this every feature)

Every feature has hardcoded knobs — colors, keys, sizes, timing, thresholds. After finishing a change, audit them and tell the user what you could expose. Don't wait to be asked.

Good candidates: keys, colors, fonts, sizes, timing constants, behavioral toggles, paths to external tools, multipliers and factors, any default where reasonable people disagree.

Not candidates: protocol constants (OSC numbers, IPC channel names), values required for correctness (e.g. 1-pixel pane inset — breaks focus border if changed), values with one obviously-right answer.

How to add a configurable:

1. Add a key to the right DEFAULT_* (nest under a sub-object when grouping — e.g. terminal.scroll.linesPerPress).
2. Read from the live global at point of use.
3. If it's hot-reloadable, ensure applyParsedConfig pushes the change. (The tmux conf, keybinding table, browser themes, and window sizes already do this.)
4. If it needs validation, add a check in validateConfig.
5. That's it — the config UI renders the field automatically from the schema, with live preview and a per-field reset button.

Report format:

Feature X has these hardcoded now. Candidates for config:

• section.fieldA (default ...) — what it controls
• section.fieldB (default ...) — what it controls

Want me to wire any?

Tight, scannable, one line per field. Let the user pick.

Ground rules when extending

• Prefer existing DEFAULT_* buckets over new top-level sections.
• Keep main.js additions narrow — no abstraction without a second user.
• Session restore must round-trip any new pane state.
• tmux is a PTY supervisor here, not a UI. Features needing tmux's own UI (status bar, prefix chords) belong higher up.
• Rebuild with npm run dist after changes; copy dist/mac-arm64/Ophanim.app → /Applications/Ophanim.app to test.