discordo-plus/CLAUDE.md

Project Context

What This File Is

This is the persistent context file for Claude Code. Keep it concise and useful.

CLAUDE.md Maintenance Rules

• Keep this file under 160 lines
• Only record decisions, not explanations of common knowledge
• When adding something, check if anything existing is now outdated and remove it
• Use short bullet points, not paragraphs
• No boilerplate or filler text
• If a section grows past 10 items, consolidate or prune the least relevant ones
• Format: what we chose + why in one line (e.g., "imv over feh — WebP/Wayland support")

Overview

• Fork of ayn2op/discordo — a Discord TUI client
• Upstream: https://github.com/ayn2op/discordo.git
• Our repo: https://gogs.altsol.dev/claude/discordo-plus.git (branch: master)
• Binary name: discordo-plus (installed to /usr/local/bin/)

Stack

• Go (module: github.com/ayn2op/discordo)
• TUI: github.com/ayn2op/tview (custom tview fork) + tcell/v3
• Discord API: arikawa/v3 + ningen/v3 (state management + Discord markdown)
• Markdown: goldmark parser + chroma/v2 syntax highlighting
• Config: TOML via BurntSushi/toml, file at ~/.config/discordo/config.toml
• Cache: ~/.cache/discordo/ (attachments, logs, state)

Architecture

• main.go → cmd/root.go (app init) → internal/ui/ (TUI layers)
• internal/ui/chat/ — core chat UI: messages_list.go (rendering/keybinds), attachment_handler.go, embed_renderer.go, url_extractor.go, message_input.go, guilds_tree.go, attachments_picker.go
• internal/markdown/renderer.go — AST→styled lines, handles Discord markdown flavors
• internal/config/ — config.go (struct + loader), config.toml (defaults, embedded), keybinds.go, theme.go, editor.go
• internal/consts/ — app name, cache dir
• internal/ui/chat/guildstate.go — persists guild + channel expand/collapse state to ~/.cache/discordo/state.json
• Rendering pipeline: messages → tview.LineBuilder → []tview.Line (segments with tcell.Style)
• URLs get style.Url(rawURL) metadata for OSC 8 terminal hyperlinks
• External commands (editor, image viewer) use app.Suspend() pattern — suspends TUI, runs command, resumes

Key Patterns

• Keybinds: defined in config/keybinds.go structs, matched in HandleEvent() via keybind.Matches()
• Help tooltips: ShortHelp() (bottom bar, contextual) and FullHelp() (full overlay via ?)
• Attachments: downloaded to ~/.cache/discordo/attachments/, opened via configured viewer or openDefault()
• Embeds: rendered with ▎ bar prefix, wrapped to viewport width, markdown in descriptions
• Config defaults embedded via //go:embed config.toml

Our Changes (vs upstream)

• Image viewer: image_viewer / image_viewer_args config, save_image keybind (S), mpv geometry auto-detection via xdotool, supported types: jpeg/png/webp/gif
• Attachments: URL fix (proper NewLine() + .Url() style), o in ShortHelp when attachments/URLs present
• Help/Config: ? keybind (was ctrl+.), E edits config in $EDITOR/vim from help overlay
• State persistence: guild + channel expand/collapse state in ~/.cache/discordo/state.json (guildstate.go)
• Focus/Navigation: Always focus messages + select latest on channel enter; ESC respects hidden guilds panel (falls back to input); arrow keys: up/down same as k/j, left/right cycle between panels (configurable keybinds); vim-style h/l panel nav, i focus input, H toggle guilds, c channels picker, I attach file; input isolation (single-char keybinds blocked while typing)
• Config auto-create: config path ~/.config/discordo-plus/, auto-creates dir + default config on first run
• Dynamic input height: message input grows from 3 to 8 lines based on content
• Security hardening: path traversal prevention, HTTPS-only downloads, bounded downloads (100MB), exec.LookPath validation, atomic writes, restrictive perms, direct exec.Command (no sh -c)
• Bug fixes: Brotli body leak, cache type assertion panic, MarkRead uses newest fetched message ID
• Code structure: extracted url_extractor.go, embed_renderer.go, attachment_handler.go from messages_list.go; replaced open-golang with stdlib
• Reactions display: renders below content (drawReactions), bold for own, real-time gateway updates; E opens emoji picker to add reactions (emoji_picker.go)
• Search picker: / opens fuzzy search over current channel messages (search_picker.go)
• Thread indicators: "Thread: name" display, T navigates to thread (was t)
• User info popup: w shows author info overlay (user_info.go)
• Command mode: : opens vim-style input, supports :q/:quit/:logout (command_input.go)
• LRU cache cap: itemByID evicts stale entries past 500 items
• Reply quote italic: dim + italic style for reply lines; Z toggles reply collapse (shows > marker only)
• Timestamp toggle: t toggles timestamps on/off at runtime
• Wrap indentation: continuation lines get 2-space indent for visual clarity
• Picker browse mode: ESC in overlay pickers enters browse mode (j/k/g/G/i) via pickerBrowseHandleKey
• Link display compression: ui.LinkDisplayText() shows human-friendly labels instead of raw URLs in chat and embeds; ui.CdnDisplayName() cleans attachment filenames (encoded URLs → image.ext, UUIDs → image.ext); link preview embeds suppressed when URL already in message content (isLinkPreviewEmbed); removed show_attachment_links config (attachments always show as OSC 8 clickable filenames)

Adding Link Display Rules

To add a new site-specific URL label, edit ui.LinkDisplayText() in internal/ui/util.go:

1. Add a host match (host == "example.com" or strings.HasSuffix(host, ".example.com")) after the existing site blocks
2. Use segments (pre-split path segments) to extract meaningful parts (e.g., segments[1] for subreddit in /r/{sub})
3. Return a short label string (e.g., "SiteName - " + segments[1])
4. The raw URL is preserved as OSC 8 hyperlink metadata — only the visible text changes
5. CDN filenames also cleaned via ui.CdnDisplayName() — encoded URLs and UUIDs become image.ext, long names truncated
6. Link preview embeds (no description/fields/footer) are skipped when the URL is already in message content
7. Currently handled: Discord CDN (filename), Tenor (GIF), Substack (author), YouTube, X/Twitter, Reddit (subreddit), GitHub (owner/repo)
8. Fallback: host + truncated path (max 48 chars)

Config Fields We Added

• image_viewer — external image viewer command (default: "mpv", "default" = system opener)
• image_viewer_args — explicit viewer args list, overrides auto-detection (default: [], Wayland-friendly)
• image_save_dir — directory for saved images (supports ~/, default: current dir)
• keybinds.messages_list.save_image — save image keybind (default: S)
• keybinds.edit_config — open config in editor from help overlay (default: E)
• keybinds.toggle_help — changed default from ctrl+. to ?
• keybinds.messages_list.search — fuzzy search messages (default: /)
• keybinds.messages_list.open_thread — navigate to message's thread (default: T, was t)
• keybinds.messages_list.user_info — show author info popup (default: w)
• keybinds.command_mode — open vim-style command input (default: :)
• keybinds.guilds_tree.arrow_* / keybinds.messages_list.arrow_* — arrow key navigation (default: up/down/left/right)
• keybinds.focus_previous / keybinds.focus_next — vim-style panel nav (default: h/l)
• keybinds.focus_message_input — focus input (default: i)
• keybinds.toggle_guilds_tree — toggle sidebar (default: H)
• keybinds.toggle_channels_picker — channels picker (default: c)
• keybinds.attach_file — global attach file keybind (default: I)
• keybinds.messages_list.reply / reply_mention — swapped: r = reply (no mention), R = @reply
• keybinds.guilds_tree.yank_id / keybinds.messages_list.yank_id — copy ID (default: C, was i)
• keybinds.messages_list.toggle_timestamps — runtime timestamp toggle (default: t)
• keybinds.messages_list.toggle_replies — collapse/expand reply quotes (default: Z)
• keybinds.messages_list.add_reaction — open emoji picker (default: E)

Build & Run

• Build: go build -o discordo-plus .
• Install: sudo mv discordo-plus /usr/local/bin/
• Arch Linux: makepkg -si (uses PKGBUILD, installs via pacman)
• Run: discordo-plus
• Test: go test ./... (only config + keyring packages have tests)
• Dependencies: mpv (or configured image viewer), xdotool (optional, X11 geometry detection), xdg-open (Linux, for default opener)

Git

• Identity: claude <claude@altsol.dev>
• Commit style: type(scope): description (e.g., feat(ui/chat): add image viewer)
• Branch: master

Audit Status

• Research audits in ./research/: SECFILE.md, COMPLIANCE.md, TECHFILE.md
• Resolved all low-risk findings (marked ✅ FIXED in research files)
• Remaining unfixed: SEC #7 (raw events in debug), COMP #19-20 (perf), COMP #22/24 (linter/tests), TECH #2-3 (unmaintained deps)

Known Issues

• Discord ToS discourages third-party clients — use at own risk
• xdotool geometry detection only works on X11; on Wayland use image_viewer_args or compositor window rules for mpv positioning
• viewerArgs() only adds special flags for mpv; other viewers get plain viewer path invocation (use image_viewer_args to customize)