1# plugin
2
3Lua-based plugin system for extending Matcha. Plugins are loaded from `~/.config/matcha/plugins/` and run inside a sandboxed Lua VM (no `os`, `io`, or `debug` libraries).
4
5## How it works
6
7The `Manager` creates a Lua VM at startup, registers the `matcha` module, and loads all plugins from the user's plugins directory. Plugins can be either a single `.lua` file or a directory with an `init.lua` entry point.
8
9Plugins interact with Matcha by registering callbacks on hooks:
10
11```lua
12local matcha = require("matcha")
13
14matcha.on("email_received", function(email)
15 matcha.log("New email from: " .. email.from)
16 matcha.notify("New mail!", 3)
17end)
18```
19
20## Lua API (`matcha` module)
21
22| Function | Description |
23|----------|-------------|
24| `matcha.on(event, callback)` | Register a callback for a hook event |
25| `matcha.log(msg)` | Log a message to stderr |
26| `matcha.notify(msg [, seconds])` | Show a temporary notification in the TUI (default 2s) |
27| `matcha.set_status(area, text)` | Set a persistent status string for a view area (`"inbox"`, `"composer"`, `"email_view"`) |
28| `matcha.set_compose_field(field, value)` | Set a compose field value (`"to"`, `"cc"`, `"bcc"`, `"subject"`, `"body"`) |
29| `matcha.bind_key(key, area, description, callback)` | Register a custom keyboard shortcut for a view area (`"inbox"`, `"email_view"`, `"composer"`) |
30| `matcha.http(options)` | Make an HTTP request (see below) |
31| `matcha.prompt(placeholder, callback)` | Open a text input overlay in the composer (see below) |
32| `matcha.style(text, opts)` | Wrap `text` in lipgloss styling and return an ANSI-styled string (see below) |
33| `matcha.settings(spec)` | Declare configurable settings; returns a read-only proxy table for live values (see below) |
34| `matcha.get_setting(key [, plugin])` | Look up a setting value by key (defaults to current plugin) |
35
36## Hook events
37
38| Event | Callback argument | Description |
39|-------|-------------------|-------------|
40| `startup` | — | Matcha has started |
41| `shutdown` | — | Matcha is exiting |
42| `email_received` | Lua table with `uid`, `from`, `to`, `subject`, `date`, `is_read`, `account_id`, `folder` | New email arrived |
43| `email_viewed` | Same as `email_received` | User opened an email |
44| `email_send_before` | Table with `to`, `cc`, `subject`, `account_id` | About to send an email |
45| `email_send_after` | Same as `email_send_before` | Email sent successfully |
46| `folder_changed` | Folder name (string) | User switched folders |
47| `composer_updated` | Table with `body`, `body_len`, `subject`, `to`, `cc`, `bcc` | Composer content changed |
48| `email_body_render` | `(email_table, rendered, raw)` — return a string to replace the rendered body, or `nil` to keep it | About to display an email body. `rendered` is the ANSI-styled display string; `raw` is the original message source (HTML or plain text). Use for recoloring, bold/italic, removing parts, or fully replacing the displayed body with parsed output |
49
50## HTTP requests
51
52`matcha.http(options)` makes an HTTP request and returns `(response, err)`. Options is a table with:
53
54- `url` (string, required) — only `http` and `https` schemes
55- `method` (string, optional, default `"GET"`)
56- `headers` (table, optional)
57- `body` (string, optional)
58
59The response table has `status` (number), `body` (string), and `headers` (table with lowercase keys).
60
61Safety limits: 10s timeout, 1 MB response body cap.
62
63```lua
64local res, err = matcha.http({
65 url = "https://api.example.com/webhook",
66 method = "POST",
67 headers = { ["Content-Type"] = "application/json" },
68 body = '{"text":"hello"}',
69})
70if err then
71 matcha.log("error: " .. err)
72 return
73end
74matcha.log("status: " .. res.status)
75```
76
77## User input prompts
78
79`matcha.prompt(placeholder, callback)` opens a text input overlay in the composer. When the user presses Enter, the callback receives their input string. Pressing Esc cancels without calling the callback.
80
81Only works inside a `bind_key` callback for the `"composer"` area.
82
83```lua
84matcha.bind_key("ctrl+r", "composer", "rewrite", function(state)
85 matcha.prompt("Enter instruction:", function(input)
86 -- input is the user's text
87 matcha.log("User typed: " .. input)
88 end)
89end)
90```
91
92## Body rendering
93
94`matcha.on("email_body_render", function(email, rendered, raw) ... end)` runs
95after the email body has been converted to its final ANSI-styled form and
96before it is placed in the viewport. The callback receives:
97
98- `email`: the same table as `email_viewed`
99- `rendered`: the current display string (ANSI-styled, post-HTML→terminal)
100- `raw`: the original message body (HTML or plain text) — useful for parsing
101 the source instead of the rendered output
102
103Return a new string to replace the rendered body, or `nil` to leave it
104unchanged. Multiple registered callbacks chain in registration order; each
105subsequent callback sees the previous callback's rendered output, but always
106the same raw source.
107
108`matcha.style(text, opts)` wraps `text` in lipgloss styling. `opts` keys (all
109optional):
110
111- `color`, `bg`: string color (hex `"#rrggbb"`, named like `"red"`, or ANSI 256 number as string)
112- `bold`, `italic`, `underline`, `strikethrough`, `faint`, `blink`, `reverse`: bool
113
114```lua
115local matcha = require("matcha")
116
117matcha.on("email_body_render", function(email, rendered, raw)
118 -- highlight TODO in red bold (operates on rendered)
119 rendered = rendered:gsub("TODO", function(m)
120 return matcha.style(m, { color = "#ff0000", bold = true })
121 end)
122 -- italicize anything in *asterisks*
123 rendered = rendered:gsub("%*([^%*]+)%*", function(m)
124 return matcha.style(m, { italic = true })
125 end)
126 -- strip a tracking footer entirely
127 rendered = rendered:gsub("%-%-%-%s*Sent via Tracker.*$", "")
128 return rendered
129end)
130
131-- Parse the raw source and prepend a summary; works regardless of HTML markup.
132matcha.on("email_body_render", function(email, rendered, raw)
133 local urls = {}
134 for url in raw:gmatch("https?://[%w%-_%.~%?=&/%%#:]+") do
135 urls[#urls + 1] = url
136 end
137 local header = matcha.style("URLs: " .. #urls, { bold = true }) .. "\n\n"
138 return header .. rendered
139end)
140```
141
142Caveats:
143
144- The `rendered` string already contains ANSI escape sequences from the
145 HTML→terminal conversion. Patterns that straddle existing escapes will not
146 match — match plain text spans for predictable behavior, or operate on `raw`.
147- Returning a fully replaced string fully takes over the displayed body. To
148 build styled output from scratch, compose with `matcha.style` and join with
149 newlines.
150
151## User-configurable settings
152
153`matcha.settings(spec)` declares configurable options for a plugin. Call it
154once at the top level of the plugin file. `spec` is a table mapping a setting
155key to `{ type, default, label, description }`. Supported types:
156
157- `"boolean"` — toggled in the TUI with a checkbox-style on/off selector
158- `"number"` — edited with a numeric input
159- `"string"` — edited with a text input
160
161The function returns a read-only proxy table whose fields reflect the
162currently saved value (or the default when unset). Read fields anywhere,
163including inside hook callbacks:
164
165```lua
166local matcha = require("matcha")
167
168local cfg = matcha.settings({
169 threshold = { type = "number", default = 5, label = "Subject length threshold" },
170 enabled = { type = "boolean", default = true, label = "Enable warnings" },
171 suffix = { type = "string", default = "!", label = "Notification suffix" },
172})
173
174matcha.on("email_received", function(email)
175 if cfg.enabled and #email.subject > cfg.threshold then
176 matcha.notify("Long subject" .. cfg.suffix, 3)
177 end
178end)
179```
180
181Values are persisted in `~/.config/matcha/config.json` under
182`plugin_settings`. Edit them in **Settings → Plugins** in the TUI; booleans
183toggle with `enter`/`space`, numbers and strings open a text editor.
184
185## Available plugins
186
187The following example plugins ship in `~/.config/matcha/plugins/`:
188
189- `email_age.lua`
190- `recipient_counter.lua`
191
192## Files
193
194| File | Description |
195|------|-------------|
196| `plugin.go` | Plugin manager — Lua VM setup, plugin discovery and loading, notification/status state |
197| `hooks.go` | Hook definitions, callback registration, and hook invocation helpers |
198| `api.go` | `matcha` Lua module registration (`on`, `log`, `notify`, `set_status`, `set_compose_field`, `bind_key`, `http`, `prompt`, `style`) |
199| `http.go` | `matcha.http()` implementation — HTTP client with timeout and body size limits |
200| `prompt.go` | `matcha.prompt()` implementation — user input overlay for the composer |