insta360-link-tools/obs/obs-linkctl.lua

--[[
obs-linkctl.lua - Insta360 Link control inside OBS.

Adds to OBS:
  * Hotkeys for tracking on/off/toggle, a named preset, and recenter.
    Bind them under Settings -> Hotkeys (search for "Insta360").
  * Scene automation: switching to a scene can set the camera's state, so a
    "Talking Head" scene enables tracking and an "Overhead" scene loads a
    preset without anyone pressing anything.
  * A startup action, which matters on Linux because the Link parks its
    gimbal facing down when idle. Pointing it home when OBS finishes
    loading undoes that automatically.

Install: Tools -> Scripts -> + -> pick this file.

OBS's own hotkeys only fire while OBS has focus under Wayland. For hotkeys
that work from anywhere, use the KDE shortcuts in ../kde/ instead; the two
are complementary and can both be installed.
--]]

local obs = obslua

-- Actions are plain linkctl argument lists, resolved when the action runs so
-- that edits to the preset name in the properties UI take effect immediately.
local cfg = {
    linkctl = "linkctl",
    device = "",
    force = true,
    preset = "home",
    scene_map_text = "",
    startup_action = "preset load home",
    log_output = false,
    enable_scenes = true,
}

local scene_map = {}
local hotkey_ids = {}
local last_run = { cmd = nil, at = 0 }
-- OBS owns this handle and keeps it alive for the lifetime of the script. We
-- hold it because a button callback is handed only (props, property) and so
-- has no other route to write a setting back.
local script_settings = nil

local HOTKEYS = {
    { name = "linkctl_tracking_toggle", label = "Insta360: toggle AI tracking",
      args = function() return { "tracking", "toggle" } end },
    { name = "linkctl_tracking_on", label = "Insta360: AI tracking on",
      args = function() return { "tracking", "on" } end },
    { name = "linkctl_tracking_off", label = "Insta360: AI tracking off",
      args = function() return { "tracking", "off" } end },
    { name = "linkctl_preset_load", label = "Insta360: load named preset",
      args = function() return { "preset", "load", cfg.preset } end },
    { name = "linkctl_center", label = "Insta360: recenter gimbal",
      args = function() return { "center" } end },
}

-- Tolerate obs being absent so the pure helpers below stay testable offline.
local function log(fmt, ...)
    local msg = string.format(fmt, ...)
    if obs then obs.script_log(obs.LOG_INFO, msg) end
end

local function warn(fmt, ...)
    local msg = string.format(fmt, ...)
    if obs then obs.script_log(obs.LOG_WARNING, msg) end
end

-- Single-quote for /bin/sh. Preset names come from user input and reach a
-- shell, so this is the boundary that has to hold.
local function shquote(s)
    return "'" .. (tostring(s):gsub("'", "'\\''")) .. "'"
end

-- Split an action string into arguments, honouring double quotes so that a
-- preset name containing a space still works.
local function tokenize(s)
    local out, i, n = {}, 1, #s
    while i <= n do
        local c = s:sub(i, i)
        if c:match("%s") then
            i = i + 1
        elseif c == '"' then
            local j = s:find('"', i + 1, true)
            if not j then
                table.insert(out, s:sub(i + 1))
                break
            end
            table.insert(out, s:sub(i + 1, j - 1))
            i = j + 1
        else
            local j = s:find("%s", i) or (n + 1)
            table.insert(out, s:sub(i, j - 1))
            i = j
        end
    end
    return out
end

local function build_cmd(args)
    local parts = { shquote(cfg.linkctl) }
    if cfg.force then
        table.insert(parts, "--force")
    end
    if cfg.device ~= "" then
        table.insert(parts, "--device")
        table.insert(parts, shquote(cfg.device))
    end
    for _, a in ipairs(args) do
        table.insert(parts, shquote(a))
    end
    return table.concat(parts, " ")
end

local function run(args)
    if not args or #args == 0 then
        return
    end
    local cmd = build_cmd(args)

    -- Studio mode and transitions can emit several scene events in a row.
    -- Collapse identical commands fired within 250ms of each other.
    local now = obs.os_gettime_ns()
    if last_run.cmd == cmd and (now - last_run.at) < 250000000 then
        return
    end
    last_run.cmd, last_run.at = cmd, now

    if cfg.log_output then
        -- Synchronous, so the camera's reply reaches the script log. Slightly
        -- blocking; intended for troubleshooting rather than normal use.
        local f = io.popen(cmd .. " 2>&1")
        if f then
            local out = f:read("*a")
            f:close()
            log("%s -> %s", cmd, (out:gsub("%s+$", "")))
        else
            warn("could not run: %s", cmd)
        end
    else
        -- Fire and forget: the shell backgrounds it, so the OBS UI thread
        -- never waits on the camera.
        os.execute(cmd .. " >/dev/null 2>&1 &")
    end
end

local function parse_scene_map(text)
    local map = {}
    for line in tostring(text):gmatch("[^\r\n]+") do
        local trimmed = line:match("^%s*(.-)%s*$")
        if trimmed ~= "" and not trimmed:match("^#") then
            local scene, action = trimmed:match("^(.-)%s*=%s*(.*)$")
            if scene and scene ~= "" and action and action ~= "" then
                map[scene] = action
            else
                warn("ignoring unparsable scene mapping: %s", trimmed)
            end
        end
    end
    return map
end

local function current_scene_name()
    local src = obs.obs_frontend_get_current_scene()
    if not src then
        return nil
    end
    local name = obs.obs_source_get_name(src)
    obs.obs_source_release(src)
    return name
end

local function on_scene_changed()
    if not cfg.enable_scenes then
        return
    end
    local name = current_scene_name()
    if not name then
        return
    end
    local action = scene_map[name]
    if action then
        run(tokenize(action))
    end
end

local function on_frontend_event(event)
    if event == obs.OBS_FRONTEND_EVENT_SCENE_CHANGED then
        on_scene_changed()
    elseif event == obs.OBS_FRONTEND_EVENT_FINISHED_LOADING then
        if cfg.startup_action ~= "" then
            run(tokenize(cfg.startup_action))
        end
    end
end

----------------------------------------------------------------------------
-- Properties UI
----------------------------------------------------------------------------

function script_description()
    return [[<b>Insta360 Link control</b><br/>
Drives <code>linkctl</code> for AI tracking, presets and the gimbal.<br/><br/>
Bind the hotkeys under <b>Settings &rarr; Hotkeys</b> ("Insta360").<br/>
For hotkeys that work outside OBS, install the KDE shortcuts shipped
alongside this script.]]
end

local function populate_scenes()
    -- Prefill the mapping box with every scene currently in the collection,
    -- so the user edits a list rather than guessing exact scene names.
    if not script_settings then
        return false
    end
    local scenes = obs.obs_frontend_get_scenes()
    if not scenes then
        return false
    end
    local lines = {}
    for _, src in ipairs(scenes) do
        local name = obs.obs_source_get_name(src)
        -- Keep any action already mapped to this scene.
        table.insert(lines, string.format("%s = %s", name, scene_map[name] or ""))
    end
    obs.source_list_release(scenes)

    local text = table.concat(lines, "\n")
    obs.obs_data_set_string(script_settings, "scene_map_text", text)
    cfg.scene_map_text = text
    scene_map = parse_scene_map(text)
    -- true asks OBS to redraw the properties pane so the new text appears.
    return true
end

function script_properties()
    local props = obs.obs_properties_create()

    obs.obs_properties_add_path(props, "linkctl", "linkctl binary",
        obs.OBS_PATH_FILE, "", "/usr/local/bin/linkctl")
    obs.obs_properties_add_text(props, "device",
        "Video device (blank = auto-detect)", obs.OBS_TEXT_DEFAULT)
    obs.obs_properties_add_bool(props, "force",
        "Act even when no application is using the camera (--force)")
    obs.obs_properties_add_text(props, "preset",
        "Preset name for the 'load named preset' hotkey", obs.OBS_TEXT_DEFAULT)

    obs.obs_properties_add_text(props, "startup_action",
        "Run when OBS finishes loading (blank = nothing)", obs.OBS_TEXT_DEFAULT)

    obs.obs_properties_add_bool(props, "enable_scenes",
        "React to scene changes")
    local map = obs.obs_properties_add_text(props, "scene_map_text",
        "Scene actions, one per line: Scene Name = linkctl args",
        obs.OBS_TEXT_MULTILINE)
    obs.obs_property_set_long_description(map,
        "Example:\n" ..
        "Talking Head = tracking on\n" ..
        "Overhead = preset load overhead\n" ..
        "Slides = tracking off\n\n" ..
        "Blank actions and lines starting with # are ignored.")
    obs.obs_properties_add_button(props, "fill_scenes",
        "Insert current scene names", populate_scenes)

    obs.obs_properties_add_bool(props, "log_output",
        "Log linkctl output to the script log (for troubleshooting)")

    obs.obs_properties_add_button(props, "test_tracking_on", "Test: tracking on",
        function() run({ "tracking", "on" }) return false end)
    obs.obs_properties_add_button(props, "test_tracking_off", "Test: tracking off",
        function() run({ "tracking", "off" }) return false end)
    obs.obs_properties_add_button(props, "test_preset", "Test: load preset",
        function() run({ "preset", "load", cfg.preset }) return false end)
    obs.obs_properties_add_button(props, "test_center", "Test: recenter",
        function() run({ "center" }) return false end)

    return props
end

function script_defaults(settings)
    obs.obs_data_set_default_string(settings, "linkctl", "linkctl")
    obs.obs_data_set_default_string(settings, "device", "")
    obs.obs_data_set_default_bool(settings, "force", true)
    obs.obs_data_set_default_string(settings, "preset", "home")
    obs.obs_data_set_default_string(settings, "startup_action", "preset load home")
    obs.obs_data_set_default_bool(settings, "enable_scenes", true)
    obs.obs_data_set_default_string(settings, "scene_map_text", "")
    obs.obs_data_set_default_bool(settings, "log_output", false)
end

function script_update(settings)
    script_settings = settings
    cfg.linkctl = obs.obs_data_get_string(settings, "linkctl")
    cfg.device = obs.obs_data_get_string(settings, "device")
    cfg.force = obs.obs_data_get_bool(settings, "force")
    cfg.preset = obs.obs_data_get_string(settings, "preset")
    cfg.startup_action = obs.obs_data_get_string(settings, "startup_action")
    cfg.enable_scenes = obs.obs_data_get_bool(settings, "enable_scenes")
    cfg.scene_map_text = obs.obs_data_get_string(settings, "scene_map_text")
    cfg.log_output = obs.obs_data_get_bool(settings, "log_output")

    if cfg.linkctl == "" then
        cfg.linkctl = "linkctl"
    end
    scene_map = parse_scene_map(cfg.scene_map_text)
end

function script_load(settings)
    script_settings = settings
    for _, def in ipairs(HOTKEYS) do
        local id = obs.obs_hotkey_register_frontend(def.name, def.label,
            function(pressed)
                if pressed then
                    run(def.args())
                end
            end)
        hotkey_ids[def.name] = id
        local saved = obs.obs_data_get_array(settings, def.name)
        obs.obs_hotkey_load(id, saved)
        obs.obs_data_array_release(saved)
    end
    obs.obs_frontend_add_event_callback(on_frontend_event)
end

function script_save(settings)
    for name, id in pairs(hotkey_ids) do
        local a = obs.obs_hotkey_save(id)
        obs.obs_data_set_array(settings, name, a)
        obs.obs_data_array_release(a)
    end
end

function script_unload()
    obs.obs_frontend_remove_event_callback(on_frontend_event)
end

-- Exposed only when loaded outside OBS, by the test harness in ../tests.
-- OBS discards a chunk's return value, but staying silent there keeps the
-- script's contract with OBS unambiguous.
if not rawget(_G, "obslua") then
    return {
        shquote = shquote,
        tokenize = tokenize,
        parse_scene_map = parse_scene_map,
        build_cmd = build_cmd,
        cfg = cfg,
    }
end