-- rvoice.lua — Right-Option push-to-talk for the rvoice helper.
--
-- Install:
--   1. Hammerspoon → Preferences → enable "Launch Hammerspoon at login"
--   2. Add this line to ~/.hammerspoon/init.lua:
--        require("rvoice")
--   3. Symlink this file so init.lua can find it:
--        ln -sfn ~/Code/@scripts/session-tools/hammerspoon/rvoice.lua \
--                ~/.hammerspoon/rvoice.lua
--   4. Reload Hammerspoon config (menu bar → Reload Config)
--   5. Grant Accessibility + Microphone permissions when prompted.
--
-- Behavior: hold Right-Option to talk. Release to transcribe + inject into
-- the active iTerm2 tab's remote tmux session. Taps shorter than 200ms are
-- ignored (configurable via RVOICE_MIN_MS env in rvoice config).

local M = {}

-- Resolve `rvoice` once at load. Hammerspoon's task PATH is barebones, so
-- prefer an explicit symlink in ~/.local/bin or fall back to the repo path.
local function resolveRvoice()
    local candidates = {
        os.getenv("HOME") .. "/.local/bin/rvoice",
        os.getenv("HOME") .. "/Code/@scripts/session-tools/bin/rvoice",
    }
    for _, p in ipairs(candidates) do
        local f = io.open(p, "r")
        if f then f:close(); return p end
    end
    return "rvoice"
end

local RVOICE = resolveRvoice()
local holding = false

-- Run rvoice <cmd> in the background; capture stderr to the system log so
-- failures are visible via Hammerspoon's console.
local function run(cmd)
    local t = hs.task.new("/bin/sh", function(exit, _, err)
        if exit ~= 0 then
            hs.printf("[rvoice] %s exited %d: %s", cmd, exit, err or "")
        end
    end, {"-c", RVOICE .. " " .. cmd})
    -- Inherit user shell env so GROQ_API_KEY (and PATH for ffmpeg/jq) work.
    t:setEnvironment(hs.execute("env", true):gsub("\n$", "") and nil or nil)
    t:start()
end

-- Right-Option keyDown/keyUp. Hammerspoon delivers modifier changes through
-- eventtap.flagsChanged; we watch for the rightAlt flag transitioning.
M.tap = hs.eventtap.new({ hs.eventtap.event.types.flagsChanged }, function(e)
    -- macOS exposes the side via a per-key mask. Right-Option is 0x40 in the
    -- raw `keyCode` event of type flagsChanged (code 61).
    local code = e:getKeyCode()
    if code ~= 61 then return false end  -- 61 = Right Option
    local flags = e:getFlags()
    local pressed = flags.alt or false
    if pressed and not holding then
        holding = true
        run("start")
    elseif (not pressed) and holding then
        holding = false
        run("stop")
    end
    return false  -- don't swallow the modifier; other apps may use it
end)

M.tap:start()
hs.alert.show("rvoice: Right ⌥ to talk")

return M