#!/usr/bin/env luajit

--[[ This block is what system V LSB expects.
### BEGIN INIT INFO
# Provides:          aataaj
# Required-Start:    $local_fs
# Required-Stop:
# X-Start-Before:    alsa-utils espeakup
# Default-Start:     S
# Default-Stop:
# Short-Description: Scan for audio devices.
# Description:       Scan for all audio devices and produce an
#                    asound.conf include file fragment.
### END INIT INFO
]]

local Help = [[
This is part of the AllAudioToALSAandJACK project, aataaj for short,
pronounced like "attach".

The purpose is to scan for all ALSA / asound audio devices, and hook them
all up to ALSA and JACK.  Then it starts up JACK, and hooks up any
joysticks it finds as MIDI controllers.  So any ALSA application gets routed through
JACK.

This is very rough for now, only just started writing it.  The stop
command is particularly crude and violent, lots of pkill.

Since it isn't a package yet, some setup is needed.

The packages you need installed are -
    luajit
    jackd2
    jack-tools for jack-plumbing, but other patch persistance methods could be used.
    a2jmidid
    zita-ajbridge
    aseqjoy

    qjackctl can be used as a visual patchbay, though I prefer catia from the KXStudio repos.

You need to have the snd-aloop kernel module loaded.

The aataaj.lua script should be run at boot time, put it into
/etc/init.d/ and activate it with -

update-rc.d aataaj.lua defaults

It scans for your sound devices and creates /var/lib/aataaj/asoundrc. 
You can run it manually with "aataaj start" each time you need to change
your devices.



"aataaj JACK" should be called on user login.  Probably don't need to run "aataaj stop" on
user logout.

It starts up JACK and friends, and creates JACK devices for all the
things "aataaj start" found.  It creates the cloop and ploop devices that
catch everything ALSA does.  Then creates MIDI devices for all your
joysticks.


Alas ~/.asoundrc doesn't understand ~ or $HOME, or even "try the current
directory" it seems.  So you have to hard code the path.  Make sure your
~/.asoundrc or /etc/asoundrc includes something like this -

</var/lib/aataaj/asoundrc>



"aataaj stop" closes down everything "aataaj JACK" started up.



TODO - Leave it running, and hotplug ALSA / asound audio devices. 
	a2jmidid takes care of hotplugging MIDI devices.
	Though I think I still need to deal with hotplugged joysticks.

NOTE - Seems both ALSA and JACK are per user.  So you need to run
"aataaj JACK" for each user.

]]



-- Most of this APT stuff was copied from apt-panopticon.
local APT = {}

APT.readCmd = function(cmd)
    local result = {}
    local output = io.popen(cmd)
    if nil ~= output then
	for l in output:lines() do
	    table.insert(result, l)
	end
    end
    -- While this does return the same things as os.execute(), it's just as useless.
    output:close()
    return result
end

APT.exe = function(c)
    local exe = {status = 0, lines = {}, log = true, cmd = c .. ' ', command = c}

    function exe:log()
	self.log = true
	return self
    end
    function exe:Nice(c)
	if nil == c then
	    self.cmd = 'ionice -c3 nice -n 19 ' .. self.cmd
	else
	    self.cmd = self.cmd .. 'ionice -c3 nice -n 19 ' .. c .. ' '
	end
	return self
    end
    function exe:timeout(c)
	-- timeout returns a status of - command status if --preserve-status; "128+9" (actually 137) if --kill-after ends up being done; 124 if it had to TERM; command status if all went well.
	-- --kill-after means "send KILL after TERM fails.
	if nil == c then
	    self.cmd = 'timeout --kill-after=10.0 --foreground 42.0s ' .. self.cmd
	else
	    self.cmd = 'timeout --kill-after=10.0 --foreground ' .. c .. ' ' .. self.cmd
	end
	return self
    end
    function exe:also(c)
	if nil == c then c = '' else c = ' ' .. c end
	self.cmd = self.cmd .. ';' .. c .. ' '
	return self
    end
    function exe:And(c)
	if nil == c then c = '' else c = ' ' .. c end
	self.cmd = self.cmd .. '&&' .. c .. ' '
	return self
    end
    function exe:Or(c)
	if nil == c then c = '' end
	self.cmd = self.cmd .. '|| ' .. c .. ' '
	return self
    end
    function exe:noErr()
	self.cmd = self.cmd .. '2>/dev/null '
	return self
    end
    function exe:wait(w)
	self.cmd = self.cmd .. '&& touch ' .. w .. ' '
	return self
    end
    function exe:Do()
    --[[    "The condition expression of a control structure can return any
	    value. Both false and nil are considered false. All values different
	    from nil and false are considered true (in particular, the number 0
	    and the empty string are also true)."
	says the docs, I beg to differ.]]
	if true == self.log then D("  executing - &nbsp; <code>" .. self.cmd .. "</code>") end
	--[[ Damn os.execute()
	    Lua 5.1 says it returns "a status code, which is system-dependent"
	    Lua 5.2 says it returns true/nil, "exit"/"signal", the status code.
	    I'm getting 7168 or 0.  No idea what the fuck that is.
	local ok, rslt, status = os.execute(s)
	]]
	self.lines = APT.readCmd(self.cmd .. '; echo "$?"', 'r')
	-- The last line will be the command's returned status, collect everything else in result.
	self.status = tonumber(self.lines[#self.lines])
	self.lines[#self.lines] = nil
--	self.result = '\n'
--	for i,l in ipairs(self.lines) do
--	    self.result = self.result .. l .. "\n"
--	end
	if (137 == self.status) or (124 == self.status) then
	    print("timeout killed " .. self.status .. ' ' .. self.command)
	    print('ERROR ' .. "timeout killed " .. self.status .. ' ' .. self.command)
	elseif (nil == self.status) then
	    print("STATUS |" .. "NIL" .. '| ' .. self.command)
	elseif (0 ~= self.status) then
	    print("STATUS |" .. self.status .. '| ' .. self.command)
	end
	return self
    end
    function exe:fork(host)
	if nil ~= host then self.cmd = self.cmd .. ';  r=$?; if [ $r -ge 124 ]; then echo "$r ' .. host .. ' failed forked command ' .. string.gsub(self.cmd, '"', "'") .. '"; fi' end
	self.cmd = '{ ' .. self.cmd .. '; } &'
	if true == self.log then D("  forking - &nbsp; <code>" .. self.cmd .. "</code>") end
	os.execute(self.cmd)
	return self
    end
    return exe
end

APT.exists = function(c)
    if 0 == APT.exe('which ' .. c):Do().status then return true end
    return false
end

APT.killEmAll = function(all)
    for i,l in ipairs(all) do
	local c = 0
	while 0 ~= tonumber(APT.exe("pgrep -u $USER -xc " .. l):Do().lines[1]) do
	    local s = 'TERM'
	    if c > 0 then s = 'KILL'; APT.exe("sleep " .. c):Do() end
	    print(  "pkill -" .. s .. " -u $USER -x " .. l)
	    APT.exe("pkill -" .. s .. " -u $USER -x " .. l):Do()
	    c = c + 1
	end
    end
end



local args = {...}
if 0 ~= #args then
--    for i,a in pairs(args) do
--	print('Argument ' .. i .. ' = ' .. a)
--    end

    if     'start'        == args[1] then
    elseif 'stop'         == args[1] then
	APT.killEmAll{'qsynth'}
	APT.exe("a2j_control --stop"):Do()
	APT.exe("sleep 2"):Do()
	APT.exe("a2j_control --exit"):Do()
	APT.exe("sleep 2"):Do()
	APT.killEmAll{'alsa_in', 'alsa_out', 'zita-a2j', 'zita-j2a',  'aseqjoy', 'jack-plumbing'}
	APT.exe("sleep 2"):Do()
	APT.exe("jack_control stop"):Do()
	APT.exe("sleep 2"):Do()
	APT.exe("jack_control exit"):Do()
	APT.exe("sleep 2"):Do()
	APT.killEmAll{'jmcore', 'qjackctl'}
	-- Catia is python, and no easy way to kill it.
	-- Also it keeps jackdbus alive, no matter how hard you kill it.
	APT.exe("pkill -TERM -u $USER -f catia"):Do()
	APT.exe("sleep 2"):Do()
	APT.killEmAll{'jackdbus', 'a2jmidid'}
	return(0)
    elseif 'JACK'         == args[1] then
    elseif 'restart'      == args[1] then args[1] = 'start'
    elseif 'force-reload' == args[1] then args[1] = 'start'
    elseif 'status'       == args[1] then
	return(0)
    elseif 'help'         == args[1] then
	print(Help)
	return(0)
    elseif '--help'       == args[1] then
	print(Help)
	return(0)
    else
	print("Usage: /etc/init.d/aataaj.lua {start|stop|restart|force-reload|status}")
	return(1)
    end
else
    print("Usage: /etc/init.d/aataaj.lua {help|start|stop|restart|force-reload|status|JACK}")
    return(1)
end




-- CHANGE these to suit.
local asoundrcPath = '/var/lib/aataaj'
local asoundrc = 'asoundrc'
local GUI = 'qjackctl'
if APT.exists('catia') then GUI = 'catia' end
local alias = {
--	{name='Screen', dev='HDMI9'},
    }

local speaker = 'espeak'
if APT.exists('espeak-ng') then speaker = 'espeak-ng' end

local Cards = {}

print('Scanning for audio devices.')
local cards = APT.exe('ls -d1 /proc/asound/card[0-9]*'):noErr():Do()
for  i,l in ipairs(cards.lines) do
    local f, e = io.open(l .. '/id', "r")
    if nil == f then print("Could not open " .. l .. '/id') else
	Cards[l] = {path = l, name = f:read("*a"):sub(1, -2), devs = {}, captureDevs = {}, playbackDevs = {}}
	if "Loopback" ~= Cards[l]['name'] then
	    Cards[l]['capture'] = APT.exe('ls -d1 ' .. l .. '/pcm[0-9]*c*'):noErr():Do()
	    for  j,c in ipairs(Cards[l]['capture'].lines) do
		local n = c:match(".*pcm(%d+).*")
		Cards[l]['captureDevs'][j] = n
		Cards[l]['devs'][n] = n
		print("\tFound capture device: " .. Cards[l]['name'] .. "\tDEVICE: " .. Cards[l]['captureDevs'][j] .. ' ' .. n)
	    end
	    Cards[l]['playback'] = APT.exe('ls -d1 ' .. l .. '/pcm[0-9]*p*'):noErr():Do()
	    for  j,p in ipairs(Cards[l]['playback'].lines) do
		local n = p:match(".*pcm(%d+).*")
		Cards[l]['playbackDevs'][j] = n
		Cards[l]['devs'][n] = n
		print("\tFound playback device " .. i - 1 .. " : " .. Cards[l]['name'] .. "\tDEVICE: " .. Cards[l]['playbackDevs'][j] .. ' ' .. n)
		if 'JACK' ~= args[1] then
		    print('\t\tALSA_CARD=' .. i - 1 .. ' ' .. speaker .. ' "Found playback device ' .. i - 1 .. ' : ' .. Cards[l]['name'] .. ' DEVICE: ' .. Cards[l]['playbackDevs'][j] .. ' ' .. n .. '"')
		    APT.exe('ALSA_CARD=' .. i - 1  .. ' ' .. speaker .. ' "Found playback device ' .. i - 1 .. ' : ' .. Cards[l]['name'] .. ' DEVICE: ' .. Cards[l]['playbackDevs'][j] .. ' ' .. n .. '"'):noErr():Do()
		    APT.exe('sleep 1')
		end
	    end
	end
    end
end

if 'start' == args[1] then
    APT.exe('mkdir -p ' .. asoundrcPath):Do()
    local a, e = io.open(asoundrcPath .. '/jack-plumbing', "w")
    if nil == a then print("Could not open " .. asoundrcPath .. '/jack-plumbing') else
	a:write([[
(connect "system:capture_1" "ploop:playback_1")
(connect "system:capture_2" "ploop:playback_2")
(connect "cloop:capture_1" "system:playback_1")
(connect "cloop:capture_2" "system:playback_2")
(connect "cloop:capture_1" "(.*)-in:playback_1")
(connect "cloop:capture_2" "(.*)-in:playback_2")

(connect "qsynth:left"  "(.*)-in:playback_1")
(connect "qsynth:right"  "(.*)-in:playback_2")
	    ]])
	a:close()
    end
    local a, e = io.open(asoundrcPath .. '/' .. asoundrc, "w")
    if nil == a then print("Could not open " .. asoundrcPath .. '/' .. asoundrc) else
	for  i,C in pairs(Cards) do
	    for  j,c in pairs(C['devs']) do
		a:write("pcm." .. C['name'] .. j .. " {\n")
		a:write("   type hw\n")
		a:write("   card " .. C['name'] .. "\n")
		a:write("   device " .. C['devs'][j] .. "\n")
		a:write("}\n")
		a:write("ctl." .. C['name'] .. j .. " {\n")
		a:write("   type hw\n")
		a:write("   card " .. C['name'] .. "\n")
		a:write("   device " .. C['devs'][j] .. "\n")
		a:write("}\n\n")
	    end
	end
	a:write([[
#################################################################################################################################

# The complex way - https://alsa.opensrc.org/Jack_and_Loopback_device_as_Alsa-to-Jack_bridge

# More custom version, but it didn't work for me.
# hardware 0,0 : used for ALSA playback
#pcm.loophw00 {
#  type hw
#  card Loopback
#  device 0
#  subdevice 0
#  format S32_LE
#  rate 48000
#}

# playback PCM device: using loopback subdevice 0,0
# Don't use a buffer size that is too small. Some apps 
# won't like it and it will sound crappy 

#pcm.amix {
#  type dmix
#  ipc_key 219345
#  slave {
#    pcm loophw00
##    period_size 4096
##    periods 2
#  }
#}

# software volume
#pcm.asoftvol {
#  type softvol
#  slave.pcm "amix"

#  control { name PCM }

#  min_dB -51.0
#  max_dB   0.0
#}


# for jack alsa_in: looped-back signal at other ends
#pcm.cloop {
#  type hw
#  card Loopback
#  device 1
#  subdevice 0
#  format S32_LE
#  rate 48000
#}

# hardware 0,1 : used for ALSA capture
#pcm.loophw01 {
#  type hw
#  card Loopback
#  device 0
#  subdevice 1
#  format S32_LE
#  rate 48000
#}

# for jack alsa_out: looped-back signal at other end
#pcm.ploop {
#  type hw
#  card Loopback
#  device 1
#  subdevice 1
#  format S32_LE
#  rate 48000
#}

# duplex device combining our PCM devices defined above
#pcm.aduplex {
#  type asym
#  playback.pcm "asoftvol"
#  capture.pcm "loophw01"
#}

# default device
#pcm.!default {
#  type plug
#  slave.pcm aduplex

#  hint {
#       show on
#       description "Duplex Loopback"
#  }
#}



# Generic method seems to work better.
# playback PCM device: using loopback subdevice 0,0
pcm.amix {
  type dmix
  ipc_key 219345
  slave.pcm "hw:Loopback,0,0"
}

# capture PCM device: using loopback subdevice 0,1
pcm.asnoop {
  type dsnoop
  ipc_key 219346
  slave.pcm "hw:Loopback,0,1"
}

# duplex device combining our PCM devices defined above
pcm.aduplex {
  type asym
  playback.pcm "amix"
  capture.pcm "asnoop"
}

# ------------------------------------------------------
# for jack alsa_in and alsa_out: looped-back signal at other ends
pcm.ploop {
  type plug
  slave.pcm "hw:Loopback,1,1"
}

pcm.cloop {
  type dsnoop
  ipc_key 219348
  slave.pcm "hw:Loopback,1,0"
}

# ------------------------------------------------------
# default device

pcm.!default {
  type plug
  slave.pcm "aduplex"
}
	    ]])
	a:close()
    end
elseif 'JACK' == args[1] then
    print('')
    print("Start up JACK and friends.")
    print("jack_control")
    APT.exe('jack_control start'):Do()
    APT.exe('jack_control ds alsa'):Do()
    --jack_control dps device hw:RIG,0
    local r = APT.exe('jack_control status'):Do().status
    while r ~= 0 do
	print("Waiting for JACK - sleep 1")
	APT.exe('sleep 1'):Do()
	r = APT.exe('jack_control status'):Do().status
    end
    if nil ~= GUI then
	print(GUI)
	APT.exe(GUI):fork()
    end
    if APT.exists('jack-plumbing') then
	print("jack-plumbing")
	APT.exe('jack-plumbing -o /var/lib/aataaj/jack-plumbing 2>/dev/null'):fork()
    end
    if APT.exists('a2j_control') then
	-- Bridge ALSA ports to JACK ports.  Only handles MIDI.
	-- MIDI via a2jmidid.  The --ehw enables hardware ports as well, equal to using the seq MIDI drivare according to https://freeshell.de/~murks/posts/ALSA_and_JACK_MIDI_explained_(by_a_dummy_for_dummies)/
	--a2j_control actually starts a2jmidid.
	----a2jmidid -e -u &
	-- I think the jack_control start and my current alsa config means a2jmidid gets started anyway.  But seem to need this bit to get the joystick covered.
	print("a2j_control")
	APT.exe('a2j_control --ehw && a2j_control --start'):Do()
--	print("sleep 2")
--	APT.exe('sleep 2'):Do()
	print("")
    end


    local AIN = "alsa_in"
    if APT.exists('zita-a2j') then AIN = 'zita-a2j' end
    local AOUT = "alsa_out"
    if APT.exists('zita-j2a') then AOUT = 'zita-j2a' end

    print("Basic ALSA sound devices converted to JACK.")
    for  i,C in pairs(alias) do
	print('HW playback: ' .. C['name'] .. '\tDEVICE: ' .. C['dev'])
	APT.exe(AOUT .. ' -j ' .. C['name'] .. ' -d ' .. C['dev']):fork()
    end
    print("HW playback: cloop\tDEVICE: cloop")
    -- No idea why, cloop wont work with zita-a2j.
    APT.exe('alsa_in  -j cloop  -d cloop'):fork()
    --APT.exe('sleep 1'):Do()
    --APT.exe('jack_connect cloop:capture_1 system:playback_1'):Do()
    --APT.exe('jack_connect cloop:capture_2 system:playback_2'):Do()
    print("HW playback: ploop\tDEVICE: ploop")
    APT.exe('alsa_out -j ploop  -d ploop'):fork()
    --APT.exe('sleep 1'):Do()
    --APT.exe('jack_connect system:capture_1 ploop:playback_1'):Do()
    --APT.exe('jack_connect system:capture_2 ploop:playback_2'):Do()


    print("")

    print("Rest of ALSA sound devices converted to JACK.")
    for  i,C in pairs(Cards) do
	for  j,c in ipairs(C['playbackDevs']) do
	    print("HW playback: " .. C['name'] .. "\tDEVICE: " .. C['playbackDevs'][j])
	    APT.exe(AOUT .. ' -j ' .. C['name'] .. "_" .. C['playbackDevs'][j] .. '-in -d ' .. C['name'] .. C['playbackDevs'][j]):fork()
    --	APT.exe('sleep 1'):Do()
    --	APT.exe('jack_connect cloop:capture_1 ' .. C['name'] .. '_' .. C['playbackDevs'][j] .. '-in' .. ':playback_1'):Do()
    --	APT.exe('jack_connect cloop:capture_2 ' .. C['name'] .. '_' .. C['playbackDevs'][j] .. '-in' .. ':playback_2'):Do()
	end
	for  j,c in ipairs(C['captureDevs']) do
	    print("HW capture: " .. C['name'] .. "\tDEVICE: " .. C['captureDevs'][j])
	    APT.exe(AIN .. ' -j ' .. C['name'] .. "_" .. C['captureDevs'][j] .. '-out -d ' .. C['name'] .. C['captureDevs'][j]):fork()
	end
    end
    print("")

    if APT.exists('aseqjoy') then
	print("Scanning for joysticks.")
	local sticks = APT.exe('ls -1 /dev/input/js[0-9]*'):noErr():Do()
	for  i,l in ipairs(sticks.lines) do
	    print("aseqjoy " .. l)
	    -- Buttons switch to that numbered MIDI channel, defaults to 1.
	    -- Axis are mapped to MIDI controllers 10 - 15
	    -- -r means to use high resolution MIDI values.
	    APT.exe('aseqjoy -d ' .. l:sub(-1,-1) .. ' -r'):fork()
	end
	print("")
    end

    if APT.exists('jack-plumbing') then
	print('Stop our jack-plumbing, eventually.')
	APT.exe('sleep 4'):Do()
	APT.killEmAll{"jack-plumbing"}
    end

    if APT.exists('~/.aataaj_JACK.lua') then
	print('Running users aataaj_JACK.lua')
	APT.exe('~/.aataaj_JACK.lua'):Do()
    end
end