--------------------------------------
----------// HEADER //----------------
--------------------------------------
--[[
 * REALIVE: Reaper Setup for a Complete Live Playback Engine
 * ReaScript Name: Realive_ProjectTabsList_Compare.lua
 * Description: Project Tabs List Compare with last Saved One
 * Instructions:
 * Author: Alex Paquette, Thanks to Claude Fillion for the Large contribution
 * Repository: 
 * Repository URI:
 * File URI:
 * Licence: GPL v3
 * Forum Thread:
 * Forum Thread URI: https://forum.cockos.com/showthread.php?p=1854775#post1854775
 * REAPER: 5
 * Extensions: SWS/S&M
 * Version: 2.00
--]]
 
--[[
 * Changelog:
 * v1.0 (2019-06-02)
	+ Initial Release
--]]


--------------------------------------
----------// VARIABLES //-------------
--------------------------------------

local reaper = reaper  -------// Performance Enhancement //----------
local EXT_SECTION = 'ProjectTabs_Reaper_list'
local EXT_SECTION_PLAYLIST = 'ProjectTabs_Realive_list'
local debug = false

















-----// gmem Variables //------------------------------
local gmemSect = 'Realive_Gmem'
local gmem_idx_PlaylistState = 11
local gmem_idx_Management = 12
local gmem_idx_PlaylistState_Clean = 32
local gmem_idx_PlaylistCount_Reaper = 30
local gmem_idx_PlaylistCount_Realive = 31
local gmemPlaylist_SaveRequest = 1 
local gmemPlaylist_SaveRefused = 2
local gmemPlaylist_Initialize = 3
local gmemPlaylist_RealiveListItem_Remove = 4
local gmemPlaylist_RealiveListItem_Add = 5
local gmemPlaylist_RealiveListItem_Update = 6
local gmemPlaylist_ProjectTabs_CleanStatus = 9
local gmem_idxRead_Mngmt = reaper.gmem_read(gmem_idx_Management)











-----------------------------------------------------------
-----// DEBUG FUNCTION //----------------------------------
-----------------------------------------------------------
if debug then reaper.ShowConsoleMsg("") end
function Msg(value)
	if debug then
    	reaper.ShowConsoleMsg(tostring(value) .. "\n")
	end
end





-----------------------------------------------------------
-----// FUNCTIONS //---------------------------------------
-----------------------------------------------------------
function Playlist_CountProjectTabs()
  local ProjCount=-1
  local Aretval="t"
  while Aretval~=nil do
    local Aretval, Aprojfn = reaper.EnumProjects(ProjCount+1, "")
    if Aretval~=nil then ProjCount=ProjCount+1
    else break
    end
  end
  return ProjCount+1
end
  ---------------------------------------------------















-----------------------------------------------------------
-----// Realive List Management //-------------------------
-----------------------------------------------------------
function makeKey(i)
	return string.format('project%d', i)
end



function enum_RealivePlaylist()
	local i = 1
		return function()
		local key = makeKey(i)
			i = i + 1
		if reaper.HasExtState(EXT_SECTION_PLAYLIST, key) then
		return key
		end
	end
end


function get_RealivePlaylist()
	local Realive_list = {}
	for Realive_key in enum_RealivePlaylist() do
		local Realive_projfn = reaper.GetExtState(EXT_SECTION_PLAYLIST, Realive_key)
		table.insert(Realive_list, Realive_projfn)
		end
	return Realive_list
end



-----------------------------------------------------------
-----// SAVE RPL FUNCTION //-------------------------------
-----------------------------------------------------------
function SaveRPL()
	local out_str = ''
	local targetPath = ''
	if reaper.HasExtState('Realive_PlaylistFolder', 'lastPath') then
		lastPath = reaper.GetExtState('Realive_PlaylistFolder', 'lastPath')
	end
	if reaper.HasExtState('Realive_PlaylistFolder', 'defaultPath') then
		defaultPath = reaper.GetExtState('Realive_PlaylistFolder', 'defaultPath')
	end
	if lastPath ~= '' then targetPath = lastPath
	elseif defaultPath ~= '' then targetPath = defaultPath
	end
	local unsavedConfirm = 0
	local playlist = get_RealivePlaylist()
	
 	local projcnt = Playlist_CountProjectTabs()
	local UnsavedProj_cnt = 0
    for i = 1, projcnt do
      local retval, projfn=  reaper.EnumProjects( i-1, '' )
	  if projfn =='' then UnsavedProj_cnt = UnsavedProj_cnt+1 end
	  Msg('projfn: '..projfn)
    end
    Msg('UnsavedProject: '..UnsavedProj_cnt)
    if UnsavedProj_cnt > 0 then
		unsavedConfirm = reaper.ShowMessageBox("Your list contains project(s) that have no name. They will not be saved in the playlist.  Do you still want to proceed? ", 'Warning', 4) -- Yes = 6, No = 7, Cancel = 2
		Msg('unsavedConfirm: '..unsavedConfirm)
		if unsavedConfirm ~= 6 then return end
	end

	local SaveDialogAnswer, saving_folder = reaper.JS_Dialog_BrowseForSaveFile('Save RPL', targetPath, '', 'Reaper Playlist files (.RPL)\0*.RPL\0\0')
	Msg('SaveDialogAnswer: '..SaveDialogAnswer)
	if SaveDialogAnswer == 1 then -- if a file was selected
		extst_path = string.match(saving_folder, ".+/")
		reaper.SetExtState('Realive_PlaylistFolder', 'lastPath', extst_path, false)
		Msg('path: '..extst_path)
		for i = 1, #playlist do 
			out_str = out_str..playlist[i]..'\n' 
		end                          
		local f = io.open(saving_folder, 'w')                          
		f:write(out_str)
		f:close()
		reaper.gmem_write(gmem_idx_Management, gmemPlaylist_ProjectTabs_CleanStatus)
		return true
	else 
		return false
	end
end




------------------------------------------
---------// RUN FUNCTION  //--------------
------------------------------------------

function run()
	SaveRPL()
end


------------------------------------------
---------// RUNTIME  //-------------------
------------------------------------------
reaper.gmem_attach(gmemSect)
run()