-- Loader from Saver
-- by Stefan Ihringer <stefan@bildfehler.de>
--
-- Creates a loader for the selected saver.
-- Copies the Path of a saver to a loader if both are selected.
--
-- version 0.7, 2013-03-23: don't force file numbers for mov and avi files
-- version 0.6, 2013-03-16: a bug prevented the script from working with path maps that didn't contain a backslash
-- version 0.5, 2012-04-11: no longer uses Lock() and Unlock() since these commands clear caches
-- version 0.4, 2011-11-11: now uses eyeon.MoveClip to fix a problem with clip positioning
-- version 0.3, 2010-11-11: optionally colors the new loader
-- version 0.2, 2010-10-09: works with path mappings
--                          detects first frame of rendered sequence amd shifts loader's global in to match saver
-- version 0.1, 2010-09-25: initial release
--
-- ideas for improvement:
-- * display dialog box if more than one saver is selected?

-- comment this line if you don't want the loader's color changed
COLORED = {bg = {R=60/255, G=120/255, B=180/255}, fg = {R=1, G=1, B=1}}

---------------
-- helper function to update a loader with a new file name and global in frame
function update_loader(ld, new_clip, new_in)
	ld.Clip[TIME_UNDEFINED] = ""
	ld.Clip[TIME_UNDEFINED] = new_clip
	ld:SetAttrs({TOOLB_PassThrough = true})
	ld:SetAttrs({TOOLB_PassThrough = false})
	if new_in ~= nil then
		eyeon.MoveClip(ld, comp:GetAttrs().COMPN_GlobalStart, new_in)
	end
end

-- helper function to scan a file sequence and return its smallest frame number
function getFirstFrameOfSequence(clip)
	local smallest = nil
	local fp = eyeon.parseFilename(composition:MapPath(clip))
	local dirlist = eyeon.readdir(fp.Path .. fp.CleanName .. "*" .. fp.Extension)
	for i, f in ipairs(dirlist) do
		if not f.IsDir then
			-- find smallest frame number
			string.gsub(f.Name, "(%d+)"..fp.Extension.."$", function(n) if smallest == nil or tonumber(n) < smallest then smallest = tonumber(n) end end)
		end
	end
	return smallest
end
------------------------------------------------


if composition == nil then
	composition:GetFrameList()[1]:SwitchMainView('ConsoleView') 
	print("This is a composition script, it should be run from within Fusion.")
	exit()
end

local savers = composition:GetToolList(true, "Saver")
local loaders = composition:GetToolList(true, "Loader")

if savers == nil or #savers < 1 then
	composition:GetFrameList()[1]:SwitchMainView('ConsoleView') 
	print("Please select a saver or a saver and a loader first.")
	exit()
end

local the_saver = savers[1]

-- saver needs its path set
local clipname = the_saver.Clip[TIME_UNDEFINED]
if clipname == "" then
	composition:GetFrameList()[1]:SwitchMainView('ConsoleView') 
	print("The saver needs to have an output filename.")
	exit()
end

-- for eyeon.parseFilename to work, there has to be a backslash after the path map entry.
-- let's add one if it is missing:
clipname = clipname:gsub(":([^\\])", ":\\%1", 1)
-- if clipname doesn't include a frame counter, add one to look for
local fp = eyeon.parseFilename(clipname)

if fp.Extension:lower() ~= ".avi" and fp.Extension:lower() ~= ".mov" then
	dump(fp)
	if fp.SNum == "" then
		clipname = fp.Path .. fp.CleanName .. "0000" .. fp.Extension
		fp.SNum = "0000"
		fp.Number = 0
		fp.Padding = 4
	end

	-- calculate correct in point for the loader, so the clip will be in sync with the saver
	-- instead of being placed at frame 0 (or whatever is set in the preferences).
	-- First, detect the first frame number of the rendered sequence (nil = not rendered or other error occured):
	local firstframe = getFirstFrameOfSequence(clipname)
	if firstframe ~= nil then
		-- build new clip name with correct frame number
		clipname = fp.Path .. fp.CleanName .. string.format("%0" .. fp.Padding .. "d", firstframe) .. fp.Extension
		--print("Rendered sequence starts at frame "..firstframe)
		--print("new clip name: ", clipname)
	end

	-- Next, do the frame offset calculation
	local globalin = firstframe
	if globalin ~= nil then
		globalin = globalin - the_saver.SequenceStartFrame[TIME_UNDEFINED]
		if the_saver.SetSequenceStart[TIME_UNDEFINED] == 1 then
			globalin = globalin + composition:GetAttrs().COMPN_GlobalStart
		end
	end
else
	-- mov or avi files:
	globalin = composition:GetAttrs().COMPN_GlobalStart
	firstframe = 0
end

composition:StartUndo("Loader from Saver script")

if loaders == nil or #loaders < 1 then
	-- no loader selected: create a new one next to the selected saver
	local posX, posY = composition.CurrentFrame.FlowView:GetPos(the_saver)

	-- disable file requester popup
	autobrowse = fusion:GetPrefs("Global.UserInterface.AutoClipBrowse")
	fusion:SetPrefs("Global.UserInterface.AutoClipBrowse", false)
	local new_loader = composition:AddTool("Loader", posX + 2, posY)
	print("Created Loader from " .. the_saver:GetAttrs()['TOOLS_Name'])
	if firstframe ~= nil and globalin ~= firstframe then
		print("First frame at ".. globalin)
	end
	fusion:SetPrefs("Global.UserInterface.AutoClipBrowse", autobrowse)

	update_loader(new_loader, clipname, globalin)
	new_loader:SetAttrs({TOOLS_Name = "Loader_" .. the_saver:GetAttrs()['TOOLS_Name'], TOOLB_NameSet = true})

	-- set color?
	if COLORED ~= nil then
		new_loader.TileColor = COLORED.bg
		new_loader.TextColor = COLORED.fg
	end
	composition:SetActiveTool(new_loader)
else
	-- update all selected loaders
	for n, the_loader in ipairs(loaders) do
		update_loader(the_loader, clipname, globalin)
		-- set color?
		if COLORED ~= nil then
			the_loader.TileColor = COLORED.bg
			the_loader.TextColor = COLORED.fg
		end
		print("Updated " .. the_loader:GetAttrs()['TOOLS_Name'] .. " to " .. clipname)
		if firstframe ~= nil and globalin ~= firstframe then
			print("First frame at ".. globalin)
		end
	end
end

composition:EndUndo(true)