Merges Tachiyomi CBZ chapters. Requires Lua 5.1

tachiyomi_cbz_merger.lua

require("zip")

-- credits: https://stackoverflow.com/questions/2829175/how-to-extract-files-from-a-zip-file-using-lua
function extract(zipPath, zipFilename, destinationPath)
	local zfile, err = zip.open(zipPath .. zipFilename)
	
	-- iterate through each file insize the zip file
	for file in zfile:files() do
		local currFile, err = zfile:open(file.filename)
		local currFileContents = currFile:read("*a") -- read entire contents of current file
		local hBinaryOutput = io.open(destinationPath .. file.filename, "wb")
	
		-- write current file inside zip to a file outside zip
		if(hBinaryOutput)then
			hBinaryOutput:write(currFileContents)
			hBinaryOutput:close()
		end
		currFile:close()
	end
	
	zfile:close()
end

os.execute("if not exist \"final\" mkdir final")

local files = io.popen('dir /B')
local list = { }

local count = nil
for filename in files:lines() do
	if filename:find('cbz') then
		local zfile = zip.open(filename)
		if zfile then
			local pngs = {}
			for png in zfile:files() do
				if png.filename:find("png") then
					if count == nil then
						count = tonumber(png.filename:match("%d+"))
					end

					pngs[png.filename] = tostring(count) .. ".png"
					count = count + 1
				end
			end

			list[filename] = pngs
			zfile:close()
		end
	end
end

for filename, pngs in pairs(list) do
	extract("", filename, "final\\")
	for old, new in pairs(pngs) do
		os.rename("final\\" .. old, "final\\" .. new)
	end
end