local fs = require("filesystem")

local FileTree = {}
function FileTree:new(iterator)
    local file_tree = {
        iterator = iterator,
        filters = {}
    }
    setmetatable(file_tree, self)
    self.__index = self
    return file_tree
end

function directory(path_or_dir)
    if type(path_or_dir) == "string" then
        return FileTree:new(fs.directory_source(path_or_dir))
    end
    if path_or_dir.path ~= nil then
        return FileTree:new(fs.directory_source(path_or_dir.path))
    end
    error("Invalid type for directory")
end

function FileTree:filter(filter_fn)
    table.insert(self.filters, filter_fn)
    return self
end

function FileTree:__call()
    local next = self.iterator()
    if next == nil then
        return nil
    end

    for _,filter in  pairs(self.filters) do
        if (not filter(next)) then
            return self()
        end
    end
    return next
end

function is_dir(entry)
    return entry:is_dir()
end

function is_file(entry)
    return entry:is_dir()
end

function starts_with(prefix)
    return function(entry)
        return entry.path:find("^"..prefix)
    end
end

function contains(infix)
    return function(entry)
        return entry.path:find(infix)
    end
end

function does_not(predicate)
    return function(...) return not predicate(...) end
end

function zip(source)
    print("would zip")
    for entry in source do
        print(entry.path)
    end
end

local comic_dir = directory("/Users/kinch/Desktop/Rebuild World")
comic_dir:filter(is_dir)

for chapter_dir in comic_dir do
    zip(directory(chapter_dir):filter(does_not(contains("._"))))
end