require "serialize"

local Monitor = Class()
function Monitor:init(name, a)
    self.name = name
    self.begin = a.addr
    self.len = a.type
    self.once = false
    self.old_bytes = {}
    self.modified = {}
    self.dirty = false
end

function Monitor:read()
    local raw = mainmemory.readbyterange(self.begin, self.len)
    local bytes = {}
    for k, v in pairs(raw) do
        bytes[k] = v
    end
    return bytes
end

function Monitor:diff()
    local bytes = self:read()
    local old_bytes = self.old_bytes
    if self.once then
        for i, v in pairs(bytes) do
            local x = v
            local x1 = old_bytes[i]
            if x ~= x1 then
                self:mark(i, x, x1)
            end
        end
    end
    self.old_bytes = bytes
    self.once = true
end

function Monitor:load(fn)
    self.modified = deserialize(fn) or {}
    self.dirty = false
    self.fn = fn
end

function Monitor:save(fn)
    if self.dirty then
        serialize(fn or self.fn, self.modified)
        self.dirty = false
    end
end

return Monitor