viewcontroller_closure.lua

local objc = require 'objc'
local ffi = require 'ffi'

local count = 0
function objc.GenerateClass(super, ...)
    super = super or 'NSObject'
    count = count + 1
    local name = 'EQEAPP_'..count..super

    if ... then
        objc.class(name, super..'<'..table.concat({...}, ',')..'>')
    else
         objc.class(name, super)
    end

    return objc[name]
end
local key = ffi.new('int[1]')
function objc.ref(obj, set)
    -- associated objects should be objc
    -- objects. but this works, so w/e
    assert(set)
    local ref = REF(set, true)
    local v = ffi.cast('int *', C.malloc(ffi.sizeof('int')))
    v[0] = ref
    C.objc_setAssociatedObject(obj, key, ffi.cast('id', v), C.OBJC_ASSOCIATION_ASSIGN)
end
function objc.unref(obj)
    local v = ffi.cast('int *', C.objc_getAssociatedObject(obj, key))
    if not v then error('obj not found') end
    REF(v[0], false)
    C.objc_setAssociatedObject(obj, key, nil, C.OBJC_ASSOCIATION_ASSIGN)
    C.free(v)
end

function objc.getref(obj)
    local v = ffi.cast('int *', C.objc_getAssociatedObject(obj, key))
    return v and REF(v[0], nil) or nil
end

local vc_class = objc.GenerateClass('UIViewController')
local function dealloc(m)
    local self = objc.getref(m)
    for _,v in pairs(self.i) do
        local type = type(v)
        if type == 'cdata' then
            v:release()
        elseif type == 'table' and v.m then
            v.m:release()
        end
    end
    if self.dealloc then
        self:dealloc()
    end
    objc.unref(m)
    objc.callsuper(m, 'dealloc')
end
dealloc = ffi.cast('IMP', ffi.cast('void (*)(id, SEL)', dealloc))
C.class_replaceMethod(vc_class, objc.SEL('dealloc'), dealloc, ffi.arch == 'arm64' and 'v16@0:8' or 'v8@0:4')

local function viewDidLoad(m)
    local self = objc.getref(m)
    return self.on_load(m)
end
viewDidLoad = ffi.cast('IMP', ffi.cast('void (*)(id, SEL)', viewDidLoad))
C.class_replaceMethod(vc_class, objc.SEL('viewDidLoad'), viewDidLoad, ffi.arch == 'arm64' and 'v16@0:8' or 'v8@0:4')

function VIEWCONTROLLER(callback, title)
    local self = {}
    self.i = {}
    self.m = vc_class:alloc():init()
    self.on_load = callback
    self.m:setTitle(title or '')
    objc.ref(self.m, self)
    self.m:autorelease()
    return self.m
end