if os.getenv("LOCAL_LUA_DEBUGGER_VSCODE") == "1" then
    require "lldebugger".start()
end

local util   = require "util"
local launch = require "launch"

local iui = require "lib.iui"
local backend = require "lib.lovr-iui"

-- modify for nested lovr path for api
iui.resourcePath = "lovr/" .. iui.resourcePath
backend.resourcePath = "lovr/" .. backend.resourcePath
api.iui = iui
api.backend = backend
-- decorate api
api.protocol.http = require('http')
local ecs = api.ecs
ecs.filterDraw   = ecs.requireAll('drawthread')
ecs.filterUpdate = ecs.requireAll('updatethread')


-- ecs systems
local interactionsUpdater
local renderer

--- @type Texture
local envTex

--- @type LovrIUIWorldWindow
local mainWindow

function lovr.load()
    if launch.mode == "desktop" then
        backend.mouse = require "lib.lovr-mouse"

        lovr.system.setKeyRepeat(true)
    end

    iui.load(backend)

    api.exec( api.ext, "load")

    if iui.idiom == "vr" then
        lovr.headset.setPassthrough("opaque")

        mainWindow = backend.worldWindow.new()
        api.mainWindow = mainWindow
    end
end

function lovr.update(dt)
    
    ecs.update( api.world, dt, ecs.filterUpdate )

    iui.beginFrame(dt)

    if iui.idiom == "desktop" then
        -- In desktop mode, we use IUI's standard window API to fill the screen.
        iui.beginWindow(lovr.system.getWindowDimensions())

        api.exec( api.ext, "update", dt)

        iui.endWindow()

    elseif iui.idiom == "vr" then
        -- In VR mode, we have access to the backend's `LovrIUIWorldWindow`
        -- class, which handles windowing in world-space.
        if mainWindow:beginFrame() then
            iui.beginWindow(mainWindow.w, mainWindow.h)

            api.exec( api.ext, "update", dt)

            iui.endWindow()

            mainWindow:endFrame()
        end
    end

    iui.endFrame()
end

function lovr.draw(pass)
    if iui.idiom == "desktop" then
        backend.graphics.pass = pass

        iui.draw()
    end
    if api.iui.idiom == "vr" then
      pass:setClear(0.5, 0.5, 0.5)
    end

    api.exec(api.ext, "draw",pass)
    ecs.update( api.world, pass, ecs.filterDraw )

     -- Dot
    if selectedBox then
      pass:setColor(0, 0, 1)
      pass:sphere(hitpoint, .01)
    end
    
    -- Laser pointer
    local hand = vec3(lovr.headset.getPosition('hand/left/point'))
    local direction = quat(lovr.headset.getOrientation('hand/left/point')):direction()
    pass:setColor(1, 1, 1)
    pass:line(hand, selectedBox and hitpoint or (hand + direction * 50))

    if api.mainWindow then
      api.mainWindow:draw(pass)
    end
    return false
end

function lovr.recenter()
    if iui.idiom == "vr" then
        mainWindow:recenter()
    end
end

if launch.mode == "desktop" then
    function lovr.mousemoved(x, y, dx, dy)
        backend.mousemoved(x, y, dx, dy)
        interactionsUpdater['mouse']['moved'] = {x=x, y=y, button=button}
    end

    function lovr.mousepressed(x, y, button)
        backend.mousepressed(x, y, button)
        interactionsUpdater['mouse']['pressed'] = {x=x, y=y, button=button}
    end

    function lovr.mousereleased(x, y, button)
        backend.mousereleased(x, y, button)
        interactionsUpdater['mouse']['released'] = {x=x, y=y, button=button}
        print("mouserelease")
    end

    function lovr.wheelmoved(x, y)
        backend.wheelmoved(x, y)
        interactionsUpdater['mouse']['wheel'] = {x=x, y=y}
    end

    function lovr.keypressed(key, scancode, isRepeat)
        backend.keypressed(key, scancode, isRepeat)
    end

    function lovr.keyreleased(key, scancode)
        backend.keyreleased(key, scancode)
    end

    function lovr.textinput(text)
        backend.textinput(text)
    end
end

local initECS = function(ecs)
  -- lovr.draw => ecs.draw (render-logic thread)
  renderer = ecs.processingSystem()
  renderer.filter        = ecs.requireAll('model') 
  renderer.drawthread = true
  function renderer:process(obj, pass)
    if obj.model ~= nil and obj.root ~= nil then 
      pass:setMaterial()
      pass:setCullMode('none')
      pass:draw(
        obj['model'], 
        obj['x'] or 0, 
        obj['y'] or 0,
        obj['z'] or 0, 
        1, 0, 1, 0, 0, 1)
    end
  end
  ecs.addSystem( api.world, renderer )

end

function initInteractions(ecs)

  ecs.worldPhysics = lovr.physics.newWorld(0, 0, 0)
  interactionsUpdater = ecs.processingSystem()
  interactionsUpdater.updatethread = true 
  interactionsUpdater.filter = ecs.requireAll('collider')
  -- collider vars
  interactionsUpdater.mouse = { released = false}
  interactionsUpdater.hitpoint = lovr.math.newVec3()
  interactionsUpdater.selectedBox = nil


  function interactionsUpdater:process(obj, dt)
    ecs.worldPhysics:update(dt)

    local ox, oy, oz = lovr.headset.getPosition('hand/left/point')
    local dx, dy, dz = quat(lovr.headset.getOrientation('hand/left/point')):direction():mul(50):unpack()
    local collider, shape, x, y, z = ecs.worldPhysics:raycast(ox, oy, oz, ox + dx, oy + dy, oz + dz)

    if collider then
      if lovr.headset.isDown(hand, 'trigger') then
        local node = collider:getUserData()
        selectedBox = collider
        hitpoint:set(x, y, z)
        print( "collide with " .. node['name'] .. " => " .. node['extras']['href'] )
        print("buttondown")
      end
      if lovr.headset.wasReleased(hand, 'trigger') or interactionsUpdater['mouse']['released'] then
        print('click!')
      end
    end
    -- reset mouse
    mouse['released'] = false
    mouse['pressed'] = false
  end
  ecs.addSystem( api.world, interactionsUpdater )
end

initECS(api.ecs)
initInteractions(api.ecs)