(local pxl8 (require :pxl8))
(local effects (require :pxl8.effects))
(local net (require :pxl8.net))
(local shader (require :pxl8.shader))

(local colormap (require :mod.colormap))
(local entities (require :mod.entities))
(local menu (require :mod.menu))
(local palette (require :mod.palette))
(local sky (require :mod.sky))
(local textures (require :mod.textures))

(local bob-amount 4.0)
(local bob-speed 8.0)
(local cam-smoothing 0.25)
(local ceiling-height 120)
(local chunk-size 64)
(local cursor-sensitivity 0.010)
(local gravity 600)
(local grid-size 64)
(local jump-velocity 180)
(local land-recovery-speed 20)
(local land-squash-amount -4)
(local max-pitch 1.5)
(local move-speed 200)
(local player-eye-height 64)
(local player-height 72)
(local player-radius 12)
(local step-height 24)
(local turn-speed 4.0)

(var auto-run-cancel-key nil)
(var auto-run? false)
(var bob-time 0)
(var cam-pitch 0)
(var cam-x 416)
(var cam-y 0)
(var cam-yaw 0)
(var cam-z 416)
(var camera nil)
(var ceiling-tex nil)
(var floor-tex nil)
(var fps-avg 0)
(var fps-sample-count 0)
(var grounded true)
(var land-squash 0)
(var last-dt 0.016)
(var light-time 0)
(var lights nil)
(var bsp-materials-setup false)
(var network nil)
(var portal-cooldown 0)
(var real-time 0)
(var smooth-cam-x 416)
(var smooth-cam-z 416)
(var vel-y 0)
(var trim-tex nil)
(var wall-tex nil)
(var world nil)

(local cursor-look? true)
(local MOSS_COLOR 200)
(local PLASTER_COLOR 16)
(local STONE_FLOOR_START 37)
(local STONE_WALL_START 2)
(local WOOD_COLOR 88)

(fn find-floor [x y z in-bsp]
  (if (not world)
      0
      (if in-bsp
          0
          (let [start-y (math.max (+ y 64) 256)
                ray (world:ray x start-y z x (- y 1000) z)]
            (if ray.hit
                (+ ray.point.y 1)
                128)))))

(fn find-ceiling [x y z max-height]
  (if (not world)
      nil
      (let [ray (world:ray x (+ y 1) z x (+ y max-height) z)]
        (if ray.hit
            (- ray.point.y 1)
            nil))))

(fn preload []
  (when (not network)
    (set network (net.get))
    (when network
      (network:spawn cam-x cam-y cam-z cam-yaw cam-pitch)))
  (when (not world)
    (set world (pxl8.get_world))
    (when world
      (world:init_local_player cam-x cam-y cam-z))))

(fn is-connected []
  (and network (network:connected)))

(fn is-ready []
  (if (not world)
      false
      (let [chunk (world:active_chunk)]
        (and chunk (chunk:ready)))))

(fn init []
  (pxl8.set_relative_mouse_mode true)
  (pxl8.set_palette palette 256)
  (pxl8.set_colormap colormap 16384)
  (for [i 0 7]
    (let [t (/ i 7)
          r 0xFF
          g (math.floor (+ 0x60 (* t (- 0xE0 0x60))))
          b (math.floor (+ 0x10 (* t (- 0x80 0x10))))]
      (pxl8.set_palette_rgb (+ entities.FIREBALL_COLOR i) r g b)))
  (pxl8.set_palette_rgb (- entities.FIREBALL_COLOR 1) 0xFF 0x20 0x10)
  (sky.reset-gradient)
  (sky.update-gradient 1 2 6 6 10 18)
  (pxl8.update_palette_deps)

  (when (not camera)
    (set camera (pxl8.create_camera_3d)))
  (when (not lights)
    (set lights (pxl8.create_lights)))

  (entities.init textures)

  (sky.generate-stars 12345)

  (preload)

  (when (not ceiling-tex)
    (set ceiling-tex (textures.plaster-wall 66666 PLASTER_COLOR)))
  (when (not floor-tex)
    (set floor-tex (textures.wood-planks 44444 WOOD_COLOR)))
  (when (not trim-tex)
    (set trim-tex (textures.wood-trim 77777 WOOD_COLOR)))
  (when (not wall-tex)
    (set wall-tex (textures.cobble-timber 55555 STONE_WALL_START MOSS_COLOR WOOD_COLOR)))

  )

(fn setup-materials []
  (when (and world (not bsp-materials-setup) ceiling-tex floor-tex trim-tex wall-tex)
    (let [chunk (world:active_chunk)]
      (when (and chunk (chunk:ready))
        (let [ceiling-mat (pxl8.create_material {:texture ceiling-tex})
              floor-mat (pxl8.create_material {:texture floor-tex :lighting true})
              trim-mat (pxl8.create_material {:texture trim-tex :lighting true})
              wall-mat (pxl8.create_material {:texture wall-tex :lighting true})]

          (world:set_bsp_material 0 floor-mat)
          (world:set_bsp_material 1 wall-mat)
          (world:set_bsp_material 2 ceiling-mat)
          (world:set_bsp_material 3 trim-mat)
          (set bsp-materials-setup true))))))

(fn sample-input []
  (var move-forward 0)
  (var move-right 0)

  (when (pxl8.key_pressed "`")
    (set auto-run? (not auto-run?))
    (when (and auto-run? (pxl8.key_down "w"))
      (set auto-run-cancel-key "w")))
  (when (and auto-run? (not auto-run-cancel-key) (or (pxl8.key_down "w") (pxl8.key_down "s")))
    (set auto-run? false)
    (when (pxl8.key_down "s")
      (set auto-run-cancel-key "s")))
  (when (and auto-run-cancel-key (not (pxl8.key_down auto-run-cancel-key)))
    (set auto-run-cancel-key nil))

  (when (or (pxl8.key_down "w") auto-run?)
    (set move-forward (+ move-forward 1)))
  (when (and (pxl8.key_down "s") (not= auto-run-cancel-key "s"))
    (set move-forward (- move-forward 1)))
  (when (pxl8.key_down "a")
    (set move-right (- move-right 1)))
  (when (pxl8.key_down "d")
    (set move-right (+ move-right 1)))

  {:move_x move-right
   :move_y move-forward
   :look_dx (pxl8.mouse_dx)
   :look_dy (pxl8.mouse_dy)})

(fn update [dt]
  (set last-dt dt)
  (let [fps (pxl8.get_fps)]
    (set fps-sample-count (+ fps-sample-count 1))
    (set fps-avg (+ (* fps-avg (/ (- fps-sample-count 1) fps-sample-count))
                    (/ fps fps-sample-count)))
    (when (>= fps-sample-count 120)
      (set fps-sample-count 0)
      (set fps-avg 0)))

  (setup-materials)

  (when (> portal-cooldown 0)
    (set portal-cooldown (- portal-cooldown dt)))

  (when (and network (<= portal-cooldown 0))
    (let [chunk (world:active_chunk)
          in-bsp (not= chunk nil)
          (door-x door-z) (entities.get-door-position)
          door-radius (entities.get-door-radius)
          dist-to-door (math.sqrt (+ (* (- cam-x door-x) (- cam-x door-x))
                                     (* (- cam-z door-z) (- cam-z door-z))))]
      (when (< dist-to-door door-radius)
        (if in-bsp
            (do
              (pxl8.info "Exiting through door...")
              (let [exit-x (+ door-x 50)
                    exit-z door-z
                    exit-y 200]
                (network:exit_chunk exit-x exit-y exit-z)
                (set cam-x exit-x)
                (set cam-z exit-z)
                (set cam-y exit-y))
              (set vel-y 0)
              (set grounded false)
              (set smooth-cam-x cam-x)
              (set smooth-cam-z cam-z)
              (set bsp-materials-setup false)
              (set portal-cooldown 2.0))
            (do
              (pxl8.info "Entering through door...")
              (network:enter_chunk 1)
              (set cam-x 416)
              (set cam-z 416)
              (set cam-y 0)
              (set vel-y 0)
              (set grounded true)
              (set smooth-cam-x 416)
              (set smooth-cam-z 416)
              (set portal-cooldown 2.0))))))

  (let [chunk (world:active_chunk)
        chunk-id (if network (network:chunk_id) -1)
        expecting-bsp (> chunk-id 0)
        voxel-space (and (not chunk) (= chunk-id 0))
        ready (or voxel-space (and chunk (chunk:ready)))]
  (when ready
    (let [input (sample-input)
          grid-max (if voxel-space 100000 (* grid-size chunk-size))
          movement-yaw cam-yaw]

      (let [player (world:local_player)]
        (when player
          (set cam-x player.pos.x)
          (set cam-y player.pos.y)
          (set cam-z player.pos.z)
          (set cam-yaw player.yaw)
          (set cam-pitch player.pitch)))

      (when (and voxel-space grounded)
        (let [floor-y (find-floor cam-x cam-y cam-z false)
              height-diff (- floor-y cam-y)]
          (if (and (>= height-diff (- step-height)) (<= height-diff step-height))
              (let [lerp-speed 0.3
                    smooth-y (+ (* cam-y (- 1 lerp-speed)) (* floor-y lerp-speed))]
                (set cam-y smooth-y))
              (when (< height-diff (- step-height))
                (set grounded false)))))

      (set smooth-cam-x (+ (* smooth-cam-x (- 1 cam-smoothing)) (* cam-x cam-smoothing)))
      (set smooth-cam-z (+ (* smooth-cam-z (- 1 cam-smoothing)) (* cam-z cam-smoothing)))

      (when (and (pxl8.key_pressed "space") grounded)
        (set vel-y jump-velocity)
        (set grounded false))

      (when (or (not grounded) (not= vel-y 0))
        (set vel-y (- vel-y (* gravity dt)))

        (if (> vel-y 0)
            (let [new-y (+ cam-y (* vel-y dt))
                  head-y (+ new-y player-height)
                  ceiling-y (if voxel-space
                                (find-ceiling cam-x cam-y cam-z 200)
                                ceiling-height)]
              (if (and ceiling-y (>= head-y ceiling-y))
                  (do
                    (set cam-y (- ceiling-y player-height))
                    (set vel-y 0))
                  (set cam-y new-y)))
            (let [new-y (+ cam-y (* vel-y dt))
                  floor-y (find-floor cam-x cam-y cam-z (not voxel-space))]
              (if (<= new-y floor-y)
                  (do
                    (set cam-y floor-y)
                    (set land-squash land-squash-amount)
                    (set vel-y 0)
                    (set grounded true))
                  (do
                    (set cam-y new-y)
                    (set grounded false))))))

      (when (< land-squash 0)
        (set land-squash (math.min 0 (+ land-squash (* land-recovery-speed dt)))))

      (let [moving (or (not= input.move_x 0) (not= input.move_y 0))]
        (if (and moving grounded)
            (set bob-time (+ bob-time (* dt bob-speed)))
            (let [target-phase (* (math.floor (/ bob-time math.pi)) math.pi)]
              (set bob-time (+ (* bob-time 0.8) (* target-phase 0.2))))))

      (set light-time (+ light-time (* dt 0.5)))
      (set real-time (+ real-time dt))))))

(fn frame []
  (pxl8.clear 1)

  (when (not camera)
    (pxl8.error "camera is nil!"))

  (when (not world)
    (pxl8.error "world is nil!"))

  (let [chunk (when world (world:active_chunk))
        expecting-bsp (and network (> (network:chunk_id) 0))
        voxel-space (and world (not chunk) (not expecting-bsp))
        ready (or voxel-space (and chunk (chunk:ready)))]

  (when (and world (not ready))
    (pxl8.text "Waiting for world data..." 5 30 12))

  (when (and camera world ready)
    (let [bob-offset (* (math.sin bob-time) bob-amount)
          eye-y (+ cam-y player-eye-height bob-offset land-squash)
          forward-x (- (math.sin cam-yaw))
          forward-z (- (math.cos cam-yaw))
          target-x (+ smooth-cam-x forward-x)
          target-y (+ eye-y (math.sin cam-pitch))
          target-z (+ smooth-cam-z forward-z)
          aspect (/ (pxl8.get_width) (pxl8.get_height))]

      (camera:lookat [smooth-cam-x eye-y smooth-cam-z]
                     [target-x target-y target-z]
                     [0 1 0])
      (camera:set_perspective 1.047 aspect 1.0 4096.0)

      (let [light-x (+ 384 (* 50 (math.cos light-time)))
            light-z (+ 324 (* 50 (math.sin light-time)))
            light-y 80
            phase (+ (* light-x 0.01) 1.7)
            f1 (* 0.08 (math.sin (+ (* real-time 2.5) phase)))
            f2 (* 0.05 (math.sin (+ (* real-time 4.1) (* phase 0.7))))
            f3 (* 0.03 (math.sin (+ (* real-time 7.3) (* phase 1.2))))
            flicker (+ 0.92 f1 f2 f3)
            light-intensity (math.floor (math.max 0 (math.min 255 (* 255 flicker))))
            r1 (* 0.06 (math.sin (+ (* real-time 1.8) (* phase 0.5))))
            r2 (* 0.04 (math.sin (+ (* real-time 3.2) phase)))
            light-radius (* 150 (+ 0.95 r1 r2))]
        (lights:clear)
        (lights:add light-x light-y light-z 0xFF8C32 light-intensity light-radius)
        (pxl8.begin_frame_3d camera lights {
          :ambient 30
          :fog_density 0.0
          :celestial_dir [0.5 -0.8 0.3]
          :celestial_intensity 0.5})
        (pxl8.clear_depth)

        (sky.update-gradient 1 2 6 6 10 18)
        (sky.render smooth-cam-x eye-y smooth-cam-z (menu.is-wireframe))
        (pxl8.clear_depth)

        (world:set_wireframe (menu.is-wireframe))
        (world:render [smooth-cam-x eye-y smooth-cam-z])

        (when chunk
          (entities.render-fireball light-x light-y light-z (menu.is-wireframe)))

        (entities.render-door (menu.is-wireframe) (if voxel-space 128 0))

        (pxl8.end_frame_3d))

        ;; TODO: shader needs to run at present time, not mid-frame
        ;; (shader.begin_frame)
        ;; (shader.run shader.presets.light_with_fog
        ;;             {:fog_r 6 :fog_g 6 :fog_b 12
        ;;              :fog_start 0.1 :fog_end 0.85})

      (sky.render-stars smooth-cam-x eye-y smooth-cam-z 1.0 last-dt)

      (let [cx (/ (pxl8.get_width) 2)
            cy (/ (pxl8.get_height) 2)
            crosshair-size 4
            crosshair-color 240
            text-color 251]
        (pxl8.line (- cx crosshair-size) cy (+ cx crosshair-size) cy crosshair-color)
        (pxl8.line cx (- cy crosshair-size) cx (+ cy crosshair-size) crosshair-color)

        (pxl8.text (.. "fps: " (string.format "%.0f" fps-avg)) 5 5 text-color)
        (pxl8.text (.. "pos: " (string.format "%.0f" cam-x) ","
                       (string.format "%.0f" cam-y) ","
                       (string.format "%.0f" cam-z)) 5 15 text-color))))))

{:preload preload
 :is-connected is-connected
 :is-ready is-ready
 :init init
 :update update
 :frame frame}