// Model Viewer for lance3d
// Usage: cell run examples/modelview.ce <model_path>
// Controls: WASD orbit, Q/E zoom, R/F move target, SPACE toggle animation, 1-9 switch clip
// F1/F2/F3 - Switch style (PS1/N64/Saturn)

var io = use('fd')
var time_mod = use('time')
var lance3d = use('core')
var math = use('math/radians')

log.console(lance3d.key)

// Parse command line arguments
var model_path = args[0] || "Duck.glb"

// Camera orbit state
var cam_distance = 5
var cam_yaw = 0
var cam_pitch = 0.3
var cam_target_y = 0
var orbit_speed = 2.0
var zoom_speed = 0.5

// Model
var model = null

// Animation state
var animations = []
var current_anim = 0
var anim_time = 0
var anim_playing = true
var anim_speed = 1.0

// Current style
var style = "ps1"

// Timing
var last_time = 0

function _init() {
  log.console("lance3d Model Viewer")
  log.console("Loading: " + model_path)

  // Initialize lance3d with PS1 style
  lance3d.set_style(style)

  // Load the model
  model = lance3d.load_model(model_path)
  if (!model) {
    log.console("Error: Could not load model: " + model_path)
    $stop()
    return
  }

  log.console("Model loaded with " + text(length(model)) + " mesh(es)")

  // Get animation info
  var i = null
  animations = lance3d.anim_info(model)
  log.console("  Animations: " + text(length(animations)))
  for (i = 0; i < length(animations); i++) {
    log.console("    " + text(i) + ": " + animations[i].name + " (" + text(animations[i].duration) + "s)")
  }

  // Set up lighting
  lance3d.set_lighting({
    sun_dir: [0.5, 1.0, 0.3],
    sun_color: [1.0, 0.95, 0.9],
    ambient: [0.3, 0.3, 0.35]
  })

  last_time = time_mod.number()

  log.console("")
  log.console("Controls:")
  log.console("  WASD  - Orbit camera")
  log.console("  Q/E   - Zoom in/out")
  log.console("  R/F   - Move target up/down")
  log.console("  SPACE - Toggle animation")
  log.console("  1-9   - Switch animation clip")
  log.console("  ESC   - Exit")
  log.console("  F1    - PS1 style")
  log.console("  F2    - N64 style")
  log.console("  F3    - Saturn style")

  // Start the main loop
  frame()
}

function _update(dt) {
  var i = null
  var clip_idx = null
  var duration = null

  // Handle input for camera orbit
  if (lance3d.key('a')) {
    cam_yaw -= orbit_speed * dt
  }
  if (lance3d.key('d')) {
    cam_yaw += orbit_speed * dt
  }
  if (lance3d.key('w')) {
    cam_pitch += orbit_speed * dt
    if (cam_pitch > 1.5) cam_pitch = 1.5
  }
  if (lance3d.key('s')) {
    cam_pitch -= orbit_speed * dt
    if (cam_pitch < -1.5) cam_pitch = -1.5
  }

  // Zoom
  if (lance3d.key('q')) {
    cam_distance -= zoom_speed * dt * cam_distance
    if (cam_distance < 0.5) cam_distance = 0.5
  }
  if (lance3d.key('e')) {
    cam_distance += zoom_speed * dt * cam_distance
    if (cam_distance > 100) cam_distance = 100
  }

  // Move target up/down
  if (lance3d.key('r')) {
    cam_target_y += zoom_speed * dt
  }
  if (lance3d.key('f')) {
    cam_target_y -= zoom_speed * dt
  }

  // Exit on escape
  if (lance3d.key('escape')) {
    $stop()
  }

  // Toggle animation with space
  if (lance3d.keyp('space') && length(animations) > 0) {
    anim_playing = !anim_playing
    log.console(anim_playing ? "Animation resumed" : "Animation paused")
  }

  // Switch animation clips with number keys
  if (length(animations) > 0) {
    for (i = 1; i <= 9; i++) {
      if (lance3d.keyp(text(i))) {
        clip_idx = i - 1
        if (clip_idx < length(animations)) {
          current_anim = clip_idx
          anim_time = 0
          log.console("Playing clip " + text(clip_idx) + ": " + animations[clip_idx].name)
        }
      }
    }
  }

  // Switch platform style with F1-F3
  if (lance3d.keyp('f1')) {
    _switch_to_style("ps1")
  }
  if (lance3d.keyp('f2')) {
    _switch_to_style("n64")
  }
  if (lance3d.keyp('f3')) {
    _switch_to_style("saturn")
  }

  // Update animation time
  if (anim_playing && length(animations) > 0) {
    anim_time += dt * anim_speed
    duration = animations[current_anim].duration
    if (duration > 0) {
      while (anim_time > duration) {
        anim_time -= duration
      }
    }
  }
}

function _switch_to_style(new_style) {
  if (style == new_style) return
  style = new_style
  lance3d.switch_style(style)
  log.console("Switched to " + style + " style")
}

function _draw() {
  var pose = null

  // Clear with a nice color based on style
  if (style == "ps1") {
    lance3d.clear(0.1, 0.05, 0.15, 1.0)
  } else if (style == "n64") {
    lance3d.clear(0.0, 0.1, 0.2, 1.0)
  } else {
    lance3d.clear(0.05, 0.05, 0.1, 1.0)
  }
  
  // Set up camera
  lance3d.camera_perspective(60, 0.1, 100)
  
  // Calculate camera position from orbit
  var cam_x = math.sine(cam_yaw) * math.cosine(cam_pitch) * cam_distance
  var cam_y = math.sine(cam_pitch) * cam_distance + cam_target_y
  var cam_z = math.cosine(cam_yaw) * math.cosine(cam_pitch) * cam_distance
  
  lance3d.camera_look_at({x: cam_x, y: cam_y, z: cam_z}, {x: 0, y: cam_target_y, z: 0})
  
  // Draw the model
  if (model) {
    pose = null
    if (length(animations) > 0) {
      pose = lance3d.sample_pose(model, current_anim, anim_time)
    }
    lance3d.draw_model(model, null, pose)
  }
}

function frame() {
  // Begin frame
  lance3d._begin_frame()
  
  // Process events
  if (!lance3d._process_events()) {
    log.console("Exiting...")
    $stop()
    return
  }
  
  // Calculate delta time
  var now = time_mod.number()
  var dt = now - last_time
  last_time = now
  
  // Update
  _update(dt)
  
  // Draw
  _draw()
  
  // End frame
  lance3d._end_frame()
  
  // Schedule next frame
  $delay(frame, 1/240)
}

// Start
_init()