function love.load()

  math.randomseed(os.time())

  load_sounds()

  load_sprites()

  load_font()

  load_data()

  player = newAnimation(love.graphics.newImage("assets/img/animation/player-test-size.png"),20,30,1)
  fog = newAnimation(love.graphics.newImage("assets/img/fog/fog-sheet-resize.png"),20,30,1)
  chaser = newAnimation(love.graphics.newImage("assets/img/chaser/dr2.png"),26,33,1)

  block_width = sprite[1]:getWidth()
  block_height = sprite[1]:getHeight()
  block_depth = block_height / 2

  create_grid()

  grid_x = love.graphics.getWidth()/2
  grid_y = love.graphics.getHeight()/2

  create_player()
  create_portal()
  create_chaser()

  choose_drone()
  change_title()

end

function love.update(dt)

  move_chaser()

  local terrain = get_terrain(p_x,p_y)

  --play drone corresponding to current space if not playing
  if p_x == chaser_x and p_y == chaser_y then
    stop_old_drone(current_drone)

    change_title()

  elseif terrain<5 and sound_switched == false then
    stop_old_drone(current_drone)
    choose_drone()
    sound_switched = true
  elseif terrain>=5 then
    sound_switched = false
  end
  play_drone(current_drone)

  --player animation
  player.currentTime = player.currentTime + dt
  if player.currentTime >= player.duration then
    player.currentTime = player.currentTime - player.duration
  end

  --fog animation
  fog.currentTime = fog.currentTime + dt
  if fog.currentTime >= fog.duration then
    fog.currentTime = fog.currentTime - fog.duration
  end

  --chaser animation
  chaser.currentTime = chaser.currentTime + dt
  if chaser.currentTime >= chaser.duration then
    chaser.currentTime = chaser.currentTime - chaser.duration
  end

end

function love.keypressed(key)

  if key == 'down' then
    p_x = p_x + 1
  end
  if key == 'up' then
    p_x = p_x - 1
  end
  if key == 'left' then
    p_y = p_y - 1
  end
  if key == 'right' then
    p_y = p_y + 1
  end
  --keep the player on the board!
  if p_x<1 then p_x = 1 end
  if p_y<1 then p_y = 1 end
  if p_x>10 then p_x = 10 end
  if p_y>10 then p_y = 10 end

  --print('player x: '..p_x..' y: '..p_y)
  --print('grid piece there: '..grid[p_x][p_y])

  check_player_on_portal()

end

function love.draw()
  draw_grid()
  draw_player()
  draw_portal()

  draw_text()

end

function load_sounds()
  local dir = 'assets/audio/drones-pack/'
  local files = love.filesystem.getDirectoryItems(dir)
  drone = {}
    for k, file in ipairs(files) do
	 --print(k .. ". " .. file) --list all soundfiles as loading
	 drone[k] = love.audio.newSource(dir..file, "stream")
    end

end

function create_grid()
  grid_size = 10
  grid = {}
  for x = 1,grid_size do
     grid[x] = {}
     for y = 1,grid_size do
	--make space a random tile
	grid[x][y] = love.math.random(#sprite)
     end
  end

end

function create_player()
  p_x = 1
  p_y = 1
end

function create_portal()
  portal_x = love. math.random(10)
  portal_y = love.math.random(10)
  --print('portal created at '..portal_x,portal_y)

  building_base = love.math.random(#building_sprite-6)
end

function create_chaser()
  chaser_x= love. math.random(10)
  chaser_y = love.math.random(10)
  --print('chaser created '..chaser_x..','..chaser_y)
end


function draw_grid()
  for x = 1,grid_size do
     for y = 1,grid_size do

       love.graphics.draw(sprite[grid[x][y]],
	      grid_x + ((y-x) * (block_width / 2)),
	      grid_y + ((x+y) * (block_depth / 2)) - (block_depth * (grid_size / 2)) - block_depth)

       --draw fog on terrain<3
       if grid[x][y]<3 then
         draw_fog(x,y)
       end

       --draw portal
       if x == portal_x and y == portal_y then
       love.graphics.draw(building_sprite[3],
	      grid_x + ((y-x) * (block_width / 2)),
	      grid_y + ((x+y) * (block_depth / 2)) - (block_depth * (grid_size / 2)) - block_depth)

        end

	--draw chaser
	if x == chaser_x and y == chaser_y then
          draw_chaser(x,y)
	end


     end

  end

end

function draw_player()
  local spriteNum = math.floor(player.currentTime / player.duration * #player.quads) + 1

  love.graphics.draw(player.spriteSheet, player.quads[spriteNum], grid_x + ((p_y-p_x) * (block_width / 2)) + block_width/4, grid_y + ((p_x+p_y) * (block_depth / 2)) - (block_depth * (grid_size / 2)) - block_depth - block_height/8, 0, 2)

end

function draw_fog(fog_x,fog_y)
  --draw all fog at simultaneous stage of animation
  --local spriteNum = math.floor(fog.currentTime / fog.duration * #fog.quads) + 1

  -- or: each fog animation sprite starts at different stage
  local spriteNum = math.floor(fog.currentTime / fog.duration * grid[fog_x][fog_y]) + 1

  love.graphics.draw(fog.spriteSheet, fog.quads[spriteNum], grid_x + ((fog_y-fog_x) * (block_width / 2)) + block_width/4, grid_y + ((fog_x+fog_y) * (block_depth / 2)) - (block_depth * (grid_size / 2)) - block_depth - block_height/8, 0, 2)

end

function draw_chaser(chaser_x,chaser_y)
  local spriteNum = math.floor(chaser.currentTime / chaser.duration * #chaser.quads) + 1

  love.graphics.draw(chaser.spriteSheet, chaser.quads[spriteNum], grid_x + ((chaser_x-chaser_y) * (block_width / 2)) + block_width/4, grid_y + ((chaser_x+chaser_y) * (block_depth / 2)) - (block_depth * (grid_size / 2)) - block_depth - block_height/8, 0, 2)

end

function draw_portal()
  local spriteNum = math.floor(player.currentTime / player.duration * 2) + building_base

  love.graphics.draw(building_sprite[spriteNum], grid_x + ((portal_y-portal_x) * (block_width / 2)) + block_width/4, grid_y + ((portal_x+portal_y) * (block_depth / 2)) - (block_depth * (grid_size / 2)) - block_depth - block_height/4, 0, 1)

end

function move_chaser()
  if chaser_x<1 then chaser_x = 1 end
  if chaser_y<1 then chaser_y = 1 end
  if chaser_x>10 then chaser_x = 10 end
  if chaser_y>10 then chaser_y = 10 end
  if love.math.random(100)<3 then
    chaser_x = chaser_x + love.math.random(-1,1)
    chaser_y = chaser_y + love.math.random(-1,1)
  end
  --print('chaser_x '..chaser_x..' chaser_y '..chaser_y)
end

function newAnimation(image, width, height, duration)
    local player = {}
    player.spriteSheet = image;
    player.quads = {};

    for y = 0, image:getHeight() - height, height do
        for x = 0, image:getWidth() - width, width do
            table.insert(player.quads, love.graphics.newQuad(x, y, width, height, image:getDimensions()))
        end
    end

    player.duration = duration or 1
    player.currentTime = 0

    return player
end

function get_terrain(x,y)
  return grid[p_x][p_y]
end

function play_drone(terrain)
  if not drone[terrain]:isPlaying() then

    love.audio.setEffect('dronezone', {type = 'reverb'})
    love.audio.setEffect('cave', {type = 'echo'})

    drone[terrain]:setEffect('cave')
    drone[terrain]:setEffect('ensemble')

    love.audio.play(drone[terrain])
  end
end

function load_sprites()

  local dir = 'assets/img/ground/'
  local files = love.filesystem.getDirectoryItems(dir)
  sprite = {}

  --load terrain
    for k, file in ipairs(files) do
	 --print(k .. ". " .. file) --list all sprites as loading
	 sprite[k] = love.graphics.newImage(dir..file)
    end

  --sprinkle some plants in

  local dir = 'assets/img/plants/'
  local files = love.filesystem.getDirectoryItems(dir)
  for i=1,5 do
    sprite[love.math.random(#sprite)] = love.graphics.newImage(dir..files[love.math.random(#files)])
  end

  --sprinkle some special objects in
  local dir = 'assets/img/objects/'
  local files = love.filesystem.getDirectoryItems(dir)

  --cycle through all tiles, replace all low number ones <5
  for j=1,10 do
    sprite[j] = love.graphics.newImage(dir..files[love.math.random(#files)])
   end

   --local portal sprites saved as building_sprites table
  building_sprite = {}
  local dir = 'assets/img/buildings/'
  local files = love.filesystem.getDirectoryItems(dir)
  for l=1,#files do
    building_sprite[l] = love.graphics.newImage(dir..files[l])
  end

end

function choose_drone()
  current_drone = love.math.random(#drone)
end

function stop_old_drone(old_drone)
    love.audio.stop(drone[old_drone])
end

function check_player_on_portal()
  if p_x == portal_x and p_y == portal_y then
    create_grid()
    choose_drone()
    create_portal()
    change_title()
  end
end

function load_data()
  environment = {}
  for line in love.filesystem.lines("assets/data/environments.txt") do
    table.insert(environment, line)
  end

  sense = {}
  for line in love.filesystem.lines("assets/data/senses.txt") do
    table.insert(sense, line)
  end

  transition = {}
  for line in love.filesystem.lines("assets/data/transition.txt") do
    table.insert(transition, line)
  end

end

function draw_text()
  love.graphics.print(title, 100, 100)
end

function change_title()
  current_env = environment[love.math.random(#environment)]
  current_sense = sense[love.math.random(#sense)]
  current_transition = transition[love.math.random(#transition)]

  if love.math.random(2)>1 then
    title=current_transition..' '..current_env
  else 
    title=current_sense..' of '..current_env
  end

end

function load_font()
  font = love.graphics.newFont(18)
  love.graphics.setFont(font)

end