local bump       = require 'bump'
local bump_debug = require 'bump_debug'
io.stdout:setvbuf("no")
local instructions = [[
  bump.lua simple demo

    arrows: move
    tab: toggle debug info
    delete: run garbage collector
]]

local cols_len = 0 -- how many collisions are happening

-- World creation
local world = bump.newWorld()


-- Message/debug functions
local function drawMessage()
  local msg = instructions:format(tostring(shouldDrawDebug))
  jin.graphics.setColor(255, 255, 255)
  -- jin.graphics.print(msg, 550, 10)
end

local function drawDebug()
  bump_debug.draw(world)

  local statistics = ("fps: %d, mem: %dKB, collisions: %d, items: %d"):format(love.timer.getFPS(), collectgarbage("count"), cols_len, world:countItems())
  jin.graphics.setColor(255, 255, 255)
  -- jin.graphics.printf(statistics, 0, 580, 790, 'right')
end

local consoleBuffer = {}
local consoleBufferSize = 15
for i=1,consoleBufferSize do consoleBuffer[i] = "" end
local function consolePrint(msg)
  table.remove(consoleBuffer,1)
  consoleBuffer[consoleBufferSize] = msg
end

local function drawConsole()
  local str = table.concat(consoleBuffer, "\n")
  for i=1,consoleBufferSize do
    jin.graphics.setColor(255,255,255, i*255/consoleBufferSize)
    -- love.graphics.printf(consoleBuffer[i], 10, 580-(consoleBufferSize - i)*12, 790, "left")
  end
end

-- helper function
local function drawBox(box, r,g,b)
  jin.graphics.setColor(r,g,b,70)
  jin.graphics.rect("fill", box.x, box.y, box.w, box.h)
  jin.graphics.setColor(r,g,b)
  jin.graphics.rect("line", box.x, box.y, box.w, box.h)
end



-- Player functions
local player = { x=50,y=50,w=20,h=20, speed = 80, onGround = false}
vx = 0
vy = 0
local function updatePlayer(dt)
  local speed = player.speed
  if jin.keyboard.isDown('Right') then
    vx = speed
  elseif jin.keyboard.isDown('Left') then
    vx = -speed
  end 
  if jin.keyboard.isDown('Down') then
    vy = vy 
  elseif jin.keyboard.isDown('Up') then
    vy = vy
  elseif jin.keyboard.isDown('Space') and player.onGround then 
    vy = vy - 12000 * dt  
    print("jump")
    print("on sky")
    player.onGround = false
  end
  if not player.onGround then 
    vy = vy + 200 * dt
  end 
  if vx ~= 0 or vy ~= 0 then
    local cols
    local py = player.y
    player.x, player.y, cols, cols_len = world:move(player, player.x + vx * dt, player.y + vy * dt)
    if py == player.y then 
      player.onGround = true
      vy = 0
      print("on ground")
    end
    for i=1, cols_len do
      local col = cols[i]
      consolePrint(("col.other = %s, col.type = %s, col.normal = %d,%d"):format(col.other, col.type, col.normal.x, col.normal.y))
    end
  end
  vx = 0
end

local function drawPlayer()
  drawBox(player, 0, 255, 0)
end

-- Block functions

local blocks = {}

local function addBlock(x,y,w,h)
  local block = {x=x,y=y,w=w,h=h}
  blocks[#blocks+1] = block
  world:add(block, x,y,w,h)
end

local function drawBlocks()
  for _,block in ipairs(blocks) do
    drawBox(block, 255,0,0)
  end
end

function jin.core.onEvent(e)
  if e.type == "quit" then 
    jin.core.stop()
  end
  if e.type == "keydown" then 
    if e.key == "Escape" then 
      jin.core.stop()
    end 
  end
end

-- Main LÖVE functions

function jin.core.onLoad()
  world:add(player, player.x, player.y, player.w, player.h)

  addBlock(0,       0,     800, 32)
  addBlock(0,      32,      32, 600-32*2)
  addBlock(800-32, 32,      32, 600-32*2)
  addBlock(0,      600-32, 800, 32)

  for i=1,30 do
    addBlock( math.random(100, 600),
              math.random(100, 400),
              math.random(10, 100),
              math.random(10, 100)
    )
  end
end

function jin.core.onUpdate(dt)
  cols_len = 0
  updatePlayer(dt)
end

function jin.core.onDraw()
  drawBlocks()
  drawPlayer()
  if shouldDrawDebug then
    drawDebug()
    drawConsole()
  end
  drawMessage()
end