1 files changed, 72 insertions, 0 deletions
diff --git a/src/Step.elm b/src/Step.elm
new file mode 100644
index 0000000..7894e45
--- /dev/null
+++ b/src/Step.elm
@@ -0,0 +1,72 @@
+module Step where
+
+import Vec2 (..)
+import Game (..)
+import Player (..)
+import EnemyState (..)
+import Player (playerSpeed)
+import Enemy (enemySpeed, enemyMove, enemyAwayDist)
+import Input (Input)
+import Physics (getNewPosAndSpeed, getMove)
+import Board (boardSize, boardDiagonal)
+import Geometry (..)
+import RandomValues (RandomValues)
+
+step : Input -> Game -> Game
+step {dir, delta, randomValues} {time, player, enemyState, bestTime} =
+  if(playerEnemiesCollision time player enemyState.enemies) then
+    let newBestTime = if(time > bestTime) then time else bestTime
+    in  initialGame player.pos newBestTime
+  else
+    let newTime = time + delta
+        newPlayer = playerStep delta dir player
+        newEnemyState = enemyStep time randomValues enemyState
+    in  { time = newTime
+        , player = newPlayer
+        , enemyState = newEnemyState
+        , bestTime = bestTime
+        }
+
+playerStep : Float -> Vec2 -> Player -> Player
+playerStep dt dir player =
+  let (pos, speed) = getNewPosAndSpeed dt dir playerSpeed (player.pos, player.speed)
+  in  { pos = inBoard playerSize pos
+      , speed = speed
+      }
+
+enemyStep : Float -> RandomValues -> EnemyState -> EnemyState
+enemyStep time randomValues {enemies, spawn, lastSpawn} =
+  let isPresent enemy = (distance (enemyMove enemy time) originVec) < enemyAwayDist
+      presentEnemies = filter isPresent enemies
+  in  if time > lastSpawn + spawn then
+        let newEnemy =
+          { initTime = time
+          , initPos = enemyInitPos randomValues
+          , initDest = enemyDestination randomValues
+          , move initTime initPos initDest time =
+              let delta = time - initTime
+                  move = getMove (enemySpeed delta) (initDest `sub` initPos)
+              in  initPos `add` move
+          }
+        in { enemies = newEnemy :: presentEnemies
+           , spawn = spawn - sqrt(spawn) / 50
+           , lastSpawn = time
+           }
+      else { enemies = presentEnemies
+           , spawn = spawn
+           , lastSpawn = lastSpawn
+           }
+
+enemyInitPos : RandomValues -> Vec2
+enemyInitPos randomValues =
+  let angle = randomValues.enemyAngle * (degrees 360)
+      dist = boardDiagonal * 3 / 5
+  in  polarToCartesian angle dist
+
+enemyDestination : RandomValues -> Vec2
+enemyDestination randomValues =
+  let destWidth = boardSize.x
+      destHeight = boardSize.y
+  in  { x = destWidth * randomValues.enemyX - destWidth / 2
+      , y = destHeight * randomValues.enemyY - destHeight / 2
+      }