2 files changed, 70 insertions, 0 deletions
diff --git a/autoload/space_vlaze/enemy.vim b/autoload/space_vlaze/enemy.vim
new file mode 100644
index 0000000..377c803
--- /dev/null
+++ b/autoload/space_vlaze/enemy.vim
@@ -0,0 +1,52 @@
+function! space_vlaze#enemy#EnemyCharacter()
+	return '♤'
+endfunction
+
+
+if !exists('s:MAX_ENEMIES_ON_BOARD')
+	let s:MAX_ENEMIES_ON_BOARD = 50
+endif
+
+if !exists('s:MIN_ENEMIES_ON_BOARD')
+	let s:MIN_ENEMIES_ON_BOARD = 50
+endif
+
+
+function! space_vlaze#enemy#AddEnemiesToBoard()
+	let ticks = space_vlaze#game#Ticks()
+	
+	" At a 50ms refresh rate 100 ticks == 5 seconds
+	if ticks % 100 ==# 1
+		let new_enemy_count = ticks / 20
+		
+		if new_enemy_count <# s:MIN_ENEMIES_ON_BOARD
+			let new_enemy_count = s:MIN_ENEMIES_ON_BOARD
+		endif
+		
+		if new_enemy_count ># s:MAX_ENEMIES_ON_BOARD
+			let new_enemy_count = s:MAX_ENEMIES_ON_BOARD
+		endif
+		
+		let i = 0
+		while i < new_enemy_count
+			call space_vlaze#enemy#DropEnemyAtRandomCoordinates()
+			
+			let i += 1
+		endwhile
+	endif
+endfunction
+
+
+function! space_vlaze#enemy#DropEnemyAtRandomCoordinates()
+	let player_y = space_vlaze#player#PlayerY()
+	let player_x = space_vlaze#player#PlayerX()
+	let y = player_y
+	let x = player_x
+	
+	while player_y ==# y && player_x ==# x
+		let y = space_vlaze#random#Random(space_vlaze#game#BoardHeight() - 1)
+		let x = space_vlaze#random#Random(space_vlaze#game#BoardWidth() - 1)
+	endwhile
+	
+	call space_vlaze#game#SetBoardCell(y, x, space_vlaze#enemy#EnemyCharacter())
+endfunction
diff --git a/autoload/space_vlaze/game.vim b/autoload/space_vlaze/game.vim
index a1e00b3..29ba52b 100644
--- a/autoload/space_vlaze/game.vim
+++ b/autoload/space_vlaze/game.vim
@@ -2,6 +2,7 @@ function! space_vlaze#game#Init()
 	let s:loop = 1
 	let s:score = 0
 	let s:start_time = localtime()
+	let s:ticks = 1
 	call space_vlaze#game#SetupWindow()
 	call space_vlaze#colors#Initialize()
 	call space_vlaze#game#InitializeBoard()
@@ -10,7 +11,9 @@ function! space_vlaze#game#Init()
 	while s:loop ==# 1
 		sleep 50ms
 		call space_vlaze#mappings#Listen()
+		call space_vlaze#enemy#AddEnemiesToBoard()
 		call space_vlaze#game#RenderBoard()
+		let s:ticks += 1
 	endwhile
 endfunction
 
@@ -94,6 +97,21 @@ function! space_vlaze#game#IsWithinBoard(y, x)
 endfunction
 
 
+function! space_vlaze#game#BoardHeight()
+	return s:BOARD_HEIGHT
+endfunction
+
+
+function! space_vlaze#game#BoardWidth()
+	return s:BOARD_WIDTH
+endfunction
+
+
+function! space_vlaze#game#Ticks()
+	return s:ticks
+endfunction
+
+
 function! space_vlaze#game#Quit()
 	let s:loop = -1
 endfunction