From ad639a9d7806022b6474f20c0f7fbe7f949009f6 Mon Sep 17 00:00:00 2001
From: Jason Woofenden <jason@jasonwoof.com>
Date: Sun, 14 Apr 2013 23:18:12 -0400
Subject: [PATCH] clean up and comment code in blip_selection

---
 main.coffee |   75 +++++++++++++++++++++++++++++++----------------------------
 1 file changed, 40 insertions(+), 35 deletions(-)

diff --git a/main.coffee b/main.coffee
index be5a85f..4aaf2d5 100644
--- a/main.coffee
+++ b/main.coffee
@@ -85,7 +85,6 @@ board_left_px = [] # array of pixel coordinates for left of column
 board_aboves = [] # array of tile numbers above, starting from top
 board_below = [] # tile number of next tile below or false
 
-slides = []
 selected = []
 
 letters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
@@ -234,9 +233,6 @@ init_board = ->
 		new_letter_queue = (encoded.substr 0, board_tiles).split ''
 		score = parseInt(encoded.substr(board_tiles), 10)
 
-	# how far each tile needs to be slid down
-	slides = (0 for i in board)
-
 	# work out which grid spaces are connected
 	# (neighbors, above, down)
 	init_board_layout()
@@ -285,9 +281,6 @@ selected_word = ->
 	word += board[i] for i in selected
 	return word.toLowerCase()
 
-html_slide = (num) ->
-	html_tiles[num].animate {top: "#{tile_top_px[num]}px"}, slide_ms
-
 save_game = ->
 	encoded = ''
 	for t in board
@@ -296,42 +289,54 @@ save_game = ->
 	set_cookie 'hexbog', encoded, 365
 	window.location.hash = encoded
 
+# remove the selected tiles from the board, create new tiles, and slide everything into place
 blip_selection = ->
-	faders = selected.clone().num_sort()
+	faders = selected.num_sort()
 	selected = []
-	for num in faders
-		html_tiles[num].unbind('click').fadeOut fade_ms
-	timeout fade_ms, ->
-		top_tile = -1
-		new_px = 0
-		new_slide = 0
-		for fader in faders
-			cur_top = board_aboves[fader][0]
-			if cur_top is undefined
-				cur_top = fader
-			if top_tile isnt cur_top
-				new_px = -20 - tile_width
-				new_slide = 1
-				top_tile = cur_top
-			html_tiles[fader].remove()
-			dest = fader
-			aboves = board_aboves[fader].clone().reverse()
+	update_selection_display()
+	for i in faders
+		html_tiles[i].unbind('click').fadeOut fade_ms
+	timeout fade_ms + 1, ->
+		# which tiles need to be slid down
+		sliders = (false for i in board)
+
+		prev_col_top = null
+		next_new_y = null
+		for deleted in faders
+			# find the tile number of the top tile in this column
+			if board_aboves[deleted].length is 0
+				col_top = deleted
+			else
+				col_top = board_aboves[deleted][0]
+
+			# reset location where new tiles appear when we change columns
+			if prev_col_top isnt col_top
+				next_new_y = -10 - tile_width
+				prev_col_top = col_top
+
+			html_tiles[deleted].remove()
+
+			# For each each tile above the one we've deleted:
+			# 1. move it down one slot in the data scructures
+			# 2. mark it as needing to slide
+			dest = deleted
+			aboves = board_aboves[deleted].clone().reverse()
 			for above in aboves
 				html_tiles[dest] = html_tiles[above]
 				html_tiles[dest].data 'tile_number', dest
 				board[dest] = board[above]
-				slides[dest] = slides[above] + 1
+				sliders[dest] = true
 				--dest
-			new_tile top_tile, board_left_px[top_tile], new_px
-			slides[top_tile] = new_slide
-			new_px -= tile_width
-			new_px -= 50
-			new_slide += 1
-		for i in [0 .. board.length - 1]
-			if slides[i]
-				html_slide i
+			sliders[col_top] = true # the new tile needs to be slid down too
+
+			new_tile col_top, board_left_px[col_top], next_new_y
+			next_new_y -= tile_width + 50
+
+		for slide, i in sliders
+			if slide
+				html_tiles[i].animate {top: "#{tile_top_px[i]}px"}, slide_ms
+				sliders[i] = false
 		save_game()
-	update_selection_display()
 
 activate_selection = ->
 	word = selected_word()
-- 
1.7.10.4