-------------------------------------------------------------------------------
 -- Copyright (c) 2013, Esoteric Software
 -- All rights reserved.
 -- 
 -- Redistribution and use in source and binary forms, with or without
 -- modification, are permitted provided that the following conditions are met:
 -- 
 -- 1. Redistributions of source code must retain the above copyright notice, this
 --    list of conditions and the following disclaimer.
 -- 2. Redistributions in binary form must reproduce the above copyright notice,
 --    this list of conditions and the following disclaimer in the documentation
 --    and/or other materials provided with the distribution.
 -- 
 -- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 -- ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 -- WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 -- DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 -- ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 -- (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 -- LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 -- ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 -- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 -- SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 ------------------------------------------------------------------------------

local utils = require "spine.utils"
local Bone = require "spine.Bone"
local Slot = require "spine.Slot"
local AttachmentResolver = require "spine.AttachmentResolver"

local Skeleton = {}
function Skeleton.new (skeletonData, group)
	if not skeletonData then error("skeletonData cannot be nil", 2) end

	local self = group or display.newGroup()
	self.data = skeletonData
	self.bones = {}
	self.slots = {}
	self.drawOrder = {}
	self.images = {}

	function self:updateWorldTransform ()
		for i,bone in ipairs(self.bones) do
			bone:updateWorldTransform(self.flipX, self.flipY)
		end

		for i,slot in ipairs(self.drawOrder) do
			if slot.attachment then
				local image = self.images[slot.attachment]
				if not image then image = self.data.attachmentResolver:resolve(self, slot.attachment) end
				if image ~= AttachmentResolver.failed then
					image.x = slot.bone.worldX + slot.attachment.x * slot.bone.m00 + slot.attachment.y * slot.bone.m01
					image.y = -(slot.bone.worldY + slot.attachment.x * slot.bone.m10 + slot.attachment.y * slot.bone.m11)
					image.rotation = -(slot.bone.worldRotation + slot.attachment.rotation)
					image.xScale = slot.bone.worldScaleX + slot.attachment.scaleX - 1
					image.yScale = slot.bone.worldScaleY + slot.attachment.scaleY - 1
					if self.flipX then
						image.xScale = -image.xScale
						image.rotation = -image.rotation
					end
					if self.flipY then
						image.yScale = -image.yScale
						image.rotation = -image.rotation
					end
					image:setFillColor(slot.r, slot.g, slot.b, slot.a)
					self:insert(image)
				end
			end
		end

		if self.debug then
			for i,bone in ipairs(self.bones) do
				if not bone.line then bone.line = display.newLine(0, 0, bone.data.length, 0) end
				bone.line.x = bone.worldX
				bone.line.y = -bone.worldY
				bone.line.rotation = -bone.worldRotation
				if self.flipX then
					bone.line.xScale = -1
					bone.line.rotation = -bone.line.rotation
				else
					bone.line.xScale = 1
				end
				if self.flipY then
					bone.line.yScale = -1
					bone.line.rotation = -bone.line.rotation
				else
					bone.line.yScale = 1
				end
				bone.line:setColor(255, 0, 0)
				self:insert(bone.line)

				if not bone.circle then bone.circle = display.newCircle(0, 0, 3) end
				bone.circle.x = bone.worldX
				bone.circle.y = -bone.worldY
				bone.circle:setFillColor(0, 255, 0)
				self:insert(bone.circle)
			end
		end
	end

	function self:setToBindPose ()
		self:setBonesToBindPose()
		self:setSlotsToBindPose()
	end

	function self:setBonesToBindPose ()
		for i,bone in ipairs(self.bones) do
			bone:setToBindPose()
		end
	end

	function self:setSlotsToBindPose ()
		for i,slot in ipairs(self.slots) do
			slot:setToBindPose()
		end
	end

	function self:getRootBone ()
		return self.bones[1]
	end

	function self:findSlot (slotName)
		if not slotName then error("slotName cannot be nil.", 2) end
		for i,slot in ipairs(self.slots) do
			if slot.data.name == slotName then return slot end
		end
		return nil
	end

	function self:setSkin (skinName)
		local newSkin
		if skinName then
			newSkin = self.data:findSkin(skinName)
			if not newSkin then error("Skin not found: " .. skinName, 2) end
			if self.skin then
				-- Attach all attachments from the new skin if the corresponding attachment from the old skin is currently attached.
				for k,v in self.skin.attachments do
					local attachment = v[3]
					local slotIndex = v[1]
					local slot = self.slots[slotIndex]
					if slot.attachment == attachment then
						local name = v[2]
						local newAttachment = newSkin:getAttachment(slotIndex, name)
						if newAttachment then slot:setAttachment(newAttachment) end
					end
				end
			end
		end
		self.skin = newSkin
	end

	function self:getAttachment (slotName, attachmentName)
		if not slotName then error("slotName cannot be nil.", 2) end
		if not attachmentName then error("attachmentName cannot be nil.", 2) end
		local slotIndex = self.data:findSlotIndex(slotName)
		if slotIndex == -1 then error("Slot not found: " .. slotName, 2) end
		if self.skin then return self.skin:getAttachment(slotIndex, attachmentName) end
		if self.data.defaultSkin then
			local attachment = self.data.defaultSkin:getAttachment(slotIndex, attachmentName)
			if attachment then return attachment end
		end
		return nil
	end

	function self:setAttachment (slotName, attachmentName)
		if not slotName then error("slotName cannot be nil.", 2) end
		if not attachmentName then error("attachmentName cannot be nil.", 2) end
		for i,slot in ipairs(self.slots) do
			if slot.data.name == slotName then
				slot:setAttachment(self:getAttachment(slotName, attachmentName))
				return
			end
		end
		error("Slot not found: " + slotName, 2)
	end

	function self:update (delta)
		self.time = self.time + delta
	end

	for i,boneData in ipairs(skeletonData.bones) do
		local parent
		if boneData.parent then parent = self.bones[utils.indexOf(skeletonData.bones, boneData.parent)] end
		table.insert(self.bones, Bone.new(boneData, parent))
	end

	for i,slotData in ipairs(skeletonData.slots) do
		local bone = self.bones[utils.indexOf(skeletonData.bones, slotData.boneData)]
		local slot = Slot.new(slotData, self, bone)
		table.insert(self.slots, slot)
		table.insert(self.drawOrder, slot)
	end

	return self
end
return Skeleton