local loveCompress=love.data.compress

local int=math.floor
local char,byte=string.char,string.byte
local ins=table.insert

local BAG,FIELD,MISSION,CUSTOMENV,GAME=BAG,FIELD,MISSION,CUSTOMENV,GAME

local DATA={}
--Sep symbol: 33 (!)
--Safe char: 34~126
--[[
	Count: 34~96
	Block: 97~125
	Encode: A[B] sequence, A = block ID, B = repeat times, no B means do not repeat.
	Example: "abcdefg" is [SZJLTOI], "a^aDb)" is [Z*63,Z*37,S*10]
]]
function DATA.copySequence()
	local str=""

	local count=1
	for i=1,#BAG+1 do
		if BAG[i+1]~=BAG[i]or count==64 then
			str=str..char(96+BAG[i])
			if count>1 then
				str=str..char(32+count)
				count=1
			end
		else
			count=count+1
		end
	end

	return str
end
function DATA.pasteSequence(str)
	TABLE.cut(BAG)
	local b,reg
	for i=1,#str do
		b=byte(str,i)
		if not reg then
			if b>=97 and b<=125 then
				reg=b-96
			else
				return
			end
		else
			if b>=97 and b<=125 then
				ins(BAG,reg)
				reg=b-96
			elseif b>=34 and b<=96 then
				for _=1,b-32 do
					ins(BAG,reg)
				end
				reg=false
			end
		end
	end
	if reg then ins(BAG,reg)end
	return true
end

function DATA.newBoard(f)--Generate a new board
	if f then
		return TABLE.shift(f)
	else
		local F={}
		for i=1,20 do F[i]={0,0,0,0,0,0,0,0,0,0}end
		return F
	end
end
function DATA.copyBoard(page)--Copy the [page] board
	local F=FIELD[page or 1]
	local str=""
	local H=0

	for y=20,1,-1 do
		for x=1,10 do
			if F[y][x]~=0 then
				H=y
				goto BREAK_topFound
			end
		end
	end
	::BREAK_topFound::

	--Encode field
	for y=1,H do
		local S=""
		local L=F[y]
		for x=1,10 do
			S=S..char(L[x]+1)
		end
		str=str..S
	end
	return STRING.packBin(str)
end
function DATA.copyBoards()
	local out={}
	for i=1,#FIELD do
		out[i]=DATA.copyBoard(i)
	end
	return table.concat(out,"!")
end
function DATA.pasteBoard(str,page)--Paste [str] data to [page] board
	if not page then page=1 end
	if not FIELD[page]then FIELD[page]=DATA.newBoard()end
	local F=FIELD[page]

	--Decode
	str=STRING.unpackBin(str)
	if not str then return end

	local fX,fY=1,1--*ptr for Field(r*10+(c-1))
	local p=1
	while true do
		local b=byte(str,p)--1byte

		--Str end
		if not b then
			if fX~=1 then
				return
			else
				break
			end
		end

		local id=b%32-1--Block id
		if id>26 then return end--Illegal blockid
		b=int(b/32)--Mode id

		F[fY][fX]=id
		if fX<10 then
			fX=fX+1
		else
			fY=fY+1
			if fY>20 then break end
			fX=1
		end
		p=p+1
	end

	for y=fY,20 do
		for x=1,10 do
			F[y][x]=0
		end
	end

	return true
end

--[[
	Mission: 34~114
	Count: 115~126
	Encode: [A] or [AB] sequence, A = mission ID, B = repeat times, no B means do not repeat.

	_1=01,_2=02,_3=03,_4=04,
	A1=05,A2=06,A3=07,A4=08,
	PC=09,
	Z1=11,Z2=12,Z3=13,
	S1=21,S2=22,S3=23,
	J1=31,J2=32,J3=33,
	L1=41,L2=42,L3=43,
	T1=51,T2=52,T3=53,
	O1=61,O2=62,O3=63,O4=64,
	I1=71,I2=72,I3=73,I4=74,
]]
function DATA.copyMission()
	local _
	local str=""

	local count=1
	for i=1,#MISSION+1 do
		if MISSION[i+1]~=MISSION[i]or count==13 then
			_=33+MISSION[i]
			str=str..char(_)
			if count>1 then
				str=str..char(113+count)
				count=1
			end
		else
			count=count+1
		end
	end

	return str
end
function DATA.pasteMission(str)
	local b
	local mission={}
	local reg
	for i=1,#str do
		b=byte(str,i)
		if not reg then
			if b>=34 and b<=114 then
				reg=b-33
			else
				return
			end
		else
			if b>=34 and b<=114 then
				if missionEnum[reg]then
					ins(mission,reg)
					reg=b-33
				else
					return
				end
			elseif b>=115 and b<=126 then
				for _=1,b-113 do
					ins(mission,reg)
				end
				reg=false
			end
		end
	end
	if reg then
		ins(mission,reg)
	end

	MISSION=mission
	return true
end

function DATA.copyQuestArgs()
	local ENV=CUSTOMENV
	local str=""..
		ENV.holdCount..
		(ENV.ospin and"O"or"Z")..
		(ENV.missionKill and"M"or"Z")..
		ENV.sequence
	return str
end
do--function DATA.pasteQuestArgs(str)
	function DATA.pasteQuestArgs(str)
		if #str<4 then return end
		local ENV=CUSTOMENV
		ENV.holdCount=		str:byte(1)-48
		ENV.ospin=			str:byte(2)~=90
		ENV.missionKill=	str:byte(3)~=90
		ENV.sequence=		str:sub(4)
		return true
	end
end

--[[
	Table data format:
		{frame,event, frame,event, ...}

	Byte data format: (1 byte each period)
		dt, event, dt, event, ...
	all data range from 0 to 127
	large value will be encoded as 1xxxxxxx(high)-1xxxxxxx-...-0xxxxxxx(low)

	Example (decoded):
		6,1, 20,-1, 0,2, 26,-2, 872,4, ...
	This means:
		Press key1 at 6f
		Release key1 at 26f (6+20)
		Press key2 at the same time (26+0)
		Release key 2 after 26 frame (26+26)
		Press key 4 after 872 frame (52+872)
		...
]]
function DATA.dumpRecording(list,ptr)
	local out=""
	local buffer,buffer2=""
	if not ptr then ptr=1 end
	local prevFrm=list[ptr-2]or 0
	while list[ptr]do
		--Flush buffer
		if #buffer>10 then
			out=out..buffer
			buffer=""
		end

		--Encode time
		local t=list[ptr]-prevFrm
		prevFrm=list[ptr]
		if t>=128 then
			buffer2=char(t%128)
			t=int(t/128)
			while t>=128 do
				buffer2=char(128+t%128)..buffer2
				t=int(t/128)
			end
			buffer=buffer..char(128+t)..buffer2
		else
			buffer=buffer..char(t)
		end

		--Encode event
		t=list[ptr+1]
		if t>=128 then
			buffer2=char(t%128)
			t=int(t/128)
			while t>=128 do
				buffer2=char(128+t%128)..buffer2
				t=int(t/128)
			end
			buffer=buffer..char(128+t)..buffer2
		else
			buffer=buffer..char(t)
		end

		--Step
		ptr=ptr+2
	end
	return out..buffer,ptr
end
function DATA.pumpRecording(str,L)
	local len=#str
	local p=1

	local curFrm=L[#L-1]or 0
	local code
	while p<=len do
		--Read delta time
		code=0
		local b=byte(str,p)
		while b>=128 do
			code=code*128+b-128
			p=p+1
			b=byte(str,p)
		end
		curFrm=curFrm+code*128+b
		L[#L+1]=curFrm
		p=p+1

		local event=0
		b=byte(str,p)
		while b>=128 do
			event=event*128+b-128
			p=p+1
			b=byte(str,p)
		end
		L[#L+1]=event*128+b
		p=p+1
	end
end
do--function DATA.saveRecording()
	local noRecList={"custom","solo","round","techmino"}
	local function getModList()
		local res={}
		for _,v in next,GAME.mod do
			if v.sel>0 then
				ins(res,{v.no,v.sel})
			end
		end
		return res
	end
	function DATA.saveRecording()
		--Filtering modes that cannot be saved
		for _,v in next,noRecList do
			if GAME.curModeName:find(v)then
				LOG.print("Cannot save recording of this mode now!",'warn')
				return
			end
		end

		--Write file
		local fileName=os.date("replay/%Y_%m_%d_%a_%H%M%S.rep")
		if not love.filesystem.getInfo(fileName)then
			local fileHead=
				os.date("%Y/%m/%d %A %H:%M:%S\n")..
				GAME.curModeName.."\n"..
				VERSION.string.."\n"..
				"Local Player"
			local fileBody=
				GAME.seed.."\n"..
				JSON.encode(GAME.setting).."\n"..
				JSON.encode(getModList()).."\n"..
				DATA.dumpRecording(GAME.rep)

			love.filesystem.write(fileName,fileHead.."\n"..loveCompress('string','zlib',fileBody))
			ins(REPLAY,fileName)
			FILE.save(REPLAY,'conf/replay')
			return true
		else
			LOG.print("Save failed: File already exists",'error')
		end
	end
end

return DATA