local core_cursor=require("core/cursor")
local unicode=require("unicode")
local kb=require("keyboard")
local tty=require("tty")

core_cursor.horizontal={}

function core_cursor.touch(cursor,gx,gy)
if cursor.len>0 then
local win=tty.window
gx,gy=gx-win.dx,gy-win.dy
while true do
local x,y,d=win.x,win.y,win.width
local dx=((gy*d+gx)-(y*d+x))
if dx==1 then
dx=unicode.wlen(unicode.sub(cursor.data,cursor.index+1,cursor.index+1))==2 and 0 or dx
end
if dx==0 then
break
end
cursor:move(dx>0 and 1 or-1)
if x==win.x and y==win.y then
break
end
end
end
end

function core_cursor.tab(cursor)
local hints=cursor.hint
if not hints then return end
if not cursor.cache then
cursor.cache=
type(hints)=="table"and hints or
hints(cursor.data,cursor.index+1)or
{}
cursor.cache.i=-1
end

local cache=cursor.cache

if#cache==1 and cache.i==0 then

cursor.cache=hints(cache[1],cursor.index+1)
if not cursor.cache then return end
cursor.cache.i=-1
cache=cursor.cache
end

local change=kb.isShiftDown()and-1 or 1
cache.i=(cache.i+change)%math.max(#cache,1)
local next=cache[cache.i+1]
if next then
local tail=unicode.len(cursor.data)-cursor.index
cursor:move(cursor.len)
cursor:update(-cursor.len)
cursor:update(next,-tail)
end
end

function core_cursor.horizontal:scroll(num,final_index)
self:move(self.vindex-self.index)

self.vindex=self.vindex+num
self.index=self.index+num

self:echo("\0277"..
unicode.sub(self.data,self.index+1)..
"\27[K\0278")

self:move(final_index-self.index)
end

function core_cursor.horizontal:echo(arg,num)
local w=tty.window
w.nowrap=self.nowrap
if arg==""then
local width=w.width
if w.x>=width then

width=width-math.max(unicode.wlen(unicode.sub(self.data,self.index+1,self.index+1))-1,0)
if w.x>width then
local s1=unicode.sub(self.data,self.vindex+1,self.index)
self:scroll(unicode.len(unicode.wtrunc(s1,w.x-width+1)),self.index)
end
end

elseif arg==kb.keys.left then
if self.index<self.vindex then
local s2=unicode.sub(self.data,self.index+1)
w.x=w.x-num+unicode.wlen(unicode.sub(s2,1,self.vindex-self.index))
local current_x=w.x
self:echo(s2)
w.x=current_x
self.vindex=self.index
return true
end
elseif arg==kb.keys.right then
w.x=w.x+num
return self:echo("")
end
return core_cursor.vertical.echo(self,arg,num)
end

function core_cursor.horizontal:update(arg,back)
if back then


self:update(arg,false)
local x=tty.window.x
self:echo(arg)
tty.window.x=x
self:move(self.len-self.index+back)
return true
elseif not arg then
self.nowrap=true
self.clear="\27[K"
self.vindex=0
end
return core_cursor.vertical.update(self,arg,back)
end

setmetatable(core_cursor.horizontal,{__index=core_cursor.vertical})