local class = require('class')
local UI = require('ui')
local Event = require('event')
local Peripheral = require('peripheral')

--[[-- Glasses device --]]--
local Glasses = class()
function Glasses:init(args)

  local defaults = {
    backgroundColor = colors.black,
    textColor = colors.white,
    textScale = .5,
    backgroundOpacity = .5,
    multiplier = 2.6665,
--    multiplier = 2.333,
  }
  defaults.width, defaults.height = term.getSize()

  UI.setProperties(defaults, args)
  UI.setProperties(self, defaults)

  self.bridge = Peripheral.get({
    type = 'openperipheral_bridge',
    method = 'addBox',
  })
  self.bridge.clear()

  self.setBackgroundColor = function(...) end
  self.setTextColor = function(...) end

  self.t = { }
  for i = 1, self.height do
    self.t[i] = {
      text = string.rep(' ', self.width+1),
      --text = self.bridge.addText(0, 40+i*4, string.rep(' ', self.width+1), 0xffffff),
      bg = { },
      textFields = { },
    }
  end
end

function Glasses:setBackgroundBox(boxes, ax, bx, y, bgColor)
  local colors = {
    [ colors.black ] = 0x000000,
    [ colors.brown ] = 0x7F664C,
    [ colors.blue  ] = 0x253192,
    [ colors.red   ] = 0xFF0000,
    [ colors.gray  ] = 0x272727,
    [ colors.lime  ] = 0x426A0D,
    [ colors.green ] = 0x2D5628,
    [ colors.white ] = 0xFFFFFF
  }

  local function overlap(box, ax, bx)
    if bx < box.ax or ax > box.bx then
      return false
    end
    return true
  end

  for _,box in pairs(boxes) do
    if overlap(box, ax, bx) then 
      if box.bgColor == bgColor then
        ax = math.min(ax, box.ax)
        bx = math.max(bx, box.bx)
        box.ax = box.bx + 1
      elseif ax == box.ax then
        box.ax = bx + 1
      elseif ax > box.ax then
        if bx < box.bx then
          table.insert(boxes, { -- split
            ax = bx + 1,
            bx = box.bx,
            bgColor = box.bgColor
          })
          box.bx = ax - 1
          break
        else
          box.ax = box.bx + 1
        end
      elseif ax < box.ax then
        if bx > box.bx then
          box.ax = box.bx + 1 -- delete
        else
          box.ax = bx + 1
        end
      end
    end
  end
  if bgColor ~= colors.black then
    table.insert(boxes, {
      ax = ax,
      bx = bx,
      bgColor = bgColor
    })
  end

  local deleted
  repeat
    deleted = false
    for k,box in pairs(boxes) do
      if box.ax > box.bx then
        if box.box then
          box.box.delete()
        end
        table.remove(boxes, k)
        deleted = true
        break
      end
      if not box.box then
        box.box = self.bridge.addBox(
          math.floor(self.x + (box.ax - 1) * self.multiplier),
          self.y + y * 4,
          math.ceil((box.bx - box.ax + 1) * self.multiplier),
          4,
          colors[bgColor],
          self.backgroundOpacity)
      else
        box.box.setX(self.x + math.floor((box.ax - 1) * self.multiplier))
        box.box.setWidth(math.ceil((box.bx - box.ax + 1) * self.multiplier))
      end
    end
  until not deleted
end

function Glasses:write(x, y, text, bg)

  if x < 1 then
    error(' less ', 6)
  end
  if y <= #self.t then
    local line = self.t[y]
    local str = line.text
    str = str:sub(1, x-1) .. text .. str:sub(x + #text)
    self.t[y].text = str

    for _,tf in pairs(line.textFields) do
      tf.delete()
    end
    line.textFields = { }

    local function split(st)
      local words = { }
      local offset = 0
      while true do
        local b,e,w = st:find('(%S+)')
        if not b then
          break
        end
        table.insert(words, {
          offset = b + offset - 1,
          text = w,
        })
        offset = offset + e
        st = st:sub(e + 1)
      end
      return words
    end

    local words = split(str)
    for _,word in pairs(words) do
      local tf = self.bridge.addText(self.x + word.offset * self.multiplier,
                                     self.y+y*4, '', 0xffffff)
      tf.setScale(self.textScale)
      tf.setZ(1)
      tf.setText(word.text)
      table.insert(line.textFields, tf)
    end

    self:setBackgroundBox(line.bg, x, x + #text - 1, y, bg)
  end
end

function Glasses:clear(bg)
  for _,line in pairs(self.t) do
    for _,tf in pairs(line.textFields) do
      tf.delete()
    end
    line.textFields = { }
    line.text = string.rep(' ', self.width+1)
--    self.t[i].text.setText('')
  end
end

function Glasses:reset()
  self:clear()
  self.bridge.clear()
  self.bridge.sync()
end

function Glasses:sync()
  self.bridge.sync()
end

return Glasses