Midday Navigator

--------------------------------------------------
--  Midday Navigator. Браузер для сети OpenNet  --
--             Автор: Zer0Galaxy                --
--------------------------------------------------
gpu  = require("component").gpu
kbd  = require("component").keyboard
computer=require("computer")
fs   = require("filesystem")
text = require("text")
term = require("term")
wlen = require("unicode").wlen
event= require("event")
on = require("opennet")

local cursorX, cursorY = 1, 1
local ShiftX = 0
local ShiftY = 0
local Left,Top = 1, 3
local WinW, WinH = gpu.getResolution()
WinH=WinH-Top+1
local Caption="Midday Navigator 1.0"
local Site=""
local txColour = 0xFFFFFF
local bgColour = 0x000000
local tagColour = 0x0080FF
local History = {}
local object={}

function winhead()
  gpu.setForeground(0xFFFFFF)
  gpu.setBackground(0x0000FF)
  gpu.fill(1,1, WinW,1, " ")  gpu.set(2,1, Caption)
  gpu.setBackground(0x00FF00) gpu.set(WinW-8,1, " S ")
  gpu.setBackground(0x0080FF) gpu.set(WinW-5,1, " < ")
  gpu.setBackground(0xFF0000) gpu.set(WinW-2,1, " X ")
  gpu.setForeground(0x000000)
  gpu.setBackground(0xFFFFFF)
  gpu.fill(1,2, WinW,1, " ")
  gpu.set(2,2, Site)
  gpu.setForeground(txColour)
  gpu.setBackground(bgColour)
end

function winwrite(value)
  value = text.detab(tostring(value))
  if wlen(value) == 0 then
    return
  end
  local line, nl
  repeat
    if cursorY > WinH then return end
    line, value, nl = text.wrap(value, WinW - (cursorX - 2), WinW)
    if cursorY>=1 then gpu.set(cursorX+Left-1-ShiftX, cursorY+Top-1, line) end
    cursorX = cursorX + wlen(line)
    if nl or (cursorX > WinW) then
      cursorX = 1
      cursorY = cursorY + 1
    end
  until not value
end

function winclear()
  object={}
  gpu.fill(Left, Top, WinW, WinH, " ")
  cursorX, cursorY = 1, 1
end

tags={}
tags['html']=function(arg)
  if arg.caption then Caption=arg.caption winhead() end
  local param=tonumber(arg.color)
  if param then txColour = param gpu.setForeground(param) end
  param=tonumber(arg.bgcolor)
  if param then bgColour = param gpu.setBackground(param) winclear() end
end
tags['font']=function(arg)
  local param=tonumber(arg.color)
  if param then gpu.setForeground(param) end
  param=tonumber(arg.bgcolor)
  if param then gpu.setBackground(param) end
end
tags['/font']=function()
    gpu.setForeground( txColour )
    gpu.setBackground( bgColour )
end
tags['cr']=function()
--  if cursorX>1 then
    cursorY=cursorY+1
    cursorX=1
--  end
end
tags['---']=function()
  if cursorX>1 then cursorY=cursorY+1 cursorX=1 end
  winwrite(string.rep('─',WinW))
end
tags['===']=function()
  if cursorX>1 then cursorY=cursorY+1 cursorX=1 end
  winwrite(string.rep('═',WinW))
end

local function line_check(obj,x,y)
  if y>=obj.y1 and y<=obj.y2 then
    if (x>=obj.x1 or y>obj.y1) and (x<=obj.x2 or y<obj.y2) then return true end
  end
end
local function bar_check(obj,x,y)
  return y>=obj.y1 and y<=obj.y2 and x>=obj.x1 and x<=obj.x2
end
local function ref_work(obj) load(obj.ref) end
tags['a']=function(arg)
  if arg.ref then
    table.insert(object, {check=line_check,
    x1=cursorX+Left-1-ShiftX, y1=cursorY+Top-1,
    work=ref_work, ref = arg.ref,
    col=gpu.getForeground()})
  end
  local color=tonumber(arg.color) or tagColour
  gpu.setForeground(color)
end
tags['/a']=function()
  local ref=object[#object]
  if ref and not ref.x2 then
    gpu.setForeground(ref.col or txColour)
    ref.x2, ref.y2 = cursorX+Left-2-ShiftX, cursorY+Top-1
  end
end

function tagWork(tag)
  local name=tag:match('%S+')
  if tags[name] then
    local params={}
    for k,v in tag:gmatch('(%w+)=([^%s"]+)') do params[k]=v end
    for k,v in tag:gmatch('(%w+)="([^"]+)"') do params[k]=v end
    tags[name](params)
  else
    winwrite( '<'..tag..'>' )
  end
end

function winline(line)
  if line then
    cursorY=line.Y-ShiftY
    cursorX=line.X
    local sLine=line.text
    while string.len(sLine) > 0 do
      local p1,p2
      p1=sLine:find("<")
      if p1 then p2=sLine:find(">",p1) end
      if p2 then
        winwrite(sLine:sub(1,p1-1))
        tagWork(sLine:sub(p1+1,p2-1))
        sLine=sLine:sub(p2+1)
      else
        winwrite(sLine)
        sLine=""
      end
    end
    if cursorY <= WinH then return true end
  end
end

function htmltext()
  winclear()
  local line=1
  for i=#lines,1,-1 do
    if lines[i].Y<=ShiftY then line=i break end
  end
  while winline(lines[line]) do
    line=line+1
    if lines[line] then lines[line].Y=ShiftY+cursorY lines[line].X=cursorX end
  end
end
function codetext()
  winclear()
  for i=1,WinH do
    if lines[i+ShiftY] then gpu.set(1-ShiftX,i+Top-1,lines[i+ShiftY].text)
    else break end
  end
end
wintext=htmltext

function winshift(shX,shY)
  ShiftX=ShiftX+shX
  ShiftY=ShiftY+shY
  if ShiftX<0 then ShiftX=0 end
  if ShiftY<0 then ShiftY=0 end
  wintext()
end

function load(sPath)
  if sPath=='' or sPath==nil or sPath=="\n" then winhead() return end
  if sPath:sub(-1)=="\n" then sPath=sPath:sub(1,-2) end
  lines={}
  ShiftX=0
  ShiftY=0
  Caption="Midday Navigator 1.0"
  txColour = 0xFFFFFF
  bgColour = 0x000000
  if sPath:sub(1,1)=="." then
    while sPath:sub(1,1)=="." do
      Site=Site:match("(.+)/.*") or Site
      sPath=sPath:sub(2)
    end
    Site=Site..sPath
  else
    Site=sPath
  end
  local host,doc=Site:match('(.-)/(.*)')
  if not host then host=Site doc=nil end
  if host=="" then
    local file=io.open(Site,"r")
    if file then
      for line in file:lines() do
        lines[#lines+1]={X=1,Y=math.huge,text=line}
      end
      file:close()
    else
      lines[1]={X=5,Y=1,text="<html>Файл <font color=0xFF0000>"..Site.."</font> не найден"}
    end
  else
    local MyIP,err=on.getIP()
    if MyIP then
      on.send(host,"get",doc)
      local adr,com,text
      repeat
        adr,com,text=on.receive(3)
      until com=="get" or not com
      if com=="get" then
        text=tostring(text)
        local line=1
        while #text>0 do
          local p=text:find("\n")
          if p then
            lines[line],text={X=1,Y=math.huge,text=text:sub(1,p-1)}, text:sub(p+1)
          else
            lines[line],text={X=1,Y=math.huge,text=text}, ""
          end
          line=line+1
        end
      else
        if adr then
          lines[1]={X=1,Y=math.huge,text="Ответ от узла "..tostring(adr)}
          lines[2]={X=1,Y=math.huge,text=tostring(text)}
        else
          lines[1]={X=1,Y=math.huge,text="Таймаут ожидания"}
        end
      end
    else
      lines[1]={X=5,Y=1,text="<html>Ошибка подключения к сети OpenNet: <font color=0xFF0000>"..err.."</font>"}
    end
  end
  wintext=codetext
  if lines[1] then
    lines[1].Y=1
    if string.find(lines[1].text,"<%s*html.*>") then wintext=htmltext end
  end
  if History[#History]~=Site then table.insert( History, Site ) end
  winhead()
  wintext()
end

local work=true
function read()
  gpu.setForeground( 0x000000 )
  gpu.setBackground( 0xFFFFFF )
  term.setCursor( 1, 2 )
  term.clearLine()
  term.setCursor( 2, 2 )
  load(term.read(History,false))
end
function save()
  if kbd then
    gpu.setForeground( 0x000000 )
    gpu.setBackground( 0xFFFFFF )
    term.setCursor( 1, 2 ) term.clearLine()
    term.setCursor( 2, 2 )
    term.write("Safe as: ")
    computer.pushSignal("key_down",kbd.address,0,200)
    local Name=term.read({"/download/"..Site:match("[^/]*$")},false):sub(1,-2)
    if Name~="" then
      if not fs.exists("download") then fs.makeDirectory("download") end
      local file=io.open(Name,"w")
      if file then
        for i=1,#lines-1 do file:write(lines[i].text.."\n") end
        file:write(lines[#lines].text)
        file:close()
      else
        term.clearLine()
        term.setCursor( 2, 2 )
        term.write("File "..Name.." can't be saved")
        computer.beep()
        os.sleep(2)
      end
    end
    winhead()
  end
end
function back()
  if #History>1 then
    History[#History]=nil
    load(History[#History])
  end
end
function quit()
  gpu.setForeground( 0xFFFFFF )
  gpu.setBackground( 0x000000 )
  term.clear()
  work=false
end

do
  local param=...
  if param then load(param) else winhead() read() end
end
local Sh=false
while work do
  local ev, _, X, Y, S=event.pull()
  if ev=="scroll" and Y>=Top then
    if Sh then winshift(-5*S,0)
    else winshift(0,-3*S) end
  end
  if ev=="key_down" then
    if Y==208 then winshift(0,3) end
    if Y==200 then winshift(0,-3) end
    if Y==203 then winshift(-5,0) end
    if Y==205 then winshift(5,0) end
    if Y==29 then Sh=true end
    if Y==15 then read() end
    if Sh and Y==31 then save() end
    if Y==14 then back() end
    if Sh and Y==17 then quit() end
  end
  if ev=="key_up" and Y==29 then Sh=false end
  if ev=="touch" and S==0 then
    if Y==1 then
      if X>=WinW-8 and X<=WinW-6 then save() end
      if X>=WinW-5 and X<=WinW-3 then back() end
      if X>=WinW-2 then quit() end
    elseif Y==2 then read()
    else
      for i=1,#object do
        if object[i]:check(X,Y) then object[i]:work() break end
      end
    end
  end
end