guiapi

gui = {}

function gui.w(obj)
    return obj.a - obj.x + 1
end
function gui.h(obj)
    return obj.b - obj.y + 1
end

local function twrite(str) -- From the Googol API
    local tbl = {}
    for char in string.gmatch(str, ".") do
        table.insert(tbl, char)
    end

    local skip = false
    for i=1, #tbl do
        if tbl[i] == "&" then
            if string.match(tbl[i+1], "%x") then
                skip = true
                term.setTextColor(2^tonumber(tbl[i+1], 16))
            else
                write("&")
            end

        elseif tbl[i] == "#" then
            if string.match(tbl[i+1], "%x") then
                skip = true
                term.setBackgroundColor(2^tonumber(tbl[i+1], 16))
            else
                write("#")
            end

        elseif not skip then
            write(tbl[i])
        else
            skip = false
        end
    end
    --term.setTextColor(colors.white)
end

local function tlen(str)
    local len = 0
    local tbl = {}
    for char in string.gmatch(str, ".") do
        table.insert(tbl, char)
    end

    local skip = false
    for i=1, #tbl do
        if tbl[i] == "&" then
            if string.match(tbl[i+1], "%x") then
                skip = true
            else
                len = len + 1
            end

        elseif tbl[i] == "#" then
            if string.match(tbl[i+1], "%x") then
                skip = true
            else
                len = len + 1
            end

        elseif not skip then
            len = len + 1
        else
            skip = false
        end
    end
    return len
end

local function wordwrap(text, w)
    local lines = {} -- stores all the lines
    for match in string.gmatch(text, "[^\n]+") do -- seperate the block of text into seperate lines
        local len = 0
        local line = ""
        for word in string.gmatch(match, "[^%s]+") do -- word wrap if the line is too long
            word = word .. " "
            if tlen(line..word) > w then
                table.insert(lines, line)
                line = ""
            end
            line = line .. word
            while tlen(line) > w do
                table.insert(lines, line:sub(1, w))
                line = line:sub(w+1)
            end
        end
        table.insert(lines, line)
    end
    local delete = {}
    for i,v in pairs(lines) do
        lines[i] = v:match("^%s*(.-)%s*$")
        if lines[i] == "" then
            table.insert(delete, i)
        end
    end
    for i,v in pairs(delete) do lines[v] = nil end
    return lines
end

function gui.loadRaw(data)
    local guiobj = {}

    guiobj.data = data
    guiobj.menu = "default"

    function guiobj:getObject(i)
        if type(i) == "number" then
            return self.data[self.menu][i], i
        elseif type(i) == "string" then
            for i2,v2 in pairs(self.data[self.menu]) do
                if v.n == name then
                    return v2, i2
                end
            end
        end
    end

    function guiobj:setMenu(m)
        self.menu = m
    end

    function guiobj:connect(i, func)
        local obj = guiobj:getObject(i)
        if obj then
            obj.onClick = func
        else
            error("No object index "..i, 2)
        end
    end

    function guiobj:draw()
        term.setBackgroundColor(colors.black)
        term.clear()
        for i,v in pairs(self.data[self.menu]) do
            if not v.nfp then
                term.setBackgroundColor(v.bc)
                term.setTextColor(v.tc)
                for y = v.y, v.b do
                    term.setCursorPos(v.x, y)
                    term.write(string.rep(" ", gui.w(v)))
                end
                if v.t then
                    v.t = v.t:match("^%s*(.+)%s*$") or v.t
                    local lines = wordwrap(v.t, gui.w(v) - 2)
                    for i2,line in pairs(lines) do
                        term.setCursorPos(v.x + math.floor(gui.w(v)/2-tlen(line)/2), v.y + gui.h(v)/2 - #lines/2 + i2 - 1) -- ((h(v)%2==1 and h(v)/2) or ((h(v)/2)-1))
                        twrite(line)
                    end
                end
            else
                paintutils.drawImage(v.d, v.x, v.y)
            end
        end
    end

    function guiobj:process_event(event)
        if event[1] == "mouse_click" then
            for i = #self.data[self.menu], 1, -1 do
                local obj = self:getObject(i)
                if event[3] >= obj.x and event[3] <= obj.a and event[4] >= obj.y and event[4] <= obj.b then
                    if obj.onClick then obj:onClick() end
                    os.queueEvent("gui_click", event[2], i, obj.n, event[3] - obj.x + 1, event[4] - obj.y + 1)
                    break
                end
            end
        end
    end

    function guiobj:update(event)
        self:process_event(event)
        self:draw()
    end

    function guiobj:pairs()
        return pairs(self.data[self.menu])
    end

    return guiobj
end

function gui.load(path)
    local file = io.open(path, "r")
    local data = textutils.unserialize(file:read("*a"))
    file:close()

    return gui.loadRaw(data)
end

-- Misc. Useful Funcitons --

function gui.read( _sReplaceChar, _tHistory, wid, starttext)
    term.setCursorBlink( true )

    local sLine = starttext or ""
    local nHistoryPos = nil
    local nPos = (starttext and starttext:len()) or 0
    if _sReplaceChar then
        _sReplaceChar = string.sub( _sReplaceChar, 1, 1 )
    end

    local w, h = term.getSize()
    local sx, sy = term.getCursorPos()

    w = sx + wid - 1

    local function redraw( _sCustomReplaceChar )
        local nScroll = 0
        if sx + nPos >= w then
            nScroll = (sx + nPos) - w
        end

        term.setCursorPos( sx, sy )
        local sReplace = _sCustomReplaceChar or _sReplaceChar
        if sReplace then
            term.write( string.rep(sReplace, string.len(sLine) - nScroll) )
        else
            term.write( string.sub( sLine, nScroll + 1 ) )
        end
        term.setCursorPos( sx + nPos - nScroll, sy )
    end

    redraw()
    while true do
        local sEvent, param = os.pullEvent()
        if sEvent == "char" then
            sLine = string.sub( sLine, 1, nPos ) .. param .. string.sub( sLine, nPos + 1 )
            nPos = nPos + 1
            redraw()

        elseif sEvent == "key" then
            if param == keys.enter then
                -- Enter
                break

            elseif param == keys.left then
                -- Left
                if nPos > 0 then
                    nPos = nPos - 1
                    redraw()
                end

            elseif param == keys.right then
                -- Right
                if nPos < string.len(sLine) then
                    nPos = nPos + 1
                    redraw()
                end

            elseif param == keys.up or param == keys.down then
                -- Up or down
                if _tHistory then
                    redraw(" ");
                    if param == keys.up then
                        -- Up
                        if nHistoryPos == nil then
                            if #_tHistory > 0 then
                                nHistoryPos = #_tHistory
                            end
                        elseif nHistoryPos > 1 then
                            nHistoryPos = nHistoryPos - 1
                        end
                    else
                        -- Down
                        if nHistoryPos == #_tHistory then
                            nHistoryPos = nil
                        elseif nHistoryPos ~= nil then
                            nHistoryPos = nHistoryPos + 1
                        end
                    end

                    if nHistoryPos then
                        sLine = _tHistory[nHistoryPos]
                        nPos = string.len( sLine )
                    else
                        sLine = ""
                        nPos = 0
                    end
                    redraw()
                end
            elseif param == keys.backspace then
                -- Backspace
                if nPos > 0 then
                    redraw(" ");
                    sLine = string.sub( sLine, 1, nPos - 1 ) .. string.sub( sLine, nPos + 1 )
                    nPos = nPos - 1
                    redraw()
                end
            elseif param == keys.home then
                -- Home
                nPos = 0
                redraw()
            elseif param == keys.delete then
                if nPos < string.len(sLine) then
                    redraw(" ");
                    sLine = string.sub( sLine, 1, nPos ) .. string.sub( sLine, nPos + 2 )
                    redraw()
                end
            elseif param == keys["end"] then
                -- End
                nPos = string.len(sLine)
                redraw()
            elseif param == keys.tab then
                term.setCursorBlink(false)
                return sLine, true
            end
        end
    end

    term.setCursorBlink( false )
    term.setCursorPos( w + 1, sy )
    print()

    return sLine
end

function gui.textbox(prompt, starttext)
    term.setBackgroundColor(colors.black)
    term.clear()
    drawGui()

    local wid = ((prompt:len() <= 15 and 20) or prompt:len() + 5)
    local startx = tw/2 - wid/2
    local starty = ((th%2==1 and th/2) or ((th/2)-1)) - 2 -- 4/2

    term.setBackgroundColor(colors.lightGray)
    for i = 0, 3 do
        term.setCursorPos(startx, starty + i)
        print(string.rep(" ", wid))
    end

    term.setCursorPos(startx + 1, starty + 1)
    term.setTextColor(colors.black)
    print(prompt)

    term.setBackgroundColor(colors.gray)
    term.setCursorPos(startx + 1, starty + 2)
    print(string.rep(" ", wid-2))

    term.setCursorPos(startx + 1, starty + 2)
    term.setTextColor(colors.white)
    return gui.read(nil, nil, wid-2, starttext)
end

function gui.text(...)
    term.setBackgroundColor(colors.black)
    term.clear()
    drawGui()

    local wid = 0
    local strs = {...}
    for i,v in pairs(strs) do
        local _wid = ((v:len() <= 15 and 20) or v:len() + 5)
        wid = (_wid > wid and _wid) or wid
    end
    local startx = tw/2 - wid/2
    local starty = ((th%2==1 and th/2) or ((th/2)-1)) - 1 -- ~ 3/2

    term.setBackgroundColor(colors.lightGray)
    for i = 0, #strs + 1 do
        term.setCursorPos(startx, starty + i)
        print(string.rep(" ", wid))
    end

    for i,v in pairs(strs) do
        term.setCursorPos(startx + 1, starty + i)
        term.setTextColor(colors.gray)
        print(v)
    end

    os.pullEvent()
    return true
end

return gui