[WIP]windowManager

--install blittle
if not fs.exists( "stitch" ) then
    local h = http.get( 'https://pastebin.com/raw/CTrVdFK9' )
    if not h then
        error( "Failure to install stitch from 'CTrVdFK9'", 0 )
    end
    local data = h.readAll()
    h.close()
    local file = fs.open( "stitch", "w" )
    file.write( data )
    file.close()
end
--install statemachine
if not fs.exists( "statemachine" ) then
    local h = http.get( "https://pastebin.com/raw/3qe1iUQc" )
    if not h then
        error( "Failure to install state machine from '3qe1iUQc'", 0 )
    end
    local data = h.readAll()
    h.close()
    local file = fs.open( "statemachine", "w" )
    file.write( data )
    file.close()
end

--load statemachine
if not statemachine then
    os.loadAPI( "statemachine" )
end

--menu stuff
function menu( title, ... )
    --edit the background color to make the GUI more unique
        term.setBackgroundColor( colors.black )
        local debug = false --#turn to true to see what it's thinking
        local tArgs = { ... }
        local pages = {[1]={}}
        for i = 1, #tArgs, 1 do
                if #pages[ #pages ] == 7 then
                        pages[ #pages + 1 ] = {}
                end
                pages[ #pages ][ #pages[#pages] + 1 ] = tArgs[ i ]
        end
        local maxLen = 0
        for k, v in ipairs( tArgs ) do
                if #v > maxLen then maxLen = #v end
        end
        local maxx, maxy = term.getSize()
        if maxLen > maxx - 20 then
                error( 'largest string is too large', 2 )
        end
        local centerx = math.ceil( maxx/2 )
        local centery
        local yValue = {}
        local page = 1
        local selected = math.ceil( #pages[ page ] / 2 )
        local function render()
                local tbl = pages[ page ]
                centery = (maxy/2) - #tbl/2
                term.clear()
                term.setCursorPos( centerx - #title/2 + 1, 2 )
                term.write( title )
                for i = 1, #tbl do
                        term.setCursorPos( centerx - (#tbl[i]/2), centery + i )
                        yValue[ i ] = centery + i
                        term.write( tbl[ i ] )
                end
                if pages[ page - 1 ] then
                        term.setCursorPos( 3, centery + #tbl/2 + 1 )
                        term.write( "previous" )
                end
                if pages[ page + 1 ] then
                        term.setCursorPos( maxx - 5, centery + #tbl/2 + 1 )
                        term.write( "next" )
                end
                local str = "(" .. page .. "/" .. #pages .. ")"
                term.setCursorPos( centerx - (#str/2), maxy )
                term.write( str )
        end
        while true do
                render()
                if debug then
                        term.setCursorPos( 1, 1 )
                        term.write( selected )
                        term.setCursorPos( 1, 2 )
                        term.write( page )
                end
                if term.isColor() then
                        term.setTextColor( colors.yellow )
                end
                if selected == "previous" and not pages[ page - 1 ] then
                        selected = math.ceil( #pages[ page ]/2 )
                elseif selected == "next" and not pages[ page + 1 ] then
                        selected = math.ceil( #pages[ page ]/2 )
                end
                if type( selected ) == "number" then
                        term.setCursorPos( centerx - (#pages[page][selected]/2) - 3, yValue[ selected ] )
                        term.write( "[" )
                        term.setCursorPos( centerx + (#pages[page][selected]/2) + 2, yValue[ selected ] )
                        term.write( "]" )
                elseif selected == "previous" then
                        term.setCursorPos( 1, centery + #pages[ page ]/2 + 1 )
                        term.write( "[" )
                        term.setCursorPos( 12, centery + #pages[ page ]/2 + 1 )
                        term.write( "]" )
                elseif selected == "next" then
                        term.setCursorPos( maxx - 7, centery + #pages[ page ]/2 + 1 )
                        term.write( "[" )
                        term.setCursorPos( maxx, centery + #pages[ page ]/2 + 1 )
                        term.write( "]" )
                end
                if term.isColor() then
                        term.setTextColor( colors.white )
                end
                local event, key = os.pullEvent( "key" )
                local old = selected
                if key == 200 and type( selected ) == "number" and pages[ page ][ selected - 1 ] then
                        selected = selected - 1
                elseif key == 208 and type( selected ) == "number" and pages[ page ][ selected + 1 ] then
                        selected = selected + 1
                elseif key == 28 then
                        if type( selected ) == "number" then
                                return pages[ page ][ selected ]
                        elseif selected == "next" and pages[ page + 1 ] then
                                page = page + 1
                        elseif selected == "previous" and pages[ page - 1 ] then
                                page = page - 1
                        end
                elseif key == 203 then
                        if selected == "next" then
                                selected = math.ceil( #pages[ page ]/2 )
                        elseif type( selected ) == "number" and pages[ page - 1 ] then
                                selected = "previous"
                        end
                elseif key == 205 then
                        if selected == "previous" then
                                selected = math.ceil( #pages[ page ]/2 )
                        elseif type( selected ) == "number" and pages[ page + 1 ] then
                                selected = "next"
                        end
                end
        end
end

umenu = statemachine.unblock( menu )

local tPrograms = {}

local function cleanNils(t)
    local ans = {}
    for _,v in pairs(t) do
        ans[ #ans+1 ] = v
    end
    return ans
end

local function addProgram( window, program, monitorName )
    local prgm = {}
    prgm.func = statemachine.unblock( loadfile( program ) )
    prgm.win = window
    prgm.monName = monitorName
    tPrograms[ #tPrograms + 1 ] = prgm
end

local tMonitors = {}

peripheral.find( "monitor", function( name, object )
    tMonitors[ #tMonitors + 1 ] = name
end )

local dofile = function( str )
    local fn = loadfile( str, getfenv() )
    return fn()
end

local function extendHorizantal( name1, name2 )
    local stitch = dofile( "stitch" )
    local list = {
        { name1, name2 }
    }
    stitch.setMonitors( list )
    return stitch
end

local function extendVertical( name1, name2 )
    local stitch = dofile( "stitch" )
    local list = {
        {name1},
        {name2}
    }
    stitch.setMonitors( list )
    return stitch
end

local curTerm = term.current()
local focus = 1
local shift = false
local control = false
local in_window_menu = false
local to_merge = nil

local input_events = {
    ["char"] = true,
    ["key"] = true,
    ["key_up"] = true,
    ["paste"] = true,
    ["terminate"] = true,
}

local function runMenu()
    local complete, option
    if tPrograms[focus].monName then
        complete, option = umenu( "Options", "Merge Vertically", "Merge Horizantally", "Split", "Exit" )
    else
        complete, option = umenu( "Options", "Split", "Exit" )
    end
    if complete then
        if option == "Split" then
            local w, h = tPrograms[focus].win.getSize()
            w = math.floor( w / 2 )
            h = math.floor( h / 2 )
            local win = window.create(tPrograms[focus].win, 1, 1, w, h )
            addProgram( win, "rom/programs/shell.lua" )
            local win = window.create(tPrograms[focus].win, 1, 1 + h, w, h )
            addProgram( win, "rom/programs/shell.lua" )
            local win = window.create( tPrograms[focus].win, 1 + w, 1, w, h )
            addProgram( win, "rom/programs/shell.lua" )
            local win = window.create( tPrograms[focus].win, 1 + w, 1 + h, w, h )
            addProgram( win, "rom/programs/shell.lua" )
        end

        if option == "Merge Vertically" and not to_merge then
            to_merge = tPrograms[ focus ]
        elseif option == "Merge Vertically" and to_merge then
            local win = extendVertical( to_merge.monName, tPrograms[ focus ].monName )
            addProgram( win, "rom/programs/shell.lua" )
            to_merge = nil
        end

        if option == "Merge Horizantally" and not to_merge then
            to_merge = tPrograms[ focus ]
        elseif option == "Merge Horizantally" and to_merge then
            local win = extendHorizantal( to_merge.monName, tPrograms[ focus].monName )
            addProgram( win, "rom/programs/shell.lua" )
            to_merge = nil
        end
        tPrograms[focus] = nil
        in_window_menu = false
    end
end

statemachine.setLoop( function()
    local event, key = statemachine.pullEvent()
    if event == "terminate" then
        return true
    end

    if key == keys.rightShift or key == keys.leftShift then
        if event == "key" then
            shift = true
        elseif event == "key_up" then
            shift = false
        end
    end

    if key == keys.rightCtrl or key == keys.leftCtrl then
        if event == "key" then
            control = true
        elseif event == "key_up" then
            control = false
        end
    end

    if event == "key" and key == keys.tab then
        if shift then
            --change process
            focus = focus + 1
            if not tPrograms[ focus ] then
                focus = 1
            end
            --print( "focus is now " .. focus )
        elseif control then
            -- open window control menu
            in_window_menu = true
        end
    end

    if #tPrograms == 0 then
        addProgram( curTerm, "rom/programs/shell.lua" )
    end

    if input_events[ event ] then
        term.redirect( tPrograms[ focus ].win )
        if in_window_menu then
            runMenu()
        else
            local complete = tPrograms[ focus ].func()
            if complete then
                tPrograms[ focus ].func = loadfile( "rom/programs/shell.lua" )
            end
        end
    else
        for i = 1, #tPrograms do
            term.redirect( tPrograms[i].win )
            local complete = tPrograms[i].func()
            if complete then
                tPrograms[ i ].func = loadfile( "rom/programs/shell.lua" )
            end
        end
    end
    tPrograms = cleanNils( tPrograms )
    if not tPrograms[ focus ] then
        focus = 1
    end
    term.redirect( curTerm )
end)

addProgram( curTerm, "rom/programs/shell.lua" )

peripheral.find( "monitor", function( k, v )
    v.clear()
    v.setCursorPos( 1, 1 )
    addProgram( v, "rom/programs/shell.lua", k )
end )

statemachine.run()