Turti Lib Scroll View

local scrollViews = {}

local function scrollListener()
    while true do
        local _, scrollDirection, x, y = os.pullEvent("mouse_scroll")
        printPoly(scrollDirection, x, y)
    end
end

local function registerScrollView(view)
    local context = getClassContext(view)

    for _, registeredView in ipairs(scrollViews) do
        if rectsOverlap(context.x, context.y, context.w, context.h,
                registeredView.x, registeredView.y, registeredView.w, registeredView.h) then
            error("scroll view overlaps with another scroll view")
        end
    end

    table.insert(scrollViews, {
        view = view,
        x = context.x,
        y = context.y,
        w = context.w,
        h = context.h
    })
end

local function disposeScrollView(view)
    for i = 0, #scrollViews do
        if scrollViews[i] == view then
            table.remove(scrollViews, i)
            return
        end
    end
end

local ScrollViewClass
ScrollViewClass = {
    key = "ScrollView",
    methods = {
        dispose = function(view, context)
            disposeScrollView(view)
        end,
        print = function(view, context, ...)
            printPolyTo(function(txt)
                ScrollViewClass.privateMethods.write(view, context, txt)
            end, ...)
            ScrollViewClass.privateMethods.render(context)
        end,
        clear = function(view, context)
            context.lines = { "" }
            context.currentLine = 1
            context.viewOffset = 0
        end
    },
    privateMethods = {
        write = function(view, context, txt)
            local first = true
            local pts = splitText(txt, "\n\r", false, false, true)
            for _, pt in ipairs(pts) do
                if first then
                    first = false
                else
                    table.insert(context.lines, "")
                    context.currentLine = context.currentLine + 1
                end
                local line = context.lines[context.currentLine]
                local newLine = line .. pt
                while #newLine > context.w do
                    context.lines[context.currentLine] = newLine:sub(1, context.w)
                    newLine = newLine:sub(context.w + 1)
                    table.insert(context.lines, "")
                    context.currentLine = context.currentLine + 1
                end
                context.lines[context.currentLine] = newLine
            end
        end,
        render = function(context)
            if not test then
                local x, y = term.getCursorPos()
                for i = 1, context.h do
                    local screenLine = context.viewOffset + i
                    term.setCursorPos(context.x + 1, screenLine)
                    term.clearLine()
                    term.setCursorPos(context.x + 1, screenLine)
                    if i <= context.currentLine then
                        write(context.lines[i])
                    end
                end
                term.setCursorPos(x, y)
            else
                for i = 1, context.h do
                    if i <= context.currentLine then
                        print("render line [" .. context.lines[i] .. "]")
                    end
                end
                print("")
            end
        end
    },
    construct = function(view, context, x, y, w, h)
        if not x or not y or not w or not h then
            error("missing arguments (x, y, w, h expected)")
        end
        context.x = x
        context.y = y
        context.w = w
        context.h = h
        ScrollViewClass.methods.clear(view, context)
        registerScrollView(view)
        if not test then
            local _, y1 = term.getCursorPos()
            if context.y <= y1 - 1 and y1 - 1 < context.y + context.h then
                term.setCursorPos(1, context.y + context.h)
            end
        end
    end
}

return {
    name = "scrollView",
    onSetup = function()
        ThreadManager.startThread(
                scrollListener, true, "scroll view listener"
        )
    end,
    classes = {
        ScrollViewClass
    }
}