ContextMenu.lua

-- Custom context menu creator for ComputerCraft.
-- Run the following commands before using this file:
--   pastebin get Rac6Jxjg "/API/LibAppend.lua"
--   pastebin get KA2dK07y "/API/Events.lua"
--   pastebin get t2TvSiSU "/API/Class.lua"
--   pastebin get 4hpwn3mn "/API/ContextMenu.lua"
-- Documentation and the changelog for this class can be found below.
require("/API/Events")

ContextMenu = Class(function()
local events = Events() -- Primarily for processing user input.
local pressed = "" -- The name of the menu button currently being pressed.
local buttons = {} -- Positions of buttons.
local disabled = {} -- Functions that check if buttons are disabled.
local dir = {left = {}, right = {}, up = {}, down = {}} -- Names of adjacent buttons.
local pos = vector.new() -- Position of the menu.
local size = vector.new() -- Size of the menu.
local color = {} -- All color values.
local alt = "" -- The button that is selected when 'alt' is pressed.
local win = {} -- The window for the menu.
local ro = {} -- All of the readonly methods/properties for the menu object.

-- Processes the graphics for a button being unpressed.
local unpress = function()
    local button = pressed
    if button ~= "" then
        pressed = ""
        ro.drawButton(button)
    end
end

-- Processes the graphics for a button being pressed.
local press = function(button)
    unpress(pressed)
    if button ~= "" then
        pressed = button
        ro.drawButton(button)
    end
end

-- Checks if a click is within the hitbox of a button.
local checkButtonPress = function(menuPos)
    for a, b in pairs(buttons) do
        local buttonPos = vector.new(menuPos.x-b.x+1, menuPos.y-b.y+1)
        if isBetween(buttonPos.x, 1, a:len(), true) and buttonPos.y == 1 and not disabled[a]() then
            press(a)
            return
        end
    end
    unpress()
end

-- Returns the position of the menu.
ro.getPos = function()
    return pos.x, pos.y
end

-- Returns the size of the menu.
ro.getSize = function()
    return size.x, size.y
end

-- Redraws the specified button.
ro.drawButton = function(button)
    if disabled[button]() then
        win.setBackgroundColor(color.disabled[1])
        win.setTextColor(color.disabled[2])
    elseif pressed == button then
        win.setBackgroundColor(color.pressed[1])
        win.setTextColor(color.pressed[2])
    else
        win.setBackgroundColor(color.default[1])
        win.setTextColor(color.default[2])
    end
    if button:sub(1, 10) == "HSeparator" then
        win.setCursorPos(1, buttons[button].y)
        win.write(string.rep("\140", size.x))
    elseif button:sub(1, 10) == "VSeparator" then
        for y = 1, size.y do
            win.setCursorPos(buttons[button].x, y)
            win.write("\149")
        end
    else
        win.setCursorPos(buttons[button].x, buttons[button].y)
        win.write(button)
    end
end

-- Redraws the whole menu.
ro.drawMenu = function()
    win.setBackgroundColor(color.default[1])
    win.setTextColor(color.default[2])
    win.clear()
    for a, b in pairs(buttons) do
        ro.drawButton(a)
    end
end

-- Processes user input for this menu.
ro.ui = function()
    ro.drawMenu()
    while true do
        local event = events.getEvent()
        if OR(event[1], "mouse_click", "mouse_drag", "mouse_up") and event[2] == 1 then
            local menuPos = vector.new(event[3]-pos.x+1, event[4]-pos.y+1)
            if isBetween(menuPos.x, 1, size.x, true) and isBetween(menuPos.y, 1, size.y, true) then
                checkButtonPress(menuPos)
                if event[1] == "mouse_up" and not(pressed == "" or ro[pressed] == nil or disabled[pressed]()) then
                    ro[pressed]()
                end
            else
                if event[1] == "mouse_click" then
                    events.queueEvent(table.unpack(event))
                    unpress()
                    return
                end
            end
            if event[1] == "mouse_up" then
                unpress()
                return
            end

        elseif event[1] == "key" then
            if OR(event[2], keys.leftAlt, keys.rightAlt) and alt then
                if pressed == "" then
                    press(alt)
                else
                    unpress()
                    os.pullEvent("key_up")
                    return
                end

            elseif OR(event[2], keys.right, keys.left, keys.up, keys.down) then
                if dir[keys.getName(event[2])][pressed] ~= nil then
                    press(dir[keys.getName(event[2])][pressed])
                end
                if pressed == "" then press(alt) end

            elseif OR(event[2], keys.enter, keys.numPadEnter) then
                if not(ro[pressed] == nil or disabled[pressed]()) then
                    ro[pressed]()
                end
                unpress()
                break
            end
        end
    end
end

return {
    ctor = function(data)
        pos, size = data.pos, data.size
        win = window.create(term.current(), pos.x, pos.y, size.x, size.y)
        alt = data.alt
        color = data.color or {}
        color.default = color.default or {colors.lightGray, colors.black}
        color.pressed = color.pressed or {colors.gray, colors.black}
        color.disabled = colors.disabled or {colors.lightGray, colors.gray}

        for a, b in pairs(data.buttons) do
            if ro[a] == nil then ro[a] = b.main
            else error("Cannot use the menu button '" .. a .. "' because it would overwrite an already existing property in this menu.", 2)
            end
            buttons[a] = b.pos
            dir.left[a] = b.left
            dir.right[a] = b.right
            dir.up[a] = b.up
            dir.down[a] = b.down
            if a:sub(2, 10) == "Separator" then disabled[a] = function() return true end
            elseif b.disable == nil then disabled[a] = function() return false end
            else disabled[a] = b.disable end
        end
    end,
    protected = true,
    readOnly = ro
}
end)

--[[ Documentation
local exampleMenu = ContextMenu{
• This is how you create a context menu. You can also put the curly brackets in
  parentheses but this way is less cluttery.

    pos = vector.new(<x position>, <y position>),
    • This is the coordinates on the screen the menu will be drawn.
    • This is required.

    size = vector.new(<width>, <height>),
    • This is the fixed width and height of the menu.
    • This is required.

    alt = <button name>,
    • This is the name of the menu button that will be selected first when the
      menu is opened.
    • This is required.

    color = {
    • These are the colors the menu and buttons will be depending on if a button
      is pressed or disabled or neither.
    • First value is the background color.
    • Second value is the text color.
    • All colors have a default value so none are required.

        default = {<color>, <color>},
        • These are the colors of the whole menu. They are also the colors of
          buttons that are not disabled or pressed.
        • Default background color is 'colors.lightGray'.
        • Default text color is 'colors.black'.

        pressed = {<color>, <color>},
        • These are the colors of buttons that are pressed and not disabled.
        • Default background color is 'colors.gray'.
        • Default text color is 'colors.black'.

        disabled = {<color>, <color>}
        • These are the colors of buttons that are disabled. These buttons can't
          be pressed.
        • Default background color is 'colors.lightGray'.
        • Default text color is 'colors.gray'.

    },
    buttons = {
    • These are the definitions of each button in the menu.
    • This table is required.
    • Technically no buttons are required, but not having at least 1 would make
      the whole menu redundant.

        [<button 1 name>] = {
        • The button name is the key/index of the table element.
        • There are some names that your buttons can't have. See below for more
          info.

            pos = vector.new(<x>, <y>),
            • This is the coordinates relative to the menu where the button will
              be drawn.
            • This is required.

            main = function() ... end,
            • This is the function that runs when the button is pressed.
            • This is not required for separators.
            • This is technically not required for anything else, but not having
              this would make the button redundant.

            disable = function() ... end,
            • This function determines if the button should be disabled.
            • This function must return a boolean saying if the button is
              disabled or not.
            • This is NOT required. By default this will return false.

            up = <button 2 name>,
            • This is the name of the button that will be selected when the up
              key is pressed.
            • This is NOT required.

            down = <button 3 name>,
            • This is the name of the button that will be selected when the down
              key is pressed.
            • This is NOT required.

            left = <button 4 name>,
            • This is the name of the button that will be selected when the left
              key is pressed.
            • This is NOT required.

            right = <button 5 name>,
            • This is the name of the button that will be selected when the
              right key is pressed.
            • This is NOT required.

        },
        [<button 2 name>] = {...},
        • Additional buttons follow the same format as the first one.

        ["HSeparator"] = {...},
        • This will add a horizontal line that stretch's from the left to the
          right of the whole menu.
        • This button will always be disabled and will ignore the 'main'
          function.
        • Make sure your separator's name always starts with "HSeparator". The
          name can have any text after that.
        • If you have more than one separator, each one has to have a different
          name, like "HSeparator1", "HSeparator2", etc.

        [<button 3 name>] = {...},
        [<button 4 name>] = {...},
        ["VSeparator"] = {...},
        • This follows the same rules as "HSeparator", but it draws a vertical
          line from the top to the bottom of the whole menu instead of a
          horizontal one.

        [<button 5 name>] = {...}
    }
}

The following methods are used in the object and therefore are protected. Avoid
naming your buttons the same as any of these methods. Methods are case sensitive
so your button may be the same name as long as capitalization is different.

exampleMenu.getPos()
• This returns the x and y coordinates of the menu.

exampleMenu.getSize()
• This returns the width and height of the menu.

exampleMenu.drawMenu()
• This redraws the whole menu.

exampleMenu.drawButton()
• This redraws a specific menu button.

exampleMenu.ui()
• This enables the menu UI.
]]

--[[ Changelog
2024/01/02:
• Changed all instances of 'vector2' to 'vector' to comply with the changes made
  to 'LibAppend.lua'.
• Removed some commented debugging code.
• Fixed some typos in the documentation.
• Rewrote some parts of the documentation to be more descriptive.
• Changed the color parameter to use a basic array instead of a vector (should
  reduce memory usage).
• Rewrote the 'drawButton' method to flow better. Fixed the vertical separator
  not displaying correctly. Fixed the separators not starting at the top/left
  edges of the menu.
• Removed the 'disable' table because it was unused.
• Replaced/added various comments with more descriptive text.

2023/03/09:
• Completely rewrote this program to comply with the changes made to 'Class.lua'
  and 'Events.lua'.
• Removed the automatic download of required API files. The files must be
  downloaded manually.
• Paste exposure has been returned to public.

2023/02/23:
• Changed require directories from "/API/Raiu/" to "/API/".
• Renamed vector to vector2 to reflect the changes to "/API/LibAppend.lua".
• Reformatted the changelog so it's a bit cleaner than before.
• Changed to unlisted until I can fix the changes made to "/API/events.lua".

2022/07/20:
• Added an example for how to use the menuClass.

2022/07/15:
• Added parameters for custom menu colors.

2022/07/13:
• Added require functions for required APIs so the main program doesn't have to.

2022/06/29:
• Updated eventListener() to events.listen().

2022/06/28:
• Completely rewrote the ui and graphical code (twice). Old code was a complete
  mess and unintuitive.
• With the new code, everything is handled within the context menu class.
• Now works with both mouse clicks and key presses.
]]