vn/choice.lua

---Defines functions for allowing a user to select from a list of options
-- 
module("vn.choice", package.seeall)

---Choice screen registry
-------------------------------------------------------------------------------------------------------------- @section registry

local choiceScreenConstructor = nil

---Registers a choice screen creation function. When the choice function is called, the registered constructor
-- function is called to create a new choice screen. The choice screen created must implement the standard
-- choice screen methods (see ChoiceScreen)
function registerChoiceScreen(constructor)
    choiceScreenConstructor = constructor
end

---Choice functions
-------------------------------------------------------------------------------------------------------------- @section choice functions

---Asks the user to select an option.
-- @string ... Any number of strings to use as options. Example use:
--         <code>choice("First option", "Second option")</code>
-- @treturn number The index of the selected option (starting at <code>1</code>).
function choice(...)
    return choice2(getScriptPos(1), ...)
end

---Asks the user to select an option.
-- @param uniqueChoiceId[opt=nil] Unique identifier of the choice, or nil to not track the selected options for this
--                                choice.
-- @string ... Any number of strings to use as options. Example use:
--         <code>choice("First option", "Second option")</code>
-- @treturn number The index of the selected option (starting at <code>1</code>).
function choice2(uniqueChoiceId, ...)
    local options = getTableOrVarArg(...)
    if options == nil or #options == 0 then
        options = {"Genuflect"}
    end

if getSkipMode() == SkipMode.SCENE then
        stopSkipping()
    end

local selected = 1
    if choiceScreenConstructor == nil then
        Log.warn("No choice screen registered")
    else
        if uniqueChoiceId ~= nil then
            Seen.registerChoice(uniqueChoiceId, #options)
        end

local screen = choiceScreenConstructor()
        selected = screen:choose(uniqueChoiceId, options)
        screen:destroy()

if uniqueChoiceId ~= nil then
            Seen.markChoiceSelected(uniqueChoiceId, selected)
        end
    end
    return selected
end

---Default choice screen
-------------------------------------------------------------------------------------------------------------- @section default choice screen

ChoiceScreen = {
    seenStyle=nil --Text style extension for previously selected choices
}

function ChoiceScreen.new(self)
    self = extend(ChoiceScreen, self)
    
    self.seenStyle = self.seenStyle or Text.createStyle{color=0xFF808080}
    
    return self
end

function ChoiceScreen:destroy()
end

---Show the user a selection screen
-- @param[opt=nil] uniqueChoiceId Unique identifier for the script location from which this choice screen was
--        triggered.
-- @param options Table of styled text option descriptions.
function ChoiceScreen:choose(uniqueChoiceId, options)
    if #options == 0 then
        return
    end

Log.info("Showing choice screen (id={}): {}", uniqueChoiceId, table.concat(options, ", "))

local panel = gridPanel()
    local pad = 100
    -- Limit choice button width (looks nicer)
    local width = math.min(screenWidth, screenHeight * 1.25) - pad * 2
    panel:setBounds((screenWidth - width) / 2, pad, width, screenHeight - pad * 2)

local buttons = {}
    for i,option in ipairs(options) do
        local b = button("gui/button")
        b:setZ(-1000)

local styledText = option
        if uniqueChoiceId ~= nil and Seen.hasSelectedChoice(uniqueChoiceId, i) then
            --Apply a custom text style if the user has selected this choice before
            styledText = Text.createStyledText(option, self.seenStyle)
        end
        b:setText(styledText)
        buttons[i] = b

panel:add(b):growX()
        panel:endRow()
    end
    panel:pack()

local selected = 0
    while selected == 0 do
        for i,b in ipairs(buttons) do
            if b:consumePress() then
                selected = i
            end
        end
        yield()
    end
    panel:destroy()
    
    Log.info("Choice selected (id={}): [{}] {}", uniqueChoiceId, selected, options[selected])
    
    return selected
end

registerChoiceScreen(ChoiceScreen.new)