heroes-of-nerevelon/lib/simple_ui/level_layout.lua

local icons = require("lib.utils.sprite_atlas").load(Tree.assets.files.dev_icons)
local AnimationNode = require "lib.animation_node"

--- @class UIElement
local uiElement = {
    x = 0,
    y = 0,
    width = 0,
    height = 0,
    transform = love.math.newTransform()
}
uiElement.__index = uiElement

function uiElement:update(dt) end

function uiElement:draw() end

function uiElement:show(animationNode) end

function uiElement:hide(animationNode) end

function uiElement:hitTest(screenX, screenY)
    local lx, ly = self.transform:inverseTransformPoint(screenX, screenY)
    local belongs = function(value, lower, upper)
        return value >= lower and value < upper
    end
    return belongs(lx, self.x, self.x + self.width) and belongs(ly, self.y, self.y + self.height)
end

--- @class _SkillButton : UIElement
--- @field showNode AnimationNode?
--- @field showT number
--- @field hovered boolean
--- @field selected boolean
--- @field onClick function?
--- @field icon string
local skillButton = setmetatable({}, uiElement)
skillButton.__index = skillButton

function skillButton.new(icon)
    return setmetatable({
        icon = icon
    }, skillButton)
end

local function easeIn(x)
    return x * x * x
end

function skillButton:update(dt)
    local mx, my = love.mouse.getPosition()
    if self:hitTest(mx, my) then
        self.hovered = true
        if Tree.controls:isJustPressed("select") then
            if self.onClick then self.onClick() end
            Tree.controls:consume("select")
        end
    else
        self.hovered = false
    end

    if self.showT < 300 then
        self.showT = self.showT + dt * 1000
        self.y = 10 * easeIn(-1 + self.showT / 300)
        return
    end
    if self.showNode then
        self.showNode:finish()
        self.showNode = nil
    end
end

--- @param animationNode AnimationNode
function skillButton:show(animationNode)
    if self.showNode then
        self.showNode:finish()
    end
    self.showT = 0
    self.showNode = animationNode
end

function skillButton:draw()
    love.graphics.push()
    love.graphics.applyTransform(self.transform)
    local alpha = self.showT / 300

    if self.selected then
        love.graphics.setColor(0.3, 1, 0.3, alpha)
    elseif self.hovered then
        love.graphics.setColor(0.7, 1, 0.7, alpha)
    else
        love.graphics.setColor(1, 1, 1, alpha)
    end

    love.graphics.translate(0, self.y)
    love.graphics.draw(icons.atlas, icons:pickQuad(self.icon))
    love.graphics.setColor(1, 1, 1)
    love.graphics.pop()
end

--- @class _SkillRow : UIElement
--- @field characterId Id
--- @field children _SkillButton[]
local skillRow = setmetatable({}, uiElement)
skillRow.__index = skillRow

--- @param characterId Id
function skillRow.new(characterId)
    local t = {
        characterId = characterId,
        children = {}
    }
    local char = Tree.level.characters[characterId]
    char:try(Tree.behaviors.spellcaster, function(behavior)
        for i, spell in ipairs(behavior.spellbook) do
            local skb = skillButton.new(spell.tag)
            skb.onClick = function()
                skb.selected = not skb.selected

                if not behavior.cast then
                    behavior.cast = behavior.spellbook[i]
                    behavior.state = "casting"
                else
                    behavior.state = "idle"
                    behavior.cast = nil
                end
            end
            t.children[i] = skb
        end
    end)

    return setmetatable(t, skillRow)
end

function skillRow:show()
    for _, skb in ipairs(self.children) do
        AnimationNode {
            function(animationNode)
                skb:show(animationNode)
            end,
        }:run()
    end
end

function skillRow:update(dt)
    local iconSize = icons.tileSize
    local scale = (64 / iconSize)
    local screenW, screenH = love.graphics.getDimensions()
    local padding = 8
    local count = #self.children
    self.width, self.height, self.x, self.y = count * icons.tileSize + (count - 1) * padding, iconSize, 0,
        0 -- в локальных координатах

    self.transform = love.math.newTransform():translate(screenW / 2,
        screenH - 16):scale(scale, scale):translate(-self.width / 2, -iconSize)

    for i, skb in ipairs(self.children) do
        skb.width, skb.height = iconSize, iconSize
        skb.transform = self.transform:clone():translate(self.x + (i - 1) * iconSize +
            (i - 1) *
            padding, -- левый край ряда + размер предыдущих иконок + размер предыдущих отступов
            0        -- высота не меняется
        )
        skb:update(dt)
    end
end

function skillRow:draw()
    for _, skb in ipairs(self.children) do
        skb:draw()
    end
end

local layout = {}
function layout:update(dt)
    local cid = Tree.level.selector:selected()
    if cid then
        self.skillRow = skillRow.new(cid)
        self.skillRow:show()
    end
    if Tree.level.selector:deselected() then self.skillRow = nil end
    if self.skillRow then self.skillRow:update(dt) end
end

function layout:draw()
    if self.skillRow then self.skillRow:draw() end
end

return layout