local Button = Object:extend()
local ButtonCircle = Object:extend()
local TweenManager = require "birb.classes.time"

local keys = {"A", "B", "C", "select", "up", "down", "left", "right"}
local BTN_SIZE = 21
local CANVAS_SIZE = 21+2
local SHAKETIME = 0.02
local SHAKEPOWER = 4

local function myStencilFunction()
    love.graphics.circle("fill", CANVAS_SIZE/2, CANVAS_SIZE/2, BTN_SIZE/2 - 1)
 end

function Button:new(prompt, key, number, beginTime)
    self.prompt = prompt
    self.key = key
    self.number = number or 1
    self.showNumber = (self.number > 1)

    self.isPressed = false

    self.lum = 1
    self.opacity = 0
    self.frame = self:getFrame()
    self.scale = 1.25
    self.isFailed = false
    self.shakeTimer = SHAKETIME
    self.shakex, self.shakey = 0, 0
    self.circles = {}

    self.timerTexture = nil
    self.tweens = TweenManager(self)
    self.tweens:newTween(0, beginTime, {opacity = 1, scale = 1}, "inOutQuart")
end

function Button:getFrame()
    for i, key in ipairs(keys) do
        if (key == self.key) then
            return i
        end
    end
    error("Non existing key " .. self.key)
end

function Button:update(dt, isFirst)
    self.tweens:update(dt)
    for i, circle in ipairs(self.circles) do
        circle:update(dt)
    end

    if (self.isFailed) then
        self.shakeTimer = self.shakeTimer - dt
        if (self.shakeTimer < 0) then
            self.shakeTimer = SHAKETIME
            self.shakex = math.random(SHAKEPOWER*2) - (SHAKEPOWER)
            self.shakey = math.random(SHAKEPOWER*2) - (SHAKEPOWER)
        end
    end

    if (isFirst) then
        self.timerTexture = love.graphics.newCanvas(CANVAS_SIZE, CANVAS_SIZE)
        love.graphics.setCanvas({self.timerTexture, stencil = true})
        love.graphics.setColor(0.5, 0.5, 0.5, 1)
        love.graphics.circle("fill", CANVAS_SIZE/2, CANVAS_SIZE/2, BTN_SIZE/2)
        utils.graphics.setColorHSV(self.prompt:getTimer()/3, 1, 1)
        love.graphics.stencil(myStencilFunction, "replace", 1)
        love.graphics.setStencilTest("greater", 0)
        love.graphics.arc("fill", CANVAS_SIZE/2, CANVAS_SIZE/2, BTN_SIZE/2, 0 - (math.pi/2), ((math.pi*2*self.prompt:getTimer()) - (math.pi/2)), 16)
        love.graphics.setStencilTest()
        love.graphics.setCanvas()
    end
end

function Button:verifyPrompts(sourceKeys, removeWhenPressed)
    local mustBeRemoved = false
    local keyValue = 0
    self.lum = 1
    for i, key in ipairs(keys) do
        if (sourceKeys[key].isPressed) then
            if (key == self.key) then
                keyValue = 1
                self.lum = 0.8
                table.insert(self.circles, ButtonCircle())
            else
                keyValue = -1
                self.isFailed = true
            end
        end
    end
    if (removeWhenPressed and keyValue == 1) then
        self.number = self.number - 1
        if (self.number == 0) then
            mustBeRemoved = true
        end
    end
    return keyValue, mustBeRemoved
end

function Button:finish(success)
    local scale = 0.75
    if (success == true) then
        scale = 1.25
    end
    self.tweens:newTween(0, 0.15, {opacity = 0, scale = scale}, "inOutQuart")
end

function Button:draw(x, y, isFirst)
    local x, y = x + self.shakex, y + self.shakey
    love.graphics.setColor(1,1,1,self.circleOpacity)
    for i, circle in ipairs(self.circles) do
        circle:draw(x, y)
    end
    love.graphics.setColor(self.lum,self.lum,self.lum,self.opacity)
    if (isFirst and self.timerTexture ~= nil) then
        love.graphics.draw(self.timerTexture, x, y, 0, -self.scale, self.scale, 12, 11)
    end
    self.prompt.assets.tileset["qtebtn"]:drawTile(self.frame, x, y, 0, self.scale, self.scale, 8, 8)
    love.graphics.setColor(1,1,1,1)
    if (self.number > 0 and self.showNumber) then
        self.prompt.assets.fonts["hudnbrs_small"]:draw(utils.math.numberToString(self.number, 2), x, y + 2, -1, "left")
    end
end

function ButtonCircle:new()
    self.radius = 6
    self.opacity = 1
    self.tweens = TweenManager(self)
    self.tweens:newTween(0, 0.2, {radius = 12}, "inOutQuart")
    self.tweens:newTween(0.1, 0.1, {opacity = 0}, "inOutQuart")
end

function ButtonCircle:update(dt)
    self.tweens:update(dt)
end

function ButtonCircle:draw(x, y)
    love.graphics.setColor(1,1,1,self.opacity)
    love.graphics.circle("line",x,y,self.radius, 16)
end

return Button