local ease = require "lib.utils.easing"
local AnimationNode = require "lib.animation_node"

--- @alias SourceFilter { type: "bandpass"|"highpass"|"lowpass", volume: number, highgain: number, lowgain: number }

--- @class Audio
--- @field musicVolume number
--- @field soundVolume number
--- @field looped boolean
--- @field animationNode AnimationNode?
--- @field from love.Source?
--- @field to love.Source?
audio = {}
audio.__index = audio

--- здесь мы должны выгружать значения из файлика с сохранением настроек
local function new(musicVolume, soundVolume)
    return setmetatable({
        musicVolume = musicVolume,
        soundVolume = soundVolume,
        looped = true
    }, audio)
end

function audio:update(dt)
    if self.animationNode and self.animationNode.state == "running" then
        self.animationNode:update(dt)
        self.from:setVolume(self.musicVolume - self.animationNode:getValue() * self.musicVolume)
        self.to:setVolume(self.animationNode:getValue() * self.musicVolume)
        -- print(self.animationNode.t)
    elseif self.animationNode and self.animationNode.state == "finished" then
        self.from:stop()
        self.animationNode:finish()
        self.animationNode = nil
    end
end

--- if from is nil, than we have fade in to;
--- if to is nil, than we have fade out from
---
--- also we should guarantee, that from and to have the same volume
--- @param from love.Source
--- @param to love.Source
--- @param ms number? in milliseconds
function audio:crossfade(from, to, ms)
    print("[Audio]: Triggered crossfade")
    self:play(to)
    to:setVolume(0)
    self.from = from
    self.to = to
    self.animationNode = AnimationNode {
        function(node) end,
        onEnd = function()
            self.from:setVolume(0)
            self.to:setVolume(self.musicVolume)
            print("[Audio]: Crossfade done")
        end,
        duration = ms or 1000,
        easing = ease.easeOutCubic,
    }
    self.animationNode:run()
end

--- @param source love.Source
--- @param settings SourceFilter?
function audio:play(source, settings, effectName)
    if settings then
        source:setFilter(settings)
    end
    source:setEffect(effectName, true)
    if source:getType() == "stream" then
        source:setLooping(self.looped)
        source:setVolume(self.musicVolume)
        return source:play()
    end
    source:setVolume(self.soundVolume)
    return source:play()
end

function audio:setMusicVolume(volume)
    self.musicVolume = volume
end

function audio:setSoundVolume(volume)
    self.soundVolume = volume
end

return { new = new }