local DonBG               = require("background/bg_objects/donbg")
local BGNormal            = require("background/bg_objects/bg_normal")
local BGFever             = require("background/bg_objects/bg_fever")
local Fever               = require("background/bg_objects/fever")
local Footer              = require("background/bg_objects/footer")
local Dancer              = require("background/bg_objects/dancer")
local RendaController     = require("background/bg_objects/renda")
local ChibiController     = require("background/bg_objects/chibi")

local PracticeBackground  = require("background/bg_collabs/practice")
local TutorialBackground  = require("background/bg_collabs/tutorial")
local A3Background        = require("background/bg_collabs/a3")
local AnimalBackground    = require("background/bg_collabs/animal")
local ButtoBackground     = require("background/bg_collabs/buttoburst")
local DanBackground       = require("background/bg_collabs/dan")
local DQ10Background      = require("background/bg_collabs/dq10")
local FunassyiBackground  = require("background/bg_collabs/funassyi")
local ImasBackground      = require("background/bg_collabs/imas")
local ImasSidemBackground = require("background/bg_collabs/imas_sidem")
local OshiriBackground    = require("background/bg_collabs/oshiri")

local COLLABS             = {
    PRACTICE   = { PracticeBackground.new, nil, 1 },
    TUTORIAL   = { TutorialBackground.new, nil, 1 },
    A3         = { A3Background.new, "background/collab/a3", 4 },
    ANIMAL     = { AnimalBackground.new, "background/collab/animal", 5 },
    BUTTOBURST = { ButtoBackground.new, "background/collab/buttoburst", 4 },
    DAN        = { DanBackground.new, "background/collab/dan", 1 },
    DQ10       = { DQ10Background.new, "background/collab/dq10", 5 },
    FUNASSYI   = { FunassyiBackground.new, "background/collab/funassyi", 5 },
    IMAS       = { ImasBackground.new, "background/collab/imas", 5 },
    IMAS_CG    = { ImasBackground.new, "background/collab/imas_cg", 3 },
    IMAS_ML    = { ImasBackground.new, "background/collab/imas_ml", 3 },
    IMAS_SIDEM = { ImasSidemBackground.new, "background/collab/imas_sidem", 3 },
    OSHIRI     = { OshiriBackground.new, "background/collab/oshiri", 5 },
}

Background                = {}
Background.__index        = Background

function Background.new(player_num, bpm, scene_preset)
    local self        = setmetatable({}, Background)

    self.player_num   = player_num
    self.bpm          = bpm
    self.scene_preset = scene_preset
    self.is_2p        = (player_num == 3) -- PlayerNum::TWO_PLAYER

    tex.load_animations("background")

    local entry = scene_preset and COLLABS[scene_preset]
    if entry then
        local ctor, path, max_dancers = entry[1], entry[2], entry[3]
        if path then
            self.collab = ctor(player_num, bpm, path, max_dancers)
        else
            self.collab = ctor(player_num, bpm)
        end
    else
        -- Standard (non-collab) case
        local max_dancers = 5
        self.max_dancers  = max_dancers

        if self.is_2p then
            local donbg_index = math.random(1, 6)
            self.donbg_1      = DonBG.create(1, "background", donbg_index)
            self.donbg_2      = DonBG.create(2, "background", donbg_index)
            local skin_cfg    = tex.get_skin_config("game_2p_offset")
            self.p2_y_offset  = skin_cfg and skin_cfg.y or 0
            self.is_clear_1   = false
            self.is_clear_2   = false
        else
            self.donbg     = DonBG.create(player_num, "background")
            self.bg_normal = BGNormal.create(math.random(0, 4), "background")
            self.bg_fever  = BGFever.create(math.random(0, 3), "background")
            self.fever     = Fever.create(math.random(0, 3), bpm, "background")
            self.dancer    = Dancer.create(math.random(0, 20), bpm, "background", max_dancers)
            self.footer    = Footer.new("background", math.random(0, 2))
        end

        self.renda          = RendaController.new("background", math.random(0, 2))
        self.chibi          = ChibiController.new(bpm, "background")
        self.is_clear       = false
        self.is_rainbow     = false
        self.last_milestone = 1
    end

    return self
end

function Background:update(current_ms, bpm)
    self.bpm = bpm
    if self.collab then
        self.collab:update(current_ms, bpm)
    else
        if self.is_2p then
            self.donbg_1:update(current_ms)
            self.donbg_2:update(current_ms)
        else
            self.donbg:update(current_ms)
            self.bg_normal:update(current_ms)
            self.bg_fever:update(current_ms)
            self.fever:update(current_ms, bpm)
            self.dancer:update(current_ms, bpm)
        end
        self.renda:update(current_ms)
        self.chibi:update(current_ms, bpm)
    end
end

function Background:handle_good(player_num)
    if self.collab then
        self.collab:handle_good(player_num)
    else
        self.chibi:add_chibi(player_num, false)
    end
end

function Background:handle_ok(player_num)
    if self.collab then
        self.collab:handle_ok(player_num)
    else
        self.chibi:add_chibi(player_num, false)
    end
end

function Background:handle_bad(player_num)
    if self.collab then
        self.collab:handle_bad(player_num)
    else
        self.chibi:add_chibi(player_num, true)
    end
end

function Background:handle_drumroll(player_num)
    if self.collab then
        self.collab:handle_drumroll(player_num)
    else
        self.renda:add_renda()
    end
end

function Background:handle_balloon(player_num)
    if self.collab then
        self.collab:handle_balloon(player_num)
    else
        self.renda:add_renda()
    end
end

function Background:handle_gauge(player_num, progress, is_clear, is_rainbow)
    if self.collab then
        self.collab:handle_gauge(player_num, progress, is_clear, is_rainbow)
    elseif self.is_2p then
        -- Update each player's donbg clear state independently
        if player_num == 1 then
            self.donbg_1:set_clear(is_clear)
            self.is_clear_1 = is_clear
        elseif player_num == 2 then
            self.donbg_2:set_clear(is_clear)
            self.is_clear_2 = is_clear
        end
        self.is_clear = self.is_clear_1 or self.is_clear_2
        self.is_rainbow = is_rainbow
    else
        self.donbg:set_clear(is_clear)
        if is_clear and not self.is_clear then self.bg_fever:start() end
        if is_rainbow and not self.is_rainbow then self.fever:start() end
        self.is_clear   = is_clear
        self.is_rainbow = is_rainbow

        local md        = self.max_dancers
        local current_milestone
        if is_clear then
            current_milestone = md
        else
            current_milestone = math.min(md - 1, math.floor(progress * md))
        end
        if current_milestone > self.last_milestone then
            for _ = 1, current_milestone - self.last_milestone do self.dancer:add_dancer() end
            self.last_milestone = current_milestone
        elseif current_milestone < self.last_milestone then
            for _ = 1, self.last_milestone - current_milestone do self.dancer:remove_dancer() end
            self.last_milestone = current_milestone
        end
    end
end

function Background:draw_back()
    if self.collab then
        self.collab:draw_back()
    else
        if not self.is_2p then
            if self.is_clear then
                if not self.bg_fever.transitioned then
                    self.bg_normal:draw()
                    self.bg_fever:draw()
                else
                    self.bg_fever:draw()
                end
            else
                self.bg_normal:draw()
            end
        end

        if self.is_2p then
            self.donbg_1:draw(0)
            self.donbg_2:draw(self.p2_y_offset)
        else
            self.donbg:draw()
        end

        self.renda:draw()
        if not self.is_2p then
            self.dancer:draw()
            self.footer:draw()
            if self.is_rainbow then self.fever:draw() end
        end
        self.chibi:draw()
    end
end

function Background:draw_fore()
    if self.collab then
        self.collab:draw_fore()
    end
end

function Background:destroy()
    if self.collab then
        self.collab:destroy()
    else
        if self.is_2p then
            self.donbg_1:destroy()
            self.donbg_2:destroy()
        else
            self.donbg:destroy()
            self.bg_normal:destroy()
            self.bg_fever:destroy()
            self.fever:destroy()
            self.dancer:destroy()
            self.footer:destroy()
        end
        self.renda:destroy()
        self.chibi:destroy()
    end
end