local DonBGBase = require("Skins/PyTaikoGreen/Scripts/bg_objects/donbg/base")
local Dancer    = require("Skins/PyTaikoGreen/Scripts/bg_objects/dancer")
local RendaController = require("Skins/PyTaikoGreen/Scripts/bg_objects/renda")
local ChibiController = require("Skins/PyTaikoGreen/Scripts/bg_objects/chibi")

local COLLAB_PATH = "background/collab/a3"
local MAX_DANCERS = 4

-- Custom DonBG: looping screen-width tile scroll
local A3DonBG = setmetatable({}, {__index = DonBGBase})
A3DonBG.__index = A3DonBG

function A3DonBG.new(player_num)
    local self = setmetatable({}, A3DonBG)
    local base = DonBGBase.new(1, player_num, COLLAB_PATH)
    for k, v in pairs(base) do self[k] = v end
    self.move = anim.move(10000, {total_distance = -tex.get_screen_width(), loop = true})
    return self
end

function A3DonBG:draw_textures(fade, y, frame)
    local sw = tex.get_screen_width()
    local sc = tex.get_screen_scale()
    for i = 0, math.floor(2 * sc) - 1 do
        tex.draw_texture(self.name, "background", {
            frame = frame, fade = fade,
            x = (i * sw) + self.move.attribute
        })
    end
end

-- BGNormal: flicker overlay (anim 9) + curtain
local A3BGNormal = {}
A3BGNormal.__index = A3BGNormal

function A3BGNormal.new()
    local self = setmetatable({}, A3BGNormal)
    self.name = "bg_0"
    tex.load_folder(COLLAB_PATH, "bg_normal/" .. self.name)
    self.flicker = tex.get_animation(9)
    return self
end

function A3BGNormal:update(current_time_ms)
    self.flicker:update(current_time_ms)
end

function A3BGNormal:draw()
    tex.draw_texture(self.name, "background")
    tex.draw_texture(self.name, "overlay", {fade = self.flicker.attribute})
    tex.draw_texture(self.name, "curtain")
end

function A3BGNormal:destroy()
    tex.unload_folder(COLLAB_PATH, "bg_normal/" .. self.name)
end

-- BGFever: extends BGFever4 pattern with petals tiling
-- Uses anims 16-18 for slide-in (same as BGFever3/Python BGFever4),
-- then a new looping vertical_move (duration 1300 = anim 15 duration) for petals.
local A3BGFever = {}
A3BGFever.__index = A3BGFever

function A3BGFever.new()
    local self = setmetatable({}, A3BGFever)
    self.name = "bg_fever_0"
    tex.load_folder(COLLAB_PATH, "bg_fever/" .. self.name)
    self.transitioned = false
    self.horizontal_move      = tex.get_animation(16)
    self.bg_texture_move_down = tex.get_animation(17)
    self.bg_texture_move_up   = tex.get_animation(18)
    local petal_info = tex.get_texture_info(self.name, "petals")
    self.petal_width = petal_info and petal_info.width or 0
    self.vertical_move = anim.move(1300, {total_distance = self.petal_width, loop = true})
    return self
end

function A3BGFever:start()
    self.bg_texture_move_down:start()
    self.bg_texture_move_up:start()
end

function A3BGFever:update(current_time_ms)
    self.bg_texture_move_down:update(current_time_ms)
    self.bg_texture_move_up:update(current_time_ms)
    if self.bg_texture_move_up.is_finished and not self.transitioned then
        self.transitioned = true
        self.horizontal_move:restart()
    end
    if self.transitioned then
        self.horizontal_move:update(current_time_ms)
    end
    self.vertical_move:update(current_time_ms)
end

function A3BGFever:draw()
    local sc = tex.get_screen_scale()
    local w = self.petal_width
    tex.draw_texture(self.name, "overlay")
    for i = 0, math.floor(10 * sc) - 1 do
        for j = 0, 1 do
            tex.draw_texture(self.name, "petals", {
                x = (i * w) - self.horizontal_move.attribute,
                y = (j * w) + self.vertical_move.attribute
            })
        end
    end
end

function A3BGFever:destroy()
    tex.unload_folder(COLLAB_PATH, "bg_fever/" .. self.name)
end

-- Custom Dancer: BaseDancer + shadow overlay
local BaseDancer = Dancer.Base

local A3Dancer = setmetatable({}, {__index = BaseDancer})
A3Dancer.__index = A3Dancer

function A3Dancer.new(name, index, bpm)
    local self = setmetatable({}, A3Dancer)
    local base = BaseDancer.new(name, index, bpm)
    for k, v in pairs(base) do self[k] = v end
    return self
end

function A3Dancer:draw(x)
    BaseDancer.draw(self, x)
    tex.draw_texture(self.name, "shadow", {x = x, fade = 0.50})
end

-- Background

local A3Background = {}
A3Background.__index = A3Background

function A3Background.new(player_num, bpm)
    local self = setmetatable({}, A3Background)
    self.donbg     = A3DonBG.new(player_num)
    self.bg_normal = A3BGNormal.new()
    self.bg_fever  = A3BGFever.new()
    self.dancer    = Dancer.BaseDancerGroup.new(0, bpm, MAX_DANCERS, COLLAB_PATH, A3Dancer)
    self.renda     = RendaController.new(COLLAB_PATH, 0)
    self.chibi     = ChibiController.new(bpm, COLLAB_PATH, 0)
    self.is_clear   = false
    self.is_rainbow = false
    self.last_milestone = 1
    self.needs_extra_dancers = true
    return self
end

function A3Background:update(current_ms, bpm)
    self.donbg:update(current_ms)
    self.bg_normal:update(current_ms)
    self.bg_fever:update(current_ms)
    self.dancer:update(current_ms, bpm)
    if self.needs_extra_dancers then
        self.needs_extra_dancers = false
        for _ = 1, 3 do self.dancer:add_dancer() end
    end
    self.renda:update(current_ms)
    self.chibi:update(current_ms, bpm)
end

function A3Background:handle_good(player_num)  self.chibi:add_chibi(player_num, false) end
function A3Background:handle_ok(player_num)    self.chibi:add_chibi(player_num, false) end
function A3Background:handle_bad(player_num)   self.chibi:add_chibi(player_num, true) end
function A3Background:handle_drumroll(player_num) self.renda:add_renda() end
function A3Background:handle_balloon(player_num)  self.renda:add_renda() end

function A3Background:handle_gauge(player_num, progress, is_clear, is_rainbow)
    self.donbg:set_clear(is_clear)
    if is_clear and not self.is_clear then self.bg_fever:start() end
    self.is_clear   = is_clear
    self.is_rainbow = is_rainbow

    local current_milestone
    if is_clear then
        current_milestone = MAX_DANCERS
    else
        current_milestone = math.min(MAX_DANCERS - 1, math.floor(progress * MAX_DANCERS))
    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

function A3Background:draw_back()
    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
    self.donbg:draw()
    self.renda:draw()
    self.dancer:draw()
    self.chibi:draw()
end

function A3Background:draw_fore() end

function A3Background:destroy()
    self.donbg:destroy()
    self.bg_normal:destroy()
    self.bg_fever:destroy()
    self.dancer:destroy()
    self.renda:destroy()
    self.chibi:destroy()
end

return A3Background