local DonBG = require("background/bg_objects/donbg")
local DonBGBase = require("background/bg_objects/donbg/base")

local COLLAB_PATH = "background/collab/tutorial"

local TutorialDonBG = setmetatable({}, { __index = DonBGBase })
TutorialDonBG.__index = TutorialDonBG

function TutorialDonBG.new(index, player_num, path)
    local self = setmetatable({}, TutorialDonBG)
    local base = DonBGBase.new(index, player_num, path)
    for k, v in pairs(base) do
        self[k] = v
    end
    self.move = anim.move(6000, { total_distance = -self.bg_texture.width, loop = true })
    self.move:start()
    self.overlay_move = tex.get_animation(2, "background")
    self.overlay_texture = tex.get_texture_info(self.name, "overlay")
    self.footer_texture = tex.get_texture_info(self.name, "footer")
    self._id_overlay = tex.get_texture(COLLAB_PATH .. "/" .. self.name .. "/" .. "overlay") or 0
    self._id_footer  = tex.get_texture(COLLAB_PATH .. "/" .. self.name .. "/" .. "footer") or 0
    return self
end

function TutorialDonBG:update(current_time_ms)
    DonBGBase.update(self, current_time_ms)
    self.overlay_move:update(current_time_ms)
end

-- One Fuji (background frame 1), one cloud (overlay) and one set of dots (background frame 2) per
-- pattern tile, all scrolling with the pattern: the Fuji's foot behind the fans, the dots around
-- the clouds (they bob with them). The cloud's place in the tile is overlay's x in texture.json.
local FUJI_X, FUJI_Y = 39, 91
local CLOUD_Y = 32
local DOTS_X, DOTS_Y = 32, CLOUD_Y + 13
-- The fans repeat every 80 px: their strips are tiled (and scroll a whole tile per loop) every
-- 560 px, a multiple of that, so the copies line up.
local FAN_TILE = 560
local FLOOR_DY = 34

function TutorialDonBG:draw_textures(fade, y, frame)
    y = y + 40
    local tile = self.bg_texture.width
    local bob = self.overlay_move.attribute
    for i = 0, 4 do
        tex.draw_texture(self._id_bg, {
            frame = 0,
            fade = fade,
            x = (i * tile) + self.move.attribute,
            y = y
        })
    end
    for i = 0, 3 do
        local x = (i * tile) + self.move.attribute
        tex.draw_texture(self._id_bg, { frame = 1, fade = fade, x = x + FUJI_X, y = y + FUJI_Y })
        tex.draw_texture(self._id_overlay, { frame = frame, fade = fade, x = x, y = y + CLOUD_Y + bob })
        tex.draw_texture(self._id_bg, { frame = 2, fade = fade, x = x + DOTS_X, y = y + DOTS_Y + bob })
    end
    local fan_x = self.move.attribute * (FAN_TILE / tile)
    for i = 0, 4 do
        tex.draw_texture(self._id_footer, { frame = 0, fade = fade, x = (i * FAN_TILE) + fan_x, y = y + bob })
        tex.draw_texture(self._id_footer, { frame = 1, fade = fade, x = (i * FAN_TILE) + fan_x, y = (y + 30) + bob })
        -- a third row so the fans reach down to the lane
        tex.draw_texture(self._id_footer, { frame = 1, fade = fade, x = (i * FAN_TILE) + fan_x, y = (y + 60) + bob })
    end
end

TutorialBackground = {}
TutorialBackground.__index = TutorialBackground

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

    tex.load_folder(COLLAB_PATH, "bg_normal/bg_0")
    self.donbg = TutorialDonBG.new(1, player_num, COLLAB_PATH)
    self._id_bg_0 = tex.get_texture(COLLAB_PATH .. "/" .. "bg_0" .. "/" .. "background") or 0
    self.floor_texture = tex.get_texture_info("bg_0", "background")

    return self
end

function TutorialBackground:update(current_ms, bpm)
    self.donbg:update(current_ms, bpm)
end

function TutorialBackground:handle_good(player_num) end

function TutorialBackground:handle_ok(player_num) end

function TutorialBackground:handle_bad(player_num) end

function TutorialBackground:handle_drumroll(player_num) end

function TutorialBackground:handle_balloon(player_num) end

function TutorialBackground:handle_gauge(player_num, progress, is_clear, is_rainbow) end

function TutorialBackground:draw_back()
    self.donbg:draw()
    -- the floor sits FLOOR_DY lower than texture.json says, so the drums clear the lane; the rows that
    -- would then run into the bottom band are cut off
    tex.draw_texture(self._id_bg_0, {
        y = FLOOR_DY, y2 = -FLOOR_DY,
        src = { x = 0, y = 0, width = self.floor_texture.width, height = self.floor_texture.height - FLOOR_DY },
    })
end

function TutorialBackground:draw_fore() end

function TutorialBackground:destroy()
    self.donbg:destroy()
    tex.unload_folder(COLLAB_PATH, "bg_normal/bg_0")
end

return TutorialBackground