local anim8 = require "lib.utils.anim8"

--- @class SpriteBehavior : Behavior
--- @field animationTable table<string, table>
--- @field animationGrid table
--- @field manifest table
--- @field sheets table
--- @field state "idle"|"run"|"hurt"|"attack"
--- @field side 1|-1
local sprite = {}
sprite.__index = sprite
sprite.id = "sprite"
sprite.LEFT = -1
sprite.RIGHT = 1
--- Скорость между кадрами в анимации
sprite.ANIMATION_SPEED = 0.1

function sprite.new(spriteDir)
    local anim = setmetatable({}, sprite)
    anim.animationTable = {}
    anim.animationGrid = {}
    anim.manifest = spriteDir.manifest
    anim.sheets = spriteDir.sheets
    -- n: name; i: image
    for n, i in pairs(spriteDir.sheets) do
        local aGrid = anim8.newGrid(anim.manifest.width, anim.manifest.height, i:getWidth(), i:getHeight())
        local tiles = '1-' .. math.ceil(i:getWidth() / anim.manifest.width)
        anim.animationGrid[n] = aGrid(tiles, 1)
    end

    anim.state = "idle"
    anim.side = sprite.RIGHT
    anim:loop("idle")
    return anim
end

function sprite:update(dt)
    local anim = self.animationTable[self.state] or self.animationTable["idle"] or nil

    if not anim then return end
    anim:update(dt)
end

function sprite:draw()
    if not self.animationTable[self.state] or not self.sheets[self.state] then return end

    self.owner:try(Tree.behaviors.positioned,
        function(pos)
            local ppm = Tree.level.camera.pixelsPerMeter
            local position = pos.position + Vec3 { 0.5, 0.5 }

            Tree.level.render:enqueue(Tree.level.render.LAYERS.SPRITE, position.y, function()
                love.graphics.setColor(1, 1, 1)

                -- Собираем источники света для шейдера
                local lightIds = Tree.level.lightGrid:query(position, 5)
                local lightsData = {}
                local numLights = 0
                for _, id in ipairs(lightIds) do
                    local light = Tree.level.characters[id]
                    local lPos = light:has(Tree.behaviors.positioned).position
                    local lColor = light:has(Tree.behaviors.light).color
                    table.insert(lightsData, { lPos.x, lPos.y, lColor.x, lColor.y, lColor.z })
                    numLights = numLights + 1
                    if numLights >= 8 then break end
                end

                local lightShader = Tree.assets.files.shaders.sprite_light
                local weather = Tree.level.weather
                lightShader:send("sprite_pos", { position.x, position.y })
                lightShader:send("sky", { weather.skyLight.x, weather.skyLight.y, weather.skyLight.z })
                lightShader:send("ambient", { weather.ambientLight.x, weather.ambientLight.y, weather.ambientLight.z })
                lightShader:send("num_lights", numLights)
                if numLights > 0 then
                    -- Формируем массив для шейдера: lights[i].position и lights[i].color
                    for i, data in ipairs(lightsData) do
                        lightShader:send(string.format("lights[%d].position", i - 1), { data[1], data[2] })
                        lightShader:send(string.format("lights[%d].color", i - 1), { data[3], data[4], data[5] })
                    end
                end

                love.graphics.setShader(lightShader)

                if Tree.level.selector.id == self.owner.id then
                    -- Если выбран, то рисуем еще и обводку?
                    -- В LÖVE нельзя поставить два шейдера сразу через setShader.
                    -- Для простоты пока оставим только свет, либо нужно комбинировать шейдеры.
                end

                self.animationTable[self.state]:draw(self.sheets[self.state],
                    position.x,
                    position.y, nil, 1 / ppm * self.side, 1 / ppm, self.manifest.base.x, self.manifest.base.y)

                love.graphics.setShader()
            end)
        end
    )
end

--- @return Task<nil>
function sprite:animate(state)
    return function(callback)
        if not self.animationGrid[state] then
            print("[SpriteBehavior]: no animation for '" .. state .. "'")
            return callback()
        end
        self.animationTable[state] = anim8.newAnimation(self.animationGrid[state], self.ANIMATION_SPEED,
            function()
                self:loop("idle")
                callback()
            end)
        self.state = state
    end
end

function sprite:loop(state)
    if not self.animationGrid[state] then
        return print("[SpriteBehavior]: no animation for '" .. state .. "'")
    end
    self.animationTable[state] = anim8.newAnimation(self.animationGrid[state], self.ANIMATION_SPEED)
    if state == 'idle' then
        self.animationTable[state]:gotoFrame(love.math.random(#self.animationTable[state].frames))
    end
    self.state = state
end

return sprite