local World = require("game.world")
local Palette = require("rendering.palette")

local Effects = {}

local CRACK_DURATION = 2.0
local CRACK_MIN_LINES = 8
local CRACK_MAX_LINES = 12

local crack = nil

local function buildCrack(cx, cy)
    local lines = {}
    local count = CRACK_MIN_LINES + math.floor(math.random() * (CRACK_MAX_LINES - CRACK_MIN_LINES + 1))
    local maxLen = math.max(World.screenW, World.screenH)
    for i = 1, count do
        local angle = (i / count) * math.pi * 2 + (math.random() - 0.5) * 0.4
        local len = maxLen * (0.6 + math.random() * 0.6)
        -- Jagged shards: a few jittered segments from the impact point outward
        local segments = {cx, cy}
        local steps = 3
        for s = 1, steps do
            local frac = s / steps
            local jitter = (math.random() - 0.5) * len * 0.12
            local perpAngle = angle + math.pi / 2
            local px = cx + math.cos(angle) * len * frac + math.cos(perpAngle) * jitter
            local py = cy + math.sin(angle) * len * frac + math.sin(perpAngle) * jitter
            table.insert(segments, px)
            table.insert(segments, py)
        end
        table.insert(lines, segments)
    end
    return { lines = lines, age = 0 }
end

function Effects.triggerCrack(cx, cy)
    cx = cx or World.screenW / 2
    cy = cy or (World.radarH + World.viewH / 2)
    crack = buildCrack(cx, cy)
end

function Effects.update(dt)
    if crack then
        crack.age = crack.age + dt
        if crack.age >= CRACK_DURATION then crack = nil end
    end
end

function Effects.draw()
    if not crack then return end
    local p = Palette.get()
    local fade = 1 - (crack.age / CRACK_DURATION)
    love.graphics.setColor(p.bright[1], p.bright[2], p.bright[3], fade)
    love.graphics.setLineWidth(2)
    for _, poly in ipairs(crack.lines) do
        love.graphics.line(poly)
    end
end

function Effects.clear()
    crack = nil
end

return Effects