// First-person spell moments. The board flourishes (fx.ts) already know
// which event hurls what across which cells; this recasts their output
// into world-space projectiles, impact bursts, whole-screen flashes, and
// camera shakes for the raycaster to draw. What happens ACROSS the room
// is watched; what happens to YOU is felt.

import { fxForEvents } from "../fx";
import { CELL } from "../fx-sprites/geom";
import type { GameEvent, GameView } from "@wizwar/engine";

export type FpFx =
  | { id: number; kind: "projectile"; art: string; from: { x: number; y: number }; to: { x: number; y: number }; t0: number; dur: number }
  | { id: number; kind: "impact"; art: string; at: { x: number; y: number }; t0: number; dur: number }
  | { id: number; kind: "flash"; color: string; peak: number; t0: number; dur: number }
  | { id: number; kind: "shake"; mag: number; t0: number; dur: number };

/** The paintable conjuration sprites: public/fx3d/<name>.png, square with
 * transparent ground, drawn as a billboard mid-air. A procedural glow
 * stands in wherever a file is missing. */
export const FX_ART = [
  "fireball", "bolt", "waterbolt", "spark",
  "burst", "splash", "hit", "shimmer", "shield",
] as const;

let nextId = 1;

const PROJECTILE_DUR: Record<string, number> = { fireball: 420, bolt: 260, waterbolt: 420, spark: 350 };
/** Board-effect kinds that land here as an impact billboard. */
const IMPACT_ART: Record<string, string> = {
  burst: "burst", splash: "splash", fireworks: "burst",
  hit: "hit", pow: "hit", claw: "hit",
  shimmer: "shimmer", "portal-cell": "shimmer", sparkle: "shimmer",
  soul: "shimmer", "chaos-swirl": "shimmer", whiff: "shimmer",
  shield: "shield", absorb: "shield",
};

/** Translate one step's events into first-person moments with start delays. */
export function fpFxForEvents(
  events: GameEvent[], view: GameView, povId: string,
): { fx: FpFx; delay: number }[] {
  const out: { fx: FpFx; delay: number }[] = [];
  for (const { fx, delay } of fxForEvents(events, view)) {
    if (fx.kind === "fireball" || fx.kind === "bolt" || fx.kind === "waterbolt" || fx.kind === "streak") {
      const art = fx.kind === "streak" ? "spark" : fx.kind;
      out.push({
        fx: {
          id: nextId++, kind: "projectile", art,
          from: { x: fx.a.x / CELL, y: fx.a.y / CELL },
          to: { x: fx.b.x / CELL, y: fx.b.y / CELL },
          t0: 0, dur: PROJECTILE_DUR[art]!,
        },
        delay,
      });
    } else if (fx.kind === "portal") {
      out.push({
        fx: { id: nextId++, kind: "impact", art: "shimmer", at: { x: fx.cell.x + 0.5, y: fx.cell.y + 0.5 }, t0: 0, dur: 550 },
        delay,
      });
    } else if ("at" in fx && IMPACT_ART[fx.kind]) {
      out.push({
        fx: { id: nextId++, kind: "impact", art: IMPACT_ART[fx.kind]!, at: { x: fx.at.x + 0.5, y: fx.at.y + 0.5 }, t0: 0, dur: 550 },
        delay,
      });
    }
  }
  // Blows that land on the point of view: give impacts a beat to arrive
  // when something visibly flew first.
  const povDelay = out.some((o) => o.fx.kind === "projectile") ? 380 : 0;
  for (const e of events) {
    if (e.type === "damaged" && e.player === povId) {
      out.push({ fx: { id: nextId++, kind: "flash", color: "#c03020", peak: 0.4, t0: 0, dur: 450 }, delay: povDelay });
      out.push({ fx: { id: nextId++, kind: "shake", mag: Math.min(0.09, 0.03 + 0.015 * e.amount), t0: 0, dur: 420 }, delay: povDelay });
    } else if (e.type === "lifeGained" && e.player === povId) {
      out.push({ fx: { id: nextId++, kind: "flash", color: "#2a9a50", peak: 0.22, t0: 0, dur: 500 }, delay: povDelay });
    } else if (e.type === "teleported" && e.player === povId) {
      out.push({ fx: { id: nextId++, kind: "flash", color: "#8050d0", peak: 0.35, t0: 0, dur: 400 }, delay: 0 });
    } else if (e.type === "moved" && e.via === "warp" && e.player === povId) {
      out.push({ fx: { id: nextId++, kind: "flash", color: "#8050d0", peak: 0.28, t0: 0, dur: 350 }, delay: 0 });
    } else if (
      (e.type === "knockedBack" || e.type === "shoved" || e.type === "washedBack" || e.type === "retreatedInHorror") &&
      e.player === povId
    ) {
      out.push({ fx: { id: nextId++, kind: "shake", mag: 0.05, t0: 0, dur: 350 }, delay: povDelay });
    }
  }
  return out;
}

/** Procedural stand-ins for the conjuration sprites: a soft glow in each
 * art's palette, replaced on screen the moment a painted file loads. */
const FX_COLORS: Record<string, [string, string]> = {
  fireball: ["#ffe27a", "#e0431a"],
  bolt: ["#ffffff", "#7ab0ff"],
  waterbolt: ["#cfefff", "#1c6ed0"],
  spark: ["#fff6d8", "#c0a040"],
  burst: ["#fff0a0", "#d05010"],
  splash: ["#e8f8ff", "#2080c0"],
  hit: ["#ffd0c0", "#c02020"],
  shimmer: ["#f0e0ff", "#7040c0"],
  shield: ["#ffffff", "#4060d0"],
};
const baked = new Map<string, HTMLCanvasElement>();
export function fxFallback(name: string): HTMLCanvasElement {
  let t = baked.get(name);
  if (!t) {
    t = document.createElement("canvas");
    t.width = 64;
    t.height = 64;
    const c = t.getContext("2d")!;
    const [core, rim] = FX_COLORS[name] ?? FX_COLORS.spark!;
    const g = c.createRadialGradient(32, 32, 2, 32, 32, 30);
    g.addColorStop(0, core);
    g.addColorStop(0.55, rim);
    g.addColorStop(1, "rgba(0,0,0,0)");
    c.fillStyle = g;
    c.fillRect(0, 0, 64, 64);
    baked.set(name, t);
  }
  return t;
}