/**
 * Liquid wave / מעבר נוזלי  (student motion library, id "tr-liquid")
 * Use: copy this file into your Remotion project and register it in your Root:
 *   <Composition id="LibTrLiquid" component={TrLiquid} width={1920} height={1080} fps={30}
 *     durationInFrames={60} defaultProps={liquidDefaults} />
 * Render transparent: npx remotion render src/index.ts LibTrLiquid out.webm --codec=vp9 --pixel-format=yuva420p --image-format=png --props=props.json
 * Change the words / colours / side in props.json (same keys as liquidDefaults). A vertical video: width 1080, height 1920.
 */
// ---------------------------------------------------------------- helpers (shared by every library scene)
// Conventions: 1920x1080, 30 fps, transparent background. Sizes follow the frame's short side, so 1080x1920 works too.
// Common props: duration (s), side 'right' | 'left' | 'center', x / y (centre in % of the frame, override side),
// scale, font (a CSS font-family; default Heebo). Time is in seconds; the first and last frames are empty.
import React from 'react';
import {AbsoluteFill, Easing, useCurrentFrame, useVideoConfig} from 'remotion';
import {loadFont as loadHeebo} from '@remotion/google-fonts/Heebo';


const heebo = loadHeebo('normal', {weights: ['400', '500', '700', '800', '900'], subsets: ['hebrew', 'latin']});
/** Hebrew + Latin font (Google "Heebo"). props.font overrides it per scene. */
export const HEEBO = `${heebo.fontFamily}, "Helvetica Neue", Arial, sans-serif`;
export const MONO = 'ui-monospace, "SF Mono", Menlo, Consolas, monospace';

export type Side = 'right' | 'left' | 'center';
export type Base = {duration?: number; side?: Side; x?: number; y?: number; scale?: number; font?: string};

export const clamp01 = (x: number) => Math.min(1, Math.max(0, x));
/** 0..1 progress of t between a and b (seconds) */
export const p01 = (t: number, a: number, b: number) => clamp01((t - a) / (b - a));
export const lerp = (a: number, b: number, k: number) => a + (b - a) * k;
export const outE = Easing.bezier(0.16, 1, 0.3, 1); // fast out, long settle
export const inOut = Easing.bezier(0.65, 0, 0.35, 1);
export const inE = Easing.bezier(0.55, 0, 0.9, 0.45);
export const backOut = (x: number, s = 1.7) => (x <= 0 ? 0 : x >= 1 ? 1 : 1 + (s + 1) * Math.pow(x - 1, 3) + s * Math.pow(x - 1, 2));
/** Damped spring 0 -> 1 starting at t0 (closed form, so any frame computes on its own). */
export const spr = (t: number, t0: number, freq = 16, damp = 9) => {
  const x = t - t0;
  return x <= 0 ? 0 : 1 - Math.exp(-damp * x) * Math.cos(freq * x);
};
/** Deterministic pseudo random 0..1 */
export const rnd = (i: number, seed = 1) => {
  const v = Math.sin(i * 127.1 + seed * 311.7) * 43758.5453;
  return v - Math.floor(v);
};
export const isHe = (s: string) => /[֐-׿]/.test(s);
export const dirOf = (s: string): 'rtl' | 'ltr' => (isHe(s) ? 'rtl' : 'ltr');
/** "#a1b2c3" / "#abc" + alpha -> rgba() */
export const rgba = (hex: string, a = 1) => {
  let h = hex.replace('#', '');
  if (h.length === 3) h = h.split('').map((ch) => ch + ch).join('');
  const n = parseInt(h.slice(0, 6), 16);
  return `rgba(${(n >> 16) & 255},${(n >> 8) & 255},${n & 255},${a})`;
};
export const useT = () => {
  const f = useCurrentFrame();
  const {fps} = useVideoConfig();
  return f / fps;
};
/** 12345 -> "12,345" */
export const fmt = (n: number, sep = ',') => Math.round(n).toString().replace(/\B(?=(\d{3})+(?!\d))/g, sep);

/** Arrive (scale up out of a blur) and leave (shrink into a blur) for a whole group. */
export const life = (t: number, total: number, inDur = 0.45, outDur = 0.35) => {
  const a = p01(t, 0, inDur);
  const z = inOut(p01(t, total - outDur, total));
  return {
    opacity: clamp01(a * 2.2) * (1 - z),
    scale: lerp(0.82, 1, backOut(a, 1.4)) * (1 - 0.08 * z),
    blur: (1 - outE(a)) * 12 + z * 10,
    style: {} as React.CSSProperties,
  };
};
export const lifeStyle = (t: number, total: number, inDur = 0.45, outDur = 0.35): React.CSSProperties => {
  const l = life(t, total, inDur, outDur);
  return {opacity: l.opacity, transform: `scale(${l.scale})`, filter: l.blur > 0.2 ? `blur(${l.blur}px)` : undefined};
};

/**
 * Places a w x h box (design pixels of a 1080-high frame) on its side of the frame and scales it with the frame's
 * short side and props.scale. Children are positioned inside the box.
 */
export const Stage: React.FC<{p: Base; w: number; h: number; children: React.ReactNode; style?: React.CSSProperties; defSide?: Side}> = ({p, w, h, children, style, defSide = 'center'}) => {
  const {width: W, height: H} = useVideoConfig();
  const u = (Math.min(W, H) / 1080) * (p.scale ?? 1);
  const side = p.side ?? defSide;
  const cx = ((p.x ?? (side === 'right' ? 73 : side === 'left' ? 27 : 50)) / 100) * W;
  const cy = ((p.y ?? 50) / 100) * H;
  return (
    <AbsoluteFill style={{pointerEvents: 'none'}}>
      <div style={{position: 'absolute', left: cx - w / 2, top: cy - h / 2, width: w, height: h, transform: `scale(${u})`, transformOrigin: '50% 50%', ...style}}>
        {children}
      </div>
    </AbsoluteFill>
  );
};

/** Soft two-layer drop shadow for cards on any footage */
export const SHADOW = '0 22px 48px rgba(12,12,20,0.22), 0 4px 12px rgba(12,12,20,0.14)';

/** The classic arrow cursor; (x, y) = its tip; press 0..1 = mouse down. */
export const Cursor: React.FC<{x: number; y: number; press?: number; size?: number; fill?: string; stroke?: string}> = ({x, y, press = 0, size = 1.6, fill = '#111', stroke = '#fff'}) => {
  const s = size * (1 - 0.12 * press);
  return (
    <svg viewBox="-2 -2 17 25" width={17 * s * 1.35} height={25 * s * 1.35} style={{position: 'absolute', left: x - 2.7 * s, top: y - 2.7 * s, overflow: 'visible', filter: 'drop-shadow(0 3px 4px rgba(0,0,0,0.35))'}}>
      <path d="M0 0 L0 17.4 L4 13.7 L6.9 20.4 L9.6 19.2 L6.8 12.8 L12.4 12.8 Z" fill={fill} stroke={stroke} strokeWidth={1.1} strokeLinejoin="round" />
    </svg>
  );
};

/** A four-point sparkle centred on (0,0) in a -50..50 box. */
export const SPARK_PATH = 'M0 -50 C 6 -14 14 -6 50 0 C 14 6 6 14 0 50 C -6 14 -14 6 -50 0 C -14 -6 -6 -14 0 -50 Z';
export const Spark: React.FC<{x: number; y: number; size: number; color: string; rotate?: number; opacity?: number; glow?: boolean}> = ({x, y, size, color, rotate = 0, opacity = 1, glow = false}) => (
  <svg viewBox="-50 -50 100 100" width={size} height={size} style={{position: 'absolute', left: x - size / 2, top: y - size / 2, transform: `rotate(${rotate}deg)`, opacity, overflow: 'visible', filter: glow ? `drop-shadow(0 0 ${size * 0.15}px ${color})` : undefined}}>
    <path d={SPARK_PATH} fill={color} />
  </svg>
);
// ---------------------------------------------------------------- the scene

/**
 * Liquid transition: a wavy liquid fills the frame from the bottom (a lighter wave runs just ahead of it, bubbles
 * rise inside), covers it at the middle (cut there), and drains away upwards, leaving the next shot. 2 s.
 * Inspired by "Liquid Transition Screen" (LottieFiles) and gooey blob loaders (CodePen), redesigned: two moving wave
 * fronts with bubbles, fill up and drain up.
 */
export type LiquidProps = Base & {
  color: string;
  front: string; // the lighter wave ahead of it
  waves: number;
};
export const liquidDefaults: LiquidProps = {
  duration: 2,
  color: '#3B5BFF',
  front: '#8FA2FF',
  waves: 2.5,
};

export const TrLiquid: React.FC<LiquidProps> = (props) => {
  const p = {...liquidDefaults, ...props};
  const t = useT();
  const {width: FW, height: FH} = useVideoConfig();
  const total = p.duration!;
  const mid = total / 2;
  const A = FH * 0.06; // wave height
  // level of the liquid surface (y of its top) and of its bottom edge when draining
  const up = inOut(p01(t, 0, mid));
  const drain = inOut(p01(t, mid, total));
  const wave = (y: number, k: number, ph: number): [number, number][] => {
    const N = 40;
    return Array.from({length: N + 1}, (_, i) => {
      const x = (i / N) * FW;
      return [x, y + Math.sin((i / N) * Math.PI * 2 * p.waves + t * 7 * k + ph) * A + Math.sin((i / N) * Math.PI * 2 * 1.3 - t * 4 + ph) * A * 0.4];
    });
  };
  // filling: the surface rises from below the frame to above it; then the bottom edge follows (it washes through)
  const lead = FH * 0.07;
  const M = A * 1.6 + lead; // past the frame edge, waves and the lighter band included
  const top = lerp(FH + M, -M, up);
  const bottom = lerp(FH + M, -M, drain);
  const shape = (topY: number, botY: number, ph: number) => {
    const a = wave(topY, 1, ph);
    const b = drain > 0 ? wave(botY, 1.2, ph + 1).reverse() : [[FW, FH + A * 3], [0, FH + A * 3]] as [number, number][];
    return [...a, ...b].map(([x, y], i) => `${i ? 'L' : 'M'}${x.toFixed(1)} ${y.toFixed(1)}`).join(' ') + ' Z';
  };
  return (
    <AbsoluteFill style={{overflow: 'hidden'}}>
      <svg width={FW} height={FH} style={{position: 'absolute', inset: 0}}>
        {up > 0 && drain < 1 && <path d={shape(top - lead, bottom + lead, 2)} fill={rgba(p.front, 0.95)} />}
        {up > 0 && drain < 1 && <path d={shape(top, bottom, 0)} fill={p.color} />}
        {Array.from({length: 14}, (_, i) => {
          const x = ((i * 0.137 + 0.05) % 1) * FW;
          const ph = (i * 0.29) % 1;
          const y = FH - ((t * 0.9 + ph) % 1) * FH * 1.2;
          const r = 6 + (i % 4) * 5;
          const inside = y > top + A * 1.5 && (drain === 0 || y < bottom - A * 1.5);
          return inside ? <circle key={i} cx={x} cy={y} r={r} fill={rgba('#ffffff', 0.22)} /> : null;
        })}
      </svg>
    </AbsoluteFill>
  );
};

export const meta = {id: 'LibTrLiquid', component: TrLiquid, defaults: liquidDefaults};