"use client";

import { useId } from "react";
import type { KeyboardEvent, ReactNode } from "react";
import { FRAME_TYPE_LABELS, PART_KIND_LABELS } from "@/lib/hive/labels";
import type { FrameBox, HiveLayout, PartBox, Vec3 } from "@/lib/hive/layout";
import type { FrameType } from "@/lib/hive/types";
import { useHiveView } from "./use-hive-view";

// SVG view of the hive: fallback without WebGL, print, and the L2 visual.
// Oblique projection of the shared layout (1 unit = 100 mm, y up). Strokes use
// currentColor so forced-colors and print follow the surrounding text colour.

const SKEW_X = 0.5;
const SKEW_Y = 0.35;
const PADDING = 0.05;
const FRAME_FILL_RATIO = 0.9;
const PATTERN_TILE = 0.16;
const EMPTY_VIEW_BOX = "0 0 1 1";

type Point = [number, number];

export function projectPoint([x, y, z]: Vec3): Point {
  return [x + SKEW_X * z, -(y - SKEW_Y * z)];
}

const fmt = (value: number): string => Number(value.toFixed(4)).toString();

function polygon(points: Vec3[]): string {
  return (
    points
      .map((point, index) => {
        const [x, y] = projectPoint(point);
        return `${index === 0 ? "M" : "L"}${fmt(x)} ${fmt(y)}`;
      })
      .join(" ") + " Z"
  );
}

function corners(box: { center: Vec3; size: Vec3 }): Vec3[] {
  const [cx, cy, cz] = box.center;
  const [w, h, d] = box.size;
  const result: Vec3[] = [];
  for (const dx of [-1, 1]) for (const dy of [-1, 1]) for (const dz of [-1, 1]) {
    result.push([cx + (dx * w) / 2, cy + (dy * h) / 2, cz + (dz * d) / 2]);
  }
  return result;
}

function viewBoxOf(layout: HiveLayout): string {
  const points = [...layout.parts, ...layout.inserts].flatMap((part) => corners(part).map(projectPoint));
  if (points.length === 0) return EMPTY_VIEW_BOX;
  const xs = points.map(([x]) => x);
  const ys = points.map(([, y]) => y);
  const minX = Math.min(...xs);
  const minY = Math.min(...ys);
  const width = Math.max(...xs) - minX;
  const height = Math.max(...ys) - minY;
  return [minX - PADDING * width, minY - PADDING * height, width * (1 + 2 * PADDING), height * (1 + 2 * PADDING)]
    .map(String)
    .join(" ");
}

/** "Beute mit 2 Zargen, Boden, Dach": boxes first, then the rest bottom to top. */
function summaryOf(layout: HiveLayout): string {
  if (layout.parts.length === 0) return "Beute ohne Teile";
  const counts = new Map<string, number>();
  for (const part of layout.parts) {
    const label = PART_KIND_LABELS[part.kind];
    counts.set(label, (counts.get(label) ?? 0) + 1);
  }
  const boxLabel = PART_KIND_LABELS.BOX;
  const labels = [...counts.keys()].sort((a, b) => Number(b === boxLabel) - Number(a === boxLabel));
  const items = labels.map((label) => {
    const count = counts.get(label) ?? 1;
    if (count === 1) return label;
    return label === boxLabel ? `${count} Zargen` : `${count}× ${label}`;
  });
  return `Beute mit ${items.join(", ")}`;
}

function framePitch(frame: FrameBox, all: FrameBox[]): number {
  const xs = all.filter((other) => other.boxId === frame.boxId).map((other) => other.center[0]).sort((a, b) => a - b);
  const gaps = xs.slice(1).map((x, index) => x - xs[index]);
  return gaps.length > 0 ? Math.min(...gaps) : frame.size[0];
}

// ---- Frame patterns: one per type, so the type never rides on colour alone ----

const T = PATTERN_TILE;
const PATTERNS: Record<Exclude<FrameType, "NONE">, ReactNode> = {
  BROOD: <circle cx={T / 2} cy={T / 2} r={0.035} className="fill-current stroke-none" />,
  DRONE: <circle cx={T / 2} cy={T / 2} r={0.06} className="fill-current stroke-none" />,
  HONEY: <path d={`M0 ${T} L${T} 0`} />,
  POLLEN: <path d={`M${T / 2} 0 V${T} M0 ${T / 2} H${T}`} />,
  FEED: <path d={`M0 ${T / 2} H${T}`} />,
  FOUNDATION: <path d={`M${T / 2} 0 V${T}`} />,
  EMPTY_COMB: <circle cx={T / 2} cy={T / 2} r={0.05} className="fill-none" />,
  DRONE_FRAME: <path d={`M0 0 L${T} ${T} M0 ${T} L${T} 0`} />,
  DIVIDER: <rect width={T} height={T} className="fill-current opacity-60 stroke-none" />,
};

const PATTERN_TYPES = Object.keys(PATTERNS) as Exclude<FrameType, "NONE">[];

// Colour comes from the <svg>; only hover changes it, never in print.
const HOVER_COLOR = "data-[hovered=true]:text-holo-edge-strong print:data-[hovered=true]:text-black";

const edge = "fill-none stroke-current [vector-effect:non-scaling-stroke]";

function activate(event: KeyboardEvent, action: () => void): void {
  if (event.key !== "Enter" && event.key !== " ") return;
  event.preventDefault();
  action();
}

export interface HiveSvgProps {
  layout: HiveLayout;
  onSelectPart?: (id: string) => void;
  onSelectFrame?: (boxId: string, slot: number) => void;
  /** Display name per part (see partDisplayName); defaults to the kind label. */
  partName?: (id: string) => string;
}

interface PartShapeProps {
  part: PartBox;
  dashed?: boolean;
  name: string;
  hovered: boolean;
  onSelect?: (id: string) => void;
  onHover: (id: string | null) => void;
}

function PartShape({ part, dashed, name, hovered, onSelect, onHover }: PartShapeProps) {
  const [cx, cy, cz] = part.center;
  const [w, h, d] = part.size;
  const [x0, x1, y0, y1, z0, z1] = [cx - w / 2, cx + w / 2, cy - h / 2, cy + h / 2, cz - d / 2, cz + d / 2];
  const faces = [
    polygon([[x0, y0, z0], [x1, y0, z0], [x1, y1, z0], [x0, y1, z0]]),
    polygon([[x0, y1, z0], [x1, y1, z0], [x1, y1, z1], [x0, y1, z1]]),
    polygon([[x1, y0, z0], [x1, y0, z1], [x1, y1, z1], [x1, y1, z0]]),
  ];
  const interactive = onSelect
    ? {
        role: "button" as const,
        tabIndex: -1,
        onClick: () => onSelect(part.id),
        onKeyDown: (event: KeyboardEvent) => activate(event, () => onSelect(part.id)),
        onPointerEnter: () => onHover(part.id),
        onPointerLeave: () => onHover(null),
      }
    : {};
  return (
    <g
      data-part-id={part.id}
      data-hovered={hovered ? "true" : undefined}
      className={`${HOVER_COLOR} ${onSelect ? "cursor-pointer" : ""}`}
      {...interactive}
    >
      <title>{name}</title>
      {faces.map((d_, index) => (
        <path
          key={index}
          d={d_}
          className={`${edge} fill-holo-fill ${dashed ? "[stroke-dasharray:4_3]" : ""}`}
          strokeWidth={hovered ? 2.5 : 1.5}
        />
      ))}
    </g>
  );
}

interface FrameShapeProps {
  frame: FrameBox;
  width: number;
  patternPrefix: string;
  hovered: boolean;
  onSelect?: (boxId: string, slot: number) => void;
  onHover: (frame: { boxId: string; slot: number } | null) => void;
}

function FrameShape({ frame, width, patternPrefix, hovered, onSelect, onHover }: FrameShapeProps) {
  const [cx, cy, cz] = frame.center;
  const [, h, d] = frame.size;
  const [x, y] = projectPoint([cx - width / 2, cy + h / 2, cz - d / 2]);
  const [x2, y2] = projectPoint([cx + width / 2, cy - h / 2, cz - d / 2]);
  const title = [`R${frame.slot}`, FRAME_TYPE_LABELS[frame.type], frame.name].filter(Boolean).join(" · ");
  const ref = { boxId: frame.boxId, slot: frame.slot };
  const interactive = onSelect
    ? {
        role: "button" as const,
        tabIndex: -1,
        onClick: () => onSelect(frame.boxId, frame.slot),
        onKeyDown: (event: KeyboardEvent) => activate(event, () => onSelect(frame.boxId, frame.slot)),
        onPointerEnter: () => onHover(ref),
        onPointerLeave: () => onHover(null),
      }
    : {};
  return (
    <g
      data-frame-box={frame.boxId}
      data-frame-slot={frame.slot}
      data-frame-type={frame.type}
      data-hovered={hovered ? "true" : undefined}
      className={`${HOVER_COLOR} ${onSelect ? "cursor-pointer" : ""}`}
      {...interactive}
    >
      <title>{title}</title>
      <rect
        x={x}
        y={y}
        width={x2 - x}
        height={y2 - y}
        fill={frame.type === "NONE" ? "none" : `url(#${patternPrefix}-${frame.type})`}
        className={`${edge} ${frame.type === "NONE" ? "[stroke-dasharray:2_3]" : ""}`}
        strokeWidth={hovered ? 2.5 : 1}
      />
    </g>
  );
}

export function HiveSvg({ layout, onSelectPart, onSelectFrame, partName }: HiveSvgProps) {
  const view = useHiveView();
  const patternPrefix = `hive${useId().replace(/[^a-zA-Z0-9]/g, "")}`;
  const nameOf = (part: PartBox): string => partName?.(part.id) ?? PART_KIND_LABELS[part.kind];
  const frames = view.openBoxId ? layout.frames.filter((frame) => frame.boxId === view.openBoxId) : [];
  const hoveredFrame = view.hoveredFrame;

  return (
    <svg
      role="img"
      aria-label={summaryOf(layout)}
      viewBox={viewBoxOf(layout)}
      preserveAspectRatio="xMidYMid meet"
      className="block h-full w-full bg-holo-bg text-holo-edge forced-colors:bg-[Canvas] forced-colors:text-[CanvasText] print:bg-transparent print:text-black"
    >
      {frames.length > 0 ? (
        <defs>
          {PATTERN_TYPES.map((type) => (
            <pattern
              key={type}
              id={`${patternPrefix}-${type}`}
              width={PATTERN_TILE}
              height={PATTERN_TILE}
              patternUnits="userSpaceOnUse"
              className="fill-none stroke-current"
              strokeWidth={0.02}
            >
              {PATTERNS[type]}
            </pattern>
          ))}
        </defs>
      ) : null}
      {layout.parts.map((part) => (
        <PartShape
          key={part.id}
          part={part}
          name={nameOf(part)}
          hovered={view.hoveredId === part.id}
          onSelect={onSelectPart}
          onHover={view.setHovered}
        />
      ))}
      {layout.inserts.map((insert) => (
        <PartShape
          key={insert.id}
          part={insert}
          dashed
          name={nameOf(insert)}
          hovered={view.hoveredId === insert.id}
          onSelect={onSelectPart}
          onHover={view.setHovered}
        />
      ))}
      {frames.map((frame) => (
        <FrameShape
          key={`${frame.boxId}-${frame.slot}`}
          frame={frame}
          width={framePitch(frame, frames) * FRAME_FILL_RATIO}
          patternPrefix={patternPrefix}
          hovered={hoveredFrame?.boxId === frame.boxId && hoveredFrame.slot === frame.slot}
          onSelect={onSelectFrame}
          onHover={view.setHoveredFrame}
        />
      ))}
    </svg>
  );
}