import type { LayerSpecification, LightSpecification, SourceSpecification } from "maplibre-gl";
import { z } from "zod";
import { INTERACTIVE_HIT_LAYER_IDS } from "./layers";
import { MAP_STYLE_TOKENS as colors } from "./map-colors";

export const CITY_ROOT = "/city-model";
export const CITY_PREFIX = "fengxian-city-";
export const CITY_BUILDING_LAYER_ID = CITY_PREFIX + "buildings";
export const CITY_LIGHT = {
  anchor: "map",
  position: [1.5, 225, 35],
  color: "#EAF2F4",
  intensity: 0.42
} satisfies LightSpecification;

export function findCitySceneInsertionLayerId(layers: readonly LayerSpecification[]) {
  // Layers painted after a 3D extrusion bypass depth testing, so ground overlays stay below it.
  const hitLayerIds = new Set<string>(INTERACTIVE_HIT_LAYER_IDS);
  return layers.find((layer) => hitLayerIds.has(layer.id))?.id;
}

export const cityManifestSchema = z
  .object({
    schema_version: z.literal(1),
    name: z.string(),
    generated_at: z.string().datetime({ offset: true }).optional(),
    bbox: z.tuple([
      z.number().min(-180).max(180),
      z.number().min(-90).max(90),
      z.number().min(-180).max(180),
      z.number().min(-90).max(90)
    ]),
    building_count: z.number().int().nonnegative(),
    pipe_count: z.number().int().nonnegative(),
    asset_count: z.number().int().nonnegative(),
    notice: z.string(),
    attribution: z.string(),
    tiles: z
      .object({
        buildings: z.object({
          sha256: z
            .string()
            .regex(/^[a-f0-9]{64}$/)
            .optional()
        })
      })
      .optional()
  })
  .refine(({ bbox: [w, s, e, n] }) => w < e && s < n, "Invalid scene bounds");

export function cityBuildingArchiveUrl(origin = window.location.origin) {
  return new URL(`${CITY_ROOT}/buildings.pmtiles`, origin).href;
}

export function citySources(): Record<string, SourceSpecification> {
  return {
    [CITY_PREFIX + "buildings"]: {
      type: "vector",
      url: `pmtiles://${cityBuildingArchiveUrl()}`,
      minzoom: 12,
      maxzoom: 16,
      attribution:
        '© <a href="https://www.openstreetmap.org/copyright">OpenStreetMap contributors</a> · <a href="https://docs.overturemaps.org/attribution/">Overture Maps</a>',
      promoteId: "id"
    }
  };
}

export const CITY_LAYERS: LayerSpecification[] = [
  {
    id: CITY_BUILDING_LAYER_ID,
    source: CITY_PREFIX + "buildings",
    "source-layer": "buildings",
    type: "fill-extrusion",
    minzoom: 12,
    paint: {
      "fill-extrusion-color": colors.canvas.secondary,
      "fill-extrusion-height": ["to-number", ["get", "height_m"], 6],
      "fill-extrusion-base": 0,
      "fill-extrusion-opacity": 1,
      "fill-extrusion-vertical-gradient": true
    }
  }
];