import maplibregl from "maplibre-gl";
import React from "react";
import { createRoot } from "react-dom/client";

import TemplateMarkerCard from "./TemplateMarkerCard";
import { getDefaultTemplateCached } from "../../api/templates";

export function clearAllMarkers(markersRef, expandedElRef) {
  if (markersRef.current) {
    for (const m of markersRef.current) {
      try {
        if (m?.el && m.el.__reactRoot) {
          try { m.el.__reactRoot.unmount(); } catch {}
          m.el.__reactRoot = null;
        }
        m.marker.remove();
      } catch {}
    }
  }
  markersRef.current = [];
  if (expandedElRef) expandedElRef.current = null;
}

function rectsOverlap(a, b) {
  return !(a.right < b.left || a.left > b.right || a.bottom < b.top || a.top > b.bottom);
}

export function applyOcclusionForExpanded(markersRef, expandedEl) {
  if (!expandedEl) return;

  const expandedCard = expandedEl.querySelector(".post-card");
  if (!expandedCard) return;

  const PAD_X = 26;
  const PAD_TOP = 20;
  const PAD_BOTTOM = 140;

  const raw = expandedCard.getBoundingClientRect();
  const expandedRect = {
    left: raw.left - PAD_X,
    right: raw.right + PAD_X,
    top: raw.top - PAD_TOP,
    bottom: raw.bottom + PAD_BOTTOM,
  };

  const list = markersRef.current || [];
  for (const item of list) {
    const el = item?.el;
    if (!el || el === expandedEl) continue;

    const r = el.getBoundingClientRect();
    const isBelow = r.top >= raw.top;
    if (!isBelow) {
      el.style.visibility = "visible";
      el.style.pointerEvents = "auto";
      continue;
    }

    const hide = rectsOverlap(expandedRect, r);
    el.style.visibility = hide ? "hidden" : "visible";
    el.style.pointerEvents = hide ? "none" : "auto";
  }
}

export function clearOcclusion(markersRef) {
  const list = markersRef.current || [];
  for (const item of list) {
    const el = item?.el;
    if (!el) continue;
    el.style.visibility = "visible";
    el.style.pointerEvents = "auto";
  }
}

function escapeHtml(str) {
  return String(str)
    .replace(/&/g, "&amp;")
    .replace(/</g, "&lt;")
    .replace(/>/g, "&gt;")
    .replace(/"/g, "&quot;");
}

function currentTheme() {
  try {
    const t = document?.body?.getAttribute("data-theme") || "dark";
    if (t === "dark" || t === "blue" || t === "light") return t;
  } catch {}
  return "dark";
}

function ensureReactRoot(el) {
  if (el.__reactRoot) return el.__reactRoot;
  el.__reactRoot = createRoot(el);
  return el.__reactRoot;
}

export function createMarkerForPost(post, mapRef, markersRef, expandedElRef) {
  const map = mapRef.current;
  if (!map) return;

  const lat =
    typeof post.lat === "number"
      ? post.lat
      : typeof post.latitude === "number"
      ? post.latitude
      : null;

  const lon =
    typeof post.lon === "number"
      ? post.lon
      : typeof post.lng === "number"
      ? post.lng
      : null;

  if (lat == null || lon == null) {
    console.warn("post sans coordonnée:", post);
    return;
  }

  const title = (post.title || "").trim() || "Untitled";

  const root = document.createElement("div");
  root.className = "post-pin post-pin--compact";
  root.style.zIndex = "1";

  function renderCompact() {
    root.className = "post-pin post-pin--compact";
    root.style.zIndex = "1";

    root.innerHTML = `
      <div class="post-pin-bubble">
        <div class="post-pin-dot"></div>
        <div class="post-pin-text">${escapeHtml(title)}</div>
      </div>
      <div class="post-pin-pointer-small"></div>
    `;

    if (root.__reactRoot) {
      try { root.__reactRoot.unmount(); } catch {}
      root.__reactRoot = null;
    }

    clearOcclusion(markersRef);
  }

  async function renderExpanded() {
    root.className = "post-pin post-pin--expanded";
    root.style.zIndex = "999999";

    root.innerHTML = `
      <div class="post-card">
        <div class="post-card-body" style="font-size:11px; opacity:.9;">Loading template…</div>
      </div>
      <div class="post-card-pointer"></div>
    `;

    const cardEl = root.querySelector(".post-card");
    if (!cardEl) return;

    const theme = currentTheme();

    try {
      const tpl = await getDefaultTemplateCached("news");

      const rr = ensureReactRoot(cardEl);
      rr.render(
        React.createElement(TemplateMarkerCard, {
          post,
          template: tpl,
          theme,
          mode: "full",
        })
      );
    } catch (e) {
      cardEl.innerHTML = `
        <div style="font-weight:800; font-size:13px; margin-bottom:4px;">${escapeHtml(title)}</div>
        <div style="font-size:11px; opacity:.9;">(template load failed)</div>
      `;
    }

    requestAnimationFrame(() => {
      applyOcclusionForExpanded(markersRef, root);
    });
  }

  renderCompact();
  root.__renderCompact = renderCompact;

  const marker = new maplibregl.Marker({ element: root, anchor: "bottom" })
    .setLngLat([lon, lat])
    .addTo(map);

  markersRef.current.push({ id: post.id, marker, el: root, post });

  root.addEventListener("click", (ev) => {
    ev.stopPropagation();

    if (expandedElRef.current && expandedElRef.current !== root) {
      if (expandedElRef.current.__renderCompact) expandedElRef.current.__renderCompact();
      expandedElRef.current = null;
    }

    const isExpanded = root.classList.contains("post-pin--expanded");
    if (isExpanded) {
      renderCompact();
      expandedElRef.current = null;
    } else {
      renderExpanded();
      expandedElRef.current = root;
    }
  });
}