/* Build a self-contained Markdown report from one stored CMap and its links. */
((root, factory) => {
  const api = factory();
  if (typeof module === "object" && module.exports) module.exports = api;
  if (root) root.RacketWikiCmapExport = api;
})(typeof window !== "undefined" ? window : globalThis, () => {
  "use strict";

  const labels = {
    en: {
      exportTitle: "CMap export", generated: "Generated", root: "Root CMap",
      depth: "Linked CMap depth", pagesIncluded: "Linked wiki pages included",
      yes: "yes", no: "no", cmap: "CMap", level: "level", address: "Address",
      tags: "Tags", none: "none", summary: "Summary", noSummary: "No summary supplied.",
      explanation: "CMap explanation", concepts: "Concepts", relations: "Relations",
      linkedMaps: "Linked CMaps", noConcepts: "No concepts.", noRelations: "No relations.",
      synopsis: "Summary", aspects: "Aspects", wikiPage: "Wiki page",
      conceptExplanation: "Concept explanation", linkedCmap: "Linked CMap", webPage: "Web page",
      people: "People (responsibility/action)",
      placements: "Placements", sourceView: "Derived view of", sourceMissing: "Source CMap unavailable",
      missingPage: "Page unavailable", linkedPages: "Linked wiki pages", page: "Page"
    },
    nl: {
      exportTitle: "CMap-export", generated: "Gegenereerd", root: "Start-CMap",
      depth: "Diepte gekoppelde CMaps", pagesIncluded: "Gekoppelde wikipagina's opgenomen",
      yes: "ja", no: "nee", cmap: "CMap", level: "niveau", address: "Adres",
      tags: "Tags", none: "geen", summary: "Samenvatting", noSummary: "Geen samenvatting opgegeven.",
      explanation: "CMap-uitleg", concepts: "Concepten", relations: "Relaties",
      linkedMaps: "Gekoppelde CMaps", noConcepts: "Geen concepten.", noRelations: "Geen relaties.",
      synopsis: "Samenvatting", aspects: "Aspecten", wikiPage: "Wikipagina",
      conceptExplanation: "Conceptuitleg", linkedCmap: "Gekoppelde CMap", webPage: "Webpagina",
      people: "Personen (verantwoordelijkheid/actie)",
      placements: "Plaatsingen", sourceView: "Afgeleide weergave van", sourceMissing: "Bron-CMap niet beschikbaar",
      missingPage: "Pagina niet beschikbaar", linkedPages: "Gekoppelde wikipagina's", page: "Pagina"
    }
  };

  function decodedDocument(value) {
    let documentValue = value;
    for (let attempt = 0; attempt < 2 && typeof documentValue === "string"; attempt += 1) {
      documentValue = JSON.parse(documentValue);
    }
    return documentValue && typeof documentValue === "object" && !Array.isArray(documentValue) ?
      documentValue : {};
  }

  function cleanMetadata(documentValue) {
    const metadata = documentValue.metadata && typeof documentValue.metadata === "object" ?
      documentValue.metadata : {};
    return {
      tags: Array.isArray(metadata.tags) ? metadata.tags.map(String).map((tag) => tag.trim()).filter(Boolean) : [],
      summary: String(metadata.summary || "").trim(),
      explanationPageSlug: String(metadata.explanationPageSlug || "").trim()
    };
  }

  function itemRecords(documentValue) {
    const concepts = new Map((Array.isArray(documentValue.concepts) ? documentValue.concepts : [])
      .filter((concept) => concept && concept.id)
      .map((concept) => [String(concept.id), concept]));
    return (Array.isArray(documentValue.items) ? documentValue.items : [])
      .filter((item) => item && item.id !== undefined)
      .map((item) => ({
        ...item,
        ...(concepts.get(String(item.conceptId)) || {}),
        id: item.id,
        conceptId: item.conceptId
      }));
  }

  function derivedDocument(sourceDocument, derivedDocumentValue) {
    const pointer = derivedDocumentValue.derivedView || {};
    const rootId = Number(pointer.rootItemId);
    const allItems = Array.isArray(sourceDocument.items) ? sourceDocument.items : [];
    const byId = new Map(allItems.map((item) => [Number(item.id), item]));
    const belongsToRoot = (item) => {
      if (Number(item.id) === rootId) return true;
      let parentId = Number(item.parentSubmapId);
      const seen = new Set();
      while (Number.isInteger(parentId) && parentId > 0 && !seen.has(parentId)) {
        if (parentId === rootId) return true;
        seen.add(parentId);
        parentId = Number(byId.get(parentId)?.parentSubmapId);
      }
      return false;
    };
    const items = allItems.filter(belongsToRoot);
    const itemIds = new Set(items.map((item) => Number(item.id)));
    const conceptIds = new Set(items.map((item) => item.conceptId).filter(Boolean).map(String));
    const rootItem = itemRecords(sourceDocument).find((item) => Number(item.id) === rootId) ||
      byId.get(rootId) || {};
    const ownMetadata = cleanMetadata(derivedDocumentValue);
    const metadata = {
      tags: ownMetadata.tags.length ? ownMetadata.tags :
        (Array.isArray(rootItem.aspects) ? rootItem.aspects.map(String) : []),
      summary: ownMetadata.summary || String(rootItem.synopsis || "").trim(),
      explanationPageSlug: ownMetadata.explanationPageSlug || String(rootItem.descriptionPageSlug || "").trim()
    };
    return {
      ...sourceDocument,
      metadata,
      items,
      concepts: (Array.isArray(sourceDocument.concepts) ? sourceDocument.concepts : [])
        .filter((concept) => conceptIds.has(String(concept.id))),
      connectors: (Array.isArray(sourceDocument.connectors) ? sourceDocument.connectors : [])
        .filter((connector) => itemIds.has(Number(connector.sourceId)) && itemIds.has(Number(connector.targetId)))
    };
  }

  async function resolveMapDocument(map, loadConceptMap) {
    const ownDocument = decodedDocument(map.document);
    const pointer = ownDocument.derivedView;
    if (!pointer || !pointer.sourceCmapSlug || !Number.isInteger(Number(pointer.rootItemId))) {
      return { document: ownDocument, sourceSlug: "" };
    }
    try {
      const sourceMap = await loadConceptMap(pointer.sourceCmapSlug);
      return {
        document: derivedDocument(decodedDocument(sourceMap.document), ownDocument),
        sourceSlug: pointer.sourceCmapSlug
      };
    } catch (_error) {
      return { document: ownDocument, sourceSlug: pointer.sourceCmapSlug, sourceMissing: true };
    }
  }

  function linkedMapSlugs(documentValue) {
    return [...new Set(itemRecords(documentValue)
      .map((item) => String(item.cmapSlug || "").trim())
      .filter(Boolean))];
  }

  function headingText(value) {
    return String(value || "").replace(/[\r\n]+/g, " ").replace(/#+/g, "").trim();
  }

  function inlineText(value) {
    return String(value || "").replace(/[\r\n]+/g, " ").replace(/([\\`*_[\]])/g, "\\$1").trim();
  }

  function shiftHeadings(markdown, amount) {
    let fenced = false;
    return String(markdown || "").split("\n").map((line) => {
      if (/^\s*(```|~~~)/.test(line)) {
        fenced = !fenced;
        return line;
      }
      if (fenced) return line;
      return line.replace(/^(#{1,6})\s+/, (match, hashes) =>
        `${"#".repeat(Math.min(6, hashes.length + amount))} `);
    }).join("\n");
  }

  function relationLines(documentValue) {
    const items = itemRecords(documentValue);
    const byId = new Map(items.map((item) => [Number(item.id), item]));
    const connectors = (Array.isArray(documentValue.connectors) ? documentValue.connectors : [])
      .filter((connector) => connector && connector.sourceId !== undefined && connector.targetId !== undefined);
    const used = new Set();
    const result = [];
    const itemLabel = (id) => headingText(byId.get(Number(id))?.label || `[${id}]`);

    for (const phrase of items.filter((item) => item.kind === "phrase")) {
      const incoming = connectors.filter((connector) => Number(connector.targetId) === Number(phrase.id));
      const outgoing = connectors.filter((connector) => Number(connector.sourceId) === Number(phrase.id));
      for (const before of incoming) {
        for (const after of outgoing) {
          used.add(before);
          used.add(after);
          result.push(`${itemLabel(before.sourceId)} — **${inlineText(phrase.label || "")}** → ${itemLabel(after.targetId)}`);
        }
      }
    }
    for (const connector of connectors) {
      if (used.has(connector)) continue;
      result.push(`${itemLabel(connector.sourceId)} ${connector.hasArrow === false ? "—" : "→"} ${itemLabel(connector.targetId)}`);
    }
    return result;
  }

  function conceptEntries(documentValue) {
    const entries = new Map();
    for (const item of itemRecords(documentValue)) {
      if (item.kind === "phrase") continue;
      const key = item.conceptId ? `concept:${item.conceptId}` : `item:${item.id}`;
      if (!entries.has(key)) entries.set(key, { ...item, placementCount: 0 });
      entries.get(key).placementCount += 1;
    }
    return [...entries.values()];
  }

  async function generateMarkdown(options) {
    const rootMap = options.rootMap;
    if (!rootMap || !rootMap.slug) throw new Error("A root CMap is required.");
    if (typeof options.loadConceptMap !== "function") throw new Error("loadConceptMap is required.");
    const maximumDepth = Math.max(0, Math.min(10, Number(options.maxDepth) || 0));
    const includeWikiPages = Boolean(options.includeWikiPages);
    const locale = String(options.language || "nl").toLowerCase().startsWith("nl") ? "nl" : "en";
    const t = labels[locale];
    const maps = [];
    const visited = new Set();

    async function collectMap(map, depth) {
      if (!map?.slug || visited.has(map.slug)) return;
      visited.add(map.slug);
      const resolved = await resolveMapDocument(map, options.loadConceptMap);
      maps.push({ map, depth, ...resolved });
      if (depth >= maximumDepth) return;
      for (const slug of linkedMapSlugs(resolved.document)) {
        if (visited.has(slug)) continue;
        try {
          await collectMap(await options.loadConceptMap(slug), depth + 1);
        } catch (error) {
          maps.push({ map: { slug, title: slug }, depth: depth + 1, document: {}, loadError: error });
          visited.add(slug);
        }
      }
    }
    await collectMap(rootMap, 0);

    const pageCache = new Map();
    const explanationReferences = new Set();
    async function loadPage(reference) {
      if (!reference || typeof options.loadWikiPage !== "function") return null;
      if (!pageCache.has(reference)) {
        pageCache.set(reference, Promise.resolve().then(() => options.loadWikiPage(reference))
          .catch((error) => ({ slug: reference, title: reference, loadError: error })));
      }
      return pageCache.get(reference);
    }

    for (const entry of maps) {
      const metadata = cleanMetadata(entry.document);
      if (metadata.explanationPageSlug) {
        explanationReferences.add(metadata.explanationPageSlug);
        await loadPage(metadata.explanationPageSlug);
      }
      if (includeWikiPages) {
        for (const concept of conceptEntries(entry.document)) {
          await loadPage(concept.pageSlug);
          await loadPage(concept.descriptionPageSlug);
        }
      }
    }

    const lines = [
      `# ${t.exportTitle}: ${headingText(rootMap.title || rootMap.slug)}`,
      "",
      `- **${t.generated}:** ${new Date().toISOString()}`,
      `- **${t.root}:** \`cmap:${rootMap.slug}\``,
      `- **${t.depth}:** ${maximumDepth}`,
      `- **${t.pagesIncluded}:** ${includeWikiPages ? t.yes : t.no}`,
      ""
    ];

    for (const entry of maps) {
      const metadata = cleanMetadata(entry.document);
      lines.push(`## ${t.cmap}: ${headingText(entry.map.title || entry.map.slug)} (${t.level} ${entry.depth})`, "");
      lines.push(`- **${t.address}:** \`cmap:${entry.map.slug}\``);
      lines.push(`- **${t.tags}:** ${metadata.tags.length ? metadata.tags.map((tag) => `\`${inlineText(tag)}\``).join(", ") : t.none}`);
      if (entry.sourceSlug) lines.push(`- **${t.sourceView}:** \`cmap:${entry.sourceSlug}\``);
      if (entry.sourceMissing) lines.push(`- **${t.sourceMissing}:** \`cmap:${entry.sourceSlug}\``);
      if (entry.loadError) lines.push(`- **Fout:** ${inlineText(entry.loadError.message || entry.loadError)}`);
      lines.push("", `### ${t.summary}`, "", metadata.summary || t.noSummary, "");

      if (metadata.explanationPageSlug) {
        const page = await loadPage(metadata.explanationPageSlug);
        lines.push(`### ${t.explanation}`, "", `**${t.page}:** \`${metadata.explanationPageSlug}\``, "");
        if (page?.loadError) lines.push(`_${t.missingPage}: ${inlineText(page.loadError.message || page.loadError)}_`, "");
        else if (page) {
          if (Array.isArray(page.tags) && page.tags.length) {
            lines.push(`**${t.tags}:** ${page.tags.map((tag) => `\`${inlineText(tag)}\``).join(", ")}`, "");
          }
          lines.push(shiftHeadings(page.markdown || "", 3).trim() || t.noSummary, "");
        }
      }

      lines.push(`### ${t.concepts}`, "");
      const concepts = conceptEntries(entry.document);
      if (!concepts.length) lines.push(`_${t.noConcepts}_`, "");
      for (const concept of concepts) {
        lines.push(`#### ${headingText(concept.label || concept.id || "Concept")}`, "");
        if (concept.synopsis) lines.push(`- **${t.synopsis}:** ${inlineText(concept.synopsis)}`);
        if (Array.isArray(concept.aspects) && concept.aspects.length) {
          lines.push(`- **${t.aspects}:** ${concept.aspects.map(inlineText).join(", ")}`);
        }
        const people = (Array.isArray(concept.tags) ? concept.tags : [])
          .filter((tag) => tag && typeof tag === "object" && tag.type === "person" && tag.value)
          .map((tag) => tag.value);
        if (people.length) {
          lines.push(`- **${t.people}:** ${people.map(inlineText).join(", ")}`);
        }
        if (concept.pageSlug) lines.push(`- **${t.wikiPage}:** \`${inlineText(concept.pageSlug)}\``);
        if (concept.descriptionPageSlug) lines.push(`- **${t.conceptExplanation}:** \`${inlineText(concept.descriptionPageSlug)}\``);
        if (concept.cmapSlug) lines.push(`- **${t.linkedCmap}:** \`cmap:${inlineText(concept.cmapSlug)}\``);
        if (concept.externalUrl) lines.push(`- **${t.webPage}:** ${inlineText(concept.externalUrl)}`);
        if (concept.placementCount > 1) lines.push(`- **${t.placements}:** ${concept.placementCount}`);
        lines.push("");
      }

      lines.push(`### ${t.relations}`, "");
      const relations = relationLines(entry.document);
      if (!relations.length) lines.push(`_${t.noRelations}_`, "");
      else lines.push(...relations.map((relation) => `- ${relation}`), "");
      const linked = linkedMapSlugs(entry.document);
      if (linked.length) {
        lines.push(`### ${t.linkedMaps}`, "", ...linked.map((slug) => `- \`cmap:${inlineText(slug)}\``), "");
      }
    }

    if (includeWikiPages) {
      const pages = [];
      for (const [reference, promise] of pageCache) {
        if (explanationReferences.has(reference)) continue;
        pages.push(await promise);
      }
      if (pages.length) lines.push(`## ${t.linkedPages}`, "");
      for (const page of pages) {
        lines.push(`### ${headingText(page.title || page.slug)}`, "", `- **${t.address}:** \`${inlineText(page.slug)}\``);
        if (Array.isArray(page.tags) && page.tags.length) {
          lines.push(`- **${t.tags}:** ${page.tags.map((tag) => `\`${inlineText(tag)}\``).join(", ")}`);
        }
        lines.push("");
        if (page.loadError) lines.push(`_${t.missingPage}: ${inlineText(page.loadError.message || page.loadError)}_`, "");
        else lines.push(shiftHeadings(page.markdown || "", 2).trim() || t.noSummary, "");
      }
    }

    return `${lines.join("\n").replace(/\n{3,}/g, "\n\n").trim()}\n`;
  }

  return { generateMarkdown, decodedDocument, derivedDocument, relationLines };
});