import { and, eq, like, or, sql } from "drizzle-orm";
import { db } from "@mcpedia/db";
import { documents, type DocumentRow } from "@mcpedia/db/schema";
import { CONTENT_ROOT } from "@mcpedia/config";
import { parseFile } from "@mcpedia/parser";
import { existsSync } from "node:fs";
import { join } from "node:path";
import type {
  Document,
  ExportData,
  ExportQueryOptions,
} from "@mcpedia/types";
import { toMeta } from "./row-map";
import {
  buildExportSummary,
  sortExportDocuments,
} from "./export.helpers";

export * from "./export.helpers";
export * from "./export.docx";

/**
 * Fetch all documents for export with full bodies directly from PostgreSQL
 * (with fallback to disk if empty).
 */
export async function getExportDocuments(
  opts: ExportQueryOptions = {},
): Promise<ExportData> {
  const status = opts.status ?? "published";
  const sortBy = opts.sortBy ?? "category_points";

  let rows: DocumentRow[] = [];

  if (opts.slugs && opts.slugs.length > 0) {
    // Explicit list of slugs
    rows = await db
      .select()
      .from(documents)
      .where(
        and(
          eq(documents.status, status),
          sql`${documents.slug} IN ${opts.slugs}`,
        ),
      );
  } else if (opts.path) {
    const cleanPath = opts.path.replace(/^\/+|\/+$/g, "");

    // 1. Try exact match for single document
    const exactMatch = await db
      .select()
      .from(documents)
      .where(and(eq(documents.status, status), eq(documents.slug, cleanPath)));

    if (exactMatch.length === 1 && exactMatch[0]) {
      rows = exactMatch;
    } else {
      // 2. Try prefix match for folder/event or section
      rows = await db
        .select()
        .from(documents)
        .where(
          and(
            eq(documents.status, status),
            or(
              eq(documents.slug, cleanPath),
              like(documents.slug, `${cleanPath}/%`),
              eq(documents.section, cleanPath),
            ),
          ),
        );
    }
  } else if (opts.section) {
    // Section-wide match
    rows = await db
      .select()
      .from(documents)
      .where(
        and(
          eq(documents.status, status),
          eq(documents.section, opts.section),
        ),
      );
  } else {
    // All published documents
    rows = await db
      .select()
      .from(documents)
      .where(eq(documents.status, status));
  }

  // Map rows to Document with bodies
  const loadedDocs: Document[] = rows.map((row) => {
    let body = row.body;
    if (!body) {
      const abs = join(CONTENT_ROOT, row.path);
      if (existsSync(abs)) {
        try {
          const parsed = parseFile(abs, row.path);
          body = parsed.body;
        } catch {
          body = "";
        }
      }
    }
    return { ...toMeta(row), body: body || "" };
  });

  // Filter out meta index documents (like _index or index) when exporting multiple docs
  let filteredDocs = loadedDocs;
  if (loadedDocs.length > 1) {
    const withoutIndex = loadedDocs.filter((d) => {
      const slug = d.slug.toLowerCase();
      return (
        !slug.endsWith("/_index") &&
        !slug.endsWith("/index") &&
        slug !== "_index" &&
        slug !== "index" &&
        d.type !== "writeup-index"
      );
    });
    if (withoutIndex.length > 0) {
      filteredDocs = withoutIndex;
    }
  }

  // Sort neatly
  const sortedDocs = sortExportDocuments(filteredDocs, sortBy);
  const summary = buildExportSummary(sortedDocs, opts.path, opts.section);

  return {
    summary,
    documents: sortedDocs,
  };
}