import { ndkInstance } from "../ndk.ts";
import { fetchEventWithFallback, NDKRelaySetFromNDK } from "./nostrUtils.ts";
import { nip19 } from "nostr-tools";
import { NDKEvent } from "@nostr-dev-kit/ndk";
import type { Filter } from "./search_types.ts";
import { get } from "svelte/store";
import { wellKnownUrl, isValidNip05Address } from "./search_utils.ts";
import { TIMEOUTS, VALIDATION } from "./search_constants.ts";
import { activeInboxRelays, activeOutboxRelays } from "../ndk.ts";

/**
 * Search for a single event by ID or filter
 */
export async function searchEvent(query: string): Promise<NDKEvent | null> {
  const ndk = get(ndkInstance);
  if (!ndk) {
    console.warn("[Search] No NDK instance available");
    return null;
  }

  // AI-NOTE: 2025-01-24 - Wait for any relays to be available, not just pool relays
  // This ensures searches can proceed even if some relay types are not available
  let attempts = 0;
  const maxAttempts = 5; // Reduced since we'll use fallback relays
  
  while (attempts < maxAttempts) {
    // Check if we have any relays in the pool
    if (ndk.pool.relays.size > 0) {
      console.log(`[Search] Found ${ndk.pool.relays.size} relays in NDK pool`);
      break;
    }
    
    // Also check if we have any active relays
    const inboxRelays = get(activeInboxRelays);
    const outboxRelays = get(activeOutboxRelays);
    if (inboxRelays.length > 0 || outboxRelays.length > 0) {
      console.log(`[Search] Found active relays - inbox: ${inboxRelays.length}, outbox: ${outboxRelays.length}`);
      break;
    }
    
    console.log(`[Search] Waiting for relays to be available (attempt ${attempts + 1}/${maxAttempts})`);
    await new Promise(resolve => setTimeout(resolve, 500));
    attempts++;
  }

  // AI-NOTE: 2025-01-24 - Don't fail if no relays are available, let fetchEventWithFallback handle fallbacks
  // The fetchEventWithFallback function will use all available relays including fallback relays
  if (ndk.pool.relays.size === 0) {
    console.warn("[Search] No relays in pool, but proceeding with search - fallback relays will be used");
  }

  // Clean the query and normalize to lowercase
  const cleanedQuery = query.replace(/^nostr:/, "").toLowerCase();
  let filterOrId: Filter | string = cleanedQuery;

  // If it's a valid hex string, try as event id first, then as pubkey (profile)
  if (
    new RegExp(`^[a-f0-9]{${VALIDATION.HEX_LENGTH}}$`, "i").test(cleanedQuery)
  ) {
    // Try as event id
    filterOrId = cleanedQuery;
    const eventResult = await fetchEventWithFallback(
      get(ndkInstance),
      filterOrId,
      TIMEOUTS.EVENT_FETCH,
    );
    // Always try as pubkey (profile event) as well
    const profileFilter = { kinds: [0], authors: [cleanedQuery] };
    const profileEvent = await fetchEventWithFallback(
      get(ndkInstance),
      profileFilter,
      TIMEOUTS.EVENT_FETCH,
    );
    // Prefer profile if found and pubkey matches query
    if (
      profileEvent &&
      profileEvent.pubkey.toLowerCase() === cleanedQuery.toLowerCase()
    ) {
      return profileEvent;
    } else if (eventResult) {
      return eventResult;
    }
  } else if (
    new RegExp(
      `^(nevent|note|naddr|npub|nprofile)[a-z0-9]{${VALIDATION.MIN_NOSTR_IDENTIFIER_LENGTH},}$`,
      "i",
    ).test(cleanedQuery)
  ) {
    try {
      const decoded = nip19.decode(cleanedQuery);
      if (!decoded) throw new Error("Invalid identifier");
      
      console.log(`[Search] Decoded identifier:`, {
        type: decoded.type,
        data: decoded.data,
        query: cleanedQuery
      });
      
      switch (decoded.type) {
        case "nevent":
          console.log(`[Search] Processing nevent:`, {
            id: decoded.data.id,
            kind: decoded.data.kind,
            relays: decoded.data.relays
          });
          
          // Use the relays from the nevent if available
          if (decoded.data.relays && decoded.data.relays.length > 0) {
            console.log(`[Search] Using relays from nevent:`, decoded.data.relays);
            
            // Try to fetch the event using the nevent's relays
            try {
              // Create a temporary relay set for this search
              const neventRelaySet = NDKRelaySetFromNDK.fromRelayUrls(decoded.data.relays, ndk);
              
              if (neventRelaySet.relays.size > 0) {
                console.log(`[Search] Created relay set with ${neventRelaySet.relays.size} relays from nevent`);
                
                // Try to fetch the event using the nevent's relays
                const event = await ndk
                  .fetchEvent({ ids: [decoded.data.id] }, undefined, neventRelaySet)
                  .withTimeout(TIMEOUTS.EVENT_FETCH);
                
                if (event) {
                  console.log(`[Search] Found event using nevent relays:`, event.id);
                  return event;
                } else {
                  console.log(`[Search] Event not found on nevent relays, trying default relays`);
                }
              }
            } catch (error) {
              console.warn(`[Search] Error fetching from nevent relays:`, error);
            }
          }
          
          filterOrId = decoded.data.id;
          break;
        case "note":
          filterOrId = decoded.data;
          break;
        case "naddr":
          filterOrId = {
            kinds: [decoded.data.kind],
            authors: [decoded.data.pubkey],
            "#d": [decoded.data.identifier],
          };
          break;
        case "nprofile":
          filterOrId = {
            kinds: [0],
            authors: [decoded.data.pubkey],
          };
          break;
        case "npub":
          filterOrId = {
            kinds: [0],
            authors: [decoded.data],
          };
          break;
        default:
          filterOrId = cleanedQuery;
      }
    } catch (e) {
      console.error("[Search] Invalid Nostr identifier:", cleanedQuery, e);
      throw new Error("Invalid Nostr identifier.");
    }
  }

  try {
    const event = await fetchEventWithFallback(
      get(ndkInstance),
      filterOrId,
      TIMEOUTS.EVENT_FETCH,
    );

    if (!event) {
      console.warn("[Search] Event not found for filterOrId:", filterOrId);
      return null;
    } else {
      return event;
    }
  } catch (err) {
    console.error("[Search] Error fetching event:", err, "Query:", query);
    throw new Error("Error fetching event. Please check the ID and try again.");
  }
}

/**
 * Search for NIP-05 address
 */
export async function searchNip05(
  nip05Address: string,
): Promise<NDKEvent | null> {
  // NIP-05 address pattern: user@domain
  if (!isValidNip05Address(nip05Address)) {
    throw new Error("Invalid NIP-05 address format. Expected: user@domain");
  }

  try {
    const [name, domain] = nip05Address.split("@");

    const res = await fetch(wellKnownUrl(domain, name));

    if (!res.ok) {
      throw new Error(`HTTP ${res.status}: ${res.statusText}`);
    }

    const data = await res.json();

    // Try exact match first
    let pubkey = data.names?.[name];

    // If not found, try case-insensitive search
    if (!pubkey && data.names) {
      const names = Object.keys(data.names);
      const matchingName = names.find(
        (n) => n.toLowerCase() === name.toLowerCase(),
      );
      if (matchingName) {
        pubkey = data.names[matchingName];
        console.log(
          `[searchNip05] Found case-insensitive match: ${name} -> ${matchingName}`,
        );
      }
    }

    if (pubkey) {
      const profileFilter = { kinds: [0], authors: [pubkey] };
      const profileEvent = await fetchEventWithFallback(
        get(ndkInstance),
        profileFilter,
        TIMEOUTS.EVENT_FETCH,
      );
      if (profileEvent) {
        return profileEvent;
      } else {
        throw new Error(
          `No profile found for ${name}@${domain} (pubkey: ${pubkey})`,
        );
      }
    } else {
      throw new Error(`NIP-05 address not found: ${name}@${domain}`);
    }
  } catch (e) {
    console.error(
      `[Search] Error resolving NIP-05 address ${nip05Address}:`,
      e,
    );
    const errorMessage = e instanceof Error ? e.message : String(e);
    throw new Error(`Error resolving NIP-05 address: ${errorMessage}`);
  }
}

/**
 * Find containing 30040 index events for a given content event
 * @param contentEvent The content event to find containers for (30041, 30818, etc.)
 * @returns Array of containing 30040 index events
 */
export async function findContainingIndexEvents(
  contentEvent: NDKEvent,
): Promise<NDKEvent[]> {
  // Support all content event kinds that can be contained in indexes
  const contentEventKinds = [30041, 30818, 30040, 30023];
  if (!contentEventKinds.includes(contentEvent.kind!)) {
    return [];
  }

  try {
    const ndk = get(ndkInstance);

    // Search for 30040 events that reference this content event
    // We need to search for events that have an 'a' tag or 'e' tag referencing this event
    const contentEventId = contentEvent.id;
    const contentEventAddress = contentEvent.tagAddress();

    // Search for index events that reference this content event
    const indexEvents = await ndk.fetchEvents(
      {
        kinds: [30040],
        "#a": [contentEventAddress],
      },
      {
        groupable: true,
        skipVerification: false,
        skipValidation: false,
      },
    );

    // Also search for events with 'e' tags (legacy format)
    const indexEventsWithETags = await ndk.fetchEvents(
      {
        kinds: [30040],
        "#e": [contentEventId],
      },
      {
        groupable: true,
        skipVerification: false,
        skipValidation: false,
      },
    );

    // Combine and deduplicate results
    const allIndexEvents = new Set([...indexEvents, ...indexEventsWithETags]);

    // Filter to only include valid index events
    const validIndexEvents = Array.from(allIndexEvents).filter((event) => {
      // Check if it's a valid index event (has title, d tag, and either a or e tags)
      const hasTitle = event.getMatchingTags("title").length > 0;
      const hasDTag = event.getMatchingTags("d").length > 0;
      const hasATags = event.getMatchingTags("a").length > 0;
      const hasETags = event.getMatchingTags("e").length > 0;

      return hasTitle && hasDTag && (hasATags || hasETags);
    });

    return validIndexEvents;
  } catch (error) {
    console.error("[Search] Error finding containing index events:", error);
    return [];
  }
}