/**
 * Relay session manager
 * Tracks which relays are active/inactive during the current browser session
 * Relays that fail (connection or publish errors) are moved to the bottom of the priority list
 * All relays are reset to active on page load
 */

import { getEnabledRelays } from './config'

class RelaySessionManager {
  private failedRelays: Set<string> = new Set() // Relays that have failed (moved to bottom)

  /**
   * Initialize: reset all relays to active at session start
   */
  public async initialize(): Promise<void> {
    this.failedRelays.clear()
    console.log('[RelaySessionManager] Session initialized - all relays active')
  }

  /**
   * Get active relays (enabled relays, with failed ones moved to the bottom)
   * Failed relays are still active but prioritized last
   */
  public async getActiveRelays(): Promise<string[]> {
    const enabledRelays = await getEnabledRelays()

    // Separate working relays from failed ones
    const workingRelays: string[] = []
    const failedRelaysList: string[] = []

    for (const relay of enabledRelays) {
      if (this.failedRelays.has(relay)) {
        failedRelaysList.push(relay)
      } else {
        workingRelays.push(relay)
      }
    }

    // Return working relays first, then failed ones at the bottom
    return [...workingRelays, ...failedRelaysList]
  }

  /**
   * Mark a relay as failed (move it to the bottom of the priority list)
   */
  public markRelayFailed(relayUrl: string): void {
    if (!this.failedRelays.has(relayUrl)) {
      this.failedRelays.add(relayUrl)
      console.warn(`[RelaySessionManager] Relay moved to bottom of priority list: ${relayUrl}`)
    }
  }

  /**
   * Check if a relay has failed (is at the bottom of the list)
   */
  public isRelayFailed(relayUrl: string): boolean {
    return this.failedRelays.has(relayUrl)
  }

  /**
   * Get list of failed relays for this session
   */
  public getFailedRelays(): string[] {
    return Array.from(this.failedRelays)
  }

  /**
   * Get count of active relays (including failed ones at the bottom)
   */
  public async getActiveRelayCount(): Promise<number> {
    const activeRelays = await this.getActiveRelays()
    return activeRelays.length
  }

  /**
   * Legacy method name for compatibility (now moves to bottom instead of deactivating)
   */
  public markRelayInactive(relayUrl: string): void {
    this.markRelayFailed(relayUrl)
  }

  /**
   * Legacy method name for compatibility (failed relays are still "active" but at bottom)
   */
  public isRelayActive(_relayUrl: string): boolean {
    // All enabled relays are considered "active", even if failed
    // They're just at the bottom of the priority list
    return true
  }

  /**
   * Legacy method name for compatibility
   */
  public getInactiveRelays(): string[] {
    return this.getFailedRelays()
  }
}

export const relaySessionManager = new RelaySessionManager()

// Initialize on module load (page load)
if (typeof window !== 'undefined') {
  void relaySessionManager.initialize()
}