import type { Agent, ChatMessage } from './types';
import { msgId } from './types';

export class AgentChatState {
  messages = $state<ChatMessage[]>([]);
  conversationId: string;
  streaming = $state(false);
  streamingFrom = $state<string | null>(null);
  streamingText = $state<string | null>(null);
  streamingThinking = $state<string | null>(null);
  historyLoaded = $state(false);
  introRequested = $state(false);
  agentState = $state('unknown');
  scheduleVersion = $state(0);
  skillVersion = $state(0);

  constructor(agentId: string) {
    this.conversationId = `user:${agentId}`;
  }

  /** Merge server history into local messages without losing un-persisted local ones. */
  mergeHistory(serverMessages: ChatMessage[]): void {
    if (this.messages.length === 0) {
      this.messages = serverMessages;
      return;
    }

    const existingKeys = new Set(
      this.messages.map((m) => `${m.from}:${m.timestamp.getTime()}:${m.text.slice(0, 80)}`),
    );

    const merged: ChatMessage[] = [];
    for (const sm of serverMessages) {
      const key = `${sm.from}:${sm.timestamp.getTime()}:${sm.text.slice(0, 80)}`;
      if (!existingKeys.has(key)) {
        merged.push(sm);
      }
    }

    if (merged.length === 0) return;

    const combined = [...merged, ...this.messages];
    combined.sort((a, b) => a.timestamp.getTime() - b.timestamp.getTime());
    this.messages = combined;
  }
}

export type ConnectionState = 'connecting' | 'connected' | 'disconnected';

class AppState {
  agents = $state<Agent[]>([]);
  activeId = $state<string | null>(sessionStorage.getItem('mozartActiveAgent'));
  chats = $state<Record<string, AgentChatState>>({});
  connectionState = $state<ConnectionState>('connecting');

  get active(): Agent | undefined {
    return this.agents.find((a) => a.id === this.activeId);
  }

  ensureChat(id: string): AgentChatState {
    if (!this.chats[id]) {
      this.chats[id] = new AgentChatState(id);
    }
    return this.chats[id];
  }

  getChat(id: string): AgentChatState | undefined {
    return this.chats[id];
  }

  selectAgent(id: string) {
    this.ensureChat(id);
    this.activeId = id;
    sessionStorage.setItem('mozartActiveAgent', id);
  }

  removeChat(id: string) {
    delete this.chats[id];
    if (this.activeId === id) {
      this.activeId = null;
      sessionStorage.removeItem('mozartActiveAgent');
    }
  }
}

export const appState = new AppState();