import 'package:flutter/foundation.dart';

/// Role of a message inside a Copilot conversation.
enum CopilotRole { user, assistant }

/// A single reference image returned alongside an assistant answer
/// (e.g. a scanned page from a referenced document).
class CopilotImage {
  final String base64;
  final String source;
  final int page;
  final String? fileLink;
  final double? similarityScore;

  CopilotImage({
    required this.base64,
    required this.source,
    required this.page,
    this.fileLink,
    this.similarityScore,
  });

  factory CopilotImage.fromJson(Map<String, dynamic> json) => CopilotImage(
        base64: json['image_base64'] ?? '',
        source: json['source'] ?? '',
        page: json['page'] is int ? json['page'] : int.tryParse('${json['page']}') ?? 0,
        fileLink: json['file_link'],
        similarityScore: (json['similarity_score'] as num?)?.toDouble(),
      );
}

/// A single message (human query or assistant answer) inside a Copilot conversation.
///
/// This is intentionally a NEW, small model (not a reuse of chat's SingleUserChatModel),
/// since the Copilot Automation API response shape (answer/document_answer/website_answer/images)
/// is completely different from the multi-user chat history model.
class CopilotMessage {
  final String id;
  final CopilotRole role;
  String content; // assistant answer text OR the human query text
  String? documentAnswer;
  String? websiteAnswer;
  List<CopilotImage> images;
  DateTime? timestamp;
  bool isStreaming;
  bool isError;
  // Local path of a recorded audio file for a user's voice query (never a remote
  // download URL - the backend never sends audio back). Used to let the user
  // replay their own sent voice message, same as Chat's audio playback.
  String? localAudioPath;

  CopilotMessage({
    required this.id,
    required this.role,
    this.content = '',
    this.documentAnswer,
    this.websiteAnswer,
    this.images = const [],
    this.timestamp,
    this.isStreaming = false,
    this.isError = false,
    this.localAudioPath,
  });

  /// Builds a message from GetConversationByThreadId's flat message shape:
  /// { "role": "human"|"ai", "content": "...", "document_answer": "...", "website_answer": "...", "images": [...] }
  /// NOTE: the API currently always returns `timestamp: null`, so we fall back to
  /// "now" purely so the UI has a value to render (matches Chat's bubble layout,
  /// which always shows a time under each message).
  factory CopilotMessage.fromHistoryJson(Map<String, dynamic> json) => CopilotMessage(
        id: UniqueKey().toString(),
        role: json['role'] == 'ai' ? CopilotRole.assistant : CopilotRole.user,
        content: json['content'] ?? '',
        documentAnswer: json['document_answer'],
        websiteAnswer: json['website_answer'],
        images: (json['images'] as List? ?? []).map((e) => CopilotImage.fromJson(e)).toList(),
        timestamp: json['timestamp'] != null ? (DateTime.tryParse(json['timestamp'].toString()) ?? DateTime.now()) : DateTime.now(),
      );
}

/// A single event decoded from a QueryStream SSE `data:` line
/// (payload shape: {"type":"response","content":{...}}, or the literal string "[DONE]").
class CopilotStreamEvent {
  final String type;
  final CopilotStreamContent? content;

  CopilotStreamEvent({required this.type, this.content});

  factory CopilotStreamEvent.fromJson(Map<String, dynamic> json) => CopilotStreamEvent(
        type: json['type'] ?? '',
        content: json['content'] is Map<String, dynamic> ? CopilotStreamContent.fromJson(json['content']) : null,
      );
}

class CopilotStreamContent {
  final String? answer;
  final String? documentAnswer;
  final String? websiteAnswer;
  final int? chunksUsed;
  final List<CopilotImage> images;

  CopilotStreamContent({
    this.answer,
    this.documentAnswer,
    this.websiteAnswer,
    this.chunksUsed,
    this.images = const [],
  });

  factory CopilotStreamContent.fromJson(Map<String, dynamic> json) => CopilotStreamContent(
        answer: json['answer'],
        documentAnswer: json['document_answer'],
        websiteAnswer: json['website_answer'],
        chunksUsed: json['chunks_used'],
        images: (json['images'] as List? ?? []).map((e) => CopilotImage.fromJson(e)).toList(),
      );
}

/// A single row in the Copilot query history list (GetQueryHistory).
class CopilotHistoryItem {
  final String threadId;
  final String firstHumanMessage;
  final DateTime updatedAt;

  CopilotHistoryItem({
    required this.threadId,
    required this.firstHumanMessage,
    required this.updatedAt,
  });

  factory CopilotHistoryItem.fromJson(Map<String, dynamic> json) => CopilotHistoryItem(
        threadId: json['threadId'] ?? '',
        firstHumanMessage: json['firstHumanMessage'] ?? '',
        updatedAt: DateTime.tryParse(json['updatedAt'] ?? '') ?? DateTime.now(),
      );
}