import {
	ForbiddenException,
	forwardRef,
	Inject,
	Injectable,
	NotFoundException,
} from "@nestjs/common";
import { ContentsRepository } from "../contents/repositories/contents.repository";
import { EventsGateway } from "../realtime/events.gateway";
import { S3Service } from "../s3/s3.service";
import type { CreateCommentDto } from "./dto/create-comment.dto";
import { CommentLikesRepository } from "./repositories/comment-likes.repository";
import { CommentsRepository } from "./repositories/comments.repository";

@Injectable()
export class CommentsService {
	constructor(
		private readonly commentsRepository: CommentsRepository,
		private readonly commentLikesRepository: CommentLikesRepository,
		@Inject(forwardRef(() => ContentsRepository))
		private readonly contentsRepository: ContentsRepository,
		private readonly s3Service: S3Service,
		private readonly eventsGateway: EventsGateway,
	) {}

	async create(userId: string, contentId: string, dto: CreateCommentDto) {
		const comment = await this.commentsRepository.create({
			userId,
			contentId,
			text: dto.text,
			parentId: dto.parentId,
		});

		// Récupérer le commentaire avec les infos utilisateur pour le WebSocket
		const enrichedComment = await this.findOneEnriched(comment.id, userId);
		if (!enrichedComment) return null;

		// Notifier les autres utilisateurs sur ce contenu (room de contenu)
		this.eventsGateway.sendToContent(contentId, "new_comment", enrichedComment);

		// Notifications ciblées
		try {
			// 1. Notifier l'auteur du post
			const content = await this.contentsRepository.findOne(contentId);
			if (content && content.userId !== userId) {
				this.eventsGateway.sendToUser(content.userId, "notification", {
					type: "comment",
					userId: userId,
					username: enrichedComment.user.username,
					contentId: contentId,
					commentId: comment.id,
					text: `a commenté votre post : "${dto.text.substring(0, 30)}${dto.text.length > 30 ? "..." : ""}"`,
				});
			}

			// 2. Si c'est une réponse, notifier l'auteur du commentaire parent
			if (dto.parentId) {
				const parentComment = await this.commentsRepository.findOne(dto.parentId);
				if (
					parentComment &&
					parentComment.userId !== userId &&
					(!content || parentComment.userId !== content.userId)
				) {
					this.eventsGateway.sendToUser(parentComment.userId, "notification", {
						type: "reply",
						userId: userId,
						username: enrichedComment.user.username,
						contentId: contentId,
						commentId: comment.id,
						text: `a répondu à votre commentaire : "${dto.text.substring(0, 30)}${dto.text.length > 30 ? "..." : ""}"`,
					});
				}
			}
		} catch (error) {
			console.error("Failed to send notification:", error);
		}

		return enrichedComment;
	}

	async findOneEnriched(commentId: string, currentUserId?: string) {
		const comment = await this.commentsRepository.findOneEnriched(commentId);
		if (!comment) return null;

		const [likesCount, isLiked] = await Promise.all([
			this.commentLikesRepository.countByCommentId(comment.id),
			currentUserId
				? this.commentLikesRepository.isLikedByUser(comment.id, currentUserId)
				: Promise.resolve(false),
		]);

		return {
			...comment,
			likesCount,
			isLiked,
			user: {
				...comment.user,
				avatarUrl: comment.user.avatarUrl
					? this.s3Service.getPublicUrl(comment.user.avatarUrl)
					: null,
			},
		};
	}

	async findAllByContentId(contentId: string, userId?: string) {
		const comments = await this.commentsRepository.findAllByContentId(contentId);

		return Promise.all(
			comments.map(async (comment) => {
				const [likesCount, isLiked] = await Promise.all([
					this.commentLikesRepository.countByCommentId(comment.id),
					userId
						? this.commentLikesRepository.isLikedByUser(comment.id, userId)
						: Promise.resolve(false),
				]);

				return {
					...comment,
					likesCount,
					isLiked,
					user: {
						...comment.user,
						avatarUrl: comment.user.avatarUrl
							? this.s3Service.getPublicUrl(comment.user.avatarUrl)
							: null,
					},
				};
			}),
		);
	}

	async remove(userId: string, commentId: string, isAdmin = false) {
		const comment = await this.commentsRepository.findOne(commentId);
		if (!comment) {
			throw new NotFoundException("Comment not found");
		}

		if (!isAdmin && comment.userId !== userId) {
			throw new ForbiddenException("You cannot delete this comment");
		}

		await this.commentsRepository.delete(commentId);
	}

	async like(userId: string, commentId: string) {
		const comment = await this.commentsRepository.findOne(commentId);
		if (!comment) {
			throw new NotFoundException("Comment not found");
		}
		await this.commentLikesRepository.addLike(commentId, userId);

		// Notifier l'auteur du commentaire
		if (comment.userId !== userId) {
			try {
				const liker = await this.findOneEnriched(commentId, userId);
				this.eventsGateway.sendToUser(comment.userId, "notification", {
					type: "like_comment",
					userId: userId,
					username: liker?.user.username,
					contentId: comment.contentId,
					commentId: commentId,
					text: "a aimé votre commentaire",
				});
			} catch (error) {
				console.error("Failed to send like notification:", error);
			}
		}
	}

	async unlike(userId: string, commentId: string) {
		const comment = await this.commentsRepository.findOne(commentId);
		if (!comment) {
			throw new NotFoundException("Comment not found");
		}
		await this.commentLikesRepository.removeLike(commentId, userId);
	}
}