package com.project.storage;

import com.project.model.PostInfo;

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.List;

public class DataStorage {
    
    public static void saveToCSV(List<PostInfo> posts, String directory) {
        if (posts == null || posts.isEmpty()) {
            System.out.println("没有数据需要保存");
            return;
        }
        
        try {
            java.nio.file.Path dirPath = Paths.get(directory);
            if (!Files.exists(dirPath)) {
                Files.createDirectories(dirPath);
            }
            
            String timestamp = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyyMMdd_HHmmss"));
            String filename = "posts_" + timestamp + ".csv";
            java.nio.file.Path filePath = dirPath.resolve(filename);
            
            try (BufferedWriter writer = new BufferedWriter(
                    new FileWriter(filePath.toFile(), StandardCharsets.UTF_8))) {
                
                writer.write("\uFEFF");
                writer.write("标题,内容,作者,发布日期,点赞数,评论数,浏览量,标签,情感倾向\n");
                
                for (PostInfo post : posts) {
                    writer.write(post.toCSV());
                    writer.write("\n");
                }
            }
            
            System.out.println("数据已保存到: " + filePath.toAbsolutePath());
            
        } catch (IOException e) {
            System.err.println("保存CSV文件时出错: " + e.getMessage());
        }
    }
    
    public static void saveToJSON(List<PostInfo> posts, String directory) {
        if (posts == null || posts.isEmpty()) {
            System.out.println("没有数据需要保存");
            return;
        }
        
        try {
            java.nio.file.Path dirPath = Paths.get(directory);
            if (!Files.exists(dirPath)) {
                Files.createDirectories(dirPath);
            }
            
            String timestamp = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyyMMdd_HHmmss"));
            String filename = "posts_" + timestamp + ".json";
            java.nio.file.Path filePath = dirPath.resolve(filename);
            
            try (BufferedWriter writer = new BufferedWriter(
                    new FileWriter(filePath.toFile(), StandardCharsets.UTF_8))) {
                
                writer.write("[\n");
                for (int i = 0; i < posts.size(); i++) {
                    writer.write(postToJSON(posts.get(i)));
                    if (i < posts.size() - 1) {
                        writer.write(",\n");
                    } else {
                        writer.write("\n");
                    }
                }
                writer.write("]\n");
            }
            
            System.out.println("数据已保存到: " + filePath.toAbsolutePath());
            
        } catch (IOException e) {
            System.err.println("保存JSON文件时出错: " + e.getMessage());
        }
    }
    
    private static String postToJSON(PostInfo post) {
        return String.format(
                "  {\n" +
                "    \"title\": \"%s\",\n" +
                "    \"content\": \"%s\",\n" +
                "    \"author\": \"%s\",\n" +
                "    \"postDate\": \"%s\",\n" +
                "    \"likeCount\": %d,\n" +
                "    \"commentCount\": %d,\n" +
                "    \"viewCount\": %d,\n" +
                "    \"tags\": \"%s\",\n" +
                "    \"sentiment\": \"%s\"\n" +
                "  }",
                escapeJSON(post.getTitle()),
                escapeJSON(post.getContent()),
                escapeJSON(post.getAuthor()),
                post.getPostDate() != null ? post.getPostDate().toString() : "",
                post.getLikeCount(),
                post.getCommentCount(),
                post.getViewCount(),
                escapeJSON(post.getTags()),
                escapeJSON(post.getSentiment())
        );
    }
    
    private static String escapeJSON(String text) {
        if (text == null) {
            return "";
        }
        return text.replace("\\", "\\\\")
                   .replace("\"", "\\\"")
                   .replace("\n", "\\n")
                   .replace("\r", "\\r")
                   .replace("\t", "\\t");
    }
}