using System.Reflection.Metadata;
using System.Text.RegularExpressions;
using DBConnection.Models;
using HtmlAgilityPack;

namespace WebNovelPortalAPI.Scrapers;

public class KakuyomuScraper : IScraper
{
    private const string UrlPattern = @"https?:\/\/kakuyomu\.jp\/works\/\d+\/?";
    private const string BaseUrl = "https://kakuyomu.jp";
    public bool MatchesUrl(string url)
    {
        var regex = new Regex(UrlPattern, RegexOptions.IgnoreCase);
        return regex.IsMatch(url);
    }

    private string GetNovelTitle(HtmlDocument document)
    {
        var xpath = @"//*[@id='workTitle']/a";
        return document.DocumentNode.SelectSingleNode(xpath).InnerText;
    }

    private Author GetAuthor(HtmlDocument document)
    {
        var nameXPath = @"//*[@id='workAuthor-activityName']/a";
        var urlXPath = @"//*[@id='workAuthor-activityName']/a";
        var authorName = document.DocumentNode.SelectSingleNode(nameXPath).InnerText;
        var authorUrl = document.DocumentNode.SelectSingleNode(urlXPath).Attributes["href"].Value;
        Author author = new Author
        {
            Name = authorName,
            Url = $"{BaseUrl + authorUrl}"
        };
        return author;

    }

    private List<Chapter> GetChapters(HtmlDocument document)
    {
        var urlxpath = @"//a[@class='widget-toc-episode-episodeTitle']";
        var namexpath = @"span";
        var urlnodes = document.DocumentNode.SelectNodes(urlxpath);
        var chapters = urlnodes.Select((node, i) => new Chapter
        {
            ChapterNumber = i + 1,
            Url = $"{BaseUrl}{node.Attributes["href"].Value}",
            Name = node.SelectSingleNode(namexpath).InnerText
        });

        return chapters.ToList();
    }

    private List<Tag> GetTags(HtmlDocument document)
    {
        var xpath = @"//span[@itemprop='keywords']/a";
        var nodes = document.DocumentNode.SelectNodes(xpath);
        return nodes.Select(node => new Tag
        {
            TagValue = node.InnerText
        }).ToList();
    }

    private DateTime GetPostedDate(HtmlDocument document)
    {
        var xpath = @"//time[@itemprop='datePublished']";
        return DateTime.Parse(document.DocumentNode.SelectSingleNode(xpath).InnerText);
    }

    private DateTime GetLastUpdatedDate(HtmlDocument document)
    {
        var xpath = @"//time[@itemprop='dateModified']";
        return DateTime.Parse(document.DocumentNode.SelectSingleNode(xpath).InnerText);
    }

    public Novel ScrapeNovel(string url)
    {
        Novel novel = new Novel();
        var web = new HtmlWeb();
        var doc = web.Load(url);
        if (doc == null)
        {
            throw new Exception("Error parsing document");
        }

        return new Novel
        {
            Author = GetAuthor(doc),
            Chapters = GetChapters(doc),
            DatePosted = GetPostedDate(doc),
            LastUpdated = GetLastUpdatedDate(doc),
            Tags = GetTags(doc),
            Title = GetNovelTitle(doc),
            Url = url
        };
    }

    public string? ScrapeChapterContent(string chapterUrl)
    {
        throw new NotImplementedException();
    }
}