using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using OF_DL.Enumurations;
using System.IO;
using Microsoft.Data.Sqlite;
using Serilog;
using OF_DL.Entities;

namespace OF_DL.Helpers
{
    public class DBHelper : IDBHelper
    {
        private readonly IDownloadConfig downloadConfig;

        public DBHelper(IDownloadConfig downloadConfig)
        {
            this.downloadConfig = downloadConfig;
        }

        public async Task CreateDB(string folder)
        {
            try
            {
                if (!Directory.Exists(folder + "/Metadata"))
                {
                    Directory.CreateDirectory(folder + "/Metadata");
                }

                string dbFilePath = $"{folder}/Metadata/user_data.db";

                // connect to the new database file
                using SqliteConnection connection = new($"Data Source={dbFilePath}");
                // open the connection
                connection.Open();

                // create the 'medias' table
                using (SqliteCommand cmd = new("CREATE TABLE IF NOT EXISTS medias (id INTEGER NOT NULL, media_id INTEGER, post_id INTEGER NOT NULL, link VARCHAR, directory VARCHAR, filename VARCHAR, size INTEGER, api_type VARCHAR, media_type VARCHAR, preview INTEGER, linked VARCHAR, downloaded INTEGER, created_at TIMESTAMP, record_created_at TIMESTAMP, PRIMARY KEY(id), UNIQUE(media_id));", connection))
                {
                    await cmd.ExecuteNonQueryAsync();
                }

                await EnsureCreatedAtColumnExists(connection, "medias");

                //
                // Alter existing databases to create unique constraint on `medias`
                //
                using (SqliteCommand cmd = new(@"
                    PRAGMA foreign_keys=off;

                    BEGIN TRANSACTION;

                    ALTER TABLE medias RENAME TO old_medias;

                    CREATE TABLE medias (
                        id INTEGER NOT NULL,
                        media_id INTEGER,
                        post_id INTEGER NOT NULL,
                        link VARCHAR,
                        directory VARCHAR,
                        filename VARCHAR,
                        size INTEGER,
                        api_type VARCHAR,
                        media_type VARCHAR,
                        preview INTEGER,
                        linked VARCHAR,
                        downloaded INTEGER,
                        created_at TIMESTAMP,
                        record_created_at TIMESTAMP,
                        PRIMARY KEY(id),
                        UNIQUE(media_id, api_type)
                    );

                    INSERT INTO medias SELECT * FROM old_medias;

                    DROP TABLE old_medias;

                    COMMIT;

                    PRAGMA foreign_keys=on;", connection))
                {
                    await cmd.ExecuteNonQueryAsync();
                }

                // create the 'messages' table
                using (SqliteCommand cmd = new("CREATE TABLE IF NOT EXISTS messages (id INTEGER NOT NULL, post_id INTEGER NOT NULL, text VARCHAR, price INTEGER, paid INTEGER, archived BOOLEAN, created_at TIMESTAMP, user_id INTEGER, record_created_at TIMESTAMP, PRIMARY KEY(id), UNIQUE(post_id));", connection))
                {
                    await cmd.ExecuteNonQueryAsync();
                }

                // create the 'posts' table
                using (SqliteCommand cmd = new("CREATE TABLE IF NOT EXISTS posts (id INTEGER NOT NULL, post_id INTEGER NOT NULL, text VARCHAR, price INTEGER, paid INTEGER, archived BOOLEAN, created_at TIMESTAMP, record_created_at TIMESTAMP, PRIMARY KEY(id), UNIQUE(post_id));", connection))
                {
                    await cmd.ExecuteNonQueryAsync();
                }

                // create the 'stories' table
                using (SqliteCommand cmd = new("CREATE TABLE IF NOT EXISTS stories (id INTEGER NOT NULL, post_id INTEGER NOT NULL, text VARCHAR, price INTEGER, paid INTEGER, archived BOOLEAN, created_at TIMESTAMP, record_created_at TIMESTAMP, PRIMARY KEY(id), UNIQUE(post_id));", connection))
                {
                    await cmd.ExecuteNonQueryAsync();
                }

                // create the 'others' table
                using (SqliteCommand cmd = new("CREATE TABLE IF NOT EXISTS others (id INTEGER NOT NULL, post_id INTEGER NOT NULL, text VARCHAR, price INTEGER, paid INTEGER, archived BOOLEAN, created_at TIMESTAMP, record_created_at TIMESTAMP, PRIMARY KEY(id), UNIQUE(post_id));", connection))
                {
                    await cmd.ExecuteNonQueryAsync();
                }

                // create the 'products' table
                using (SqliteCommand cmd = new("CREATE TABLE IF NOT EXISTS products (id INTEGER NOT NULL, post_id INTEGER NOT NULL, text VARCHAR, price INTEGER, paid INTEGER, archived BOOLEAN, created_at TIMESTAMP, title VARCHAR, record_created_at TIMESTAMP, PRIMARY KEY(id), UNIQUE(post_id));", connection))
                {
                    await cmd.ExecuteNonQueryAsync();
                }

                // create the 'profiles' table
                using (SqliteCommand cmd = new("CREATE TABLE IF NOT EXISTS profiles (id INTEGER NOT NULL, user_id INTEGER NOT NULL, username VARCHAR NOT NULL, record_created_at TIMESTAMP, PRIMARY KEY(id), UNIQUE(username));", connection))
                {
                    await cmd.ExecuteNonQueryAsync();
                }

                connection.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                Log.Error("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                if (ex.InnerException != null)
                {
                    Console.WriteLine("\nInner Exception:");
                    Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                    Log.Error("Inner Exception: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                }
            }
        }

        public async Task CreateUsersDB(Dictionary<string, int> users)
        {
            try
            {
                using SqliteConnection connection = new($"Data Source={Directory.GetCurrentDirectory()}/users.db");
                Log.Debug("Database data source: " + connection.DataSource);

                connection.Open();

                using (SqliteCommand cmd = new("CREATE TABLE IF NOT EXISTS users (id INTEGER NOT NULL, user_id INTEGER NOT NULL, username VARCHAR NOT NULL, PRIMARY KEY(id), UNIQUE(username));", connection))
                {
                    await cmd.ExecuteNonQueryAsync();
                }

                Log.Debug("Adding missing creators");
                foreach (KeyValuePair<string, int> user in users)
                {
                    using (SqliteCommand checkCmd = new($"SELECT user_id, username FROM users WHERE user_id = @userId;", connection))
                    {
                        checkCmd.Parameters.AddWithValue("@userId", user.Value);
                        using (var reader = await checkCmd.ExecuteReaderAsync())
                        {
                            if (!reader.Read())
                            {
                                using (SqliteCommand insertCmd = new($"INSERT INTO users (user_id, username) VALUES (@userId, @username);", connection))
                                {
                                    insertCmd.Parameters.AddWithValue("@userId", user.Value);
                                    insertCmd.Parameters.AddWithValue("@username", user.Key);
                                    await insertCmd.ExecuteNonQueryAsync();
                                    Log.Debug("Inserted new creator: " + user.Key);
                                }
                            }
                            else
                            {
                                Log.Debug("Creator " + user.Key + " already exists");
                            }
                        }
                    }
                }

                connection.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                Log.Error("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                if (ex.InnerException != null)
                {
                    Console.WriteLine("\nInner Exception:");
                    Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                    Log.Error("Inner Exception: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                }
            }
        }

        public async Task CheckUsername(KeyValuePair<string, int> user, string path)
        {
            try
            {
                using SqliteConnection connection = new($"Data Source={Directory.GetCurrentDirectory()}/users.db");

                connection.Open();

                using (SqliteCommand checkCmd = new($"SELECT user_id, username FROM users WHERE user_id = @userId;", connection))
                {
                    checkCmd.Parameters.AddWithValue("@userId", user.Value);
                    using (var reader = await checkCmd.ExecuteReaderAsync())
                    {
                        if (reader.Read())
                        {
                            long storedUserId = reader.GetInt64(0);
                            string storedUsername = reader.GetString(1);

                            if (storedUsername != user.Key)
                            {
                                using (SqliteCommand updateCmd = new($"UPDATE users SET username = @newUsername WHERE user_id = @userId;", connection))
                                {
                                    updateCmd.Parameters.AddWithValue("@newUsername", user.Key);
                                    updateCmd.Parameters.AddWithValue("@userId", user.Value);
                                    await updateCmd.ExecuteNonQueryAsync();
                                }

                                string oldPath = path.Replace(path.Split("/")[^1], storedUsername);

                                if (Directory.Exists(oldPath))
                                {
                                    Directory.Move(path.Replace(path.Split("/")[^1], storedUsername), path);
                                }
                            }
                        }
                    }
                }

                connection.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                Log.Error("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                if (ex.InnerException != null)
                {
                    Console.WriteLine("\nInner Exception:");
                    Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                    Log.Error("Inner Exception: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                }
            }
        }

        public async Task AddMessage(string folder, long post_id, string message_text, string price, bool is_paid, bool is_archived, DateTime created_at, int user_id)
        {
            try
            {
                using SqliteConnection connection = new($"Data Source={folder}/Metadata/user_data.db");
                connection.Open();
                await EnsureCreatedAtColumnExists(connection, "messages");
                using SqliteCommand cmd = new($"SELECT COUNT(*) FROM messages WHERE post_id=@post_id", connection);
                cmd.Parameters.AddWithValue("@post_id", post_id);
                int count = Convert.ToInt32(await cmd.ExecuteScalarAsync());
                if (count == 0)
                {
                    // If the record doesn't exist, insert a new one
                    using SqliteCommand insertCmd = new("INSERT INTO messages(post_id, text, price, paid, archived, created_at, user_id, record_created_at) VALUES(@post_id, @message_text, @price, @is_paid, @is_archived, @created_at, @user_id, @record_created_at)", connection);
                    insertCmd.Parameters.AddWithValue("@post_id", post_id);
                    insertCmd.Parameters.AddWithValue("@message_text", message_text ?? (object)DBNull.Value);
                    insertCmd.Parameters.AddWithValue("@price", price ?? (object)DBNull.Value);
                    insertCmd.Parameters.AddWithValue("@is_paid", is_paid);
                    insertCmd.Parameters.AddWithValue("@is_archived", is_archived);
                    insertCmd.Parameters.AddWithValue("@created_at", created_at);
                    insertCmd.Parameters.AddWithValue("@user_id", user_id);
                    insertCmd.Parameters.AddWithValue("@record_created_at", DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"));
                    await insertCmd.ExecuteNonQueryAsync();
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                Log.Error("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                if (ex.InnerException != null)
                {
                    Console.WriteLine("\nInner Exception:");
                    Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                    Log.Error("Inner Exception: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                }
            }
        }


        public async Task AddPost(string folder, long post_id, string message_text, string price, bool is_paid, bool is_archived, DateTime created_at)
        {
            try
            {
                using SqliteConnection connection = new($"Data Source={folder}/Metadata/user_data.db");
                connection.Open();
                await EnsureCreatedAtColumnExists(connection, "posts");
                using SqliteCommand cmd = new($"SELECT COUNT(*) FROM posts WHERE post_id=@post_id", connection);
                cmd.Parameters.AddWithValue("@post_id", post_id);
                int count = Convert.ToInt32(await cmd.ExecuteScalarAsync());
                if (count == 0)
                {
                    // If the record doesn't exist, insert a new one
                    using SqliteCommand insertCmd = new("INSERT INTO posts(post_id, text, price, paid, archived, created_at, record_created_at) VALUES(@post_id, @message_text, @price, @is_paid, @is_archived, @created_at, @record_created_at)", connection);
                    insertCmd.Parameters.AddWithValue("@post_id", post_id);
                    insertCmd.Parameters.AddWithValue("@message_text", message_text ?? (object)DBNull.Value);
                    insertCmd.Parameters.AddWithValue("@price", price ?? (object)DBNull.Value);
                    insertCmd.Parameters.AddWithValue("@is_paid", is_paid);
                    insertCmd.Parameters.AddWithValue("@is_archived", is_archived);
                    insertCmd.Parameters.AddWithValue("@created_at", created_at);
                    insertCmd.Parameters.AddWithValue("@record_created_at", DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"));
                    await insertCmd.ExecuteNonQueryAsync();
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                Log.Error("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                if (ex.InnerException != null)
                {
                    Console.WriteLine("\nInner Exception:");
                    Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                    Log.Error("Inner Exception: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                }
            }
        }


        public async Task AddStory(string folder, long post_id, string message_text, string price, bool is_paid, bool is_archived, DateTime created_at)
        {
            try
            {
                using SqliteConnection connection = new($"Data Source={folder}/Metadata/user_data.db");
                connection.Open();
                await EnsureCreatedAtColumnExists(connection, "stories");
                using SqliteCommand cmd = new($"SELECT COUNT(*) FROM stories WHERE post_id=@post_id", connection);
                cmd.Parameters.AddWithValue("@post_id", post_id);
                int count = Convert.ToInt32(await cmd.ExecuteScalarAsync());
                if (count == 0)
                {
                    // If the record doesn't exist, insert a new one
                    using SqliteCommand insertCmd = new("INSERT INTO stories(post_id, text, price, paid, archived, created_at, record_created_at) VALUES(@post_id, @message_text, @price, @is_paid, @is_archived, @created_at, @record_created_at)", connection);
                    insertCmd.Parameters.AddWithValue("@post_id", post_id);
                    insertCmd.Parameters.AddWithValue("@message_text", message_text ?? (object)DBNull.Value);
                    insertCmd.Parameters.AddWithValue("@price", price ?? (object)DBNull.Value);
                    insertCmd.Parameters.AddWithValue("@is_paid", is_paid);
                    insertCmd.Parameters.AddWithValue("@is_archived", is_archived);
                    insertCmd.Parameters.AddWithValue("@created_at", created_at);
                    insertCmd.Parameters.AddWithValue("@record_created_at", DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"));
                    await insertCmd.ExecuteNonQueryAsync();
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                Log.Error("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                if (ex.InnerException != null)
                {
                    Console.WriteLine("\nInner Exception:");
                    Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                    Log.Error("Inner Exception: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                }
            }
        }


        public async Task AddMedia(string folder, long media_id, long post_id, string link, string? directory, string? filename, long? size, string api_type, string media_type, bool preview, bool downloaded, DateTime? created_at)
        {
            try
            {
                using SqliteConnection connection = new($"Data Source={folder}/Metadata/user_data.db");
                connection.Open();
                await EnsureCreatedAtColumnExists(connection, "medias");
                StringBuilder sql = new StringBuilder("SELECT COUNT(*) FROM medias WHERE media_id=@media_id");
                if (downloadConfig.DownloadDuplicatedMedia)
                {
                    sql.Append(" and api_type=@api_type");
                }

                using SqliteCommand cmd = new(sql.ToString(), connection);
                cmd.Parameters.AddWithValue("@media_id", media_id);
                cmd.Parameters.AddWithValue("@api_type", api_type);
                int count = Convert.ToInt32(cmd.ExecuteScalar());
                if (count == 0)
                {
                    // If the record doesn't exist, insert a new one
                    using SqliteCommand insertCmd = new($"INSERT INTO medias(media_id, post_id, link, directory, filename, size, api_type, media_type, preview, downloaded, created_at, record_created_at) VALUES({media_id}, {post_id}, '{link}', '{directory?.ToString() ?? "NULL"}', '{filename?.ToString() ?? "NULL"}', {size?.ToString() ?? "NULL"}, '{api_type}', '{media_type}', {Convert.ToInt32(preview)}, {Convert.ToInt32(downloaded)}, '{created_at?.ToString("yyyy-MM-dd HH:mm:ss")}', '{DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss")}')", connection);
                    await insertCmd.ExecuteNonQueryAsync();
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                Log.Error("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                if (ex.InnerException != null)
                {
                    Console.WriteLine("\nInner Exception:");
                    Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                    Log.Error("Inner Exception: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                }
            }
        }


        public async Task<bool> CheckDownloaded(string folder, long media_id, string api_type)
        {
            try
            {
                bool downloaded = false;

                using (SqliteConnection connection = new($"Data Source={folder}/Metadata/user_data.db"))
                {
                    StringBuilder sql = new StringBuilder("SELECT downloaded FROM medias WHERE media_id=@media_id");
                    if(downloadConfig.DownloadDuplicatedMedia)
                    {
                        sql.Append(" and api_type=@api_type");
                    }

                    connection.Open();
                    using SqliteCommand cmd = new (sql.ToString(), connection);
                    cmd.Parameters.AddWithValue("@media_id", media_id);
                    cmd.Parameters.AddWithValue("@api_type", api_type);
                    downloaded = Convert.ToBoolean(await cmd.ExecuteScalarAsync());
                }
                return downloaded;
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                Log.Error("Exception caught: {0}\n\nStackTrace: {1}", ex.Message, ex.StackTrace);
                if (ex.InnerException != null)
                {
                    Console.WriteLine("\nInner Exception:");
                    Console.WriteLine("Exception caught: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                    Log.Error("Inner Exception: {0}\n\nStackTrace: {1}", ex.InnerException.Message, ex.InnerException.StackTrace);
                }
            }
            return false;
        }


        public async Task UpdateMedia(string folder, long media_id, string api_type, string directory, string filename, long size, bool downloaded, DateTime created_at)
        {
            using SqliteConnection connection = new($"Data Source={folder}/Metadata/user_data.db");
            connection.Open();

            // Construct the update command
            StringBuilder sql = new StringBuilder("UPDATE medias SET directory=@directory, filename=@filename, size=@size, downloaded=@downloaded, created_at=@created_at WHERE media_id=@media_id");
            if (downloadConfig.DownloadDuplicatedMedia)
            {
                sql.Append(" and api_type=@api_type");
            }

            // Create a new command object
            using SqliteCommand command = new(sql.ToString(), connection);
            // Add parameters to the command object
            command.Parameters.AddWithValue("@directory", directory);
            command.Parameters.AddWithValue("@filename", filename);
            command.Parameters.AddWithValue("@size", size);
            command.Parameters.AddWithValue("@downloaded", downloaded ? 1 : 0);
            command.Parameters.AddWithValue("@created_at", created_at);
            command.Parameters.AddWithValue("@media_id", media_id);
            command.Parameters.AddWithValue("@api_type", api_type);

            // Execute the command
            await command.ExecuteNonQueryAsync();
        }


        public async Task<long> GetStoredFileSize(string folder, long media_id, string api_type)
        {
            long size;
            using (SqliteConnection connection = new($"Data Source={folder}/Metadata/user_data.db"))
            {
                connection.Open();
                using SqliteCommand cmd = new($"SELECT size FROM medias WHERE media_id=@media_id and api_type=@api_type", connection);
                cmd.Parameters.AddWithValue("@media_id", media_id);
                cmd.Parameters.AddWithValue("@api_type", api_type);
                size = Convert.ToInt64(await cmd.ExecuteScalarAsync());
            }
            return size;
        }

        public async Task<DateTime?> GetMostRecentPostDate(string folder)
        {
            DateTime? mostRecentDate = null;
            using (SqliteConnection connection = new($"Data Source={folder}/Metadata/user_data.db"))
            {
                connection.Open();
                using SqliteCommand cmd = new(@"
                    SELECT
	                    MIN(created_at) AS created_at
                    FROM  (
		                    SELECT MAX(P.created_at) AS created_at
		                    FROM   posts AS P
		                    LEFT OUTER JOIN medias AS m
				                    ON P.post_id = m.post_id
			                       AND m.downloaded = 1
	                        UNION
		                    SELECT MIN(P.created_at) AS created_at
		                    FROM   posts AS P
		                    INNER JOIN medias AS m
				                    ON P.post_id = m.post_id
		                    WHERE m.downloaded = 0 
	                      )", connection);
                var scalarValue = await cmd.ExecuteScalarAsync();
                if(scalarValue != null && scalarValue != DBNull.Value)
                {
                    mostRecentDate = Convert.ToDateTime(scalarValue);
                }
            }
            return mostRecentDate;
        }

        private async Task EnsureCreatedAtColumnExists(SqliteConnection connection, string tableName)
        {
            using SqliteCommand cmd = new($"PRAGMA table_info({tableName});", connection);
            using var reader = await cmd.ExecuteReaderAsync();
            bool columnExists = false;

            while (await reader.ReadAsync())
            {
                if (reader["name"].ToString() == "record_created_at")
                {
                    columnExists = true;
                    break;
                }
            }

            if (!columnExists)
            {
                using SqliteCommand alterCmd = new($"ALTER TABLE {tableName} ADD COLUMN record_created_at TIMESTAMP;", connection);
                await alterCmd.ExecuteNonQueryAsync();
            }
        }
    }
}