using StackExchange.Redis;
using System;
using System.Collections.Generic;
using System.Linq;

namespace RedisManager.Utils
{
    /// <summary>
    /// Provides utility methods for Redis operations, including instance retrieval, connection, array conversion, and table printing.
    /// </summary>
    public static class RedisUtils
    {
        /// <summary>
        /// Retrieves an InstanceConfig by name from the provided configuration. Exits if not found.
        /// </summary>
        /// <param name="config">The configuration containing Redis instances.</param>
        /// <param name="name">The name of the instance to retrieve.</param>
        /// <returns>The matching InstanceConfig.</returns>
        public static InstanceConfig GetInstance(Config config, string name)
        {
            var instance = config.Instances.Find(i => i.Name == name);
            if (instance == null)
            {
                Console.WriteLine(Output.Red($"Instance '{name}' not found."));
                Environment.Exit(1);
            }
            return instance;
        }

        /// <summary>
        /// Connects to a Redis instance using the provided configuration.
        /// </summary>
        /// <param name="instance">The instance configuration to connect with.</param>
        /// <returns>A connected ConnectionMultiplexer.</returns>
        public static ConnectionMultiplexer ConnectRedis(InstanceConfig instance)
        {
            var options = new ConfigurationOptions
            {
                EndPoints = { $"{instance.Host}:{instance.Port}" },
                Password = instance.Password
            };
            return ConnectionMultiplexer.Connect(options);
        }

        /// <summary>
        /// Converts an enumerable of strings to a RedisValue array.
        /// </summary>
        /// <param name="values">The string values to convert.</param>
        /// <returns>An array of RedisValue.</returns>
        public static RedisValue[] ArrayFrom(IEnumerable<string> values)
        {
            var list = new List<RedisValue>();
            foreach (var v in values)
                list.Add(v);
            return list.ToArray();
        }

        /// <summary>
        /// Converts an enumerable of strings to a RedisKey array.
        /// </summary>
        /// <param name="values">The string values to convert.</param>
        /// <returns>An array of RedisKey.</returns>
        public static RedisKey[] ArrayFromKeys(IEnumerable<string> values)
        {
            var list = new List<RedisKey>();
            foreach (var v in values)
                list.Add(v);
            return list.ToArray();
        }

        /// <summary>
        /// Prints a formatted table to the console with headers and rows.
        /// </summary>
        /// <param name="headers">The column headers.</param>
        /// <param name="rows">The table rows.</param>
        public static void PrintTable(string[] headers, List<string[]> rows)
        {
            if (rows.Count == 0)
            {
                Console.WriteLine(Output.Yellow("No data"));
                return;
            }

            // Calculate column widths
            var widths = new int[headers.Length];
            for (int i = 0; i < headers.Length; i++)
            {
                widths[i] = headers[i].Length;
                foreach (var row in rows)
                {
                    if (i < row.Length && row[i] != null)
                        widths[i] = Math.Max(widths[i], row[i].Length);
                }
            }

            // Print header
            Console.WriteLine(Output.Blue(string.Join(" | ", headers.Select((h, i) => h.PadRight(widths[i])))));
            Console.WriteLine(Output.Blue(new string('-', widths.Sum() + (headers.Length - 1) * 3)));

            // Print rows
            foreach (var row in rows)
            {
                var formattedRow = new string[headers.Length];
                for (int i = 0; i < headers.Length; i++)
                {
                    formattedRow[i] = i < row.Length && row[i] != null ? row[i].PadRight(widths[i]) : "".PadRight(widths[i]);
                }
                Console.WriteLine(Output.Green(string.Join(" | ", formattedRow)));
            }
        }
    }
}