using System;
using System.Collections.Generic;
using Newtonsoft.Json.Linq;
using PSProxmoxVE.Core.Authentication;
using PSProxmoxVE.Core.Client;
using PSProxmoxVE.Core.Models.Backup;
using PSProxmoxVE.Core.Models.Vms;

namespace PSProxmoxVE.Core.Services
{
    /// <summary>
    /// Service for Proxmox VE Backup (vzdump) and backup job API operations.
    /// </summary>
    public class BackupService
    {
        // -------------------------------------------------------------------------
        // Ad-hoc backup (vzdump)
        // -------------------------------------------------------------------------

        /// <summary>
        /// Creates an ad-hoc backup via vzdump. Returns the task UPID.
        /// </summary>
        /// <param name="session">The authenticated PVE session.</param>
        /// <param name="node">The node to run the backup on.</param>
        /// <param name="config">Backup configuration parameters.</param>
        public PveTask CreateBackup(PveSession session, string node, Dictionary<string, string> config)
        {
            if (session == null) throw new ArgumentNullException(nameof(session));
            if (string.IsNullOrWhiteSpace(node)) throw new ArgumentNullException(nameof(node));
            if (config == null) throw new ArgumentNullException(nameof(config));

            using var client = new PveHttpClient(session);
            var response = client.PostAsync($"nodes/{Uri.EscapeDataString(node)}/vzdump", config)
                .GetAwaiter().GetResult();
            return ParseTask(response, node);
        }

        // -------------------------------------------------------------------------
        // Backup jobs (scheduled)
        // -------------------------------------------------------------------------

        /// <summary>
        /// Returns all scheduled backup jobs.
        /// </summary>
        public PveBackupJob[] GetBackupJobs(PveSession session)
        {
            if (session == null) throw new ArgumentNullException(nameof(session));

            using var client = new PveHttpClient(session);
            var response = client.GetAsync("cluster/backup").GetAwaiter().GetResult();
            var data = JObject.Parse(response)["data"];
            return data?.ToObject<PveBackupJob[]>() ?? Array.Empty<PveBackupJob>();
        }

        /// <summary>
        /// Returns a single scheduled backup job by ID.
        /// </summary>
        public PveBackupJob? GetBackupJob(PveSession session, string id)
        {
            if (session == null) throw new ArgumentNullException(nameof(session));
            if (string.IsNullOrWhiteSpace(id)) throw new ArgumentNullException(nameof(id));

            using var client = new PveHttpClient(session);
            var response = client.GetAsync($"cluster/backup/{Uri.EscapeDataString(id)}")
                .GetAwaiter().GetResult();
            var data = JObject.Parse(response)["data"];
            return data?.ToObject<PveBackupJob>();
        }

        /// <summary>
        /// Creates a scheduled backup job.
        /// </summary>
        public void CreateBackupJob(PveSession session, Dictionary<string, string> config)
        {
            if (session == null) throw new ArgumentNullException(nameof(session));
            if (config == null) throw new ArgumentNullException(nameof(config));

            using var client = new PveHttpClient(session);
            client.PostAsync("cluster/backup", config).GetAwaiter().GetResult();
        }

        /// <summary>
        /// Updates a scheduled backup job.
        /// </summary>
        public void UpdateBackupJob(PveSession session, string id, Dictionary<string, string> config)
        {
            if (session == null) throw new ArgumentNullException(nameof(session));
            if (string.IsNullOrWhiteSpace(id)) throw new ArgumentNullException(nameof(id));
            if (config == null) throw new ArgumentNullException(nameof(config));

            using var client = new PveHttpClient(session);
            client.PutAsync($"cluster/backup/{Uri.EscapeDataString(id)}", config)
                .GetAwaiter().GetResult();
        }

        /// <summary>
        /// Removes a scheduled backup job.
        /// </summary>
        public void RemoveBackupJob(PveSession session, string id)
        {
            if (session == null) throw new ArgumentNullException(nameof(session));
            if (string.IsNullOrWhiteSpace(id)) throw new ArgumentNullException(nameof(id));

            using var client = new PveHttpClient(session);
            client.DeleteAsync($"cluster/backup/{Uri.EscapeDataString(id)}")
                .GetAwaiter().GetResult();
        }

        // -------------------------------------------------------------------------
        // Private helpers
        // -------------------------------------------------------------------------

        private static PveTask ParseTask(string response, string node)
        {
            var data = JObject.Parse(response)["data"];
            if (data?.Type == JTokenType.String)
                return new PveTask { Upid = data.ToString(), Node = node };

            var task = data?.ToObject<PveTask>() ?? new PveTask();
            task.Node = node;
            return task;
        }
    }
}