using System;
using System.Collections.Generic;
using Microsoft.AspNetCore.Mvc;
using Umbraco.Core;
using Umbraco.Core.Logging.Viewer;
using Umbraco.Core.Models;
using Umbraco.Web.Common.Attributes;
using Umbraco.Web.Common.Exceptions;
using Umbraco.Web.Editors;

namespace Umbraco.Web.BackOffice.Controllers
{
    /// <summary>
    /// Backoffice controller supporting the dashboard for viewing logs with some simple graphs & filtering
    /// </summary>
    [PluginController(Constants.Web.Mvc.BackOfficeApiArea)]
    public class LogViewerController : UmbracoAuthorizedJsonController
    {
        private readonly ILogViewer _logViewer;

        public LogViewerController(ILogViewer logViewer)
        {
            _logViewer = logViewer ?? throw new ArgumentNullException(nameof(logViewer));
        }

        private bool CanViewLogs(LogTimePeriod logTimePeriod)
        {
            //Can the interface deal with Large Files
            if (_logViewer.CanHandleLargeLogs)
                return true;

            //Interface CheckCanOpenLogs
            return _logViewer.CheckCanOpenLogs(logTimePeriod);
        }

        [HttpGet]
        public bool GetCanViewLogs([FromQuery] DateTime? startDate = null,[FromQuery] DateTime? endDate = null)
        {
            var logTimePeriod = GetTimePeriod(startDate, endDate);
            return CanViewLogs(logTimePeriod);
        }

        [HttpGet]
        public int GetNumberOfErrors([FromQuery] DateTime? startDate = null,[FromQuery] DateTime? endDate = null)
        {
            var logTimePeriod = GetTimePeriod(startDate, endDate);
            //We will need to stop the request if trying to do this on a 1GB file
            if (CanViewLogs(logTimePeriod) == false)
            {
                throw HttpResponseException.CreateNotificationValidationErrorResponse("Unable to view logs, due to size");
            }

            return _logViewer.GetNumberOfErrors(logTimePeriod);
        }

        [HttpGet]
        public LogLevelCounts GetLogLevelCounts([FromQuery] DateTime? startDate = null,[FromQuery] DateTime? endDate = null)
        {
            var logTimePeriod = GetTimePeriod(startDate, endDate);
            //We will need to stop the request if trying to do this on a 1GB file
            if (CanViewLogs(logTimePeriod) == false)
            {
                throw HttpResponseException.CreateNotificationValidationErrorResponse("Unable to view logs, due to size");
            }

            return _logViewer.GetLogLevelCounts(logTimePeriod);
        }

        [HttpGet]
        public IEnumerable<LogTemplate> GetMessageTemplates([FromQuery] DateTime? startDate = null,[FromQuery] DateTime? endDate = null)
        {
            var logTimePeriod = GetTimePeriod(startDate, endDate);
            //We will need to stop the request if trying to do this on a 1GB file
            if (CanViewLogs(logTimePeriod) == false)
            {
                throw HttpResponseException.CreateNotificationValidationErrorResponse("Unable to view logs, due to size");
            }

            return _logViewer.GetMessageTemplates(logTimePeriod);
        }

        [HttpGet]
        public PagedResult<LogMessage> GetLogs(string orderDirection = "Descending", int pageNumber = 1, string filterExpression = null, [FromQuery]string[] logLevels = null, [FromQuery] DateTime? startDate = null,[FromQuery] DateTime? endDate = null)
        {
            var logTimePeriod = GetTimePeriod(startDate, endDate);

            //We will need to stop the request if trying to do this on a 1GB file
            if (CanViewLogs(logTimePeriod) == false)
            {
                throw HttpResponseException.CreateNotificationValidationErrorResponse("Unable to view logs, due to size");
            }

            var direction = orderDirection == "Descending" ? Direction.Descending : Direction.Ascending;

            return _logViewer.GetLogs(logTimePeriod, filterExpression: filterExpression, pageNumber: pageNumber, orderDirection: direction, logLevels: logLevels);
        }

        private static LogTimePeriod GetTimePeriod(DateTime? startDate, DateTime? endDate)
        {
            if (startDate == null || endDate == null)
            {
                var now = DateTime.Now;
                if (startDate == null)
                {
                    startDate = now.AddDays(-1);
                }

                if (endDate == null)
                {
                    endDate = now;
                }
            }

            return new LogTimePeriod(startDate.Value, endDate.Value);
        }

        [HttpGet]
        public IEnumerable<SavedLogSearch> GetSavedSearches()
        {
            return _logViewer.GetSavedSearches();
        }

        [HttpPost]
        public IEnumerable<SavedLogSearch> PostSavedSearch(SavedLogSearch item)
        {
            return _logViewer.AddSavedSearch(item.Name, item.Query);
        }

        [HttpPost]
        public IEnumerable<SavedLogSearch> DeleteSavedSearch(SavedLogSearch item)
        {
            return _logViewer.DeleteSavedSearch(item.Name, item.Query);
        }

        [HttpGet]
        public string GetLogLevel()
        {
            return _logViewer.GetLogLevel();
        }
    }
}