using System;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Routing;
using Microsoft.AspNetCore.Authorization;
using Microsoft.Extensions.Logging;

using AyaNova.Models;
using AyaNova.Api.ControllerHelpers;
using AyaNova.Biz;
using System.ComponentModel.DataAnnotations;



namespace AyaNova.Api.Controllers
{

    /// <summary>
    /// License route
    /// </summary>    
    [ApiController]
    [Asp.Versioning.ApiVersion("8.0")]
    [Route("api/v{version:apiVersion}/license")]
    [Produces("application/json")]
    [Authorize]
    public class LicenseController : ControllerBase
    {
        private readonly AyContext ct;
        private readonly ILogger<LicenseController> log;
        private readonly ApiServerState serverState;


        /// <summary>
        /// ctor
        /// </summary>
        /// <param name="dbcontext"></param>
        /// <param name="logger"></param>
        /// <param name="apiServerState"></param>
        public LicenseController(AyContext dbcontext, ILogger<LicenseController> logger, ApiServerState apiServerState)
        {
            ct = dbcontext;
            log = logger;
            serverState = apiServerState;
        }




        /// <summary>
        /// Get License info
        /// </summary>       
        /// <returns>Information about the currently installed license in AyaNova</returns>
        [HttpGet()]
        public ActionResult GetLicenseInfo()
        {
            if (serverState.IsClosed)
            {
                //Exception for SuperUser account to handle licensing issues
                if (UserIdFromContext.Id(HttpContext.Items) != 1)
                    return StatusCode(503, new ApiErrorResponse(serverState.ApiErrorCode, null, serverState.Reason));
            }
            if (!Authorized.HasReadFullRole(HttpContext.Items, AyaType.License))
            {
                return StatusCode(403, new ApiNotAuthorizedResponse());
            }

            var ret = AyaNova.Core.License.LicenseInfoAsJson;

            return Ok(ApiOkResponse.Response(ret));
        }

        /// <summary>
        /// Get DB Emptiness
        /// </summary>       
        /// <returns>Checks if there is any data in critical tables only</returns>
        [HttpGet("database-empty")]
        public async Task<IActionResult> GetDbEmpty()
        {
            if (serverState.IsClosed)
            {
                //Exception for SuperUser account to handle licensing issues
                if (UserIdFromContext.Id(HttpContext.Items) != 1)
                    return StatusCode(503, new ApiErrorResponse(serverState.ApiErrorCode, null, serverState.Reason));
            }
            if (!Authorized.HasReadFullRole(HttpContext.Items, AyaType.License))
            {
                return StatusCode(403, new ApiNotAuthorizedResponse());
            }
            return Ok(ApiOkResponse.Response(await AyaNova.Util.DbUtil.DBIsEmptyAsync(ct, log)));
        }





        /// <summary>
        /// Fetch license
        /// 
        /// Posting to this route causes AyaNova to attempt to refresh it's license 
        /// from the AyaNova license server
        /// </summary>    
        /// <returns>On success returns information about the currently installed license in AyaNova</returns>
        [HttpPost]
        public async Task<IActionResult> FetchLicense()
        {
            if (serverState.IsClosed)
            {
                //Exception for SuperUser account to handle licensing issues
                if (UserIdFromContext.Id(HttpContext.Items) != 1)
                    return StatusCode(503, new ApiErrorResponse(serverState.ApiErrorCode, null, serverState.Reason));
            }
            if (!Authorized.HasCreateRole(HttpContext.Items, AyaType.License))
            {
                return StatusCode(403, new ApiNotAuthorizedResponse());
            }

            if (!ModelState.IsValid)
            {
                return BadRequest(new ApiErrorResponse(ModelState));
            }

            try
            {
                var ret = await AyaNova.Core.License.FetchKeyAsync(serverState, ct, log, false);
                //most often the result will be not found but in future might be other results
                //main thing is to not log anything but OK response
                if (ret == "ok")
                {
                    //Eventlog
                    await EventLogProcessor.LogEventToDatabaseAsync(new Event(UserIdFromContext.Id(HttpContext.Items), 0, AyaType.License, AyaEvent.LicenseFetch), ct);
                }
                else
                {
                    if (ret != "notfound")
                        log.LogError($"LicenseController::FetchLicense - failed: {ret}");
                }

                //any response here is OK, there's not necessarily an error, just no key or some mundane problem not technical but biz so let 
                //ret string instruct client on what to do
                return Ok(ret);
            }
            catch (Exception ex)
            {
                Exception rootex = ex;
                while (rootex.InnerException != null)
                {
                    rootex = rootex.InnerException;
                }

                if (rootex.Message.Contains("E1020"))
                {
                    return BadRequest(new ApiErrorResponse(ApiErrorCode.INVALID_OPERATION, "LICENSE_KEY", rootex.Message));
                }
                else
                {
                    throw;
                }

            }
        }



        /// <summary>
        /// Request trial license
        /// 
        /// Posting to this route causes AyaNova to request a trial license key from the AyaNova license server
        /// Database must be empty and unlicensed or trial license
        /// </summary>
        /// <param name="trialRequest"></param>
        /// <returns>HTTP 204 No Content result code on success or fail code with explanation</returns>
        [HttpPost("trialRequest")]
        public async Task<IActionResult> RequestTrial([FromBody] RequestTrial trialRequest)
        {
            if (serverState.IsClosed)
            {
                //Exception for SuperUser account to handle licensing issues
                if (UserIdFromContext.Id(HttpContext.Items) != 1)
                    return StatusCode(503, new ApiErrorResponse(serverState.ApiErrorCode, null, serverState.Reason));
            }
            if (!Authorized.HasCreateRole(HttpContext.Items, AyaType.License))
            {
                return StatusCode(403, new ApiNotAuthorizedResponse());
            }

            if (!ModelState.IsValid)
            {
                return BadRequest(new ApiErrorResponse(ModelState));
            }

            if (!await AyaNova.Util.DbUtil.DBIsEmptyAsync(ct, log))
            {
                return BadRequest(new ApiErrorResponse(ApiErrorCode.INVALID_OPERATION, null, "Only an empty AyaNova database can request a trial key. Erase the database to proceed with a new trial."));
            }

            if (!AyaNova.Core.License.ActiveKey.IsEmpty && !AyaNova.Core.License.ActiveKey.TrialLicense)
            {
                return BadRequest(new ApiErrorResponse(ApiErrorCode.INVALID_OPERATION, null, "There is an active registered license. Only an unlicensed or trial license database can request a trial key."));
            }
            try
            {
                //Send the request to RockFish here (or at least start the job to do it in which case return Accepted instead of no content and update comment above)
                var ret = await Core.License.RequestTrialAsync(trialRequest, log);
                if (ret == "ok")
                {
                    //Log
                    await EventLogProcessor.LogEventToDatabaseAsync(new Event(UserIdFromContext.Id(HttpContext.Items), 0, AyaType.License, AyaEvent.LicenseTrialRequest), ct);
                }
                return Ok(ret);
            }
            catch (Exception ex)
            {
                Exception rootex = ex;
                while (rootex.InnerException != null)
                {
                    rootex = rootex.InnerException;
                }

                if (rootex.Message.Contains("E1020"))
                {
                    return BadRequest(new ApiErrorResponse(ApiErrorCode.INVALID_OPERATION, "LICENSE_KEY", rootex.Message));
                }
                else
                {
                    throw;
                }

            }
        }




        /// <summary>
        /// Permanently erase most data and all attachments for seeding or migration purposes
        /// 
        /// This route is used by the v8-migration utility and by the AyaNova UI when seeding a trial database
        ///
        /// Items retained are documented here with the exception of Tax codes:
        /// https://ayanova.com/docs/adm-license/#erase-database
        /// However not Tax Codes as documented because seeding or migration will create tax codes
        /// 
        /// (Only *the* SuperUser account can use this route)
        /// </summary>
        /// <param name="acceptCode">Must be "I understand"</param>
        /// <returns>HTTP 204 No Content result code on success or fail code with explanation</returns>
        [HttpPost("permanently-erase-all-data")]
        public async Task<IActionResult> RemoveAllData([FromBody] string acceptCode)
        {
            if (serverState.IsClosed)
            {
                //Exception for SuperUser account to handle licensing issues
                if (UserIdFromContext.Id(HttpContext.Items) != 1)
                    return StatusCode(503, new ApiErrorResponse(serverState.ApiErrorCode, null, serverState.Reason));
            }
            if (!ModelState.IsValid)
                return BadRequest(new ApiErrorResponse(ModelState));

            long UserId = UserIdFromContext.Id(HttpContext.Items);

            //SuperUser only and must have accept code
            if (UserId != 1 || string.IsNullOrWhiteSpace(acceptCode) || acceptCode.ToLowerInvariant() != "i understand")
                return StatusCode(403, new ApiNotAuthorizedResponse());



            //empty the db
            await AyaNova.Util.DbUtil.EmptyBizDataFromDatabaseForSeedingOrImportingAsync(log);

            //Log
            await EventLogProcessor.LogEventToDatabaseAsync(new Event(1, 0, AyaType.Global, AyaEvent.EraseAllData), ct);

            return NoContent();
        }



        /// <summary>
        /// Permanently erase most data and all attachments
        /// 
        /// This route is used by the by the AyaNova UI when a user selects to manually erase the database
        /// or when they are evaluating and request another trial period with a database that already has a trial license in it
        ///
        /// Items retained are documented here:
        /// https://ayanova.com/docs/adm-license/#erase-database
        /// 
        /// 
        /// (Only *the* SuperUser account can use this route)
        /// </summary>
        /// <param name="acceptCode">Must be "I understand"</param>
        /// <returns>HTTP 204 No Content result code on success or fail code with explanation</returns>
        [HttpPost("permanently-erase-all-data-keep-tax-codes")]
        public async Task<IActionResult> RemoveAllDataKeepTaxCodes([FromBody] string acceptCode)
        {
            if (serverState.IsClosed)
            {
                //Exception for SuperUser account to handle licensing issues
                if (UserIdFromContext.Id(HttpContext.Items) != 1)
                    return StatusCode(503, new ApiErrorResponse(serverState.ApiErrorCode, null, serverState.Reason));
            }
            if (!ModelState.IsValid)
                return BadRequest(new ApiErrorResponse(ModelState));

            long UserId = UserIdFromContext.Id(HttpContext.Items);

            //SuperUser only and must have accept code
            if (UserId != 1 || string.IsNullOrWhiteSpace(acceptCode) || acceptCode.ToLowerInvariant() != "i understand")
                return StatusCode(403, new ApiNotAuthorizedResponse());


            //empty the db
            await AyaNova.Util.DbUtil.EmptyBizDataFromDatabaseForSeedingOrImportingAsync(log, true);

            //Log
            await EventLogProcessor.LogEventToDatabaseAsync(new Event(1, 0, AyaType.Global, AyaEvent.EraseAllData), ct);

            return NoContent();
        }


        /// <summary>
        /// 
        /// </summary>
        /// <param name="acceptCode"></param>
        /// <returns>HTTP 204 No Content result code on success or fail code with explanation</returns>
        [AllowAnonymous]
        [HttpPost("lc")]
        [ApiExplorerSettings(IgnoreApi = true)]
        public async Task<IActionResult> lc([FromBody] string acceptCode)
        {
            //END USER LICENSE AGREEMENT ROUTE ONLY CALLED FROM WEBAPP AND HIDDEN FROM VIEW AS A ROUTE


            //SuperUser only and must have accept code
            if (string.IsNullOrWhiteSpace(acceptCode) || acceptCode.ToLowerInvariant() != "iaccepttheagreement")
                return StatusCode(403, new ApiNotAuthorizedResponse());

            await Core.License.FlagEULA(ct, log);

            //Log
            await EventLogProcessor.LogEventToDatabaseAsync(new Event(1, 0, AyaType.Global, AyaEvent.Modified, "End user license agreement consent obtained"), ct);

            return NoContent();
        }



        //------------------------------------------------------






    }//eoc
}//eons