using Api.SeaHavenIndustries.Helper;
using Data.SeaHavenIndustries;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Logging;
using SeaHaven.Services.DTOs;
using SeaHaven.Services.Interfaces;

namespace Api.SeaHavenIndustries.Controllers
{
    [ApiController]
    [Route("api/vendor-portal")]
    [Route("api/vendorportal")]
    public class VendorPortalController : Controller
    {
        private const string TokenHeader = "X-Vendor-Token";

        private readonly IVendorPortalService _portalService;
        private readonly ILogger<VendorPortalController> _logger;

        public VendorPortalController(IVendorPortalService portalService, ILogger<VendorPortalController> logger)
        {
            _portalService = portalService;
            _logger = logger;
        }

        [HttpGet("session")]
        public async Task<IActionResult> Session(CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            return Ok(new DataResponse
            {
                Status = "Success",
                Data = session
            });
        }

        [HttpGet("dispatches")]
        public async Task<IActionResult> ListDispatches([FromQuery] string? status = null, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            var dispatches = await _portalService.ListDispatchesAsync(session, status, cancellationToken);
            return Ok(new DataResponse { Status = "Success", Data = dispatches });
        }

        [HttpGet("dispatches/{id:int}")]
        public async Task<IActionResult> GetDispatch(int id, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            var detail = await _portalService.GetDispatchDetailAsync(session, id, cancellationToken);
            if (detail == null) return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });

            return Ok(new DataResponse { Status = "Success", Data = detail });
        }

        [HttpPost("dispatches/{id:int}/accept")]
        public async Task<IActionResult> Accept(int id, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                var result = await _portalService.AcceptDispatchAsync(session, id, cancellationToken);
                return Ok(new DataResponse { Status = "Success", Data = result });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The requested action could not be completed for this dispatch") });
            }
        }

        [HttpPost("dispatches/{id:int}/refuse")]
        public async Task<IActionResult> Refuse(int id, [FromBody] RefuseRequest? body, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                var result = await _portalService.RefuseDispatchAsync(session, id, body?.Reason, cancellationToken);
                return Ok(new DataResponse { Status = "Success", Data = result });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The requested action could not be completed for this dispatch") });
            }
        }

        [HttpPost("dispatches/{id:int}/status")]
        public async Task<IActionResult> ChangeStatus(int id, [FromBody] ChangeStatusRequest body, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                var result = await _portalService.ChangeStatusAsync(session, id, body?.Status, cancellationToken);
                return Ok(new DataResponse { Status = "Success", Data = result });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The requested action could not be completed for this dispatch") });
            }
        }

        [HttpPost("dispatches/{id:int}/request-cancel")]
        public async Task<IActionResult> RequestCancel(int id, [FromBody] RequestCancelRequest body, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                await _portalService.RequestCancelAsync(session, id, body?.Reason, cancellationToken);
                return Ok(new DataResponse { Status = "Success", Message = "Cancel request sent to dispatcher" });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The requested action could not be completed for this dispatch") });
            }
        }

        [HttpPost("dispatches/{id:int}/checklist/{itemId:int}")]
        public async Task<IActionResult> UpdateChecklistItem(int id, int itemId, [FromBody] ChecklistUpdateRequest body, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                var result = await _portalService.UpdateChecklistItemAsync(session, id, itemId, body.IsCompleted, cancellationToken);
                return Ok(new DataResponse { Status = "Success", Data = result });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The requested action could not be completed for this dispatch") });
            }
        }

        [HttpPost("dispatches/{id:int}/signoff")]
        public async Task<IActionResult> AddSignoff(int id, [FromBody] SignoffRequest body, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                var result = await _portalService.AddSignoffAsync(session, id, body?.SignoffType, body?.Name, body?.Signature, body?.SignatureMethod, cancellationToken);
                return Ok(new DataResponse { Status = "Success", Data = result });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The requested action could not be completed for this dispatch") });
            }
        }

        [HttpPost("dispatches/{id:int}/comments")]
        public async Task<IActionResult> AddComment(int id, [FromBody] CommentRequest body, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                var result = await _portalService.AddCommentAsync(session, id, body?.CommentText, cancellationToken);
                return Ok(new DataResponse { Status = "Success", Data = result });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The requested action could not be completed for this dispatch") });
            }
        }

        [HttpPost("dispatches/{id:int}/uplift-request")]
        public async Task<IActionResult> RequestUplift(int id, [FromBody] UpliftRequestBody body, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                var result = await _portalService.RequestUpliftAsync(session, id, body?.RequestedNTE ?? 0m, body?.Reason, body?.RequestKey, body?.EvidenceDocumentId, cancellationToken);
                return Ok(new DataResponse { Status = "Success", Data = result });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The requested action could not be completed for this dispatch") });
            }
        }

        [HttpPost("dispatches/{id:int}/uplift-request/{requestId:int}/cancel")]
        public async Task<IActionResult> CancelUpliftRequest(int id, int requestId, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                var result = await _portalService.CancelUpliftRequestAsync(session, id, requestId, cancellationToken);
                return Ok(new DataResponse { Status = "Success", Data = result });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The requested action could not be completed for this dispatch") });
            }
        }

        // SH-101: vendor withdraw (canonical) endpoint.
        [HttpPost("dispatches/{id:int}/uplift-request/{requestId:int}/withdraw")]
        public async Task<IActionResult> WithdrawUpliftRequest(int id, int requestId, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                var result = await _portalService.WithdrawUpliftAsync(session, id, requestId, cancellationToken);
                return Ok(new DataResponse { Status = "Success", Data = result });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The requested action could not be completed for this dispatch") });
            }
        }

        // SH-101: vendor revise endpoint on ChangesRequested.
        [HttpPost("dispatches/{id:int}/uplift-request/{requestId:int}/revise")]
        public async Task<IActionResult> ReviseUpliftRequest(int id, int requestId, [FromBody] UpliftRequestBody? body, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                var result = await _portalService.ReviseUpliftAsync(session, id, requestId, body?.RequestedNTE ?? 0m, body?.Reason, body?.EvidenceDocumentId, cancellationToken);
                return Ok(new DataResponse { Status = "Success", Data = result });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The requested action could not be completed for this dispatch") });
            }
        }

        [HttpPost("dispatches/{id:int}/completion-documents")]
        [HttpPost("dispatches/{id:int}/documents")]
        [RequestSizeLimit(10_000_000)]
        public async Task<IActionResult> UploadCompletionDocument(
            int id,
            [FromForm] IFormFile file,
            [FromForm] int? replacesDocumentId = null,
            [FromForm] string? purpose = null,
            CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            try
            {
                var result = await _portalService.UploadCompletionDocumentAsync(
                    session,
                    id,
                    file,
                    replacesDocumentId,
                    purpose,
                    cancellationToken);
                return Ok(new DataResponse { Status = "Success", Data = result });
            }
            catch (KeyNotFoundException)
            {
                return NotFound(new Response { Status = "Error", Message = "Dispatch not found" });
            }
            catch (InvalidOperationException ex)
            {
                return BadRequest(new Response { Status = "Error", Message = _logger.Sanitize(ex, "The completion document could not be uploaded") });
            }
        }

        [HttpGet("dispatches/{id:int}/completion-documents/{documentId:int}")]
        [HttpGet("dispatches/{id:int}/documents/{documentId:int}")]
        public async Task<IActionResult> DownloadCompletionDocument(int id, int documentId, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            var result = await _portalService.DownloadCompletionDocumentAsync(session, id, documentId, cancellationToken);
            return result.Outcome switch
            {
                VendorDocumentDownloadOutcome.Ok => File(result.Content!, result.ContentType!, result.FileName!),
                VendorDocumentDownloadOutcome.Locked => StatusCode(StatusCodes.Status423Locked, new Response { Status = "Locked", Message = "The completion document is not available for download yet." }),
                _ => NotFound(new Response { Status = "Error", Message = "Completion document not found" })
            };
        }

        [HttpGet("dispatches/{id:int}/documents/{documentId:int}/status")]
        public async Task<IActionResult> GetDocumentStatus(int id, int documentId, CancellationToken cancellationToken = default)
        {
            var session = await ResolveSessionAsync(cancellationToken);
            if (session == null) return Unauthorized(new Response { Status = "Error", Message = "Invalid or expired token" });

            var result = await _portalService.GetDocumentStatusAsync(session, id, documentId, cancellationToken);
            return result == null
                ? NotFound(new Response { Status = "Error", Message = "Document not found" })
                : Ok(new DataResponse { Status = "Success", Data = result });
        }

        private async Task<VendorPortalSession?> ResolveSessionAsync(CancellationToken cancellationToken)
        {
            if (!Request.Headers.TryGetValue(TokenHeader, out var values)) return null;
            var token = values.ToString();
            return await _portalService.ResolveSessionAsync(token, cancellationToken);
        }

        public class ChangeStatusRequest
        {
            public string? Status { get; set; }
        }

        public class RequestCancelRequest
        {
            public string? Reason { get; set; }
        }

        public class RefuseRequest
        {
            public string? Reason { get; set; }
        }

        public class ChecklistUpdateRequest
        {
            public bool IsCompleted { get; set; }
        }

        public class SignoffRequest
        {
            public string? Name { get; set; }
            public string? Signature { get; set; }
            public string? SignatureMethod { get; set; }
            public string? SignoffType { get; set; }
        }

        public class CommentRequest
        {
            public string? CommentText { get; set; }
        }

        public class UpliftRequestBody
        {
            public decimal RequestedNTE { get; set; }
            public string? Reason { get; set; }
            // SH-101: client idempotency key and supporting evidence.
            public string? RequestKey { get; set; }
            public int? EvidenceDocumentId { get; set; }
        }
    }
}