using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Kurs.Platform.DeveloperKit;
using Kurs.Platform.Entities;
using Microsoft.EntityFrameworkCore;
using Volo.Abp.Application.Dtos;
using Volo.Abp.Application.Services;
using Volo.Abp.Domain.Repositories;

namespace Platform.Api.Application;

public class CrudEndpointGenerateAppService : CrudAppService<
    CrudEndpoint,
    CrudEndpointDto,
    Guid,
    PagedAndSortedResultRequestDto,
    CreateUpdateCrudEndpointDto>, ICrudEndpointAppService
{
    private readonly IRepository<CustomEntity, Guid> _entityRepository;
    private readonly IRepository<CrudMigration, Guid> _migrationRepository;
    private readonly IRepository<CrudEndpoint, Guid> _endpointRepository;

    public CrudEndpointGenerateAppService(
        IRepository<CrudEndpoint, Guid> repository,
        IRepository<CustomEntity, Guid> entityRepository,
        IRepository<CrudMigration, Guid> migrationRepository,
        IRepository<CrudEndpoint, Guid> endpointRepository)
    : base(repository)
    {
        _entityRepository = entityRepository;
        _migrationRepository = migrationRepository;
        _endpointRepository = endpointRepository;
    }

    public virtual async Task<List<CrudEndpointDto>> GetActiveEndpointsAsync()
    {
        var endpoints = await Repository.GetListAsync(x => x.IsActive);
        return await MapToGetListOutputDtosAsync(endpoints);
    }

    public virtual async Task<List<CrudEndpointDto>> GetEndpointsByEntityAsync(Guid entityId)
    {
        var endpoints = await _endpointRepository.GetListAsync(x => x.EntityId == entityId);
        return ObjectMapper.Map<List<CrudEndpoint>, List<CrudEndpointDto>>(endpoints);
    }

    public virtual async Task<PagedResultDto<CrudEndpointDto>> GenerateCrudEndpointsAsync(Guid entityId)
    {
        // Entity + Fields
        var entityQueryable = await _entityRepository.GetQueryableAsync();
        var entity = await entityQueryable
            .Include(x => x.Fields)
            .FirstOrDefaultAsync(x => x.Id == entityId);

        if (entity == null)
        {
            throw new Exception($"Entity with ID {entityId} not found");
        }

        // Migration kontrolü
        var migrationQueryable = await _migrationRepository.GetQueryableAsync();
        var migration = await migrationQueryable
            .Where(x => x.EntityId == entityId && x.Status == "applied")
            .FirstOrDefaultAsync();

        if (migration == null)
        {
            throw new Exception($"No applied migration found for entity {entity.Name}. Please apply migration first.");
        }

        // CRUD endpointleri oluştur
        var endpoints = new List<CrudEndpoint>();
        var entityName = entity.Name;
        var entityDisplayName = entity.DisplayName;

        endpoints.Add(new CrudEndpoint
        {
            EntityId = entityId,
            EntityName = entityName,
            Method = "GET",
            Path = $"/api/app/crudendpoint/{entityName.ToLower()}",
            OperationType = "GetList",
            IsActive = true,
            CsharpCode = GenerateGetAllCode(entityName, entityDisplayName)
        });

        endpoints.Add(new CrudEndpoint
        {
            EntityId = entityId,
            EntityName = entityName,
            Method = "GET",
            Path = $"/api/app/crudendpoint/{entityName.ToLower()}/{{id}}",
            OperationType = "GetById",
            IsActive = true,
            CsharpCode = GenerateGetByIdCode(entityName, entityDisplayName)
        });

        endpoints.Add(new CrudEndpoint
        {
            EntityId = entityId,
            EntityName = entityName,
            Method = "POST",
            Path = $"/api/app/crudendpoint/{entityName.ToLower()}",
            OperationType = "Create",
            IsActive = true,
            CsharpCode = GenerateCreateCode(entityName, entityDisplayName)
        });

        endpoints.Add(new CrudEndpoint
        {
            EntityId = entityId,
            EntityName = entityName,
            Method = "PUT",
            Path = $"/api/app/crudendpoint/{entityName.ToLower()}/{{id}}",
            OperationType = "Update",
            IsActive = true,
            CsharpCode = GenerateUpdateCode(entityName, entityDisplayName)
        });

        endpoints.Add(new CrudEndpoint
        {
            EntityId = entityId,
            EntityName = entityName,
            Method = "DELETE",
            Path = $"/api/app/crudendpoint/{entityName.ToLower()}/{{id}}",
            OperationType = "Delete",
            IsActive = true,
            CsharpCode = GenerateDeleteCode(entityName, entityDisplayName)
        });

        // Var olanları sil
        var existingEndpoints = await _endpointRepository
            .GetListAsync(x => x.EntityId == entityId);

        await _endpointRepository.DeleteManyAsync(existingEndpoints);

        // Yeni endpointleri ekle
        await _endpointRepository.InsertManyAsync(endpoints, autoSave: true);

        // Entity endpoint durumu güncelle
        entity.EndpointStatus = "applied";
        await _entityRepository.UpdateAsync(entity, autoSave: true);

        var result = ObjectMapper.Map<List<CrudEndpoint>, List<CrudEndpointDto>>(endpoints);

        return new PagedResultDto<CrudEndpointDto>
        {
            Items = result,
            TotalCount = result.Count
        };
    }

    private string GenerateGetAllCode(string entityName, string displayName)
    {
        return $@"[HttpGet]
public async Task<ActionResult<List<{entityName}>>> GetAll{entityName}sAsync()
{{
    var entities = await _context.{entityName}s.ToListAsync();
    return Ok(entities);
}}";
    }

    private string GenerateGetByIdCode(string entityName, string displayName)
    {
        return $@"[HttpGet(""{{id}}"")]
public async Task<ActionResult<{entityName}>> Get{entityName}Async(Guid id)
{{
    var entity = await _context.{entityName}s.FindAsync(id);
    if (entity == null)
    {{
        return NotFound($""{displayName} with ID {{id}} not found"");
    }}
    return Ok(entity);
}}";
    }

    private string GenerateCreateCode(string entityName, string displayName)
    {
        return $@"[HttpPost]
public async Task<ActionResult<{entityName}>> Create{entityName}Async({entityName} {entityName.ToLower()})
{{
    _context.{entityName}s.Add({entityName.ToLower()});
    await _context.SaveChangesAsync();
    return CreatedAtAction(nameof(Get{entityName}Async), new {{ id = {entityName.ToLower()}.Id }}, {entityName.ToLower()});
}}";
    }

    private string GenerateUpdateCode(string entityName, string displayName)
    {
        return $@"[HttpPut(""{{id}}"")]
public async Task<IActionResult> Update{entityName}Async(Guid id, {entityName} {entityName.ToLower()})
{{
    if (id != {entityName.ToLower()}.Id)
    {{
        return BadRequest(""ID mismatch"");
    }}

    _context.Entry({entityName.ToLower()}).State = EntityState.Modified;

    try
    {{
        await _context.SaveChangesAsync();
    }}
    catch (DbUpdateConcurrencyException)
    {{
        if (!await {entityName}ExistsAsync(id))
        {{
            return NotFound($""{displayName} with ID {{id}} not found"");
        }}
        throw;
    }}

    return NoContent();
}}";
    }

    private string GenerateDeleteCode(string entityName, string displayName)
    {
        return $@"[HttpDelete(""{{id}}"")]
public async Task<IActionResult> Delete{entityName}Async(Guid id)
{{
    var {entityName.ToLower()} = await _context.{entityName}s.FindAsync(id);
    if ({entityName.ToLower()} == null)
    {{
        return NotFound($""{displayName} with ID {{id}} not found"");
    }}

    _context.{entityName}s.Remove({entityName.ToLower()});
    await _context.SaveChangesAsync();

    return NoContent();
}}

private async Task<bool> {entityName}ExistsAsync(Guid id)
{{
    return await _context.{entityName}s.AnyAsync(e => e.Id == id);
}}";
    }
}