using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using TakeoutSaaS.Application.Dictionary.Models;
using TakeoutSaaS.Application.Dictionary.Services;
using TakeoutSaaS.Domain.Dictionary.Enums;
using TakeoutSaaS.Module.Authorization.Attributes;
using TakeoutSaaS.Shared.Abstractions.Constants;
using TakeoutSaaS.Shared.Abstractions.Results;
using TakeoutSaaS.Shared.Abstractions.Security;
using TakeoutSaaS.Shared.Abstractions.Tenancy;
using TakeoutSaaS.Shared.Web.Api;

namespace TakeoutSaaS.AdminApi.Controllers;

/// <summary>
/// 字典标签覆盖管理。
/// </summary>
[ApiVersion("1.0")]
[Authorize]
[Route("api/admin/v{version:apiVersion}/dictionary/label-overrides")]
public sealed class DictionaryLabelOverridesController(
    DictionaryLabelOverrideService labelOverrideService,
    ITenantProvider tenantProvider,
    ICurrentUserAccessor currentUserAccessor)
    : BaseApiController
{
    private const string TenantIdHeaderName = "X-Tenant-Id";

    #region 租户端 API（租户覆盖系统字典）

    /// <summary>
    /// 获取当前租户的标签覆盖列表。
    /// </summary>
    [HttpGet("tenant")]
    [PermissionAuthorize("dictionary:override:read")]
    [ProducesResponseType(typeof(ApiResponse<IReadOnlyList<LabelOverrideDto>>), StatusCodes.Status200OK)]
    public async Task<ApiResponse<IReadOnlyList<LabelOverrideDto>>> ListTenantOverrides(
        [FromQuery] OverrideType? overrideType,
        CancellationToken cancellationToken)
    {
        var headerError = EnsureTenantHeader<IReadOnlyList<LabelOverrideDto>>();
        if (headerError != null)
        {
            return headerError;
        }

        var tenantId = tenantProvider.GetCurrentTenantId();
        var result = await labelOverrideService.GetOverridesAsync(tenantId, overrideType, cancellationToken);
        return ApiResponse<IReadOnlyList<LabelOverrideDto>>.Ok(result);
    }

    /// <summary>
    /// 租户覆盖系统字典项的标签。
    /// </summary>
    [HttpPost("tenant")]
    [PermissionAuthorize("dictionary:override:update")]
    [ProducesResponseType(typeof(ApiResponse<LabelOverrideDto>), StatusCodes.Status200OK)]
    public async Task<ApiResponse<LabelOverrideDto>> CreateTenantOverride(
        [FromBody] UpsertLabelOverrideRequest request,
        CancellationToken cancellationToken)
    {
        var headerError = EnsureTenantHeader<LabelOverrideDto>();
        if (headerError != null)
        {
            return headerError;
        }

        var tenantId = tenantProvider.GetCurrentTenantId();
        var operatorId = currentUserAccessor.UserId;
        var result = await labelOverrideService.UpsertTenantOverrideAsync(tenantId, request, operatorId, cancellationToken);
        return ApiResponse<LabelOverrideDto>.Ok(result);
    }

    /// <summary>
    /// 租户删除自己的标签覆盖。
    /// </summary>
    [HttpDelete("tenant/{dictionaryItemId:long}")]
    [PermissionAuthorize("dictionary:override:delete")]
    [ProducesResponseType(typeof(ApiResponse<object>), StatusCodes.Status200OK)]
    [ProducesResponseType(typeof(ApiResponse<object>), StatusCodes.Status404NotFound)]
    public async Task<ApiResponse<object>> DeleteTenantOverride(long dictionaryItemId, CancellationToken cancellationToken)
    {
        var headerError = EnsureTenantHeader<object>();
        if (headerError != null)
        {
            return headerError;
        }

        var tenantId = tenantProvider.GetCurrentTenantId();
        var operatorId = currentUserAccessor.UserId;
        var success = await labelOverrideService.DeleteOverrideAsync(
            tenantId,
            dictionaryItemId,
            operatorId,
            allowPlatformEnforcement: false,
            cancellationToken);
        return success
            ? ApiResponse.Success()
            : ApiResponse.Error(ErrorCodes.NotFound, "覆盖配置不存在");
    }

    #endregion

    #region 平台端 API（平台管理所有租户的覆盖）

    /// <summary>
    /// 获取指定租户的所有标签覆盖（平台管理员用）。
    /// </summary>
    [HttpGet("platform/{targetTenantId:long}")]
    [PermissionAuthorize("dictionary:override:platform:read")]
    [ProducesResponseType(typeof(ApiResponse<IReadOnlyList<LabelOverrideDto>>), StatusCodes.Status200OK)]
    public async Task<ApiResponse<IReadOnlyList<LabelOverrideDto>>> ListPlatformOverrides(
        long targetTenantId,
        [FromQuery] OverrideType? overrideType,
        CancellationToken cancellationToken)
    {
        var result = await labelOverrideService.GetOverridesAsync(targetTenantId, overrideType, cancellationToken);
        return ApiResponse<IReadOnlyList<LabelOverrideDto>>.Ok(result);
    }

    /// <summary>
    /// 平台强制覆盖租户字典项的标签。
    /// </summary>
    [HttpPost("platform/{targetTenantId:long}")]
    [PermissionAuthorize("dictionary:override:platform:update")]
    [ProducesResponseType(typeof(ApiResponse<LabelOverrideDto>), StatusCodes.Status200OK)]
    public async Task<ApiResponse<LabelOverrideDto>> CreatePlatformOverride(
        long targetTenantId,
        [FromBody] UpsertLabelOverrideRequest request,
        CancellationToken cancellationToken)
    {
        var operatorId = currentUserAccessor.UserId;
        var result = await labelOverrideService.UpsertPlatformOverrideAsync(targetTenantId, request, operatorId, cancellationToken);
        return ApiResponse<LabelOverrideDto>.Ok(result);
    }

    /// <summary>
    /// 平台删除对租户的强制覆盖。
    /// </summary>
    [HttpDelete("platform/{targetTenantId:long}/{dictionaryItemId:long}")]
    [PermissionAuthorize("dictionary:override:platform:delete")]
    [ProducesResponseType(typeof(ApiResponse<object>), StatusCodes.Status200OK)]
    [ProducesResponseType(typeof(ApiResponse<object>), StatusCodes.Status404NotFound)]
    public async Task<ApiResponse<object>> DeletePlatformOverride(
        long targetTenantId,
        long dictionaryItemId,
        CancellationToken cancellationToken)
    {
        var operatorId = currentUserAccessor.UserId;
        var success = await labelOverrideService.DeleteOverrideAsync(
            targetTenantId,
            dictionaryItemId,
            operatorId,
            cancellationToken: cancellationToken);
        return success
            ? ApiResponse.Success()
            : ApiResponse.Error(ErrorCodes.NotFound, "覆盖配置不存在");
    }

    #endregion

    private ApiResponse<T>? EnsureTenantHeader<T>()
    {
        if (!Request.Headers.TryGetValue(TenantIdHeaderName, out var tenantHeader) || string.IsNullOrWhiteSpace(tenantHeader))
        {
            return ApiResponse<T>.Error(StatusCodes.Status400BadRequest, $"缺少租户标识，请在请求头 {TenantIdHeaderName} 指定租户");
        }

        if (!long.TryParse(tenantHeader.FirstOrDefault(), out _))
        {
            return ApiResponse<T>.Error(StatusCodes.Status400BadRequest, $"租户标识无效，请在请求头 {TenantIdHeaderName} 指定正确的租户 ID");
        }

        return null;
    }
}