namespace WebApi.Controllers;

[ApiController]
[Route("api/[controller]/[action]")]
public class TransactionCategoryController(
    ITransactionCategoryRepository categoryRepository,
    ILogger<TransactionCategoryController> logger
) : ControllerBase
{
    /// <summary>
    /// 获取分类树（支持按类型筛选）
    /// </summary>
    [HttpGet]
    public async Task<BaseResponse<List<TransactionCategoryTreeDto>>> GetTreeAsync([FromQuery] TransactionType? type = null)
    {
        try
        {
            var tree = await categoryRepository.GetCategoryTreeAsync(type);
            return new BaseResponse<List<TransactionCategoryTreeDto>>
            {
                Success = true,
                Data = tree
            };
        }
        catch (Exception ex)
        {
            logger.LogError(ex, "获取分类树失败");
            return BaseResponse<List<TransactionCategoryTreeDto>>.Fail($"获取分类树失败: {ex.Message}");
        }
    }

    /// <summary>
    /// 获取顶级分类列表（按类型）
    /// </summary>
    [HttpGet]
    public async Task<BaseResponse<List<TransactionCategory>>> GetTopLevelAsync([FromQuery] TransactionType type)
    {
        try
        {
            var categories = await categoryRepository.GetTopLevelCategoriesByTypeAsync(type);
            return new BaseResponse<List<TransactionCategory>>
            {
                Success = true,
                Data = categories
            };
        }
        catch (Exception ex)
        {
            logger.LogError(ex, "获取顶级分类失败, Type: {Type}", type);
            return BaseResponse<List<TransactionCategory>>.Fail($"获取顶级分类失败: {ex.Message}");
        }
    }

    /// <summary>
    /// 获取子分类列表
    /// </summary>
    [HttpGet]
    public async Task<BaseResponse<List<TransactionCategory>>> GetChildrenAsync([FromQuery] long parentId)
    {
        try
        {
            var categories = await categoryRepository.GetChildCategoriesAsync(parentId);
            return new BaseResponse<List<TransactionCategory>>
            {
                Success = true,
                Data = categories
            };
        }
        catch (Exception ex)
        {
            logger.LogError(ex, "获取子分类失败, ParentId: {ParentId}", parentId);
            return BaseResponse<List<TransactionCategory>>.Fail($"获取子分类失败: {ex.Message}");
        }
    }

    /// <summary>
    /// 根据ID获取分类详情
    /// </summary>
    [HttpGet("{id}")]
    public async Task<BaseResponse<TransactionCategory>> GetByIdAsync(long id)
    {
        try
        {
            var category = await categoryRepository.GetByIdAsync(id);
            if (category == null)
            {
                return BaseResponse<TransactionCategory>.Fail("分类不存在");
            }

            return new BaseResponse<TransactionCategory>
            {
                Success = true,
                Data = category
            };
        }
        catch (Exception ex)
        {
            logger.LogError(ex, "获取分类详情失败, Id: {Id}", id);
            return BaseResponse<TransactionCategory>.Fail($"获取分类详情失败: {ex.Message}");
        }
    }

    /// <summary>
    /// 创建分类
    /// </summary>
    [HttpPost]
    public async Task<BaseResponse<long>> CreateAsync([FromBody] CreateCategoryDto dto)
    {
        try
        {
            // 检查同名分类
            var existing = await categoryRepository.GetByNameAndParentAsync(dto.Name, dto.ParentId, dto.Type);
            if (existing != null)
            {
                return BaseResponse<long>.Fail("同级已存在相同名称的分类");
            }

            var category = new TransactionCategory
            {
                Name = dto.Name,
                ParentId = dto.ParentId,
                Type = dto.Type,
                Level = dto.Level,
                SortOrder = dto.SortOrder,
                Icon = dto.Icon,
                Remark = dto.Remark
            };

            var result = await categoryRepository.AddAsync(category);
            if (result)
            {
                return new BaseResponse<long>
                {
                    Success = true,
                    Data = category.Id
                };
            }
            else
            {
                return BaseResponse<long>.Fail("创建分类失败");
            }
        }
        catch (Exception ex)
        {
            logger.LogError(ex, "创建分类失败, Dto: {@Dto}", dto);
            return BaseResponse<long>.Fail($"创建分类失败: {ex.Message}");
        }
    }

    /// <summary>
    /// 更新分类
    /// </summary>
    [HttpPost]
    public async Task<BaseResponse> UpdateAsync([FromBody] UpdateCategoryDto dto)
    {
        try
        {
            var category = await categoryRepository.GetByIdAsync(dto.Id);
            if (category == null)
            {
                return BaseResponse.Fail("分类不存在");
            }

            // 如果修改了名称，检查同名
            if (category.Name != dto.Name)
            {
                var existing = await categoryRepository.GetByNameAndParentAsync(dto.Name, category.ParentId, category.Type);
                if (existing != null && existing.Id != dto.Id)
                {
                    return BaseResponse.Fail("同级已存在相同名称的分类");
                }
            }

            category.Name = dto.Name;
            category.SortOrder = dto.SortOrder;
            category.Icon = dto.Icon;
            category.IsEnabled = dto.IsEnabled;
            category.Remark = dto.Remark;
            category.UpdateTime = DateTime.Now;

            var success = await categoryRepository.UpdateAsync(category);
            if (success)
            {
                return new BaseResponse { Success = true };
            }
            else
            {
                return BaseResponse.Fail("更新分类失败");
            }
        }
        catch (Exception ex)
        {
            logger.LogError(ex, "更新分类失败, Dto: {@Dto}", dto);
            return BaseResponse.Fail($"更新分类失败: {ex.Message}");
        }
    }

    /// <summary>
    /// 删除分类
    /// </summary>
    [HttpPost]
    public async Task<BaseResponse> DeleteAsync([FromQuery] long id)
    {
        try
        {
            // 检查是否有子分类
            var children = await categoryRepository.GetChildCategoriesAsync(id);
            if (children.Any())
            {
                return BaseResponse.Fail("该分类下存在子分类，无法删除");
            }

            // 检查是否被使用
            var inUse = await categoryRepository.IsCategoryInUseAsync(id);
            if (inUse)
            {
                return BaseResponse.Fail("该分类已被使用，无法删除");
            }

            var success = await categoryRepository.DeleteAsync(id);
            if (success)
            {
                return new BaseResponse { Success = true };
            }
            else
            {
                return BaseResponse.Fail("删除分类失败，分类不存在");
            }
        }
        catch (Exception ex)
        {
            logger.LogError(ex, "删除分类失败, Id: {Id}", id);
            return BaseResponse.Fail($"删除分类失败: {ex.Message}");
        }
    }

    /// <summary>
    /// 批量创建分类（用于初始化）
    /// </summary>
    [HttpPost]
    public async Task<BaseResponse<int>> BatchCreateAsync([FromBody] List<CreateCategoryDto> dtoList)
    {
        try
        {
            var categories = dtoList.Select(dto => new TransactionCategory
            {
                Name = dto.Name,
                ParentId = dto.ParentId,
                Type = dto.Type,
                Level = dto.Level,
                SortOrder = dto.SortOrder,
                Icon = dto.Icon,
                Remark = dto.Remark
            }).ToList();

            var result = await categoryRepository.AddRangeAsync(categories);
            if (result)
            {
                return new BaseResponse<int>
                {
                    Success = true,
                    Data = categories.Count
                };
            }
            else
            {
                return BaseResponse<int>.Fail("批量创建分类失败");
            }
        }
        catch (Exception ex)
        {
            logger.LogError(ex, "批量创建分类失败, Count: {Count}", dtoList.Count);
            return BaseResponse<int>.Fail($"批量创建分类失败: {ex.Message}");
        }
    }
}

/// <summary>
/// 创建分类DTO
/// </summary>
public record CreateCategoryDto(
    string Name,
    long ParentId,
    TransactionType Type,
    int Level,
    int SortOrder = 0,
    string? Icon = null,
    string? Remark = null
);

/// <summary>
/// 更新分类DTO
/// </summary>
public record UpdateCategoryDto(
    long Id,
    string Name,
    int SortOrder,
    string? Icon,
    bool IsEnabled,
    string? Remark
);