import { Controller, Get, Post, Query, Logger } from '@nestjs/common';
import {
  ApiTags,
  ApiOperation,
  ApiResponse,
  ApiQuery,
  ApiBadRequestResponse,
  ApiInternalServerErrorResponse,
} from '@nestjs/swagger';
import { IcdService } from './icd.service';
import { SearchIcdDto } from './dto/search-icd.dto';
import {
  IcdSearchResponseDto,
  IcdImportResponseDto,
  IcdStatisticsResponseDto,
  ErrorResponseDto,
} from './dto/icd-response.dto';

@ApiTags('ICD')
@Controller('icd')
export class IcdController {
  private readonly logger = new Logger(IcdController.name);

  constructor(private readonly icdService: IcdService) {}

  @Post('import')
  @ApiOperation({
    summary: 'Import ICD data from Excel files',
    description:
      'Import ICD-9 and ICD-10 codes from Excel files located in the test directory. This operation will process both ICD files and insert/update the database with the latest codes.',
  })
  @ApiResponse({
    status: 200,
    description: 'ICD data imported successfully',
    type: IcdImportResponseDto,
  })
  @ApiBadRequestResponse({
    description: 'Bad request - Invalid file format or missing files',
    type: ErrorResponseDto,
  })
  @ApiInternalServerErrorResponse({
    description: 'Internal server error during import process',
    type: ErrorResponseDto,
  })
  async importData(): Promise<IcdImportResponseDto> {
    try {
      this.logger.log('Starting ICD data import...');
      const result = await this.icdService.importIcdData();
      return {
        success: true,
        message: 'ICD data imported successfully',
        data: result,
      };
    } catch (error) {
      this.logger.error('Error importing ICD data:', error);
      throw error;
    }
  }

  @Get('search')
  @ApiOperation({
    summary: 'Search ICD codes with filters and pagination',
    description:
      'Search for ICD codes using various filters like category, search term, with pagination support. Returns a paginated list of matching ICD codes.',
  })
  @ApiQuery({
    name: 'category',
    required: false,
    description: 'Filter by ICD category',
    enum: ['ICD9', 'ICD10'],
    example: 'ICD10',
  })
  @ApiQuery({
    name: 'search',
    required: false,
    description: 'Search term for ICD code or description',
    example: 'diabetes',
  })
  @ApiQuery({
    name: 'page',
    required: false,
    description: 'Page number for pagination',
    example: 1,
    type: 'number',
  })
  @ApiQuery({
    name: 'limit',
    required: false,
    description: 'Number of items per page (max 100)',
    example: 10,
    type: 'number',
  })
  @ApiResponse({
    status: 200,
    description: 'ICD codes retrieved successfully',
    type: IcdSearchResponseDto,
  })
  @ApiBadRequestResponse({
    description: 'Bad request - Invalid query parameters',
    type: ErrorResponseDto,
  })
  @ApiInternalServerErrorResponse({
    description: 'Internal server error during search',
    type: ErrorResponseDto,
  })
  async searchIcdCodes(
    @Query('category') category?: string,
    @Query('search') search?: string,
    @Query('page') page?: string,
    @Query('limit') limit?: string,
  ): Promise<IcdSearchResponseDto> {
    try {
      const pageNum = page ? parseInt(page, 10) : 1;
      const limitNum = limit ? parseInt(limit, 10) : 10;

      const result = await this.icdService.findIcdCodes(
        category,
        search,
        pageNum,
        limitNum,
      );

      return {
        success: true,
        data: result.data,
        pagination: {
          currentPage: result.page,
          totalPages: result.totalPages,
          totalItems: result.total,
          itemsPerPage: result.limit,
          hasNextPage: result.page < result.totalPages,
          hasPreviousPage: result.page > 1,
        },
      };
    } catch (error) {
      this.logger.error('Error searching ICD codes:', error);
      throw error;
    }
  }

  @Get('statistics')
  @ApiOperation({
    summary: 'Get ICD database statistics',
    description:
      'Retrieve statistics about the ICD database including total counts for ICD-9 and ICD-10 codes, and last import information.',
  })
  @ApiResponse({
    status: 200,
    description: 'Statistics retrieved successfully',
    type: IcdStatisticsResponseDto,
  })
  @ApiInternalServerErrorResponse({
    description: 'Internal server error while fetching statistics',
    type: ErrorResponseDto,
  })
  async getStatistics(): Promise<IcdStatisticsResponseDto> {
    try {
      const stats = await this.icdService.getStatistics();
      return {
        success: true,
        data: stats,
      };
    } catch (error) {
      this.logger.error('Error getting statistics:', error);
      throw error;
    }
  }
}