import { BadRequestException, ConflictException, Injectable, NotFoundException } from '@nestjs/common';
import { Prisma } from '@prisma/client';
import ExcelJS from 'exceljs';
import { createHash, randomUUID } from 'node:crypto';
import { extname } from 'node:path';
import { FilesService } from '../files/files.service';
import { PrismaService } from '../prisma/prisma.service';
import { SmsConfigService } from '../sms-config/sms-config.service';
import type { AnalyzeImportOptions, CreateImportProfileDto, CreateReportBatchDto, EmbeddedImage, ImportCommitDto, ImportMapping, PagedQuery, ReportBatchInspection, ReportBatchTarget, ReviewImportItemsDto } from './report-materials.contracts';
import { profileData, validateProfile, loadWorkbook, assertSafeWorkbook, safeSpreadsheetText, readEmbeddedImages, suggestMappings, remapProfileColumns, signatureCoreMapping, drainageCoreMapping, normalizeHeader, normalizeFieldCode, clamp, normalizePage, normalizePageSize, dateRange, cellText, transformValue, mappedCoreValue, dynamicValues, jsonRecord, hasValue, isFileRef, resolveExportValue, applyExportTransform, styleHeader, normalizeImageExtension, imageContentType, safeFileName, normalizeBatchIdempotencyKey, jsonStringArray, jsonSafe } from './report-materials.helpers';
import type { ReportBatchGenerationService } from './batch-generation.service';
import { normalizeChannelCarriers } from '../channels/channels.helpers';

/** R4 report-materials domain service composed behind ReportMaterialsService. */
export class ReportChannelExportService {
  constructor(private readonly prisma: PrismaService, private readonly files: FilesService, private readonly smsConfig: SmsConfigService) {}

  async exportChannelBatch(batchId: string, channelId: string, items: Array<Awaited<ReturnType<ReportBatchGenerationService['prepareBatchItem']>>>) {
      const channel = await this.prisma.smsChannel.findUnique({ where: { id: channelId } });
      if (!channel) throw new NotFoundException('通道不存在');
      const reportTypes = [...new Set(items.map((item) => item.reportType))];
      const workbook = new ExcelJS.Workbook();
      const fileRows: Array<{ item: (typeof items)[number]; taskId: string; rowNumber: number }> = [];
      const incompleteBatchItemIds: string[] = [];
      let totalRows = 0;
      for (const reportType of reportTypes) {
        const fields = await this.prisma.channelReportField.findMany({ where: { channelId, status: 'active', reportType: { in: [reportType, 'both'] } }, orderBy: [{ sortOrder: 'asc' }, { createdAt: 'asc' }] });
        const sheet = workbook.addWorksheet(reportType === 'signature' ? '签名报备' : '引流信息报备', { views: [{ state: 'frozen', ySplit: 1 }] });
        sheet.properties.defaultRowHeight = 22;
        sheet.columns = fields.map((field) => ({ header: field.exportName || field.name, key: field.code, width: field.columnWidth }));
        styleHeader(sheet.getRow(1));
        for (const item of items.filter((current) => current.reportType === reportType)) {
          const values = fields.map((field) => resolveExportValue(item.snapshot, field.code, field.name) ?? field.defaultValue ?? '');
          const missing = fields.filter((field, index) => field.required && !hasValue(values[index]));
          const missingReason = fields.length === 0 ? '通道未配置当前资料类型的报备字段' : missing.length ? `缺少字段：${missing.map((field) => field.exportName || field.name).join('、')}` : null;
          const reportCarriers = reportType === 'signature' ? normalizeChannelCarriers(channel.carriers, channel.carrier) : [null];
          const tasks: Array<{ task: { id: string; reason: string | null }; existingTask: { status: string } | null }> = [];
          for (const carrier of reportCarriers) {
            const existingTask = await this.prisma.channelSignatureReportTask.findFirst({ where: { signatureId: item.signature.id, channelId, carrier, reportType, drainageItemId: reportType === 'drainage' ? item.drainageInfo!.id : null } });
            const task = existingTask
              ? await this.prisma.channelSignatureReportTask.update({ where: { id: existingTask.id }, data: { status: missingReason ? 'waiting_material' : 'exporting', reason: missingReason, ...(reportType === 'signature' ? { approvedAt: null } : {}) } })
              : await this.prisma.channelSignatureReportTask.create({ data: { tenantId: item.signature.tenantId, signatureId: item.signature.id, channelId, carrier, approvalScope: reportType === 'signature' ? 'carrier_specific' : 'legacy_channel', reportType, drainageItemId: item.drainageInfo?.id, status: missingReason ? 'waiting_material' : 'exporting', reason: missingReason } });
            tasks.push({ task, existingTask });
          }
          const task = tasks[0].task;
          if (missingReason) {
            incompleteBatchItemIds.push(item.batchItem.id);
            for (const entry of tasks) await this.recordTask(entry.task.id, channelId, entry.existingTask?.status, 'waiting_material', task.reason ?? undefined);
            continue;
          }
          const row = sheet.addRow(values.map((value, index) => isFileRef(value) ? value.fileName : applyExportTransform(value, fields[index]?.transform)));
          totalRows += 1;
          let targetHeight = 22;
          for (const [index, value] of values.entries()) {
            if (!isFileRef(value)) continue;
            const downloaded = await this.files.getDownload(value.fileObjectId);
            if (!downloaded.fileObject.contentType.startsWith('image/')) continue;
            const extension = normalizeImageExtension(extname(downloaded.fileObject.fileName).slice(1) || downloaded.fileObject.contentType.split('/')[1]);
            if (!['png', 'jpeg', 'gif'].includes(extension)) continue;
            const imageId = workbook.addImage({ base64: `data:${downloaded.fileObject.contentType};base64,${downloaded.content.toString('base64')}`, extension: extension as 'png' | 'jpeg' | 'gif' });
            const widthCells = Math.max(0.8, fields[index].imageWidth / Math.max(60, fields[index].columnWidth * 7));
            const heightRows = Math.max(0.8, fields[index].imageHeight / 20);
            sheet.addImage(imageId, { tl: { col: index + 0.08, row: row.number - 1 + 0.08 }, br: { col: index + Math.min(0.95, widthCells), row: row.number - 1 + Math.min(0.95, heightRows) }, editAs: 'oneCell' } as never);
            targetHeight = Math.max(targetHeight, fields[index].imageHeight * 0.75 + 8);
          }
          row.height = targetHeight;
          fileRows.push({ item, taskId: task.id, rowNumber: row.number });
          for (const entry of tasks) await this.recordTask(entry.task.id, channelId, entry.existingTask?.status, 'exporting');
        }
      }
      if (workbook.worksheets.every((sheet) => sheet.rowCount <= 1)) {
        for (const sheet of [...workbook.worksheets]) workbook.removeWorksheet(sheet.id);
        const empty = workbook.addWorksheet('无可导出数据');
        empty.getCell('A1').value = '所选资料缺少当前通道必填字段，请补充后重新生成。';
        empty.getColumn(1).width = 64;
      }
      const buffer = Buffer.from(await workbook.xlsx.writeBuffer());
      const fileName = `${safeFileName(channel.name)}-${batchId.slice(-8)}.xlsx`;
      const uploaded = await this.files.upload({ purpose: 'report_export', prefix: `report-exports/${batchId}` }, { originalname: fileName, mimetype: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet', size: buffer.length, buffer });
      const file = await this.prisma.reportExportFile.create({ data: { batchId, channelId, fileObjectId: uploaded.id, fileName, rowCount: totalRows } });
      if (fileRows.length) await this.prisma.reportExportFileItem.createMany({ data: fileRows.map((entry) => ({ exportFileId: file.id, batchItemId: entry.item.batchItem.id, taskId: entry.taskId, rowNumber: entry.rowNumber })) });
      return { file: { ...file, fileObject: uploaded }, incompleteBatchItemIds };
    }

  recordTask(taskId: string, channelId: string, statusBefore: string | undefined, statusAfter: string, reason?: string) {
      return this.prisma.channelSignatureReportRecord.create({ data: { taskId, channelId, action: 'batch_export', statusBefore, statusAfter, reason, sourceEntry: 'report_task' } });
    }
}