import {
  BadRequestException,
  Injectable,
  NotFoundException,
} from '@nestjs/common';
import { Cron } from '@nestjs/schedule';
import type {
  AddSmsCampaignRecipientsRequest,
  CreateSmsCampaignRequest,
  SmsCampaignClickerDto,
  SmsCampaignDto,
  SmsCampaignListResponse,
  SmsCampaignReportDto,
  SmsCampaignStatus,
} from '@mento/shared';
import { SMS_CAMPAIGN_CHUNK_SIZE } from '@mento/shared';
import { PrismaService } from '../prisma/prisma.service';
import { SmsService } from '../common/sms.service';
import { renderSmsText } from '../common/sms-text';
import {
  type Actor,
  elevated,
  forScope,
  ownerWhere,
} from '../common/record-scope';
import { TrackingService } from '../tracking/tracking.service';
import { OutboundSmsLogService } from '../outbound-sms/outbound-sms-log.service';
import type { Prisma } from '@prisma/client';

function leadAccessWhere(baseActor: Actor): Prisma.LeadWhereInput {
  const actor = forScope(baseActor, 'leads');
  if (elevated(actor.role)) return {};
  if (actor.dataVisibility === 'org') return {};
  if (
    actor.dataVisibility === 'team' &&
    actor.visibleUserIds &&
    actor.visibleUserIds.length
  ) {
    return { assigneeId: { in: actor.visibleUserIds } };
  }
  return { assigneeId: actor.userId };
}

@Injectable()
export class SmsCampaignsService {
  constructor(
    private readonly prisma: PrismaService,
    private readonly sms: SmsService,
    private readonly tracking: TrackingService,
    private readonly outboundSms: OutboundSmsLogService,
  ) {}

  async list(
    organizationId: string,
    page = 1,
    limit = 20,
  ): Promise<SmsCampaignListResponse> {
    const where = { organizationId };
    const [total, rows] = await Promise.all([
      this.prisma.smsCampaign.count({ where }),
      this.prisma.smsCampaign.findMany({
        where,
        orderBy: { createdAt: 'desc' },
        skip: (page - 1) * limit,
        take: limit,
      }),
    ]);
    return {
      total,
      items: rows.map((row) => this.toDto(row)),
    };
  }

  async get(organizationId: string, id: string): Promise<SmsCampaignDto> {
    const row = await this.prisma.smsCampaign.findFirst({
      where: { id, organizationId },
    });
    if (!row) throw new NotFoundException('کمپین پیدا نشد');
    return this.toDto(row);
  }

  async report(
    organizationId: string,
    id: string,
  ): Promise<SmsCampaignReportDto> {
    const campaign = await this.prisma.smsCampaign.findFirst({
      where: { id, organizationId },
    });
    if (!campaign) throw new NotFoundException('کمپین پیدا نشد');

    const links = await this.prisma.trackingLink.findMany({
      where: {
        organizationId,
        sourceType: 'sms_campaign',
        sourceId: id,
        clickCount: { gt: 0 },
      },
      select: {
        personId: true,
        leadId: true,
        clickCount: true,
        firstClickedAt: true,
        lastClickedAt: true,
      },
    });

    type Agg = {
      personId: string | null;
      leadId: string | null;
      clickCount: number;
      firstClickedAt: Date | null;
      lastClickedAt: Date | null;
    };
    const byContact = new Map<string, Agg>();
    let totalClicks = 0;
    for (const link of links) {
      totalClicks += link.clickCount;
      const key = link.personId
        ? `person:${link.personId}`
        : link.leadId
          ? `lead:${link.leadId}`
          : null;
      if (!key) continue;
      const prev = byContact.get(key);
      if (!prev) {
        byContact.set(key, {
          personId: link.personId,
          leadId: link.leadId,
          clickCount: link.clickCount,
          firstClickedAt: link.firstClickedAt,
          lastClickedAt: link.lastClickedAt,
        });
        continue;
      }
      prev.clickCount += link.clickCount;
      if (
        link.firstClickedAt &&
        (!prev.firstClickedAt || link.firstClickedAt < prev.firstClickedAt)
      ) {
        prev.firstClickedAt = link.firstClickedAt;
      }
      if (
        link.lastClickedAt &&
        (!prev.lastClickedAt || link.lastClickedAt > prev.lastClickedAt)
      ) {
        prev.lastClickedAt = link.lastClickedAt;
      }
    }

    const personIds = [...byContact.values()]
      .map((c) => c.personId)
      .filter((x): x is string => Boolean(x));
    const leadIds = [...byContact.values()]
      .map((c) => c.leadId)
      .filter((x): x is string => Boolean(x));

    const [people, leads, recipients] = await Promise.all([
      personIds.length
        ? this.prisma.person.findMany({
            where: { id: { in: personIds }, organizationId },
            select: { id: true, firstName: true, lastName: true, mobile: true },
          })
        : Promise.resolve([]),
      leadIds.length
        ? this.prisma.lead.findMany({
            where: { id: { in: leadIds }, organizationId },
            select: { id: true, title: true, contactName: true, mobile: true },
          })
        : Promise.resolve([]),
      this.prisma.smsCampaignRecipient.findMany({
        where: { campaignId: id },
        select: { personId: true, leadId: true, mobile: true },
      }),
    ]);

    const personMap = new Map(people.map((p) => [p.id, p]));
    const leadMap = new Map(leads.map((l) => [l.id, l]));
    const mobileByPerson = new Map(
      recipients
        .filter((r) => r.personId)
        .map((r) => [r.personId!, r.mobile ?? ''] as const),
    );
    const mobileByLead = new Map(
      recipients
        .filter((r) => r.leadId)
        .map((r) => [r.leadId!, r.mobile ?? ''] as const),
    );

    const clickedUsers: SmsCampaignClickerDto[] = [...byContact.values()]
      .flatMap((agg): SmsCampaignClickerDto[] => {
        if (agg.personId) {
          const p = personMap.get(agg.personId);
          const name = p
            ? `${p.firstName} ${p.lastName}`.trim()
            : 'مخاطب';
          return [
            {
              contactType: 'customer',
              personId: agg.personId,
              leadId: null,
              name,
              mobile: p?.mobile || mobileByPerson.get(agg.personId) || null,
              firstClickedAt: agg.firstClickedAt?.toISOString() ?? null,
              lastClickedAt: agg.lastClickedAt?.toISOString() ?? null,
              clickCount: agg.clickCount,
            },
          ];
        }
        if (agg.leadId) {
          const l = leadMap.get(agg.leadId);
          return [
            {
              contactType: 'lead',
              personId: null,
              leadId: agg.leadId,
              name: l?.contactName || l?.title || 'سرنخ',
              mobile: l?.mobile || mobileByLead.get(agg.leadId) || null,
              firstClickedAt: agg.firstClickedAt?.toISOString() ?? null,
              lastClickedAt: agg.lastClickedAt?.toISOString() ?? null,
              clickCount: agg.clickCount,
            },
          ];
        }
        return [];
      })
      .sort((a, b) => b.clickCount - a.clickCount);

    const uniqueClickers = clickedUsers.length;
    const sent = campaign.sentCount;
    const clickRate =
      sent > 0 ? Math.round((uniqueClickers / sent) * 10000) / 100 : 0;

    return {
      campaign: this.toDto(campaign),
      totalCount: campaign.totalCount,
      sentCount: campaign.sentCount,
      failedCount: campaign.failedCount,
      skippedCount: campaign.skippedCount,
      uniqueClickers,
      totalClicks,
      clickRate,
      multiClickers: clickedUsers.filter((u) => u.clickCount > 1).length,
      clickedUsers,
    };
  }

  async create(
    actor: Actor,
    dto: CreateSmsCampaignRequest,
  ): Promise<SmsCampaignDto> {
    const name = dto.name?.trim();
    const body = dto.body?.trim();
    if (!name) throw new BadRequestException('نام کمپین الزامی است');
    if (!body || body.length < 2) {
      throw new BadRequestException('متن پیامک کوتاه است');
    }
    const personIds = [...new Set((dto.personIds ?? []).filter(Boolean))];
    const leadIds = [...new Set((dto.leadIds ?? []).filter(Boolean))];
    if (personIds.length && leadIds.length) {
      throw new BadRequestException('کمپین نمی‌تواند همزمان شخص و لید داشته باشد.');
    }
    if (!personIds.length && !leadIds.length) {
      throw new BadRequestException('حداقل یک مخاطب انتخاب کنید');
    }
    if (personIds.length > SMS_CAMPAIGN_CHUNK_SIZE || leadIds.length > SMS_CAMPAIGN_CHUNK_SIZE) {
      throw new BadRequestException(
        `حداکثر ${SMS_CAMPAIGN_CHUNK_SIZE} مخاطب در هر درخواست مجاز است.`,
      );
    }

    const recipients =
      personIds.length > 0
        ? await this.resolvePersonRecipients(actor, personIds)
        : await this.resolveLeadRecipients(actor, leadIds);
    if (!recipients.length) throw new BadRequestException('مخاطب معتبری پیدا نشد');

    const queueNow = Boolean(dto.queueNow);
    const scheduledAt = dto.scheduledAt ? new Date(dto.scheduledAt) : null;
    if (scheduledAt && Number.isNaN(scheduledAt.getTime())) {
      throw new BadRequestException('زمان‌بندی نامعتبر است');
    }

    const status: SmsCampaignStatus =
      queueNow || scheduledAt ? 'queued' : 'draft';
    const skipped = recipients.filter((r) => !r.mobile).length;

    const campaign = await this.prisma.smsCampaign.create({
      data: {
        organizationId: actor.organizationId,
        name,
        body,
        status,
        scheduledAt: queueNow ? new Date() : scheduledAt,
        totalCount: recipients.length,
        skippedCount: skipped,
        createdById: actor.userId,
        recipients: {
          create: recipients.map((r) => ({
            personId: r.personId,
            leadId: r.leadId,
            mobile: r.mobile,
            status: r.mobile ? 'pending' : 'skipped',
          })),
        },
      },
    });

    return this.get(actor.organizationId, campaign.id);
  }

  async addRecipients(
    actor: Actor,
    campaignId: string,
    dto: AddSmsCampaignRecipientsRequest,
  ): Promise<SmsCampaignDto> {
    const campaign = await this.prisma.smsCampaign.findFirst({
      where: { id: campaignId, organizationId: actor.organizationId },
    });
    if (!campaign) throw new NotFoundException('کمپین پیدا نشد');
    if (campaign.status !== 'draft' && campaign.status !== 'cancelled') {
      throw new BadRequestException('فقط به کمپین پیش‌نویس می‌توان مخاطب افزود.');
    }

    const personIds = [...new Set((dto.personIds ?? []).filter(Boolean))];
    const leadIds = [...new Set((dto.leadIds ?? []).filter(Boolean))];
    if (personIds.length && leadIds.length) {
      throw new BadRequestException('در هر درخواست فقط شخص یا فقط لید بفرستید.');
    }
    if (!personIds.length && !leadIds.length) {
      throw new BadRequestException('حداقل یک مخاطب انتخاب کنید');
    }
    if (personIds.length > SMS_CAMPAIGN_CHUNK_SIZE || leadIds.length > SMS_CAMPAIGN_CHUNK_SIZE) {
      throw new BadRequestException(
        `حداکثر ${SMS_CAMPAIGN_CHUNK_SIZE} مخاطب در هر درخواست مجاز است.`,
      );
    }

    const existingSample = await this.prisma.smsCampaignRecipient.findFirst({
      where: { campaignId },
      select: { personId: true, leadId: true },
    });
    if (existingSample?.personId && leadIds.length) {
      throw new BadRequestException('این کمپین فقط برای اشخاص است.');
    }
    if (existingSample?.leadId && personIds.length) {
      throw new BadRequestException('این کمپین فقط برای لیدها است.');
    }

    const resolved =
      personIds.length > 0
        ? await this.resolvePersonRecipients(actor, personIds)
        : await this.resolveLeadRecipients(actor, leadIds);

    const existingIds = new Set(
      (
        await this.prisma.smsCampaignRecipient.findMany({
          where: { campaignId },
          select: { personId: true, leadId: true },
        })
      ).map((r) => r.personId ?? r.leadId ?? ''),
    );
    const fresh = resolved.filter(
      (r) => !existingIds.has(r.personId ?? r.leadId ?? ''),
    );
    if (!fresh.length) {
      return this.get(actor.organizationId, campaignId);
    }

    const skipped = fresh.filter((r) => !r.mobile).length;
    await this.prisma.smsCampaignRecipient.createMany({
      data: fresh.map((r) => ({
        campaignId,
        personId: r.personId,
        leadId: r.leadId,
        mobile: r.mobile,
        status: r.mobile ? 'pending' : 'skipped',
      })),
    });
    await this.prisma.smsCampaign.update({
      where: { id: campaignId },
      data: {
        totalCount: { increment: fresh.length },
        skippedCount: { increment: skipped },
        status: 'draft',
      },
    });
    return this.get(actor.organizationId, campaignId);
  }

  private async resolvePersonRecipients(
    actor: Actor,
    personIds: string[],
  ): Promise<
    Array<{ personId: string; leadId: null; mobile: string | null }>
  > {
    const people = await this.prisma.person.findMany({
      where: {
        id: { in: personIds },
        organizationId: actor.organizationId,
        ...ownerWhere(actor),
      },
      select: { id: true, mobile: true },
    });
    return people.map((p) => ({
      personId: p.id,
      leadId: null,
      mobile: p.mobile?.trim() || null,
    }));
  }

  private async resolveLeadRecipients(
    actor: Actor,
    leadIds: string[],
  ): Promise<
    Array<{ personId: null; leadId: string; mobile: string | null }>
  > {
    const leads = await this.prisma.lead.findMany({
      where: {
        id: { in: leadIds },
        organizationId: actor.organizationId,
        archivedAt: null,
        ...leadAccessWhere(actor),
      },
      select: { id: true, mobile: true },
    });
    return leads.map((l) => ({
      personId: null,
      leadId: l.id,
      mobile: l.mobile?.trim() || null,
    }));
  }

  async queue(organizationId: string, id: string): Promise<SmsCampaignDto> {
    const row = await this.prisma.smsCampaign.findFirst({
      where: { id, organizationId },
    });
    if (!row) throw new NotFoundException('کمپین پیدا نشد');
    if (row.status !== 'draft' && row.status !== 'cancelled') {
      throw new BadRequestException('این کمپین قابل صف‌بندی نیست');
    }
    await this.prisma.smsCampaign.update({
      where: { id },
      data: {
        status: 'queued',
        scheduledAt: row.scheduledAt ?? new Date(),
      },
    });
    return this.get(organizationId, id);
  }

  async cancel(organizationId: string, id: string): Promise<SmsCampaignDto> {
    const row = await this.prisma.smsCampaign.findFirst({
      where: { id, organizationId },
    });
    if (!row) throw new NotFoundException('کمپین پیدا نشد');
    if (row.status === 'done') {
      throw new BadRequestException('کمپین تمام‌شده قابل لغو نیست');
    }
    await this.prisma.smsCampaign.update({
      where: { id },
      data: { status: 'cancelled' },
    });
    return this.get(organizationId, id);
  }

  @Cron('*/1 * * * *')
  async processDue(): Promise<number> {
    if (!this.sms.isConfigured()) return 0;
    const now = new Date();
    const campaigns = await this.prisma.smsCampaign.findMany({
      where: {
        status: 'queued',
        OR: [{ scheduledAt: null }, { scheduledAt: { lte: now } }],
      },
      orderBy: { createdAt: 'asc' },
      take: 3,
    });

    let processed = 0;
    for (const campaign of campaigns) {
      await this.processCampaign(campaign.id);
      processed += 1;
    }
    return processed;
  }

  private async processCampaign(campaignId: string): Promise<void> {
    await this.prisma.smsCampaign.update({
      where: { id: campaignId },
      data: { status: 'sending' },
    });

    const campaign = await this.prisma.smsCampaign.findUnique({
      where: { id: campaignId },
    });
    if (!campaign) return;

    const batch = await this.prisma.smsCampaignRecipient.findMany({
      where: { campaignId, status: 'pending' },
      take: SMS_CAMPAIGN_CHUNK_SIZE,
      orderBy: { createdAt: 'asc' },
    });

    const personIds = batch
      .map((r) => r.personId)
      .filter((id): id is string => Boolean(id));
    const leadIds = batch
      .map((r) => r.leadId)
      .filter((id): id is string => Boolean(id));
    const [people, leads] = await Promise.all([
      personIds.length
        ? this.prisma.person.findMany({
            where: { id: { in: personIds } },
            select: {
              id: true,
              firstName: true,
              lastName: true,
              mobile: true,
              company: { select: { name: true } },
            },
          })
        : Promise.resolve([]),
      leadIds.length
        ? this.prisma.lead.findMany({
            where: { id: { in: leadIds } },
            select: {
              id: true,
              title: true,
              contactName: true,
              mobile: true,
            },
          })
        : Promise.resolve([]),
    ]);
    const personMap = new Map(people.map((p) => [p.id, p]));
    const leadMap = new Map(leads.map((l) => [l.id, l]));

    let sent = 0;
    let failed = 0;
    let skipped = 0;

    for (const recipient of batch) {
      if (!recipient.mobile) {
        await this.prisma.smsCampaignRecipient.update({
          where: { id: recipient.id },
          data: { status: 'skipped', error: 'موبایل ندارد' },
        });
        skipped += 1;
        continue;
      }

      let name = '';
      let title = '';
      let company = '';
      if (recipient.personId) {
        const p = personMap.get(recipient.personId);
        name = [p?.firstName, p?.lastName].filter(Boolean).join(' ').trim();
        title = name;
        company = p?.company?.name ?? '';
      } else if (recipient.leadId) {
        const l = leadMap.get(recipient.leadId);
        name = (l?.contactName || l?.title || '').trim();
        title = (l?.title || name).trim();
      }

      const withTokens = renderSmsText(campaign.body, {
        name,
        phone: recipient.mobile,
        title,
        company,
      });

      const personalized = await this.tracking.personalizeSmsBody({
        organizationId: campaign.organizationId,
        channel: 'sms',
        sourceType: 'sms_campaign',
        sourceId: campaign.id,
        recipientType: 'sms_campaign_recipient',
        recipientId: recipient.id,
        smsRecipientId: recipient.id,
        personId: recipient.personId,
        leadId: recipient.leadId,
        body: withTokens,
      });

      const result = await this.sms.sendSmsDetailed(
        recipient.mobile,
        personalized.body,
      );
      await this.outboundSms.record({
        organizationId: campaign.organizationId,
        personId: recipient.personId,
        leadId: recipient.leadId,
        mobile: recipient.mobile,
        body: personalized.body,
        source: 'campaign',
        sourceId: campaign.id,
        status: result.ok ? 'sent' : 'failed',
        error: result.ok ? null : result.reason,
      });
      if (result.ok) {
        await this.prisma.smsCampaignRecipient.update({
          where: { id: recipient.id },
          data: { status: 'sent', sentAt: new Date(), error: null },
        });
        sent += 1;
      } else {
        await this.prisma.smsCampaignRecipient.update({
          where: { id: recipient.id },
          data: {
            status: 'failed',
            error: result.reason?.slice(0, 200) ?? 'ارسال ناموفق',
          },
        });
        failed += 1;
      }
    }

    const remaining = await this.prisma.smsCampaignRecipient.count({
      where: { campaignId, status: 'pending' },
    });

    await this.prisma.smsCampaign.update({
      where: { id: campaignId },
      data: {
        sentCount: { increment: sent },
        failedCount: { increment: failed },
        skippedCount: { increment: skipped },
        status: remaining > 0 ? 'queued' : 'done',
        scheduledAt: remaining > 0 ? new Date() : campaign.scheduledAt,
      },
    });
  }

  private toDto(row: {
    id: string;
    name: string;
    body: string;
    status: string;
    scheduledAt: Date | null;
    totalCount: number;
    sentCount: number;
    failedCount: number;
    skippedCount: number;
    createdAt: Date;
    updatedAt: Date;
  }): SmsCampaignDto {
    return {
      id: row.id,
      name: row.name,
      body: row.body,
      status: row.status as SmsCampaignStatus,
      scheduledAt: row.scheduledAt?.toISOString() ?? null,
      totalCount: row.totalCount,
      sentCount: row.sentCount,
      failedCount: row.failedCount,
      skippedCount: row.skippedCount,
      createdAt: row.createdAt.toISOString(),
      updatedAt: row.updatedAt.toISOString(),
    };
  }
}