import {
  BadRequestException,
  ConflictException,
  ForbiddenException,
  Injectable,
  NotFoundException,
} from '@nestjs/common';
import { DataSource, EntityManager } from 'typeorm';
import { administrationAuditContext } from '../administration/common/administration-audit';
import { AuditService } from '../audit/audit.service';
import type { AuthPrincipal, RequestWithContext } from '../common/http/request-context';
import { AuditAction, InspectionVisit, InspectionVisitStatus } from '../database/entities';
import { assertMobileInspector } from '../inspection-operations/mobile-inspector-policy';
import type { CancelInspectionVisitDto } from './dto/cancel-inspection-visit.dto';
import type { CloseInspectionVisitDto } from './dto/close-inspection-visit.dto';
import { InspectionVisitsService } from './inspection-visits.service';

interface PendingActRow {
  id: string;
  code: string;
  status: string;
}

@Injectable()
export class InspectionVisitLifecycleService {
  constructor(
    private readonly dataSource: DataSource,
    private readonly audit: AuditService,
    private readonly visits: InspectionVisitsService,
  ) {}

  async plan(
    id: string,
    principal: AuthPrincipal,
    request: RequestWithContext,
  ) {
    await this.dataSource.transaction(async (manager) => {
      const visit = await this.lockVisit(manager, id);
      if (visit.status !== InspectionVisitStatus.DRAFT) {
        throw new ConflictException({
          code: 'INSPECTION_NOT_DRAFT',
          message: 'Sólo una Inspección en borrador puede planificarse',
        });
      }
      await this.validatePlanningContext(manager, visit);
      const before = visit.status;
      visit.status = InspectionVisitStatus.PLANNED;
      visit.cancellationReason = null;
      visit.updatedBy = principal.userId;
      await manager.getRepository(InspectionVisit).save(visit);
      await this.audit.record({
        ...administrationAuditContext(principal, request),
        action: AuditAction.INSPECTION_VISIT_STATUS_CHANGED,
        entityType: 'inspection_visit',
        entityId: id,
        beforeData: { status: before },
        afterData: { status: InspectionVisitStatus.PLANNED },
        metadata: { transition: 'PLAN' },
      }, manager);
    });
    return this.visits.getById(id);
  }

  async start(
    id: string,
    principal: AuthPrincipal,
    request: RequestWithContext,
  ) {
    assertMobileInspector(principal);
    await this.dataSource.transaction(async (manager) => {
      const visit = await this.lockVisit(manager, id);
      if (visit.status !== InspectionVisitStatus.PLANNED) {
        throw new ConflictException({
          code: 'INSPECTION_NOT_PLANNED',
          message: 'La Inspección debe estar planificada antes de iniciarse',
        });
      }
      await this.validatePlanningContext(manager, visit);
      await this.assertActorAssigned(manager, visit, principal);
      const startedAt = new Date();
      visit.status = InspectionVisitStatus.IN_PROGRESS;
      visit.actualStartedAt = startedAt;
      visit.updatedBy = principal.userId;
      await manager.getRepository(InspectionVisit).save(visit);
      await this.audit.record({
        ...administrationAuditContext(principal, request),
        action: AuditAction.INSPECTION_VISIT_STARTED,
        entityType: 'inspection_visit',
        entityId: id,
        beforeData: { status: InspectionVisitStatus.PLANNED, actualStartedAt: null },
        afterData: { status: InspectionVisitStatus.IN_PROGRESS, actualStartedAt: startedAt },
        metadata: { transition: 'START', source: 'ANDROID' },
      }, manager);
    });
    return this.visits.getById(id);
  }

  async close(
    id: string,
    dto: CloseInspectionVisitDto,
    principal: AuthPrincipal,
    request: RequestWithContext,
  ) {
    assertMobileInspector(principal);
    await this.dataSource.transaction(async (manager) => {
      const visit = await this.lockVisit(manager, id);
      if (visit.status !== InspectionVisitStatus.IN_PROGRESS) {
        throw new ConflictException({
          code: 'INSPECTION_NOT_IN_PROGRESS',
          message: 'La Inspección debe estar en curso para cerrarse',
        });
      }
      await this.assertActorAssigned(manager, visit, principal);

      const acts = await manager.query(`
        SELECT id,code,status
        FROM inspection_acts
        WHERE visit_id=$1 AND status<>'CANCELLED'
        ORDER BY occurred_at,created_at,id
        FOR UPDATE
      `, [id]) as PendingActRow[];
      if (acts.length === 0) {
        throw new ConflictException({
          code: 'INSPECTION_REQUIRES_ACT',
          message: 'La Inspección debe tener al menos un Acta antes de cerrarse',
        });
      }
      const pending = acts.filter((act) => act.status !== 'SEALED');
      if (pending.length > 0) {
        throw new ConflictException({
          code: 'INSPECTION_ACTS_NOT_SEALED',
          message: 'Todas las Actas deben estar SELLADAS antes de cerrar la Inspección',
          pendingActs: pending.map((act) => ({ id: act.id, code: act.code, status: act.status })),
        });
      }

      const serverClosedAt = new Date();
      const clientClosedAt = new Date(dto.clientClosedAt);
      if (!Number.isFinite(clientClosedAt.getTime())) {
        throw new BadRequestException({
          code: 'INSPECTION_CLOSE_TIME_INVALID',
          message: 'La fecha de cierre informada por el dispositivo no es válida',
        });
      }
      if (visit.actualStartedAt && clientClosedAt.getTime() < visit.actualStartedAt.getTime()) {
        throw new BadRequestException({
          code: 'INSPECTION_CLOSE_BEFORE_START',
          message: 'La fecha de cierre no puede ser anterior al inicio de la Inspección',
        });
      }
      if (clientClosedAt.getTime() > serverClosedAt.getTime() + 24 * 60 * 60 * 1000) {
        throw new BadRequestException({
          code: 'INSPECTION_CLOSE_TIME_IN_FUTURE',
          message: 'La fecha del dispositivo no puede estar más de 24 horas en el futuro',
        });
      }

      visit.status = InspectionVisitStatus.CLOSED;
      visit.actualClosedAt = serverClosedAt;
      visit.updatedBy = principal.userId;
      await manager.getRepository(InspectionVisit).save(visit);
      await this.audit.record({
        ...administrationAuditContext(principal, request),
        action: AuditAction.INSPECTION_VISIT_STATUS_CHANGED,
        entityType: 'inspection_visit',
        entityId: id,
        beforeData: { status: InspectionVisitStatus.IN_PROGRESS },
        afterData: {
          status: InspectionVisitStatus.CLOSED,
          clientClosedAt: clientClosedAt.toISOString(),
          serverClosedAt: serverClosedAt.toISOString(),
          sealedActs: acts.length,
        },
        metadata: {
          transition: 'CLOSE',
          source: 'ANDROID',
          allActsSealed: true,
        },
      }, manager);
    });
    return this.visits.getById(id);
  }

  async cancel(
    id: string,
    dto: CancelInspectionVisitDto,
    principal: AuthPrincipal,
    request: RequestWithContext,
  ) {
    await this.dataSource.transaction(async (manager) => {
      const visit = await this.lockVisit(manager, id);
      if (![InspectionVisitStatus.DRAFT, InspectionVisitStatus.PLANNED, InspectionVisitStatus.IN_PROGRESS].includes(visit.status)) {
        throw new ConflictException({
          code: 'INSPECTION_CANNOT_CANCEL',
          message: 'La Inspección ya no puede cancelarse en su estado actual',
        });
      }
      const [sealedAct] = await manager.query(`
        SELECT 1 FROM inspection_acts
        WHERE visit_id=$1 AND status='SEALED'
        LIMIT 1
      `, [id]) as unknown[];
      if (sealedAct) {
        throw new ConflictException({
          code: 'INSPECTION_WITH_SEALED_ACT_CANNOT_CANCEL',
          message: 'Una Inspección con Actas SELLADAS no puede cancelarse',
        });
      }
      const before = visit.status;
      visit.status = InspectionVisitStatus.CANCELLED;
      visit.cancellationReason = dto.reason;
      visit.updatedBy = principal.userId;
      await manager.getRepository(InspectionVisit).save(visit);
      await this.audit.record({
        ...administrationAuditContext(principal, request),
        action: AuditAction.INSPECTION_VISIT_STATUS_CHANGED,
        entityType: 'inspection_visit',
        entityId: id,
        beforeData: { status: before },
        afterData: { status: InspectionVisitStatus.CANCELLED, cancellationReason: dto.reason },
        metadata: { transition: 'CANCEL' },
      }, manager);
    });
    return this.visits.getById(id);
  }

  private async lockVisit(manager: EntityManager, id: string): Promise<InspectionVisit> {
    const visit = await manager.getRepository(InspectionVisit)
      .createQueryBuilder('visit')
      .where('visit.id=:id', { id })
      .setLock('pessimistic_write')
      .getOne();
    if (!visit) {
      throw new NotFoundException({ code: 'INSPECTION_NOT_FOUND', message: 'Inspección no encontrada' });
    }
    return visit;
  }

  private async validatePlanningContext(manager: EntityManager, visit: InspectionVisit): Promise<void> {
    if (!visit.operationalAreaId || !visit.operatorCompanyId || !visit.leadInspectorUserId || !visit.plannedStartAt) {
      throw new ConflictException({
        code: 'INSPECTION_PLANNING_INCOMPLETE',
        message: 'Definí Área/Yacimiento, Operadora, Inspector responsable y fecha de inicio antes de planificar',
      });
    }
    const [relation] = await manager.query(`
      SELECT 1
      FROM area_company_relations
      WHERE area_id=$1 AND company_id=$2
        AND relation_role='OPERATOR'
        AND valid_from<=CURRENT_TIMESTAMP
        AND (valid_until IS NULL OR valid_until>CURRENT_TIMESTAMP)
      LIMIT 1
    `, [visit.operationalAreaId, visit.operatorCompanyId]) as unknown[];
    if (!relation) {
      throw new ConflictException({
        code: 'INSPECTION_OPERATOR_RELATION_INVALID',
        message: 'La Operadora seleccionada no tiene una relación operativa vigente con el Área/Yacimiento',
      });
    }
    const [inspector] = await manager.query(`
      SELECT 1
      FROM users user_account
      JOIN user_roles user_role ON user_role.user_id=user_account.id
      JOIN role_permissions role_permission ON role_permission.role_id=user_role.role_id
      JOIN permissions permission ON permission.id=role_permission.permission_id
      WHERE user_account.id=$1 AND user_account.status='ACTIVE'
        AND permission.code='inspections.execute'
      LIMIT 1
    `, [visit.leadInspectorUserId]) as unknown[];
    if (!inspector) {
      throw new ConflictException({
        code: 'INSPECTION_LEAD_INVALID',
        message: 'El Inspector responsable no está activo o no puede ejecutar Inspecciones',
      });
    }
  }

  private async assertActorAssigned(
    manager: EntityManager,
    visit: InspectionVisit,
    principal: AuthPrincipal,
  ): Promise<void> {
    if (principal.permissions.includes('inspections.manage')) return;
    const [member] = await manager.query(`
      SELECT 1 FROM inspection_visit_members
      WHERE visit_id=$1 AND user_id=$2 AND included=true
      LIMIT 1
    `, [visit.id, principal.userId]) as unknown[];
    if (!member && visit.leadInspectorUserId !== principal.userId) {
      throw new ForbiddenException({
        code: 'INSPECTION_NOT_ASSIGNED',
        message: 'La Inspección no está asignada al usuario actual',
      });
    }
  }
}