import { Injectable } from '@nestjs/common';
import { DataSource } from 'typeorm';

export interface DashboardInspectorActivityItem {
  id: string;
  occurredAt: Date;
  actorUsername: string | null;
  action: string;
  entityType: string | null;
  entityId: string | null;
}

interface DashboardCountsRow {
  totalAssets: number | string;
  assetsNeedValidation: number | string;
  assetsWithoutGeometry: number | string;
  plannedInspections: number | string;
  activeUsers: number | string;
  inactiveUsers: number | string;
  activeSessions: number | string;
  openFindings: number | string;
  actsInFollowUp: number | string;
  findingsWithoutControlDate: number | string;
  overdueControls: number | string;
  controlsNext30Days: number | string;
  reportsWorking: number | string;
  reportsOfficialized: number | string;
  sealedActsWithoutReport: number | string;
}

export interface DashboardUpcomingControl {
  id: string;
  code: string;
  title: string;
  nextControlOn: string;
  actId: string;
  actCode: string;
  visitId: string;
  visitCode: string;
  assetId: string;
  assetCode: string;
  assetName: string;
}

@Injectable()
export class DashboardService {
  constructor(private readonly dataSource: DataSource) {}

  async summary() {
    return this.dataSource.transaction('REPEATABLE READ', async (manager) => {
      const [counts] = (await manager.query(`
        SELECT
          (SELECT COUNT(*) FROM assets WHERE is_inventory_instance=true AND information_status <> 'INACTIVE') AS "totalAssets",
          (SELECT COUNT(*) FROM assets WHERE is_inventory_instance=true AND information_status NOT IN ('VALIDATED','INACTIVE')) AS "assetsNeedValidation",
          (
            SELECT COUNT(*) FROM assets asset
            WHERE asset.is_inventory_instance=true
              AND asset.information_status <> 'INACTIVE'
              AND NOT EXISTS (SELECT 1 FROM asset_geometries geometry WHERE geometry.asset_id=asset.id)
          ) AS "assetsWithoutGeometry",
          (SELECT COUNT(*) FROM inspection_visits WHERE status='PLANNED') AS "plannedInspections",
          (SELECT COUNT(*) FROM users WHERE status = 'ACTIVE') AS "activeUsers",
          (SELECT COUNT(*) FROM users WHERE status = 'INACTIVE') AS "inactiveUsers",
          (
            SELECT COUNT(*)
            FROM auth_sessions
            WHERE revoked_at IS NULL
              AND expires_at > CURRENT_TIMESTAMP
          ) AS "activeSessions",
          (SELECT COUNT(*) FROM inspection_findings WHERE status = 'OPEN') AS "openFindings",
          (
            SELECT COUNT(*)
            FROM inspection_acts act
            WHERE act.status IN ('SEALED','CLOSED','RECTIFIED')
              AND NOT (
                EXISTS (
                  SELECT 1 FROM inspection_findings finding
                  WHERE finding.act_id=act.id AND finding.status<>'VOIDED'
                )
                AND NOT EXISTS (
                  SELECT 1 FROM inspection_findings finding
                  WHERE finding.act_id=act.id AND finding.status='OPEN'
                )
              )
          ) AS "actsInFollowUp",
          (
            SELECT COUNT(*)
            FROM inspection_findings finding
            WHERE finding.status = 'OPEN'
              AND finding.next_control_on IS NULL
              AND COALESCE((
                SELECT verification.outcome
                FROM inspection_finding_verification_visits verification
                WHERE verification.finding_id=finding.id AND verification.outcome IS NOT NULL
                ORDER BY verification.result_recorded_at DESC NULLS LAST, verification.created_at DESC, verification.id DESC
                LIMIT 1
              ), '') <> 'RESOLVED'
          ) AS "findingsWithoutControlDate",
          (
            SELECT COUNT(*)
            FROM inspection_findings finding
            WHERE finding.status = 'OPEN'
              AND finding.next_control_on < (CURRENT_TIMESTAMP AT TIME ZONE 'America/Argentina/Mendoza')::date
              AND COALESCE((
                SELECT verification.outcome
                FROM inspection_finding_verification_visits verification
                WHERE verification.finding_id=finding.id AND verification.outcome IS NOT NULL
                ORDER BY verification.result_recorded_at DESC NULLS LAST, verification.created_at DESC, verification.id DESC
                LIMIT 1
              ), '') <> 'RESOLVED'
          ) AS "overdueControls",
          (
            SELECT COUNT(*)
            FROM inspection_findings finding
            WHERE finding.status = 'OPEN'
              AND finding.next_control_on BETWEEN
                (CURRENT_TIMESTAMP AT TIME ZONE 'America/Argentina/Mendoza')::date
                AND (CURRENT_TIMESTAMP AT TIME ZONE 'America/Argentina/Mendoza')::date + 30
              AND COALESCE((
                SELECT verification.outcome
                FROM inspection_finding_verification_visits verification
                WHERE verification.finding_id=finding.id AND verification.outcome IS NOT NULL
                ORDER BY verification.result_recorded_at DESC NULLS LAST, verification.created_at DESC, verification.id DESC
                LIMIT 1
              ), '') <> 'RESOLVED'
          ) AS "controlsNext30Days",
          (SELECT COUNT(*) FROM inspection_reports WHERE status='WORKING') AS "reportsWorking",
          (SELECT COUNT(*) FROM inspection_reports WHERE status='OFFICIALIZED') AS "reportsOfficialized",
          (
            SELECT COUNT(*)
            FROM inspection_acts act
            WHERE act.status='SEALED'
              AND NOT EXISTS (SELECT 1 FROM inspection_reports report WHERE report.act_id=act.id)
          ) AS "sealedActsWithoutReport"
      `)) as DashboardCountsRow[];

      const recentInspectorActivity = (await manager.query(`
        SELECT
          event.id,
          event.occurred_at AS "occurredAt",
          event.actor_username AS "actorUsername",
          event.action,
          event.entity_type AS "entityType",
          event.entity_id AS "entityId"
        FROM audit_events event
        WHERE event.actor_user_id IS NOT NULL
          AND (
            EXISTS (
              SELECT 1 FROM inspection_visit_members member
              WHERE member.user_id=event.actor_user_id AND member.included=true
            )
            OR EXISTS (
              SELECT 1 FROM inspection_visits visit
              WHERE visit.lead_inspector_user_id=event.actor_user_id
            )
          )
          AND (
            event.action LIKE 'INSPECTION_%'
            OR event.action LIKE 'ASSET_%'
            OR event.action LIKE 'FINDING_%'
          )
        ORDER BY event.occurred_at DESC, event.id DESC
        LIMIT 8
      `)) as DashboardInspectorActivityItem[];

      const upcomingControls = (await manager.query(`
        SELECT
          finding.id,
          finding.code,
          finding.title,
          finding.next_control_on AS "nextControlOn",
          act.id AS "actId",
          act.code AS "actCode",
          visit.id AS "visitId",
          visit.code AS "visitCode",
          asset.id AS "assetId",
          asset.code AS "assetCode",
          asset.name AS "assetName"
        FROM inspection_findings finding
        INNER JOIN inspection_acts act ON act.id = finding.act_id
        INNER JOIN inspection_visits visit ON visit.id = act.visit_id
        INNER JOIN assets asset ON asset.id = finding.asset_id
        WHERE finding.status = 'OPEN'
          AND finding.next_control_on IS NOT NULL
          AND COALESCE((
            SELECT verification.outcome
            FROM inspection_finding_verification_visits verification
            WHERE verification.finding_id=finding.id AND verification.outcome IS NOT NULL
            ORDER BY verification.result_recorded_at DESC NULLS LAST, verification.created_at DESC, verification.id DESC
            LIMIT 1
          ), '') <> 'RESOLVED'
        ORDER BY finding.next_control_on, finding.code
        LIMIT 8
      `)) as DashboardUpcomingControl[];

      return {
        counts: {
          totalAssets: Number(counts?.totalAssets ?? 0),
          assetsNeedValidation: Number(counts?.assetsNeedValidation ?? 0),
          assetsWithoutGeometry: Number(counts?.assetsWithoutGeometry ?? 0),
          plannedInspections: Number(counts?.plannedInspections ?? 0),
          activeUsers: Number(counts?.activeUsers ?? 0),
          inactiveUsers: Number(counts?.inactiveUsers ?? 0),
          activeSessions: Number(counts?.activeSessions ?? 0),
          openFindings: Number(counts?.openFindings ?? 0),
          actsInFollowUp: Number(counts?.actsInFollowUp ?? 0),
          findingsWithoutControlDate: Number(counts?.findingsWithoutControlDate ?? 0),
          overdueControls: Number(counts?.overdueControls ?? 0),
          controlsNext30Days: Number(counts?.controlsNext30Days ?? 0),
          reportsWorking: Number(counts?.reportsWorking ?? 0),
          reportsOfficialized: Number(counts?.reportsOfficialized ?? 0),
          sealedActsWithoutReport: Number(counts?.sealedActsWithoutReport ?? 0),
        },
        recentInspectorActivity,
        upcomingControls,
        generatedAt: new Date().toISOString(),
      };
    });
  }
}