import { MigrationInterface, QueryRunner } from 'typeorm';

function quoteIdentifier(identifier: string): string {
  return `"${identifier.replaceAll('"', '""')}"`;
}

export class PhaseD55WebPlanningChecklist1789063200000 implements MigrationInterface {
  name = 'PhaseD55WebPlanningChecklist1789063200000';

  public async up(queryRunner: QueryRunner): Promise<void> {
    await queryRunner.query(`
      ALTER TABLE inspection_visits
        ADD COLUMN operational_area_id uuid,
        ADD COLUMN operator_company_id uuid,
        ADD COLUMN checklist_generation integer NOT NULL DEFAULT 0,
        ADD COLUMN checklist_generated_at timestamptz,
        ADD CONSTRAINT fk_inspection_visits_operational_area FOREIGN KEY (operational_area_id)
          REFERENCES assets(id) ON DELETE RESTRICT,
        ADD CONSTRAINT fk_inspection_visits_operator_company FOREIGN KEY (operator_company_id)
          REFERENCES assets(id) ON DELETE RESTRICT,
        ADD CONSTRAINT chk_inspection_visits_checklist_generation CHECK (checklist_generation >= 0),
        ADD CONSTRAINT chk_inspection_visits_operational_context_pair CHECK (
          (operational_area_id IS NULL AND operator_company_id IS NULL)
          OR (operational_area_id IS NOT NULL AND operator_company_id IS NOT NULL)
        )
    `);
    await queryRunner.query(`CREATE INDEX idx_inspection_visits_operational_context ON inspection_visits (operational_area_id, operator_company_id)`);

    await queryRunner.query(`
      WITH context AS (
        SELECT
          visit.id,
          COALESCE(
            (MAX(scope.id::text) FILTER (WHERE scope_type.operational_role = 'AREA'))::uuid,
            MIN(asset.operational_area_id::text)::uuid
          ) AS area_id,
          CASE
            WHEN COUNT(DISTINCT asset.operator_company_id) FILTER (WHERE asset.operator_company_id IS NOT NULL) = 1
              THEN MIN(asset.operator_company_id::text)::uuid
            ELSE NULL
          END AS company_id
        FROM inspection_visits visit
        LEFT JOIN assets scope ON scope.id = visit.scope_asset_id
        LEFT JOIN asset_types scope_type ON scope_type.id = scope.asset_type_id
        LEFT JOIN inspection_visit_assets link ON link.visit_id = visit.id AND link.included = true
        LEFT JOIN assets asset ON asset.id = link.asset_id
        GROUP BY visit.id
      )
      UPDATE inspection_visits visit
      SET operational_area_id = context.area_id,
          operator_company_id = context.company_id
      FROM context
      WHERE context.id = visit.id
        AND context.area_id IS NOT NULL
        AND context.company_id IS NOT NULL
    `);

    await queryRunner.query(`
      ALTER TABLE inspection_visit_assets
        ADD COLUMN planning_source varchar(24) NOT NULL DEFAULT 'LEGACY',
        ADD COLUMN exclusion_reason text,
        ADD COLUMN excluded_by uuid,
        ADD COLUMN excluded_at timestamptz,
        ADD CONSTRAINT fk_inspection_visit_assets_excluded_by FOREIGN KEY (excluded_by)
          REFERENCES users(id) ON DELETE SET NULL,
        ADD CONSTRAINT chk_inspection_visit_assets_planning_source CHECK (
          planning_source IN ('LEGACY','AUTOMATIC','PREVENTIVE','VERIFICATION')
        )
    `);
    await queryRunner.query(`
      UPDATE inspection_visit_assets link
      SET planning_source = 'VERIFICATION'
      WHERE EXISTS (
        SELECT 1
        FROM inspection_finding_verification_visits verification_link
        INNER JOIN inspection_findings finding ON finding.id = verification_link.finding_id
        WHERE verification_link.visit_id = link.visit_id
          AND finding.asset_id = link.asset_id
      )
    `);
    await queryRunner.query(`
      UPDATE inspection_visit_assets
      SET exclusion_reason = 'Exclusión histórica previa a D5.5',
          excluded_by = added_by,
          excluded_at = updated_at
      WHERE included = false
        AND exclusion_reason IS NULL
    `);
    await queryRunner.query(`
      ALTER TABLE inspection_visit_assets
        ADD CONSTRAINT chk_inspection_visit_assets_exclusion_state CHECK (
          (included = true AND exclusion_reason IS NULL AND excluded_at IS NULL)
          OR (included = false AND LENGTH(TRIM(COALESCE(exclusion_reason, ''))) >= 10 AND excluded_at IS NOT NULL)
        )
    `);

    await queryRunner.query(`
      CREATE TABLE inspection_visit_checklist_items (
        id uuid PRIMARY KEY DEFAULT gen_random_uuid(),
        visit_id uuid NOT NULL,
        generation_number integer NOT NULL,
        finding_id uuid NOT NULL,
        asset_id uuid NOT NULL,
        item_kind varchar(32) NOT NULL,
        reference_on date,
        finding_status varchar(20) NOT NULL,
        finding_code varchar(40) NOT NULL,
        finding_title varchar(500) NOT NULL,
        severity smallint,
        created_at timestamptz NOT NULL DEFAULT CURRENT_TIMESTAMP,
        CONSTRAINT fk_inspection_visit_checklist_visit FOREIGN KEY (visit_id)
          REFERENCES inspection_visits(id) ON DELETE RESTRICT,
        CONSTRAINT fk_inspection_visit_checklist_finding FOREIGN KEY (finding_id)
          REFERENCES inspection_findings(id) ON DELETE RESTRICT,
        CONSTRAINT fk_inspection_visit_checklist_asset FOREIGN KEY (asset_id)
          REFERENCES assets(id) ON DELETE RESTRICT,
        CONSTRAINT uq_inspection_visit_checklist_generation_finding UNIQUE (visit_id, generation_number, finding_id),
        CONSTRAINT chk_inspection_visit_checklist_generation CHECK (generation_number > 0),
        CONSTRAINT chk_inspection_visit_checklist_kind CHECK (
          item_kind IN ('ANTECEDENT','COMPANY_OVERDUE','VERIFICATION_OVERDUE','UPCOMING_CONTROL')
        ),
        CONSTRAINT chk_inspection_visit_checklist_severity CHECK (severity IS NULL OR severity BETWEEN 1 AND 10)
      )
    `);
    await queryRunner.query(`CREATE INDEX idx_inspection_visit_checklist_current ON inspection_visit_checklist_items (visit_id, generation_number, item_kind)`);
    await queryRunner.query(`CREATE INDEX idx_inspection_visit_checklist_asset ON inspection_visit_checklist_items (visit_id, generation_number, asset_id)`);

    await queryRunner.query(`
      CREATE TABLE inspection_visit_asset_events (
        id uuid PRIMARY KEY DEFAULT gen_random_uuid(),
        visit_id uuid NOT NULL,
        asset_id uuid NOT NULL,
        event_type varchar(32) NOT NULL,
        reason text,
        actor_user_id uuid,
        occurred_at timestamptz NOT NULL DEFAULT CURRENT_TIMESTAMP,
        metadata jsonb,
        CONSTRAINT fk_inspection_visit_asset_events_visit FOREIGN KEY (visit_id)
          REFERENCES inspection_visits(id) ON DELETE RESTRICT,
        CONSTRAINT fk_inspection_visit_asset_events_asset FOREIGN KEY (asset_id)
          REFERENCES assets(id) ON DELETE RESTRICT,
        CONSTRAINT fk_inspection_visit_asset_events_actor FOREIGN KEY (actor_user_id)
          REFERENCES users(id) ON DELETE SET NULL,
        CONSTRAINT chk_inspection_visit_asset_events_type CHECK (
          event_type IN ('LEGACY_INCLUDED','AUTO_INCLUDED','PREVENTIVE_INCLUDED','VERIFICATION_INCLUDED','EXCLUDED','REINCLUDED')
        ),
        CONSTRAINT chk_inspection_visit_asset_events_exclusion_reason CHECK (
          event_type <> 'EXCLUDED' OR LENGTH(TRIM(COALESCE(reason, ''))) >= 10
        )
      )
    `);
    await queryRunner.query(`CREATE INDEX idx_inspection_visit_asset_events_visit ON inspection_visit_asset_events (visit_id, occurred_at, id)`);
    await queryRunner.query(`CREATE INDEX idx_inspection_visit_asset_events_asset ON inspection_visit_asset_events (asset_id, occurred_at, id)`);

    await queryRunner.query(`
      INSERT INTO inspection_visit_asset_events (
        visit_id, asset_id, event_type, actor_user_id, occurred_at, metadata
      )
      SELECT
        link.visit_id,
        link.asset_id,
        CASE WHEN link.planning_source = 'VERIFICATION' THEN 'VERIFICATION_INCLUDED' ELSE 'LEGACY_INCLUDED' END,
        link.added_by,
        link.created_at,
        JSONB_BUILD_OBJECT('backfill', true, 'planningSource', link.planning_source)
      FROM inspection_visit_assets link
    `);
    await queryRunner.query(`
      INSERT INTO inspection_visit_asset_events (
        visit_id, asset_id, event_type, reason, actor_user_id, occurred_at, metadata
      )
      SELECT
        link.visit_id,
        link.asset_id,
        'EXCLUDED',
        link.exclusion_reason,
        link.excluded_by,
        COALESCE(link.excluded_at, link.updated_at),
        JSONB_BUILD_OBJECT('backfill', true)
      FROM inspection_visit_assets link
      WHERE link.included = false
    `);

    const appRole = process.env.DB_APP_USER;
    if (!appRole) throw new Error('Missing required environment variable: DB_APP_USER');
    const applicationRole = quoteIdentifier(appRole);
    await queryRunner.query(`
      GRANT SELECT, INSERT ON TABLE
        inspection_visit_checklist_items, inspection_visit_asset_events
      TO ${applicationRole}
    `);
    await queryRunner.query(`
      REVOKE UPDATE, DELETE ON TABLE
        inspection_visit_checklist_items, inspection_visit_asset_events
      FROM ${applicationRole}
    `);
  }

  public async down(queryRunner: QueryRunner): Promise<void> {
    await queryRunner.query(`DROP TABLE inspection_visit_asset_events`);
    await queryRunner.query(`DROP TABLE inspection_visit_checklist_items`);
    await queryRunner.query(`ALTER TABLE inspection_visit_assets DROP CONSTRAINT chk_inspection_visit_assets_exclusion_state`);
    await queryRunner.query(`ALTER TABLE inspection_visit_assets DROP CONSTRAINT fk_inspection_visit_assets_excluded_by`);
    await queryRunner.query(`ALTER TABLE inspection_visit_assets DROP CONSTRAINT chk_inspection_visit_assets_planning_source`);
    await queryRunner.query(`ALTER TABLE inspection_visit_assets DROP COLUMN excluded_at`);
    await queryRunner.query(`ALTER TABLE inspection_visit_assets DROP COLUMN excluded_by`);
    await queryRunner.query(`ALTER TABLE inspection_visit_assets DROP COLUMN exclusion_reason`);
    await queryRunner.query(`ALTER TABLE inspection_visit_assets DROP COLUMN planning_source`);
    await queryRunner.query(`DROP INDEX idx_inspection_visits_operational_context`);
    await queryRunner.query(`ALTER TABLE inspection_visits DROP CONSTRAINT chk_inspection_visits_operational_context_pair`);
    await queryRunner.query(`ALTER TABLE inspection_visits DROP CONSTRAINT chk_inspection_visits_checklist_generation`);
    await queryRunner.query(`ALTER TABLE inspection_visits DROP CONSTRAINT fk_inspection_visits_operator_company`);
    await queryRunner.query(`ALTER TABLE inspection_visits DROP CONSTRAINT fk_inspection_visits_operational_area`);
    await queryRunner.query(`ALTER TABLE inspection_visits DROP COLUMN checklist_generated_at`);
    await queryRunner.query(`ALTER TABLE inspection_visits DROP COLUMN checklist_generation`);
    await queryRunner.query(`ALTER TABLE inspection_visits DROP COLUMN operator_company_id`);
    await queryRunner.query(`ALTER TABLE inspection_visits DROP COLUMN operational_area_id`);
  }
}