import { and, desc, eq, exists, inArray, isNull, sql } from 'drizzle-orm';

import { db } from '@/lib/db';
import { interests, interestBerths, interestTags, interestNotes } from '@/lib/db/schema/interests';
import { reminders } from '@/lib/db/schema/operations';
import { clients, clientAddresses, clientContacts } from '@/lib/db/schema/clients';
import { berths } from '@/lib/db/schema/berths';
import { yachts } from '@/lib/db/schema/yachts';
import { companyMemberships } from '@/lib/db/schema/companies';
import { tags } from '@/lib/db/schema/system';
import { createAuditLog, type AuditMeta } from '@/lib/audit';
import { getPortReminderConfig } from '@/lib/services/port-config';
import { NotFoundError, ConflictError, ValidationError } from '@/lib/errors';
import { emitToRoom } from '@/lib/socket/server';
import { setEntityTags } from '@/lib/services/entity-tags.helper';
import {
  getPrimaryBerth,
  getPrimaryBerthsForInterests,
  removeInterestBerth,
  upsertInterestBerth,
  upsertInterestBerthTx,
} from '@/lib/services/interest-berths.service';
import { buildListQuery } from '@/lib/db/query-builder';
import { diffEntity } from '@/lib/entity-diff';
import { softDelete, restore, withTransaction } from '@/lib/db/utils';
import { PIPELINE_STAGES, canTransitionStage, type PipelineStage } from '@/lib/constants';
import type {
  CreateInterestInput,
  UpdateInterestInput,
  ChangeStageInput,
  ListInterestsInput,
  SetOutcomeInput,
  ClearOutcomeInput,
} from '@/lib/validators/interests';

// ─── Types ────────────────────────────────────────────────────────────────────

// ─── Port-scope FK validator ─────────────────────────────────────────────────

// Tenant scope: every FK referenced from an interest body - clientId, berthId,
// and yachtId - must belong to the caller's port. Without this, a body-supplied
// foreign-port id would create an interest that joins through these FKs and
// surfaces foreign-tenant data on subsequent reads (clientName, berth mooring
// number, yacht ownership). assertYachtBelongsToClient still runs separately to
// enforce the additional ownership invariant.
async function assertInterestFksInPort(
  portId: string,
  fks: { clientId?: string | null; berthId?: string | null; yachtId?: string | null },
): Promise<void> {
  const checks: Array<Promise<void>> = [];
  if (fks.clientId) {
    checks.push(
      db.query.clients
        .findFirst({ where: and(eq(clients.id, fks.clientId), eq(clients.portId, portId)) })
        .then((row) => {
          if (!row) throw new ValidationError('clientId not found in this port');
        }),
    );
  }
  if (fks.berthId) {
    checks.push(
      db.query.berths
        .findFirst({ where: and(eq(berths.id, fks.berthId), eq(berths.portId, portId)) })
        .then((row) => {
          if (!row) throw new ValidationError('berthId not found in this port');
        }),
    );
  }
  if (fks.yachtId) {
    checks.push(
      db.query.yachts
        .findFirst({ where: and(eq(yachts.id, fks.yachtId), eq(yachts.portId, portId)) })
        .then((row) => {
          if (!row) throw new ValidationError('yachtId not found in this port');
        }),
    );
  }
  await Promise.all(checks);
}

// ─── Yacht ownership validator ───────────────────────────────────────────────

async function assertYachtBelongsToClient(
  portId: string,
  yachtId: string,
  clientId: string,
): Promise<void> {
  const yacht = await db.query.yachts.findFirst({
    where: and(eq(yachts.id, yachtId), eq(yachts.portId, portId)),
  });
  if (!yacht) throw new ValidationError('yacht not found');

  // Direct ownership by client
  if (yacht.currentOwnerType === 'client' && yacht.currentOwnerId === clientId) {
    return;
  }

  // Company-represented: client has active membership in the owning company
  if (yacht.currentOwnerType === 'company') {
    const membership = await db.query.companyMemberships.findFirst({
      where: and(
        eq(companyMemberships.companyId, yacht.currentOwnerId),
        eq(companyMemberships.clientId, clientId),
        isNull(companyMemberships.endDate),
      ),
    });
    if (membership) return;
  }

  throw new ValidationError('yacht does not belong to this client');
}

// ─── BR-011: Auto-promote leadCategory ───────────────────────────────────────

async function resolveLeadCategory(
  clientId: string,
  leadCategory: string | undefined | null,
  yachtId?: string | null,
): Promise<string | undefined> {
  if (leadCategory && leadCategory !== 'general_interest') {
    return leadCategory;
  }

  if (yachtId) {
    const yacht = await db.query.yachts.findFirst({ where: eq(yachts.id, yachtId) });
    if (yacht && (yacht.lengthFt || yacht.lengthM)) {
      return 'specific_qualified';
    }
  }

  return leadCategory ?? undefined;
}

// ─── List ─────────────────────────────────────────────────────────────────────

export async function listInterests(portId: string, query: ListInterestsInput) {
  const {
    page,
    limit,
    sort,
    order,
    search,
    includeArchived,
    clientId,
    yachtId,
    berthId,
    pipelineStage,
    leadCategory,
    eoiStatus,
    tagIds,
  } = query;

  const filters = [];

  if (clientId) {
    filters.push(eq(interests.clientId, clientId));
  }
  if (yachtId) {
    filters.push(eq(interests.yachtId, yachtId));
  }
  if (berthId) {
    // EXISTS subquery against the junction: matches whether or not the
    // berth is the interest's primary, mirroring "this berth is linked
    // to this interest in any role" semantics from plan §3.4.
    filters.push(
      exists(
        db
          .select({ one: sql`1` })
          .from(interestBerths)
          .where(
            and(eq(interestBerths.interestId, interests.id), eq(interestBerths.berthId, berthId)),
          ),
      ),
    );
  }
  if (pipelineStage && pipelineStage.length > 0) {
    filters.push(inArray(interests.pipelineStage, pipelineStage));
  }
  if (leadCategory) {
    filters.push(eq(interests.leadCategory, leadCategory));
  }
  if (eoiStatus) {
    filters.push(eq(interests.eoiStatus, eoiStatus));
  }
  if (tagIds && tagIds.length > 0) {
    const interestsWithTags = await db
      .selectDistinct({ interestId: interestTags.interestId })
      .from(interestTags)
      .where(inArray(interestTags.tagId, tagIds));
    const matchingIds = interestsWithTags.map((r) => r.interestId);
    if (matchingIds.length > 0) {
      filters.push(inArray(interests.id, matchingIds));
    } else {
      return { data: [], total: 0 };
    }
  }

  const sortColumn = (() => {
    switch (sort) {
      case 'pipelineStage':
        return interests.pipelineStage;
      case 'leadCategory':
        return interests.leadCategory;
      case 'createdAt':
        return interests.createdAt;
      case 'dateLastContact':
        // Postgres sorts NULLs last on DESC by default, which is the right
        // behaviour for triage (recently-contacted first, never-contacted
        // at the bottom).
        return interests.dateLastContact;
      default:
        return interests.updatedAt;
    }
  })();

  const result = await buildListQuery({
    table: interests,
    portIdColumn: interests.portId,
    portId,
    idColumn: interests.id,
    updatedAtColumn: interests.updatedAt,
    filters,
    sort: { column: sortColumn, direction: order },
    page,
    pageSize: limit,
    searchColumns: [],
    searchTerm: search,
    includeArchived,
    archivedAtColumn: interests.archivedAt,
  });

  // Join client names, primary-berth mooring numbers, and yacht names.
  const interestIds = (result.data as Array<{ id: string; clientId: string }>).map((i) => i.id);
  const clientIds = [
    ...new Set((result.data as Array<{ clientId: string }>).map((i) => i.clientId)),
  ];
  const yachtIds = [
    ...new Set(
      (result.data as Array<{ yachtId: string | null }>)
        .map((i) => i.yachtId)
        .filter(Boolean) as string[],
    ),
  ];

  let clientsMap: Record<string, string> = {};
  let yachtsMap: Record<string, string> = {};
  const tagsByInterestId: Record<string, Array<{ id: string; name: string; color: string }>> = {};
  const notesCountByInterestId: Record<string, number> = {};

  if (clientIds.length > 0) {
    const clientRows = await db
      .select({ id: clients.id, fullName: clients.fullName })
      .from(clients)
      .where(inArray(clients.id, clientIds));
    clientsMap = Object.fromEntries(clientRows.map((c) => [c.id, c.fullName]));
  }

  // Primary-berth lookup via the interest_berths junction. Single round-trip
  // by interestId list - see plan §3.4: every "the berth for this interest"
  // surface resolves through getPrimaryBerth(...) rather than a column read.
  const primaryBerthMap = await getPrimaryBerthsForInterests(interestIds);

  if (yachtIds.length > 0) {
    const yachtRows = await db
      .select({ id: yachts.id, name: yachts.name })
      .from(yachts)
      .where(inArray(yachts.id, yachtIds));
    yachtsMap = Object.fromEntries(yachtRows.map((y) => [y.id, y.name]));
  }

  if (interestIds.length > 0) {
    const tagRows = await db
      .select({
        interestId: interestTags.interestId,
        id: tags.id,
        name: tags.name,
        color: tags.color,
      })
      .from(interestTags)
      .innerJoin(tags, eq(interestTags.tagId, tags.id))
      .where(inArray(interestTags.interestId, interestIds));

    for (const row of tagRows) {
      if (!tagsByInterestId[row.interestId]) tagsByInterestId[row.interestId] = [];
      tagsByInterestId[row.interestId]!.push({ id: row.id, name: row.name, color: row.color });
    }

    // Note counts per interest, for the comment-icon row affordance.
    const noteCountRows = await db
      .select({
        interestId: interestNotes.interestId,
        count: sql<number>`count(*)::int`,
      })
      .from(interestNotes)
      .where(inArray(interestNotes.interestId, interestIds))
      .groupBy(interestNotes.interestId);
    for (const row of noteCountRows) {
      notesCountByInterestId[row.interestId] = row.count;
    }
  }

  const data = (result.data as Array<Record<string, unknown>>).map((i) => {
    const primary = primaryBerthMap.get(i.id as string) ?? null;
    return {
      ...i,
      clientName: clientsMap[i.clientId as string] ?? null,
      berthId: primary?.berthId ?? null,
      berthMooringNumber: primary?.mooringNumber ?? null,
      yachtName: i.yachtId ? (yachtsMap[i.yachtId as string] ?? null) : null,
      tags: tagsByInterestId[i.id as string] ?? [],
      notesCount: notesCountByInterestId[i.id as string] ?? 0,
    };
  });

  return { data, total: result.total };
}

// ─── Get by ID ────────────────────────────────────────────────────────────────

export async function getInterestById(id: string, portId: string) {
  const interest = await db.query.interests.findFirst({
    where: eq(interests.id, id),
  });

  if (!interest || interest.portId !== portId) {
    throw new NotFoundError('Interest');
  }

  const [clientRow] = await db
    .select({ fullName: clients.fullName })
    .from(clients)
    .where(eq(clients.id, interest.clientId));

  // EOI prerequisites + interest-detail header contact actions: surface the
  // linked client's primary email/phone (and the canonical E.164 form for
  // wa.me) so the header can render Email / Call / WhatsApp buttons without
  // a second fetch, and the Documents tab can show the EOI prereq checklist.
  const [emailContact] = await db
    .select({ value: clientContacts.value })
    .from(clientContacts)
    .where(and(eq(clientContacts.clientId, interest.clientId), eq(clientContacts.channel, 'email')))
    .orderBy(desc(clientContacts.isPrimary), desc(clientContacts.updatedAt))
    .limit(1);

  const [phoneContact] = await db
    .select({ value: clientContacts.value, valueE164: clientContacts.valueE164 })
    .from(clientContacts)
    .where(
      and(
        eq(clientContacts.clientId, interest.clientId),
        inArray(clientContacts.channel, ['phone', 'whatsapp']),
      ),
    )
    .orderBy(desc(clientContacts.isPrimary), desc(clientContacts.updatedAt))
    .limit(1);

  const [addressRow] = await db
    .select({ id: clientAddresses.id })
    .from(clientAddresses)
    .where(
      and(eq(clientAddresses.clientId, interest.clientId), eq(clientAddresses.isPrimary, true)),
    )
    .limit(1);

  // Primary berth comes from the interest_berths junction (plan §3.4).
  const primaryBerth = await getPrimaryBerth(interest.id);
  const berthId = primaryBerth?.berthId ?? null;
  const berthMooringNumber = primaryBerth?.mooringNumber ?? null;

  const tagRows = await db
    .select({ id: tags.id, name: tags.name, color: tags.color })
    .from(interestTags)
    .innerJoin(tags, eq(interestTags.tagId, tags.id))
    .where(eq(interestTags.interestId, id));

  // Most-recent note preview for the Overview tab (the "do you have anything
  // outstanding on this lead?" peek). Returns the latest note's truncated
  // content + author/timestamp so the UI can render a one-line teaser.
  const [recentNote] = await db
    .select({
      id: interestNotes.id,
      content: interestNotes.content,
      authorId: interestNotes.authorId,
      createdAt: interestNotes.createdAt,
    })
    .from(interestNotes)
    .where(eq(interestNotes.interestId, id))
    .orderBy(desc(interestNotes.createdAt))
    .limit(1);

  const [{ count: notesCount } = { count: 0 }] = await db
    .select({ count: sql<number>`count(*)::int` })
    .from(interestNotes)
    .where(eq(interestNotes.interestId, id));

  // Active reminder count for the interest's bell badge. Counts reminders
  // directly linked via interestId - `pending` and `snoozed` only;
  // completed/dismissed don't surface.
  const [{ count: activeReminderCount } = { count: 0 }] = await db
    .select({ count: sql<number>`count(*)::int` })
    .from(reminders)
    .where(and(eq(reminders.interestId, id), inArray(reminders.status, ['pending', 'snoozed'])));

  return {
    ...interest,
    clientName: clientRow?.fullName ?? null,
    clientPrimaryEmail: emailContact?.value ?? null,
    clientPrimaryPhone: phoneContact?.value ?? null,
    clientPrimaryPhoneE164: phoneContact?.valueE164 ?? null,
    clientHasAddress: !!addressRow,
    berthId,
    berthMooringNumber,
    tags: tagRows,
    notesCount,
    recentNote: recentNote ?? null,
    activeReminderCount,
  };
}

// ─── Create ───────────────────────────────────────────────────────────────────

export async function createInterest(portId: string, data: CreateInterestInput, meta: AuditMeta) {
  await assertInterestFksInPort(portId, {
    clientId: data.clientId,
    berthId: data.berthId,
    yachtId: data.yachtId,
  });

  if (data.yachtId) {
    await assertYachtBelongsToClient(portId, data.yachtId, data.clientId);
  }

  const { tagIds, berthId: inputBerthId, ...interestData } = data;

  // BR-011: auto-promote leadCategory
  const resolvedLeadCategory = await resolveLeadCategory(
    data.clientId,
    data.leadCategory,
    data.yachtId,
  );

  // Per-port reminder defaults — applied only when the caller omitted
  // reminderEnabled / reminderDays. Honors the /admin/reminders page.
  const reminderConfig = await getPortReminderConfig(portId);
  const resolvedReminderEnabled = interestData.reminderEnabled ?? reminderConfig.defaultEnabled;
  const resolvedReminderDays =
    interestData.reminderDays ?? (resolvedReminderEnabled ? reminderConfig.defaultDays : null);

  const result = await withTransaction(async (tx) => {
    const [interest] = await tx
      .insert(interests)
      .values({
        portId,
        ...interestData,
        reminderEnabled: resolvedReminderEnabled,
        reminderDays: resolvedReminderDays,
        leadCategory: resolvedLeadCategory,
      })
      .returning();

    if (tagIds && tagIds.length > 0) {
      await tx
        .insert(interestTags)
        .values(tagIds.map((tagId) => ({ interestId: interest!.id, tagId })));
    }

    // Plan §3.4: when berthId is provided we materialise it as a junction
    // row inside the same transaction so an interest is never created
    // without its primary-berth link surviving rollback.
    if (inputBerthId) {
      await upsertInterestBerthTx(tx, interest!.id, inputBerthId, {
        isPrimary: true,
        isSpecificInterest: true,
        isInEoiBundle: false,
        addedBy: meta.userId,
      });
    }

    return interest!;
  });

  void createAuditLog({
    userId: meta.userId,
    portId,
    action: 'create',
    entityType: 'interest',
    entityId: result.id,
    newValue: { clientId: result.clientId, pipelineStage: result.pipelineStage },
    ipAddress: meta.ipAddress,
    userAgent: meta.userAgent,
  });

  emitToRoom(`port:${portId}`, 'interest:created', {
    interestId: result.id,
    clientId: result.clientId,
    berthId: inputBerthId ?? null,
    source: result.source ?? '',
  });

  void import('@/lib/services/webhook-dispatch').then(({ dispatchWebhookEvent }) =>
    dispatchWebhookEvent(portId, 'interest:created', {
      interestId: result.id,
      clientId: result.clientId,
    }),
  );

  return result;
}

// ─── Update ───────────────────────────────────────────────────────────────────

export async function updateInterest(
  id: string,
  portId: string,
  data: UpdateInterestInput,
  meta: AuditMeta,
) {
  const existing = await db.query.interests.findFirst({
    where: eq(interests.id, id),
  });

  if (!existing || existing.portId !== portId) {
    throw new NotFoundError('Interest');
  }

  // berthId no longer lives on the interests row - resolve current primary
  // via the junction so we know whether the caller is asking for a change.
  const currentPrimary = await getPrimaryBerth(id);
  const currentBerthId = currentPrimary?.berthId ?? null;

  await assertInterestFksInPort(portId, {
    berthId: data.berthId && data.berthId !== currentBerthId ? data.berthId : null,
    yachtId: data.yachtId && data.yachtId !== existing.yachtId ? data.yachtId : null,
  });

  if (data.yachtId && data.yachtId !== existing.yachtId) {
    await assertYachtBelongsToClient(portId, data.yachtId, existing.clientId);
  }

  // BR-011: auto-promote leadCategory if provided
  let resolvedLeadCategory = data.leadCategory;
  if ('leadCategory' in data) {
    resolvedLeadCategory = (await resolveLeadCategory(
      existing.clientId,
      data.leadCategory,
      data.yachtId ?? existing.yachtId,
    )) as typeof data.leadCategory;
  }

  // Strip berthId out of the row write - the column was removed by the
  // junction-migration. We keep the value for diff/audit purposes and
  // dispatch the junction write separately.
  const { berthId: incomingBerthId, ...rowData } = data;
  const updateData = { ...rowData, leadCategory: resolvedLeadCategory };
  const { diff } = diffEntity(
    { ...(existing as Record<string, unknown>), berthId: currentBerthId },
    { ...(updateData as Record<string, unknown>), berthId: incomingBerthId ?? currentBerthId },
  );

  const [updated] = await db
    .update(interests)
    .set({ ...updateData, updatedAt: new Date() })
    .where(and(eq(interests.id, id), eq(interests.portId, portId)))
    .returning();

  // Apply primary-berth change through the junction so the unique
  // partial index is respected and the previous primary is demoted.
  if ('berthId' in data && incomingBerthId !== currentBerthId) {
    if (incomingBerthId) {
      await upsertInterestBerth(id, incomingBerthId, {
        isPrimary: true,
        isSpecificInterest: true,
        addedBy: meta.userId,
      });
    } else if (currentBerthId) {
      await removeInterestBerth(id, currentBerthId, portId);
    }
  }

  void createAuditLog({
    userId: meta.userId,
    portId,
    action: 'update',
    entityType: 'interest',
    entityId: id,
    oldValue: diff as Record<string, unknown>,
    newValue: updateData as Record<string, unknown>,
    ipAddress: meta.ipAddress,
    userAgent: meta.userAgent,
  });

  emitToRoom(`port:${portId}`, 'interest:updated', {
    interestId: id,
    changedFields: Object.keys(diff),
  });

  return updated!;
}

// ─── Change Stage ─────────────────────────────────────────────────────────────

export async function changeInterestStage(
  id: string,
  portId: string,
  data: ChangeStageInput,
  meta: AuditMeta,
) {
  const existing = await db.query.interests.findFirst({
    where: eq(interests.id, id),
  });

  if (!existing || existing.portId !== portId) {
    throw new NotFoundError('Interest');
  }

  // Plan: yachtId required to leave stage=open
  if (existing.pipelineStage === 'open' && data.pipelineStage !== 'open' && !existing.yachtId) {
    throw new ValidationError('yachtId is required before leaving stage=open');
  }

  // Block egregious skips. The transition table allows reasonable forward
  // jumps (e.g. open → eoi_sent) while rejecting things like completed → open
  // or open → contract_signed. Same-stage no-ops are allowed.
  // Override (sales-rep manual fix) bypasses the table — the route handler
  // gates this on the `interests.override_stage` permission and requires
  // a reason, recorded in the audit log below.
  if (!data.override && !canTransitionStage(existing.pipelineStage, data.pipelineStage)) {
    throw new ValidationError(
      `Cannot move interest from "${existing.pipelineStage}" directly to "${data.pipelineStage}". Use the override option if you need to skip stages — requires a reason.`,
    );
  }
  if (data.override && (!data.reason || data.reason.trim().length < 5)) {
    throw new ValidationError(
      'Override requires a reason (min 5 chars) explaining the manual stage change.',
    );
  }

  const oldStage = existing.pipelineStage;

  const [updated] = await db
    .update(interests)
    .set({ pipelineStage: data.pipelineStage, updatedAt: new Date() })
    .where(and(eq(interests.id, id), eq(interests.portId, portId)))
    .returning();

  // BR-133: Auto-populate milestones based on stage
  const milestoneUpdates: Record<string, unknown> = {};
  if (data.pipelineStage === 'eoi_sent') milestoneUpdates.dateEoiSent = new Date();
  if (data.pipelineStage === 'eoi_signed') milestoneUpdates.dateEoiSigned = new Date();
  if (data.pipelineStage === 'deposit_10pct') milestoneUpdates.dateDepositReceived = new Date();
  if (data.pipelineStage === 'contract_sent') milestoneUpdates.dateContractSent = new Date();
  if (data.pipelineStage === 'contract_signed') milestoneUpdates.dateContractSigned = new Date();
  if (Object.keys(milestoneUpdates).length > 0) {
    await db
      .update(interests)
      .set({ ...milestoneUpdates, updatedAt: new Date() })
      .where(eq(interests.id, id));
  }

  void createAuditLog({
    userId: meta.userId,
    portId,
    action: 'update',
    entityType: 'interest',
    entityId: id,
    oldValue: { pipelineStage: oldStage },
    newValue: { pipelineStage: data.pipelineStage, reason: data.reason },
    metadata: { type: 'stage_change', reason: data.reason },
    ipAddress: meta.ipAddress,
    userAgent: meta.userAgent,
  });

  emitToRoom(`port:${portId}`, 'interest:stageChanged', {
    interestId: id,
    oldStage: oldStage ?? '',
    newStage: data.pipelineStage,
    clientName: '',
    berthNumber: '',
  });

  void import('@/lib/services/webhook-dispatch').then(({ dispatchWebhookEvent }) =>
    dispatchWebhookEvent(portId, 'interest:stageChanged', {
      interestId: id,
      oldStage: oldStage ?? null,
      newStage: data.pipelineStage,
    }),
  );

  // Fire-and-forget notification to the acting user
  void import('@/lib/services/notifications.service').then(({ createNotification }) =>
    createNotification({
      portId,
      userId: meta.userId,
      type: 'interest_stage_changed',
      title: `Interest moved to ${data.pipelineStage}`,
      description: `Interest ${id} stage changed from ${oldStage ?? 'unknown'} to ${data.pipelineStage}`,
      link: `/interests/${id}`,
      entityType: 'interest',
      entityId: id,
      dedupeKey: `interest:${id}:stage:${data.pipelineStage}`,
      cooldownMs: 300_000,
    }),
  );

  return updated!;
}

// ─── Advance Stage If Behind ─────────────────────────────────────────────────
//
// Moves an interest forward to `target` if (and only if) it is currently behind
// it in the pipeline order. Used by lifecycle events (EOI sent, EOI signed,
// deposit recorded, contract signed) so the user-visible stage tracks reality
// without overwriting a more advanced state - e.g. a late-arriving signed-EOI
// webhook on an interest that has already moved on to `contract_sent` is a
// no-op rather than a regression.
//
// Returns true when the stage was changed.
export async function advanceStageIfBehind(
  interestId: string,
  portId: string,
  target: PipelineStage,
  meta: AuditMeta,
  reason?: string,
): Promise<boolean> {
  const existing = await db.query.interests.findFirst({
    where: and(eq(interests.id, interestId), eq(interests.portId, portId)),
  });
  if (!existing) return false;

  const currentIdx = PIPELINE_STAGES.indexOf(existing.pipelineStage as PipelineStage);
  const targetIdx = PIPELINE_STAGES.indexOf(target);
  if (currentIdx === -1 || targetIdx === -1 || currentIdx >= targetIdx) {
    return false;
  }

  // yachtId gate: changeInterestStage requires a yacht before leaving `open`.
  // EOI events imply a yacht is in the picture, but if the data is missing we
  // bail rather than throw - the EOI itself shouldn't fail because of this.
  if (existing.pipelineStage === 'open' && !existing.yachtId) {
    return false;
  }

  await changeInterestStage(interestId, portId, { pipelineStage: target, reason }, meta);
  return true;
}

// ─── Set Outcome (Won / Lost) ────────────────────────────────────────────────
//
// Records a terminal outcome for the interest and moves the pipelineStage to
// `completed` so the funnel/kanban reflect the final state. The outcome
// distinguishes won deals (they made it through) from lost variants - funnel
// math and reports key off the `outcome` column to compute true conversion.
//
// Both the stage advance and the outcome write happen in one transaction so
// the timeline doesn't end up showing one without the other.
export async function setInterestOutcome(
  id: string,
  portId: string,
  data: SetOutcomeInput,
  meta: AuditMeta,
) {
  const existing = await db.query.interests.findFirst({
    where: and(eq(interests.id, id), eq(interests.portId, portId)),
  });
  if (!existing) throw new NotFoundError('Interest');

  const oldOutcome = existing.outcome;
  const oldStage = existing.pipelineStage;

  const now = new Date();
  await db
    .update(interests)
    .set({
      outcome: data.outcome,
      outcomeReason: data.reason ?? null,
      outcomeAt: now,
      pipelineStage: 'completed',
      updatedAt: now,
    })
    .where(and(eq(interests.id, id), eq(interests.portId, portId)));

  void createAuditLog({
    userId: meta.userId,
    portId,
    action: 'update',
    entityType: 'interest',
    entityId: id,
    oldValue: { outcome: oldOutcome, pipelineStage: oldStage },
    newValue: { outcome: data.outcome, pipelineStage: 'completed', reason: data.reason },
    metadata: { type: 'outcome_set' },
    ipAddress: meta.ipAddress,
    userAgent: meta.userAgent,
  });

  emitToRoom(`port:${portId}`, 'interest:outcomeSet', {
    interestId: id,
    outcome: data.outcome,
    oldStage,
  });

  return { ok: true as const };
}

// Clears a terminal outcome and reopens the interest. Used when an outcome
// was set in error or a "lost" deal comes back to life.
export async function clearInterestOutcome(
  id: string,
  portId: string,
  data: ClearOutcomeInput,
  meta: AuditMeta,
) {
  const existing = await db.query.interests.findFirst({
    where: and(eq(interests.id, id), eq(interests.portId, portId)),
  });
  if (!existing) throw new NotFoundError('Interest');
  if (!existing.outcome) {
    throw new ValidationError('Interest has no outcome to clear');
  }

  const reopenStage = data.reopenStage ?? 'in_communication';
  const now = new Date();
  await db
    .update(interests)
    .set({
      outcome: null,
      outcomeReason: null,
      outcomeAt: null,
      pipelineStage: reopenStage,
      updatedAt: now,
    })
    .where(and(eq(interests.id, id), eq(interests.portId, portId)));

  void createAuditLog({
    userId: meta.userId,
    portId,
    action: 'update',
    entityType: 'interest',
    entityId: id,
    oldValue: { outcome: existing.outcome, pipelineStage: existing.pipelineStage },
    newValue: { outcome: null, pipelineStage: reopenStage },
    metadata: { type: 'outcome_cleared' },
    ipAddress: meta.ipAddress,
    userAgent: meta.userAgent,
  });

  emitToRoom(`port:${portId}`, 'interest:outcomeCleared', { interestId: id });

  return { ok: true as const };
}

// ─── Archive / Restore ────────────────────────────────────────────────────────

export async function archiveInterest(id: string, portId: string, meta: AuditMeta) {
  const existing = await db.query.interests.findFirst({
    where: eq(interests.id, id),
  });

  if (!existing || existing.portId !== portId) {
    throw new NotFoundError('Interest');
  }

  // BR-014: Block archive if pending EOI/contract
  if (existing.eoiStatus === 'waiting_for_signatures' || existing.contractStatus === 'pending') {
    throw new ConflictError(
      'Cannot archive interest with pending documents. Cancel documents first.',
    );
  }

  await softDelete(interests, interests.id, id);

  void createAuditLog({
    userId: meta.userId,
    portId,
    action: 'archive',
    entityType: 'interest',
    entityId: id,
    ipAddress: meta.ipAddress,
    userAgent: meta.userAgent,
  });

  emitToRoom(`port:${portId}`, 'interest:archived', { interestId: id });
}

export async function restoreInterest(id: string, portId: string, meta: AuditMeta) {
  const existing = await db.query.interests.findFirst({
    where: eq(interests.id, id),
  });

  if (!existing || existing.portId !== portId) {
    throw new NotFoundError('Interest');
  }

  await restore(interests, interests.id, id);

  void createAuditLog({
    userId: meta.userId,
    portId,
    action: 'restore',
    entityType: 'interest',
    entityId: id,
    ipAddress: meta.ipAddress,
    userAgent: meta.userAgent,
  });

  emitToRoom(`port:${portId}`, 'interest:updated', { interestId: id, changedFields: [] });
}

// ─── Set Tags ─────────────────────────────────────────────────────────────────

export async function setInterestTags(
  id: string,
  portId: string,
  tagIds: string[],
  meta: AuditMeta,
) {
  const existing = await db.query.interests.findFirst({
    where: eq(interests.id, id),
  });

  if (!existing || existing.portId !== portId) {
    throw new NotFoundError('Interest');
  }

  const result = await setEntityTags({
    joinTable: interestTags,
    entityColumn: interestTags.interestId,
    tagColumn: interestTags.tagId,
    entityId: id,
    portId,
    tagIds,
    meta,
    entityType: 'interest',
  });

  return { interestId: result.entityId, tagIds: result.tagIds };
}

// ─── Link / Unlink Berth ──────────────────────────────────────────────────────

export async function linkBerth(id: string, portId: string, berthId: string, meta: AuditMeta) {
  const existing = await db.query.interests.findFirst({
    where: eq(interests.id, id),
  });

  if (!existing || existing.portId !== portId) {
    throw new NotFoundError('Interest');
  }

  await assertInterestFksInPort(portId, { berthId });

  const previousPrimary = await getPrimaryBerth(id);
  const oldBerthId = previousPrimary?.berthId ?? null;

  await upsertInterestBerth(id, berthId, {
    isPrimary: true,
    isSpecificInterest: true,
    addedBy: meta.userId,
  });

  // Touch updatedAt so list/sort surfaces still reflect the change.
  const [updated] = await db
    .update(interests)
    .set({ updatedAt: new Date() })
    .where(and(eq(interests.id, id), eq(interests.portId, portId)))
    .returning();

  void createAuditLog({
    userId: meta.userId,
    portId,
    action: 'update',
    entityType: 'interest',
    entityId: id,
    oldValue: { berthId: oldBerthId },
    newValue: { berthId },
    metadata: { type: 'berth_linked' },
    ipAddress: meta.ipAddress,
    userAgent: meta.userAgent,
  });

  emitToRoom(`port:${portId}`, 'interest:berthLinked', { interestId: id, berthId });

  void import('@/lib/services/webhook-dispatch').then(({ dispatchWebhookEvent }) =>
    dispatchWebhookEvent(portId, 'interest:berthLinked', { interestId: id, berthId }),
  );

  return updated!;
}

export async function unlinkBerth(id: string, portId: string, meta: AuditMeta) {
  const existing = await db.query.interests.findFirst({
    where: eq(interests.id, id),
  });

  if (!existing || existing.portId !== portId) {
    throw new NotFoundError('Interest');
  }

  const previousPrimary = await getPrimaryBerth(id);
  const oldBerthId = previousPrimary?.berthId ?? null;

  if (oldBerthId) {
    await removeInterestBerth(id, oldBerthId, portId);
  }

  const [updated] = await db
    .update(interests)
    .set({ updatedAt: new Date() })
    .where(and(eq(interests.id, id), eq(interests.portId, portId)))
    .returning();

  void createAuditLog({
    userId: meta.userId,
    portId,
    action: 'update',
    entityType: 'interest',
    entityId: id,
    oldValue: { berthId: oldBerthId },
    newValue: { berthId: null },
    metadata: { type: 'berth_unlinked' },
    ipAddress: meta.ipAddress,
    userAgent: meta.userAgent,
  });

  emitToRoom(`port:${portId}`, 'interest:berthUnlinked', {
    interestId: id,
    berthId: oldBerthId ?? '',
  });

  return updated!;
}

// ─── Stage Counts (for board) ────────────────────────────────────────────────

export async function getInterestStageCounts(portId: string) {
  const rows = await db
    .select({ stage: interests.pipelineStage, count: sql<number>`count(*)::int` })
    .from(interests)
    .where(and(eq(interests.portId, portId), isNull(interests.archivedAt)))
    .groupBy(interests.pipelineStage);
  return Object.fromEntries(rows.map((r) => [r.stage, r.count]));
}