import { err, ok, type CommandContext } from "@tailor-platform/erp-kit/core";
import type { Transaction } from "../generated/kysely-tailordb";
import {
  DuplicateLabelNameError,
  InvalidNameError,
  LabelNotFoundError,
} from "../lib/errors.generated";

export interface UpdatePipelineLabelInput {
  labelId: string;
  name?: string;
  color?: string | null;
  description?: string | null;
}

const LABEL_OWN_KEYS = new Set(["labelId", "name", "color", "description"]);

// Module-managed PipelineLabel columns that must never be writable through the
// extension-field pass-through.
const LABEL_RESERVED_KEYS = new Set(["id", "pipelineId", "createdAt", "updatedAt"]);

export async function run<CF extends Record<string, unknown>>(
  db: Transaction,
  input: UpdatePipelineLabelInput & Partial<CF>,
  ctx: CommandContext,
) {
  void ctx;

  // Consumer extension fields (declared via defineModule's pipelineLabel.fields)
  // pass through to the update untouched — except reserved model columns.
  const customFields: Record<string, unknown> = {};
  for (const [key, value] of Object.entries(input as Record<string, unknown>)) {
    if (!LABEL_OWN_KEYS.has(key) && !LABEL_RESERVED_KEYS.has(key)) {
      customFields[key] = value;
    }
  }

  const label = await db
    .selectFrom("PipelineLabel")
    .selectAll()
    .where("id", "=", input.labelId)
    .forUpdate()
    .executeTakeFirst();

  if (!label) {
    return err(new LabelNotFoundError(input.labelId));
  }

  if (input.name !== undefined) {
    if (!input.name.trim()) {
      return err(new InvalidNameError(input.name));
    }

    if (input.name !== label.name) {
      const duplicate = await db
        .selectFrom("PipelineLabel")
        .selectAll()
        .where("pipelineId", "=", label.pipelineId)
        .where("name", "=", input.name)
        .executeTakeFirst();

      if (duplicate && duplicate.id !== label.id) {
        return err(new DuplicateLabelNameError(input.name));
      }
    }
  }

  const update: Record<string, unknown> = {
    ...customFields,
    updatedAt: new Date(),
  };

  if (input.name !== undefined) update.name = input.name;
  if (input.color !== undefined) update.color = input.color;
  if (input.description !== undefined) update.description = input.description;

  const updatedLabel = await db
    .updateTable("PipelineLabel")
    .set(update)
    .where("id", "=", input.labelId)
    .returningAll()
    .executeTakeFirst();

  return ok({ label: updatedLabel ?? { ...label, ...update } });
}