import { err, ok, type CommandContext } from "@tailor-platform/erp-kit/core";
import type { Transaction } from "../generated/kysely-tailordb";
import { deriveWorkdayBlocks, persistWorkdayCalculation } from "../lib/_deriveCalculatedBlocks";
import type { ResolveWorkRuleQueries } from "../lib/_resolveWorkRule";
import { NoReportedBlocksError } from "../lib/errors.generated";
import type { TimeClassificationStrategy } from "../lib/timeClassificationStrategy";

export interface CalculateTimeBlocksInput {
  assignmentId: string;
  workDate: Date;
}

/**
 * Function: calculateTimeBlocks
 * Description: Derives/refreshes CalculatedTimeBlocks for an Assignment and workday from the
 * current (non-superseded) ReportedTimeBlocks, applying the work-rules effective on that date.
 *
 * The WorkRule is resolved through the workforce context (Assignment → WorkerEmployment /
 * Position, injected queries): the WorkRuleAssignment in force on workDate wins by
 * most-specific target (WORKER > POSITION > JOB_PROFILE > EMPLOYMENT_TYPE > WORK_REGIME), and
 * the WorkRule generation effective on workDate is applied (ADR-013, ADR-015). Reported
 * intervals are decomposed into categorized spans (regular / overtime / late-night /
 * holiday) with rounding, break deduction, the daily overtime threshold, the night window,
 * and CompanyHoliday classification; every span records calculationTagKeys and
 * sourceReportedBlockIds for audit (issue #7). After regeneration, covering OPEN Timecards
 * have their denormalized category totals refreshed.
 */
export async function run(
  db: Transaction,
  input: CalculateTimeBlocksInput,
  ctx: CommandContext,
  workforceQueries: ResolveWorkRuleQueries,
  strategy?: TimeClassificationStrategy,
) {
  const derived = await deriveWorkdayBlocks(db, workforceQueries, input, ctx, strategy);
  if (!derived.ok) {
    return derived;
  }
  if (!derived.value.hasReportedBlocks) {
    return err(new NoReportedBlocksError(`${input.assignmentId}:${input.workDate.toISOString()}`));
  }

  const calculatedTimeBlocks = await persistWorkdayCalculation(
    db,
    input.assignmentId,
    input.workDate,
    derived.value.rows,
  );

  return ok({ calculatedTimeBlocks });
}