import type { CircuitGroupCategory } from "../../shared/constants/circuit-group.js";
import {
  formatCircuitGroupPrefix,
  getNextGroupedCircuitIdentifier,
  parseGroupedEquipmentIdentifier,
} from "./circuit-group-numbering.js";

export interface CircuitMoveGroupIdentity {
  id: string;
  category: CircuitGroupCategory;
  groupNumber: number;
  prefix: string;
}

export interface CircuitGroupMovePlan {
  circuitId: string;
  circuitListId: string;
  expectedSectionId: string;
  targetSectionId: string;
  expectedEquipmentIdentifier: string;
  targetEquipmentIdentifier: string;
  expectedSortOrder: number;
  targetSortOrder: number;
}

export function createCircuitGroupMovePlan(input: {
  circuit: {
    id: string;
    circuitListId: string;
    sectionId: string;
    equipmentIdentifier: string;
    sortOrder: number;
  };
  sourceGroup: CircuitMoveGroupIdentity;
  targetGroup: CircuitMoveGroupIdentity;
  targetCircuitEquipmentIdentifiers: Iterable<string>;
  targetSortOrder: number;
}): CircuitGroupMovePlan {
  assertGroupIdentity(input.sourceGroup);
  assertGroupIdentity(input.targetGroup);
  if (
    input.sourceGroup.id === input.targetGroup.id ||
    input.sourceGroup.category !== input.targetGroup.category
  ) {
    throw new Error(
      "Circuits can move only between different groups of the same category."
    );
  }
  if (
    input.circuit.sectionId !== input.sourceGroup.id ||
    !input.circuit.id.trim() ||
    !input.circuit.circuitListId.trim() ||
    !Number.isFinite(input.circuit.sortOrder) ||
    !Number.isFinite(input.targetSortOrder)
  ) {
    throw new Error("Circuit move source or target position is invalid.");
  }
  const parsed = parseGroupedEquipmentIdentifier(
    input.circuit.equipmentIdentifier
  );
  if (
    parsed?.kind !== "circuit" ||
    parsed.category !== input.sourceGroup.category ||
    parsed.groupNumber !== input.sourceGroup.groupNumber
  ) {
    throw new Error("Circuit BMK does not match its source group.");
  }

  return {
    circuitId: input.circuit.id,
    circuitListId: input.circuit.circuitListId,
    expectedSectionId: input.sourceGroup.id,
    targetSectionId: input.targetGroup.id,
    expectedEquipmentIdentifier:
      input.circuit.equipmentIdentifier,
    targetEquipmentIdentifier:
      getNextGroupedCircuitIdentifier(
        input.targetGroup.category,
        input.targetGroup.groupNumber,
        input.targetCircuitEquipmentIdentifiers
      ),
    expectedSortOrder: input.circuit.sortOrder,
    targetSortOrder: input.targetSortOrder,
  };
}

function assertGroupIdentity(group: CircuitMoveGroupIdentity) {
  if (
    !group.id.trim() ||
    !Number.isInteger(group.groupNumber) ||
    group.groupNumber < 1 ||
    group.prefix !==
      formatCircuitGroupPrefix(group.category, group.groupNumber)
  ) {
    throw new Error("Circuit move group identity is invalid.");
  }
}