import type { SerializedProjectCommand } from "./project-command.model.js";
import {
  assertCircuitInsertProjectCommand,
  circuitInsertCommandType,
  circuitStructureCommandSchemaVersion,
  type CircuitSnapshot,
} from "./circuit-structure-project-command.model.js";

export const circuitDeviceRowMoveCommandType =
  "circuit-device-row.move" as const;
export const circuitDeviceRowMoveWithNewCircuitCommandType =
  "circuit-device-row.move-with-new-circuit" as const;
export const circuitDeviceRowMoveCommandSchemaVersion = 1 as const;

export interface CircuitDeviceRowMoveAssignment {
  rowId: string;
  expectedCircuitId: string;
  expectedSortOrder: number;
  targetCircuitId: string;
  targetSortOrder: number;
}

export interface CircuitDeviceRowMoveCommandPayload {
  moves: CircuitDeviceRowMoveAssignment[];
}

export interface CircuitDeviceRowMoveProjectCommand
  extends SerializedProjectCommand<CircuitDeviceRowMoveCommandPayload> {
  schemaVersion: typeof circuitDeviceRowMoveCommandSchemaVersion;
  type: typeof circuitDeviceRowMoveCommandType;
}

export type CircuitDeviceRowMoveTargetCircuitAction =
  | "create"
  | "delete";

export interface CircuitDeviceRowMoveWithNewCircuitCommandPayload {
  targetCircuitAction: CircuitDeviceRowMoveTargetCircuitAction;
  targetCircuit: CircuitSnapshot;
  moves: CircuitDeviceRowMoveAssignment[];
}

export interface CircuitDeviceRowMoveWithNewCircuitProjectCommand
  extends SerializedProjectCommand<CircuitDeviceRowMoveWithNewCircuitCommandPayload> {
  schemaVersion: typeof circuitDeviceRowMoveCommandSchemaVersion;
  type: typeof circuitDeviceRowMoveWithNewCircuitCommandType;
}

export type CircuitDeviceRowMoveHistoryProjectCommand =
  | CircuitDeviceRowMoveProjectCommand
  | CircuitDeviceRowMoveWithNewCircuitProjectCommand;

export function createCircuitDeviceRowMoveProjectCommand(
  moves: CircuitDeviceRowMoveAssignment[]
): CircuitDeviceRowMoveProjectCommand {
  const command: CircuitDeviceRowMoveProjectCommand = {
    schemaVersion: circuitDeviceRowMoveCommandSchemaVersion,
    type: circuitDeviceRowMoveCommandType,
    payload: { moves },
  };
  assertCircuitDeviceRowMoveProjectCommand(command);
  return command;
}

export function createCircuitDeviceRowMoveWithNewCircuitProjectCommand(
  targetCircuitAction: CircuitDeviceRowMoveTargetCircuitAction,
  targetCircuit: CircuitSnapshot,
  moves: CircuitDeviceRowMoveAssignment[]
): CircuitDeviceRowMoveWithNewCircuitProjectCommand {
  const command: CircuitDeviceRowMoveWithNewCircuitProjectCommand = {
    schemaVersion: circuitDeviceRowMoveCommandSchemaVersion,
    type: circuitDeviceRowMoveWithNewCircuitCommandType,
    payload: {
      targetCircuitAction,
      targetCircuit,
      moves,
    },
  };
  assertCircuitDeviceRowMoveWithNewCircuitProjectCommand(command);
  return command;
}

export function assertCircuitDeviceRowMoveProjectCommand(
  command: SerializedProjectCommand<unknown>
): asserts command is CircuitDeviceRowMoveProjectCommand {
  if (
    command.schemaVersion !== circuitDeviceRowMoveCommandSchemaVersion ||
    command.type !== circuitDeviceRowMoveCommandType
  ) {
    throw new Error("Unsupported circuit device-row move command.");
  }
  if (!isPlainObject(command.payload)) {
    throw new Error(
      "Circuit device-row move payload must be an object."
    );
  }
  const moves = command.payload.moves;
  if (!Array.isArray(moves) || moves.length === 0) {
    throw new Error(
      "Circuit device-row move command requires at least one move."
    );
  }

  const rowIds = new Set<string>();
  for (const move of moves) {
    if (!isPlainObject(move)) {
      throw new Error(
        "Circuit device-row move command contains an invalid move."
      );
    }
    assertNonEmptyString(move.rowId, "rowId");
    assertNonEmptyString(
      move.expectedCircuitId,
      "expectedCircuitId"
    );
    assertFiniteNumber(
      move.expectedSortOrder,
      "expectedSortOrder"
    );
    assertNonEmptyString(move.targetCircuitId, "targetCircuitId");
    assertFiniteNumber(move.targetSortOrder, "targetSortOrder");
    if (rowIds.has(move.rowId)) {
      throw new Error(
        "Circuit device-row move command contains duplicate row ids."
      );
    }
    if (
      move.expectedCircuitId === move.targetCircuitId &&
      move.expectedSortOrder === move.targetSortOrder
    ) {
      throw new Error(
        "Circuit device-row move command contains a no-op move."
      );
    }

    rowIds.add(move.rowId);
  }
}

export function assertCircuitDeviceRowMoveWithNewCircuitProjectCommand(
  command: SerializedProjectCommand<unknown>
): asserts command is CircuitDeviceRowMoveWithNewCircuitProjectCommand {
  if (
    command.schemaVersion !== circuitDeviceRowMoveCommandSchemaVersion ||
    command.type !== circuitDeviceRowMoveWithNewCircuitCommandType
  ) {
    throw new Error(
      "Unsupported circuit device-row move-with-new-circuit command."
    );
  }
  if (!isPlainObject(command.payload)) {
    throw new Error(
      "Circuit device-row move-with-new-circuit payload must be an object."
    );
  }
  const { targetCircuitAction, targetCircuit, moves } =
    command.payload;
  if (
    targetCircuitAction !== "create" &&
    targetCircuitAction !== "delete"
  ) {
    throw new Error(
      "Target circuit action must be create or delete."
    );
  }

  assertCircuitInsertProjectCommand({
    schemaVersion: circuitStructureCommandSchemaVersion,
    type: circuitInsertCommandType,
    payload: { circuit: targetCircuit },
  });
  const validatedTargetCircuit = targetCircuit as CircuitSnapshot;
  if (
    validatedTargetCircuit.isReserve !== true ||
    validatedTargetCircuit.deviceRows.length !== 0
  ) {
    throw new Error(
      "Move target circuit snapshot must describe an empty reserve circuit."
    );
  }

  assertCircuitDeviceRowMoveProjectCommand({
    schemaVersion: circuitDeviceRowMoveCommandSchemaVersion,
    type: circuitDeviceRowMoveCommandType,
    payload: { moves },
  });
  const validatedMoves = moves as CircuitDeviceRowMoveAssignment[];
  for (const move of validatedMoves) {
    if (
      targetCircuitAction === "create" &&
      (move.expectedCircuitId === validatedTargetCircuit.id ||
        move.targetCircuitId !== validatedTargetCircuit.id)
    ) {
      throw new Error(
        "Create-target moves must move rows into the new circuit."
      );
    }
    if (
      targetCircuitAction === "delete" &&
      (move.expectedCircuitId !== validatedTargetCircuit.id ||
        move.targetCircuitId === validatedTargetCircuit.id)
    ) {
      throw new Error(
        "Delete-target moves must move rows out of the created circuit."
      );
    }
  }
}

function assertNonEmptyString(
  value: unknown,
  field: string
): asserts value is string {
  if (typeof value !== "string" || !value.trim()) {
    throw new Error(`${field} must be a non-empty string.`);
  }
}

function assertFiniteNumber(
  value: unknown,
  field: string
): asserts value is number {
  if (typeof value !== "number" || !Number.isFinite(value)) {
    throw new Error(`${field} must be a finite number.`);
  }
}

function isPlainObject(value: unknown): value is Record<string, unknown> {
  return value !== null && typeof value === "object" && !Array.isArray(value);
}