mathsteps-experimental-fork/dist/es/lib/simplifyExpression/stepEvaluationCoreNextStepOptionsHelper.js

Step by step math solutions. Experimental Fork

import math from '../index.js';
import { getCrossMultiplication } from '../kemuEquation/Special-CrossMultiplication.js';
import { areExpressionEqual } from '../newServices/expressionEqualsAndNormalization.js';
import { myNodeToString } from '../newServices/nodeServices/myNodeToString.js';
import { findAllOperationsThatCanBeRemoved } from '../newServices/nodeServices/termRemovalOperations.js';
import { getValidStepEqCache } from './equationCache.js';
import { mistakeSearches } from './mistakes/regexPemdasMistakes.js';
import { getAddRemoveTermTypeBasedOnOp } from '../types/changeType/changeAndMistakeUtils.js';
import { ChangeTypes } from '../types/changeType/ChangeTypes.js';
import { filterUniqueValues } from '../util/arrayUtils.js';
import { cleanString } from '../util/cleanString.js';
import { RGIntOrDecimal } from '../util/regex.js';
import { parseText } from '../newServices/nodeServices/parseText.js';

const { SIMPLIFY_ARITHMETIC__ADD, SIMPLIFY_ARITHMETIC__SUBTRACT } = ChangeTypes;
const expressionEquals = (exp0, exp1) => areExpressionEqual(exp0, exp1, getValidStepEqCache());
function _normalizeExpressionForCountingSubtractions(expr) {
  return expr.replace(/\+-/g, "-").replace(/-\+/g, "-").replace(/--/g, "+").replace(/^-/, "");
}
function _correctSimplifyAdditionToSubtraction(steps) {
  steps.forEach((step) => {
    if (step.changeType === SIMPLIFY_ARITHMETIC__ADD && step.from.includes("-")) {
      const fromRaw = _normalizeExpressionForCountingSubtractions(step.from);
      const toRaw = _normalizeExpressionForCountingSubtractions(step.to);
      const fromMinusCount = [...fromRaw.matchAll(/-/g)].length;
      const toMinusCount = [...toRaw.matchAll(/-/g)].length;
      if (toMinusCount < fromMinusCount) {
        step.changeType = SIMPLIFY_ARITHMETIC__SUBTRACT;
      }
    }
  });
  const newAvailableChangeTypes = steps.filter((step) => !step?.isMistake).map((step) => step?.changeType);
  steps.forEach((step) => {
    step.availableChangeTypes = newAvailableChangeTypes;
  });
}
function _convertRawStepsToProcessedStep(steps) {
  const processedStepsSet = /* @__PURE__ */ new Set();
  return steps.filter((step) => step.to).flatMap((step) => step.to.map((toStr) => ({
    ...step,
    availableChangeTypes: steps.filter((step2) => !step2?.isMistake).map((step2) => step2?.changeType),
    // TODO remove availableChangeTypes from here? We add it again in _addAllAvailableChangeTypesToEachStep
    to: cleanString(toStr),
    from: cleanString(step.from)
  }))).filter((step) => !processedStepsSet.has(step.to) && processedStepsSet.add(step.to)).filter((step) => step.to !== step.from);
}
function _addAllAvailableChangeTypesToEachStep(steps) {
  const availableChangeTypes = steps.filter((step) => !step?.isMistake).map((step) => step?.changeType);
  steps.forEach((step) => {
    step.availableChangeTypes = availableChangeTypes;
  });
}
function _addAllPossibleCorrectTosToEachStep(steps) {
  const allPossibleCorrectTos = steps.filter((step) => !step.isMistake).map((step) => step.to);
  steps.forEach((step) => {
    step.allPossibleCorrectTos = allPossibleCorrectTos;
  });
}
function findAllNextStepOptions(userStep_, neededForEquations, { getMistakes = true, isDebugMode = false } = {}) {
  let userStep = typeof userStep_ === "string" ? myNodeToString(parseText(userStep_)) : myNodeToString(userStep_);
  userStep = userStep.replaceAll(/\b0[a-z]\b/gmi, "0").replaceAll(/\b0\*[a-z]\b/gmi, "0");
  const potentialSteps = [];
  math.simplifyExpression({
    expressionAsText: userStep,
    isDebugMode,
    getMistakes,
    getAllNextStepPossibilities: true,
    onStepCb: (step) => potentialSteps.push(step)
  });
  const processedSteps = filterUniqueValues(_convertRawStepsToProcessedStep(potentialSteps), (itemA, itemB) => expressionEquals(itemA.to, itemB.to));
  if (neededForEquations?.otherSide && neededForEquations?.history) {
    const removedDepth = neededForEquations.history.filter((step) => step.removeNumberOp).map((step) => step.removeNumberOp).length;
    const addedDepth = neededForEquations.history.filter((step) => step.addedNumOp).map((step) => step.addedNumOp).length;
    if (neededForEquations.history.length <= 1 && removedDepth === 0 && addedDepth === 0) {
      const crossMultiplied = getCrossMultiplication(userStep, neededForEquations.otherSide);
      if (crossMultiplied) {
        processedSteps.push({ from: userStep, to: myNodeToString(crossMultiplied.crossRight), changeType: "EQ_CROSS_MULTIPLY", isMistake: false, availableChangeTypes: ["EQ_CROSS_MULTIPLY"] });
        processedSteps.push({ from: userStep, to: myNodeToString(crossMultiplied.crossLeft), changeType: "EQ_CROSS_MULTIPLY", isMistake: false, availableChangeTypes: ["EQ_CROSS_MULTIPLY"] });
      }
    }
    if (neededForEquations.history.length <= 2 && removedDepth === 0 && addedDepth === 0) {
      const hasSingleNegative = (str) => (str.match(/-/gmi)?.length || 0) === 1;
      const hasVariable = (str) => (str.match(/[a-z]/gmi)?.length || 0) === 1;
      const hasNumber = (str) => (str.match(RGIntOrDecimal)?.length || 0) === 1;
      const thisSideIsVariableAndNegative = hasSingleNegative(userStep) && hasVariable(userStep);
      const thisSideIsNumberAndNegative = hasSingleNegative(userStep) && hasNumber(userStep);
      const otherSideIsVariableAndNegative = hasSingleNegative(neededForEquations.otherSide) && hasVariable(neededForEquations.otherSide);
      const otherSideIsNumberAndNegative = hasSingleNegative(neededForEquations.otherSide) && hasNumber(neededForEquations.otherSide);
      if (thisSideIsVariableAndNegative && otherSideIsNumberAndNegative || otherSideIsVariableAndNegative && thisSideIsNumberAndNegative) {
        processedSteps.push({
          from: userStep,
          to: `(${userStep}) * -1`,
          changeType: "EQ_MULTIPLY_BOTH_SIDES_BY_NEGATIVE_ONE",
          isMistake: false,
          availableChangeTypes: ["EQ_MULTIPLY_BOTH_SIDES_BY_NEGATIVE_ONE"]
        });
      }
    }
    if (removedDepth < 2 && addedDepth < 1) {
      processedSteps.push(...findAllOperationsThatCanBeRemoved(userStep, neededForEquations.history));
    }
    if (removedDepth < 1 && addedDepth < 2) {
      let makeAddedFn = function(expression0, otherSide, history) {
        const steps = findAllOperationsThatCanBeRemoved(otherSide, history, { isAdded: true });
        const removedNumOps = steps.map((step) => step.removeNumberOp).filter((removedNumOp) => removedNumOp !== void 0);
        const newExpressions = removedNumOps.map((removedNumOp) => {
          return {
            from: expression0,
            to: `(${expression0}) ${removedNumOp.op} ${removedNumOp.number}`,
            removeNumberOp: void 0,
            addedNumOp: removedNumOp,
            changeType: getAddRemoveTermTypeBasedOnOp(removedNumOp.op, "add"),
            availableChangeTypes: ["EQ_ADD_TERM"],
            isMistake: false
          };
        });
        return newExpressions;
      };
      processedSteps.push(...makeAddedFn(userStep, neededForEquations.otherSide, neededForEquations.history));
    }
  }
  if (!neededForEquations?.otherSide) {
    const manualMistakes = mistakeSearches(userStep);
    processedSteps.push(...manualMistakes);
  }
  _addAllAvailableChangeTypesToEachStep(processedSteps);
  _addAllPossibleCorrectTosToEachStep(processedSteps);
  _correctSimplifyAdditionToSubtraction(processedSteps);
  return processedSteps;
}

export { findAllNextStepOptions };