web: Reorganize into frontend/backend

web/frontend/src/core/Operations/busOps.test.ts

@@ -0,0 +1,71 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { changeBusData, createBus, deleteBus, renameBus } from "./busOps";
+import assert from "node:assert";
+import { TEST_DATA_1 } from "../Data/fixtures.test";
+
+test("createBus", () => {
+  const newScenario = createBus(TEST_DATA_1);
+  assert.deepEqual(Object.keys(newScenario.Buses), ["b1", "b2", "b3", "b4"]);
+});
+
+test("changeBusData", () => {
+  let scenario = TEST_DATA_1;
+  let err = null;
+
+  [scenario, err] = changeBusData("b1", "Load (MW) 00:00", "99", scenario);
+  assert.equal(err, null);
+  [scenario, err] = changeBusData("b1", "Load (MW) 03:00", "99", scenario);
+  assert.equal(err, null);
+
+  [scenario, err] = changeBusData("b3", "Load (MW) 04:00", "99", scenario);
+  assert.equal(err, null);
+
+  assert.deepEqual(scenario.Buses, {
+    b1: { "Load (MW)": [99, 34.38835, 33.45083, 99, 33.25044] },
+    b2: { "Load (MW)": [14.03739, 13.48563, 13.11797, 12.9009, 13.03939] },
+    b3: { "Load (MW)": [27.3729, 26.29698, 25.58005, 25.15675, 99] },
+  });
+});
+
+test("changeBusData with invalid numbers", () => {
+  let [, err] = changeBusData("b1", "Load (MW) 00:00", "xx", TEST_DATA_1);
+  assert(err !== null);
+  assert.equal(err.message, '"xx" is not a valid number');
+});
+
+test("deleteBus", () => {
+  let scenario = TEST_DATA_1;
+  scenario = deleteBus("b2", scenario);
+  assert.deepEqual(scenario.Buses, {
+    b1: { "Load (MW)": [35.79534, 34.38835, 33.45083, 32.89729, 33.25044] },
+    b3: { "Load (MW)": [27.3729, 26.29698, 25.58005, 25.15675, 25.4268] },
+  });
+});
+
+test("renameBus", () => {
+  let [scenario, err] = renameBus("b1", "b99", TEST_DATA_1);
+  assert(err === null);
+  assert.deepEqual(scenario.Buses, {
+    b99: { "Load (MW)": [35.79534, 34.38835, 33.45083, 32.89729, 33.25044] },
+    b2: { "Load (MW)": [14.03739, 13.48563, 13.11797, 12.9009, 13.03939] },
+    b3: { "Load (MW)": [27.3729, 26.29698, 25.58005, 25.15675, 25.4268] },
+  });
+  assert.deepEqual(scenario.Generators["pu1"], {
+    Bus: "b99",
+    Type: "Profiled",
+    "Cost ($/MW)": 12.5,
+    "Maximum power (MW)": [10, 12, 13, 15, 20],
+    "Minimum power (MW)": [0, 0, 0, 0, 0],
+  });
+});
+
+test("renameBus with duplicated name", () => {
+  let [, err] = renameBus("b3", "b1", TEST_DATA_1);
+  assert(err != null);
+  assert.equal(err.message, `b1 already exists`);
+});

web/frontend/src/core/Operations/busOps.ts

@@ -0,0 +1,87 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { Buses } from "../Data/fixtures";
+import { ValidationError } from "../Data/validate";
+import { generateTimeslots } from "../../components/Common/Forms/DataTable";
+import {
+  changeData,
+  generateUniqueName,
+  renameItemInObject,
+} from "./commonOps";
+import { BusesColumnSpec } from "../../components/CaseBuilder/Buses";
+import { UnitCommitmentScenario } from "../Data/types";
+
+export const createBus = (scenario: UnitCommitmentScenario) => {
+  const name = generateUniqueName(scenario.Buses, "b");
+  const timeslots = generateTimeslots(scenario);
+  return {
+    ...scenario,
+    Buses: {
+      ...scenario.Buses,
+      [name]: {
+        "Load (MW)": Array(timeslots.length).fill(0),
+      },
+    },
+  };
+};
+
+export const changeBusData = (
+  bus: string,
+  field: string,
+  newValueStr: string,
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const [newBus, err] = changeData(
+    field,
+    newValueStr,
+    scenario.Buses[bus]!,
+    BusesColumnSpec,
+    scenario,
+  );
+  if (err) return [scenario, err];
+  return [
+    {
+      ...scenario,
+      Buses: {
+        ...scenario.Buses,
+        [bus]: newBus,
+      } as Buses,
+    },
+    null,
+  ];
+};
+
+export const deleteBus = (bus: string, scenario: UnitCommitmentScenario) => {
+  const { [bus]: _, ...newBuses } = scenario.Buses;
+  const newGenerators = { ...scenario.Generators };
+
+  // Update generators
+  for (const genName in scenario.Generators) {
+    let gen = scenario.Generators[genName]!;
+    if (gen["Bus"] === bus) delete newGenerators[genName];
+  }
+  return { ...scenario, Buses: newBuses, Generators: newGenerators };
+};
+
+export const renameBus = (
+  oldName: string,
+  newName: string,
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const [newBuses, err] = renameItemInObject(oldName, newName, scenario.Buses);
+  if (err) return [scenario, err];
+
+  // Update generators
+  const newGenerators = { ...scenario.Generators };
+  for (const genName in scenario.Generators) {
+    let gen = newGenerators[genName]!;
+    if (gen["Bus"] === oldName) {
+      newGenerators[genName] = { ...gen, Bus: newName };
+    }
+  }
+  return [{ ...scenario, Buses: newBuses, Generators: newGenerators }, null];
+};

web/frontend/src/core/Operations/commonOps.test.ts

@@ -0,0 +1,30 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { parseBool } from "./commonOps";
+import assert from "node:assert";
+
+test("parseBool", () => {
+  // True values
+  for (const str of ["true", "TRUE", "1"]) {
+    let [v, err] = parseBool(str);
+    assert(!err);
+    assert.equal(v, true);
+  }
+
+  // False values
+  for (const str of ["false", "FALSE", "0"]) {
+    let [v, err] = parseBool(str);
+    assert(!err);
+    assert.equal(v, false);
+  }
+
+  // Invalid values
+  for (const str of ["qwe", ""]) {
+    let [, err] = parseBool(str);
+    assert(err);
+  }
+});

web/frontend/src/core/Operations/commonOps.ts

@@ -0,0 +1,258 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { ValidationError } from "../Data/validate";
+import { ColumnSpec } from "../../components/Common/Forms/DataTable";
+import { UnitCommitmentScenario } from "../Data/types";
+
+export const renameItemInObject = <T>(
+  oldName: string,
+  newName: string,
+  container: { [key: string]: T },
+): [{ [key: string]: T }, ValidationError | null] => {
+  if (newName in container) {
+    return [container, { message: `${newName} already exists` }];
+  }
+  const newContainer = Object.keys(container).reduce(
+    (acc, val) => {
+      if (val === oldName) {
+        acc[newName] = container[val]!;
+      } else {
+        acc[val] = container[val]!;
+      }
+      return acc;
+    },
+    {} as { [key: string]: T },
+  );
+  return [newContainer, null];
+};
+
+export const generateUniqueName = (container: any, prefix: string): string => {
+  let counter = 1;
+  let name = `${prefix}${counter}`;
+  while (name in container) {
+    counter++;
+    name = `${prefix}${counter}`;
+  }
+  return name;
+};
+
+export const parseNumber = (
+  valueStr: string,
+): [number, ValidationError | null] => {
+  if (valueStr === "") {
+    return [0, { message: "Field must not be blank" }];
+  }
+  const valueFloat = parseFloat(valueStr);
+  if (isNaN(valueFloat)) {
+    return [0, { message: `"${valueStr}" is not a valid number` }];
+  } else {
+    return [valueFloat, null];
+  }
+};
+
+export const parseNullableNumber = (
+  valueStr: string,
+): [number | null, ValidationError | null] => {
+  if (valueStr === "") return [null, null];
+  return parseNumber(valueStr);
+};
+
+export const parseBool = (
+  valueStr: string,
+): [boolean, ValidationError | null] => {
+  if (["true", "1"].includes(valueStr.toLowerCase())) {
+    return [true, null];
+  }
+  if (["false", "0"].includes(valueStr.toLowerCase())) {
+    return [false, null];
+  }
+  return [true, { message: `"${valueStr}" is not a valid boolean value` }];
+};
+
+export const changeStringData = (
+  field: string,
+  newValue: string,
+  container: { [key: string]: any },
+): [{ [key: string]: any }, ValidationError | null] => {
+  return [
+    {
+      ...container,
+      [field]: newValue,
+    },
+    null,
+  ];
+};
+
+export const changeBusRefData = (
+  field: string,
+  newValue: string,
+  container: { [key: string]: any },
+  scenario: UnitCommitmentScenario,
+): [{ [key: string]: any }, ValidationError | null] => {
+  if (!(newValue in scenario.Buses)) {
+    return [scenario, { message: `Bus "${newValue}" does not exist` }];
+  }
+  return changeStringData(field, newValue, container);
+};
+
+export const changeNumberData = (
+  field: string,
+  newValueStr: string,
+  container: { [key: string]: any },
+  nullable: boolean = false,
+): [{ [key: string]: any }, ValidationError | null] => {
+  // Parse value
+  const [newValueFloat, err] = nullable
+    ? parseNullableNumber(newValueStr)
+    : parseNumber(newValueStr);
+  if (err) return [container, err];
+
+  // Build the new object
+  return [
+    {
+      ...container,
+      [field]: newValueFloat,
+    },
+    null,
+  ];
+};
+
+export const changeBooleanData = (
+  field: string,
+  newValueStr: string,
+  container: { [key: string]: any },
+): [{ [key: string]: any }, ValidationError | null] => {
+  // Parse value
+  const [newValueBool, err] = parseBool(newValueStr);
+  if (err) return [container, err];
+
+  // Build the new object
+  return [
+    {
+      ...container,
+      [field]: newValueBool,
+    },
+    null,
+  ];
+};
+
+export const changeNumberVecTData = (
+  field: string,
+  time: string,
+  newValueStr: string,
+  container: { [key: string]: any },
+  scenario: UnitCommitmentScenario,
+): [{ [key: string]: any }, ValidationError | null] => {
+  // Parse value
+  const [newValueFloat, err] = parseNumber(newValueStr);
+  if (err) return [container, err];
+
+  // Convert HH:MM to offset
+  const hours = parseInt(time.split(":")[0]!, 10);
+  const min = parseInt(time.split(":")[1]!, 10);
+  const idx = (hours * 60 + min) / scenario.Parameters["Time step (min)"];
+
+  // Build the new vector
+  const newVec = [...container[field]];
+  newVec[idx] = newValueFloat;
+  return [
+    {
+      ...container,
+      [field]: newVec,
+    },
+    null,
+  ];
+};
+
+export const changeNumberVecNData = (
+  field: string,
+  offset: string,
+  newValueStr: string,
+  container: { [key: string]: any },
+): [{ [key: string]: any }, ValidationError | null] => {
+  const oldVec = container[field];
+  const newVec = [...container[field]];
+  const idx = parseInt(offset) - 1;
+
+  if (newValueStr === "") {
+    // Trim the vector
+    newVec.splice(idx, oldVec.length - idx);
+  } else {
+    // Parse new value
+    const [newValueFloat, err] = parseNumber(newValueStr);
+    if (err) return [container, err];
+
+    // Increase the length of the vector
+    if (idx >= oldVec.length) {
+      for (let i = oldVec.length; i < idx; i++) {
+        newVec[i] = 0;
+      }
+    }
+
+    // Assign new value
+    newVec[idx] = newValueFloat;
+  }
+  return [
+    {
+      ...container,
+      [field]: newVec,
+    },
+    null,
+  ];
+};
+
+export const changeData = (
+  field: string,
+  newValueStr: string,
+  container: { [key: string]: any },
+  colSpecs: ColumnSpec[],
+  scenario: UnitCommitmentScenario,
+): [{ [key: string]: any }, ValidationError | null] => {
+  const match = field.match(/^([^0-9]+)([0-9:]+)?$/);
+  const fieldName = match![1]!.trim();
+  const fieldOffset = match![2];
+  for (const spec of colSpecs) {
+    if (spec.title !== fieldName) continue;
+    switch (spec.type) {
+      case "string":
+        return changeStringData(fieldName, newValueStr, container);
+      case "busRef":
+        return changeBusRefData(fieldName, newValueStr, container, scenario);
+      case "number":
+        return changeNumberData(fieldName, newValueStr, container);
+      case "number?":
+        return changeNumberData(fieldName, newValueStr, container, true);
+      case "number[T]":
+        return changeNumberVecTData(
+          fieldName,
+          fieldOffset!,
+          newValueStr,
+          container,
+          scenario,
+        );
+      case "number[N]":
+        return changeNumberVecNData(
+          fieldName,
+          fieldOffset!,
+          newValueStr,
+          container,
+        );
+      case "boolean":
+        return changeBooleanData(fieldName, newValueStr, container);
+      default:
+        throw Error(`Unknown type: ${spec.type}`);
+    }
+  }
+  throw Error(`Unknown field: ${fieldName}`);
+};
+export const assertBusesNotEmpty = (
+  scenario: UnitCommitmentScenario,
+): ValidationError | null => {
+  if (Object.keys(scenario.Buses).length === 0)
+    return { message: "This component requires an existing bus." };
+  return null;
+};

web/frontend/src/core/Operations/generatorOps.test.ts

@@ -0,0 +1,151 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { TEST_DATA_1, TEST_DATA_BLANK } from "../Data/fixtures.test";
+import assert from "node:assert";
+import {
+  changeProfiledUnitData,
+  changeThermalUnitData,
+  createProfiledUnit,
+  createThermalUnit,
+  deleteGenerator,
+  renameGenerator,
+} from "./generatorOps";
+import { ValidationError } from "../Data/validate";
+
+test("createProfiledUnit", () => {
+  const [newScenario, err] = createProfiledUnit(TEST_DATA_1);
+  assert(err === null);
+  assert.equal(Object.keys(newScenario.Generators).length, 4);
+  assert("pu3" in newScenario.Generators);
+});
+
+test("createThermalUnit", () => {
+  const [newScenario, err] = createThermalUnit(TEST_DATA_1);
+  assert(err === null);
+  assert.equal(Object.keys(newScenario.Generators).length, 4);
+  assert("g2" in newScenario.Generators);
+});
+
+test("createProfiledUnit with blank file", () => {
+  const [, err] = createProfiledUnit(TEST_DATA_BLANK);
+  assert(err !== null);
+  assert.equal(err.message, "This component requires an existing bus.");
+});
+
+test("changeProfiledUnitData", () => {
+  let scenario = TEST_DATA_1;
+  let err: ValidationError | null;
+  [scenario, err] = changeProfiledUnitData(
+    "pu1",
+    "Cost ($/MW)",
+    "99",
+    scenario,
+  );
+  assert.equal(err, null);
+  [scenario, err] = changeProfiledUnitData(
+    "pu1",
+    "Maximum power (MW) 03:00",
+    "99",
+    scenario,
+  );
+  assert.equal(err, null);
+  [scenario, err] = changeProfiledUnitData("pu2", "Bus", "b3", scenario);
+  assert.equal(err, null);
+  assert.deepEqual(scenario.Generators["pu2"], {
+    Bus: "b3",
+    Type: "Profiled",
+    "Cost ($/MW)": 120,
+    "Maximum power (MW)": [50, 50, 50, 50, 50],
+    "Minimum power (MW)": [0, 0, 0, 0, 0],
+  });
+});
+
+test("changeThermalUnitData", () => {
+  let scenario = TEST_DATA_1;
+  let err: ValidationError | null;
+  [scenario, err] = changeThermalUnitData(
+    "g1",
+    "Ramp up limit (MW)",
+    "99",
+    scenario,
+  );
+  assert(!err);
+  [scenario, err] = changeThermalUnitData(
+    "g1",
+    "Startup costs ($) 2",
+    "99",
+    scenario,
+  );
+  assert(!err);
+  [scenario, err] = changeThermalUnitData(
+    "g1",
+    "Production cost curve ($) 7",
+    "99",
+    scenario,
+  );
+  assert(!err);
+  [scenario, err] = changeThermalUnitData(
+    "g1",
+    "Production cost curve (MW) 3",
+    "",
+    scenario,
+  );
+  assert(!err);
+  [scenario, err] = changeThermalUnitData("g1", "Must run?", "true", scenario);
+  assert(!err);
+  assert.deepEqual(scenario.Generators["g1"], {
+    Bus: "b1",
+    Type: "Thermal",
+    "Production cost curve (MW)": [100.0, 110],
+    "Production cost curve ($)": [1400.0, 1600.0, 2200.0, 2400.0, 0, 0, 99],
+    "Startup costs ($)": [300.0, 99.0],
+    "Startup delays (h)": [1, 4],
+    "Ramp up limit (MW)": 99,
+    "Ramp down limit (MW)": 232.68,
+    "Startup limit (MW)": 232.68,
+    "Shutdown limit (MW)": 232.68,
+    "Minimum downtime (h)": 4,
+    "Minimum uptime (h)": 4,
+    "Initial status (h)": 12,
+    "Initial power (MW)": 115,
+    "Must run?": true,
+  });
+});
+
+test("changeProfiledUnitData with invalid bus", () => {
+  let scenario = TEST_DATA_1;
+  let err = null;
+  [scenario, err] = changeProfiledUnitData("pu1", "Bus", "b99", scenario);
+  assert(err !== null);
+  assert.equal(err.message, 'Bus "b99" does not exist');
+});
+
+test("deleteGenerator", () => {
+  const newScenario = deleteGenerator("pu1", TEST_DATA_1);
+  assert.equal(Object.keys(newScenario.Generators).length, 2);
+  assert("g1" in newScenario.Generators);
+  assert("pu2" in newScenario.Generators);
+});
+
+test("renameGenerator", () => {
+  const [newScenario, err] = renameGenerator("pu1", "pu5", TEST_DATA_1);
+  assert(err === null);
+  assert.deepEqual(newScenario.Generators["pu5"], {
+    Bus: "b1",
+    Type: "Profiled",
+    "Cost ($/MW)": 12.5,
+    "Maximum power (MW)": [10, 12, 13, 15, 20],
+    "Minimum power (MW)": [0, 0, 0, 0, 0],
+  });
+  assert.deepEqual(newScenario.Generators["pu2"], {
+    Bus: "b1",
+    Type: "Profiled",
+    "Cost ($/MW)": 120,
+    "Maximum power (MW)": [50, 50, 50, 50, 50],
+    "Minimum power (MW)": [0, 0, 0, 0, 0],
+  });
+});

web/frontend/src/core/Operations/generatorOps.ts

@@ -0,0 +1,152 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { generateTimeslots } from "../../components/Common/Forms/DataTable";
+import { ValidationError } from "../Data/validate";
+import {
+  assertBusesNotEmpty,
+  changeData,
+  generateUniqueName,
+  renameItemInObject,
+} from "./commonOps";
+import { ProfiledUnitsColumnSpec } from "../../components/CaseBuilder/ProfiledUnits";
+import { ThermalUnitsColumnSpec } from "../../components/CaseBuilder/ThermalUnits";
+import { Generators, UnitCommitmentScenario } from "../Data/types";
+
+export const createProfiledUnit = (
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const err = assertBusesNotEmpty(scenario);
+  if (err) return [scenario, err];
+  const busName = Object.keys(scenario.Buses)[0]!;
+  const timeslots = generateTimeslots(scenario);
+  const name = generateUniqueName(scenario.Generators, "pu");
+  return [
+    {
+      ...scenario,
+      Generators: {
+        ...scenario.Generators,
+        [name]: {
+          Bus: busName,
+          Type: "Profiled",
+          "Cost ($/MW)": 0,
+          "Minimum power (MW)": Array(timeslots.length).fill(0),
+          "Maximum power (MW)": Array(timeslots.length).fill(0),
+        },
+      },
+    },
+    null,
+  ];
+};
+
+export const createThermalUnit = (
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const err = assertBusesNotEmpty(scenario);
+  if (err) return [scenario, err];
+  const busName = Object.keys(scenario.Buses)[0]!;
+  const name = generateUniqueName(scenario.Generators, "g");
+  return [
+    {
+      ...scenario,
+      Generators: {
+        ...scenario.Generators,
+        [name]: {
+          Bus: busName,
+          Type: "Thermal",
+          "Production cost curve (MW)": [0, 100],
+          "Production cost curve ($)": [0, 10],
+          "Startup costs ($)": [0],
+          "Startup delays (h)": [1],
+          "Ramp up limit (MW)": null,
+          "Ramp down limit (MW)": null,
+          "Startup limit (MW)": null,
+          "Shutdown limit (MW)": null,
+          "Minimum downtime (h)": 1,
+          "Minimum uptime (h)": 1,
+          "Initial status (h)": -24,
+          "Initial power (MW)": 0,
+          "Must run?": false,
+        },
+      },
+    },
+    null,
+  ];
+};
+
+export const changeProfiledUnitData = (
+  generator: string,
+  field: string,
+  newValueStr: string,
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const [newGen, err] = changeData(
+    field,
+    newValueStr,
+    scenario.Generators[generator]!,
+    ProfiledUnitsColumnSpec,
+    scenario,
+  );
+  if (err) return [scenario, err];
+  return [
+    {
+      ...scenario,
+      Generators: {
+        ...scenario.Generators,
+        [generator]: newGen,
+      } as Generators,
+    },
+    null,
+  ];
+};
+
+export const changeThermalUnitData = (
+  generator: string,
+  field: string,
+  newValueStr: string,
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const [newGen, err] = changeData(
+    field,
+    newValueStr,
+    scenario.Generators[generator]!,
+    ThermalUnitsColumnSpec,
+    scenario,
+  );
+  if (err) return [scenario, err];
+  return [
+    {
+      ...scenario,
+      Generators: {
+        ...scenario.Generators,
+        [generator]: newGen,
+      } as Generators,
+    },
+    null,
+  ];
+};
+
+export const deleteGenerator = (
+  name: string,
+  scenario: UnitCommitmentScenario,
+): UnitCommitmentScenario => {
+  const { [name]: _, ...newGenerators } = scenario.Generators;
+  return { ...scenario, Generators: newGenerators };
+};
+
+export const renameGenerator = (
+  oldName: string,
+  newName: string,
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const [newGen, err] = renameItemInObject(
+    oldName,
+    newName,
+    scenario.Generators,
+  );
+  if (err) return [scenario, err];
+  return [{ ...scenario, Generators: newGen }, null];
+};

web/frontend/src/core/Operations/parameterOps.test.ts

@@ -0,0 +1,137 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import {
+  changeTimeHorizon,
+  changeTimeStep,
+  evaluatePwlFunction,
+} from "./parameterOps";
+import assert from "node:assert";
+import { TEST_DATA_1, TEST_DATA_2 } from "../Data/fixtures.test";
+
+test("changeTimeHorizon: Shrink 1", () => {
+  const [newScenario, err] = changeTimeHorizon(TEST_DATA_1, "3");
+  assert(err === null);
+  assert.deepEqual(newScenario.Parameters, {
+    Version: "0.4",
+    "Power balance penalty ($/MW)": 1000.0,
+    "Time horizon (h)": 3,
+    "Time step (min)": 60,
+  });
+  assert.deepEqual(newScenario.Buses, {
+    b1: { "Load (MW)": [35.79534, 34.38835, 33.45083] },
+    b2: { "Load (MW)": [14.03739, 13.48563, 13.11797] },
+    b3: { "Load (MW)": [27.3729, 26.29698, 25.58005] },
+  });
+});
+
+test("changeTimeHorizon: Shrink 2", () => {
+  const [newScenario, err] = changeTimeHorizon(TEST_DATA_2, "1");
+  assert(err === null);
+  assert.deepEqual(newScenario.Parameters, {
+    Version: "0.4",
+    "Power balance penalty ($/MW)": 1000.0,
+    "Time horizon (h)": 1,
+    "Time step (min)": 30,
+  });
+  assert.deepEqual(newScenario.Buses, {
+    b1: { "Load (MW)": [30, 30] },
+    b2: { "Load (MW)": [10, 20] },
+    b3: { "Load (MW)": [0, 30] },
+  });
+});
+
+test("changeTimeHorizon grow", () => {
+  const [newScenario, err] = changeTimeHorizon(TEST_DATA_1, "7");
+  assert(err === null);
+  assert.deepEqual(newScenario.Parameters, {
+    Version: "0.4",
+    "Power balance penalty ($/MW)": 1000.0,
+    "Time horizon (h)": 7,
+    "Time step (min)": 60,
+  });
+  assert.deepEqual(newScenario.Buses, {
+    b1: {
+      "Load (MW)": [35.79534, 34.38835, 33.45083, 32.89729, 33.25044, 0, 0],
+    },
+    b2: {
+      "Load (MW)": [14.03739, 13.48563, 13.11797, 12.9009, 13.03939, 0, 0],
+    },
+    b3: {
+      "Load (MW)": [27.3729, 26.29698, 25.58005, 25.15675, 25.4268, 0, 0],
+    },
+  });
+});
+
+test("changeTimeHorizon invalid", () => {
+  let [, err] = changeTimeHorizon(TEST_DATA_1, "x");
+  assert(err !== null);
+  assert.equal(err.message, "Invalid value: x");
+
+  [, err] = changeTimeHorizon(TEST_DATA_1, "-3");
+  assert(err !== null);
+  assert.equal(err.message, "Invalid value: -3");
+});
+
+test("evaluatePwlFunction", () => {
+  const data_x = [0, 60, 120, 180];
+  const data_y = [100, 200, 250, 100];
+  assert.equal(evaluatePwlFunction(data_x, data_y, 0), 100);
+  assert.equal(evaluatePwlFunction(data_x, data_y, 15), 125);
+  assert.equal(evaluatePwlFunction(data_x, data_y, 30), 150);
+  assert.equal(evaluatePwlFunction(data_x, data_y, 60), 200);
+  assert.equal(evaluatePwlFunction(data_x, data_y, 180), 100);
+});
+
+test("changeTimeStep", () => {
+  let [scenario, err] = changeTimeStep(TEST_DATA_2, "15");
+  assert(err === null);
+  assert.deepEqual(scenario.Parameters, {
+    Version: "0.4",
+    "Power balance penalty ($/MW)": 1000.0,
+    "Time horizon (h)": 2,
+    "Time step (min)": 15,
+  });
+  assert.deepEqual(scenario.Buses, {
+    b1: { "Load (MW)": [30, 30, 30, 30, 30, 30, 30, 30] },
+    b2: { "Load (MW)": [10, 15, 20, 25, 30, 35, 40, 25] },
+    b3: { "Load (MW)": [0, 15, 30, 15, 0, 20, 40, 20] },
+  });
+
+  [scenario, err] = changeTimeStep(TEST_DATA_2, "60");
+  assert(err === null);
+  assert.deepEqual(scenario.Parameters, {
+    Version: "0.4",
+    "Power balance penalty ($/MW)": 1000.0,
+    "Time horizon (h)": 2,
+    "Time step (min)": 60,
+  });
+  assert.deepEqual(scenario.Buses, {
+    b1: { "Load (MW)": [30, 30] },
+    b2: { "Load (MW)": [10, 30] },
+    b3: { "Load (MW)": [0, 0] },
+  });
+});
+
+test("changeTimeStep invalid", () => {
+  let [, err] = changeTimeStep(TEST_DATA_2, "x");
+  assert(err !== null);
+  assert.equal(err.message, "Invalid value: x");
+
+  [, err] = changeTimeStep(TEST_DATA_2, "-10");
+  assert(err !== null);
+  assert.equal(err.message, "Invalid value: -10");
+
+  [, err] = changeTimeStep(TEST_DATA_2, "120");
+  assert(err !== null);
+  assert.equal(err.message, "Invalid value: 120");
+
+  [, err] = changeTimeStep(TEST_DATA_2, "7");
+  assert(err !== null);
+  assert.equal(err.message, "Time step must be a divisor of 60: 7");
+});
+
+export {};

web/frontend/src/core/Operations/parameterOps.ts

@@ -0,0 +1,221 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { Buses } from "../Data/fixtures";
+import { ValidationError } from "../Data/validate";
+import { UnitCommitmentScenario } from "../Data/types";
+
+export const changeTimeHorizon = (
+  scenario: UnitCommitmentScenario,
+  newTimeHorizonStr: string,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  // Parse string
+  const newTimeHorizon = parseInt(newTimeHorizonStr);
+  if (isNaN(newTimeHorizon) || newTimeHorizon <= 0) {
+    return [scenario, { message: `Invalid value: ${newTimeHorizonStr}` }];
+  }
+  const newScenario = JSON.parse(
+    JSON.stringify(scenario),
+  ) as UnitCommitmentScenario;
+  newScenario.Parameters["Time horizon (h)"] = newTimeHorizon;
+  const newT = (newTimeHorizon * 60) / scenario.Parameters["Time step (min)"];
+  const oldT =
+    (scenario.Parameters["Time horizon (h)"] * 60) /
+    scenario.Parameters["Time step (min)"];
+  if (newT < oldT) {
+    Object.values(newScenario.Buses).forEach((bus) => {
+      bus["Load (MW)"] = bus["Load (MW)"].slice(0, newT);
+    });
+    Object.values(newScenario.Generators).forEach((generator) => {
+      if (generator.Type === "Profiled") {
+        generator["Minimum power (MW)"] = generator["Minimum power (MW)"].slice(0, newT);
+        generator["Maximum power (MW)"] = generator["Maximum power (MW)"].slice(0, newT);
+      }
+    });
+    Object.values(newScenario["Price-sensitive loads"]).forEach((psLoad) => {
+      psLoad["Demand (MW)"] = psLoad["Demand (MW)"].slice(0, newT);
+    });
+  } else {
+    const padding = Array(newT - oldT).fill(0);
+    Object.values(newScenario.Buses).forEach((bus) => {
+      bus["Load (MW)"] = bus["Load (MW)"].concat(padding);
+    });
+    Object.values(newScenario.Generators).forEach((generator) => {
+      if (generator.Type === "Profiled") {
+        generator["Minimum power (MW)"] = generator["Minimum power (MW)"].concat(padding);
+        generator["Maximum power (MW)"] = generator["Maximum power (MW)"].concat(padding);
+      }
+    });
+    Object.values(newScenario["Price-sensitive loads"]).forEach((psLoad) => {
+      psLoad["Demand (MW)"] = psLoad["Demand (MW)"].concat(padding);
+    });
+  }
+  return [newScenario, null];
+};
+
+export const evaluatePwlFunction = (
+  data_x: number[],
+  data_y: number[],
+  x: number,
+) => {
+  if (x < data_x[0]! || x > data_x[data_x.length - 1]!) {
+    throw Error("PWL interpolation: Out of bounds");
+  }
+
+  if (x === data_x[0]) return data_y[0];
+
+  // Binary search to find the interval containing x
+  let low = 0;
+  let high = data_x.length - 1;
+  while (low < high) {
+    let mid = Math.floor((low + high) / 2);
+    if (data_x[mid]! < x) low = mid + 1;
+    else high = mid;
+  }
+
+  // Linear interpolation within the found interval
+  const x1 = data_x[low - 1]!;
+  const y1 = data_y[low - 1]!;
+  const x2 = data_x[low]!;
+  const y2 = data_y[low]!;
+
+  return y1 + ((x - x1) * (y2 - y1)) / (x2 - x1);
+};
+
+export const changeTimeStep = (
+  scenario: UnitCommitmentScenario,
+  newTimeStepStr: string,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  // Parse string and perform validation
+  const newTimeStep = parseFloat(newTimeStepStr);
+  if (isNaN(newTimeStep) || newTimeStep < 1 || newTimeStep > 60) {
+    return [scenario, { message: `Invalid value: ${newTimeStepStr}` }];
+  }
+  if (60 % newTimeStep !== 0) {
+    return [
+      scenario,
+      { message: `Time step must be a divisor of 60: ${newTimeStepStr}` },
+    ];
+  }
+
+  // Build data_x
+  let timeHorizon = scenario.Parameters["Time horizon (h)"];
+  const oldTimeStep = scenario.Parameters["Time step (min)"];
+  const oldT = (timeHorizon * 60) / oldTimeStep;
+  const newT = (timeHorizon * 60) / newTimeStep;
+  const data_x = Array(oldT + 1).fill(0);
+  for (let i = 0; i <= oldT; i++) data_x[i] = i * oldTimeStep;
+
+  const newBuses: Buses = {};
+  for (const busName in scenario.Buses) {
+    // Build data_y
+    const busLoad = scenario.Buses[busName]!["Load (MW)"];
+    const data_y = Array(oldT + 1).fill(0);
+    for (let i = 0; i < oldT; i++) data_y[i] = busLoad[i];
+    data_y[oldT] = data_y[0];
+
+    // Run interpolation
+    const newBusLoad = Array(newT).fill(0);
+    for (let i = 0; i < newT; i++) {
+      newBusLoad[i] = evaluatePwlFunction(data_x, data_y, newTimeStep * i);
+    }
+    newBuses[busName] = {
+      ...scenario.Buses[busName],
+      "Load (MW)": newBusLoad,
+    };
+  }
+
+  const newGenerators: { [name: string]: any } = {};
+  for (const generatorName in scenario.Generators) {
+    const generator = scenario.Generators[generatorName]!;
+    if (generator.Type === "Profiled") {
+      // Build data_y for minimum power
+      const minPower = generator["Minimum power (MW)"];
+      const minData_y = Array(oldT + 1).fill(0);
+      for (let i = 0; i < oldT; i++) minData_y[i] = minPower[i];
+      minData_y[oldT] = minData_y[0];
+
+      // Build data_y for maximum power
+      const maxPower = generator["Maximum power (MW)"];
+      const maxData_y = Array(oldT + 1).fill(0);
+      for (let i = 0; i < oldT; i++) maxData_y[i] = maxPower[i];
+      maxData_y[oldT] = maxData_y[0];
+
+      // Run interpolation for both
+      const newMinPower = Array(newT).fill(0);
+      const newMaxPower = Array(newT).fill(0);
+      for (let i = 0; i < newT; i++) {
+        newMinPower[i] = evaluatePwlFunction(data_x, minData_y, newTimeStep * i);
+        newMaxPower[i] = evaluatePwlFunction(data_x, maxData_y, newTimeStep * i);
+      }
+
+      newGenerators[generatorName] = {
+        ...generator,
+        "Minimum power (MW)": newMinPower,
+        "Maximum power (MW)": newMaxPower,
+      };
+    } else {
+      newGenerators[generatorName] = generator;
+    }
+  }
+
+  const newPriceSensitiveLoads: { [name: string]: any } = {};
+  for (const psLoadName in scenario["Price-sensitive loads"]) {
+    const psLoad = scenario["Price-sensitive loads"][psLoadName]!;
+    
+    // Build data_y for demand
+    const demand = psLoad["Demand (MW)"];
+    const demandData_y = Array(oldT + 1).fill(0);
+    for (let i = 0; i < oldT; i++) demandData_y[i] = demand[i];
+    demandData_y[oldT] = demandData_y[0];
+
+    // Run interpolation for demand
+    const newDemand = Array(newT).fill(0);
+    for (let i = 0; i < newT; i++) {
+      newDemand[i] = evaluatePwlFunction(data_x, demandData_y, newTimeStep * i);
+    }
+
+    newPriceSensitiveLoads[psLoadName] = {
+      ...psLoad,
+      "Demand (MW)": newDemand,
+    };
+  }
+
+  return [
+    {
+      ...scenario,
+      Parameters: {
+        ...scenario.Parameters,
+        "Time step (min)": newTimeStep,
+      },
+      Buses: newBuses,
+      Generators: newGenerators,
+      "Price-sensitive loads": newPriceSensitiveLoads,
+    },
+    null,
+  ];
+};
+
+export const changeParameter = (
+  scenario: UnitCommitmentScenario,
+  key: string,
+  valueStr: string,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const value = parseFloat(valueStr);
+  if (isNaN(value)) {
+    return [scenario, { message: `Invalid value: ${valueStr}` }];
+  }
+  return [
+    {
+      ...scenario,
+      Parameters: {
+        ...scenario.Parameters,
+        [key]: value,
+      },
+    },
+    null,
+  ];
+};

web/frontend/src/core/Operations/preprocessing.test.ts

@@ -0,0 +1,46 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import assert from "node:assert";
+import { preprocess } from "./preprocessing";
+
+export const PREPROCESSING_TEST_DATA_1: any = {
+  Parameters: {
+    Version: "0.4",
+    "Time horizon (h)": 5,
+  },
+  Buses: {
+    b1: { "Load (MW)": [35.79534, 34.38835, 33.45083, 32.89729, 33.25044] },
+    b2: { "Load (MW)": 10 },
+    b3: { "Load (MW)": [27.3729, 26.29698, 25.58005, 25.15675, 25.4268] },
+  },
+};
+
+test("preprocess", () => {
+  const [newScenario, err] = preprocess(PREPROCESSING_TEST_DATA_1);
+  assert(err === null);
+  assert.deepEqual(newScenario, {
+    Parameters: {
+      Version: "0.4",
+      "Time horizon (h)": 5,
+      "Power balance penalty ($/MW)": 1000,
+      "Scenario name": "s1",
+      "Scenario weight": 1,
+      "Time step (min)": 60,
+    },
+    Buses: {
+      b1: { "Load (MW)": [35.79534, 34.38835, 33.45083, 32.89729, 33.25044] },
+      b2: { "Load (MW)": [10, 10, 10, 10, 10] },
+      b3: { "Load (MW)": [27.3729, 26.29698, 25.58005, 25.15675, 25.4268] },
+    },
+    "Price-sensitive loads": {},
+    "Storage units": {},
+    "Transmission lines": {},
+    Contingencies: {},
+    Generators: {},
+    Reserves: {},
+  });
+});

web/frontend/src/core/Operations/preprocessing.ts

@@ -0,0 +1,70 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { validate, ValidationError } from "../Data/validate";
+import { UnitCommitmentScenario } from "../Data/types";
+import { migrate } from "../Data/migrate";
+import {
+  getContingencyTransmissionLines,
+  rebuildContingencies,
+} from "./transmissionOps";
+
+export const preprocess = (
+  data: any,
+): [UnitCommitmentScenario | null, ValidationError | null] => {
+  // Make a copy of the original data
+  let result = JSON.parse(JSON.stringify(data));
+
+  // Run migration
+  migrate(result);
+
+  // Run JSON validation and assign default values
+  if (!validate(result)) {
+    console.error(validate.errors);
+    return [
+      null,
+      { message: "Invalid JSON file. See console for more details." },
+    ];
+  }
+
+  // Expand scalars into arrays
+  // @ts-ignore
+  const timeHorizon = result["Parameters"]["Time horizon (h)"];
+  // @ts-ignore
+  const timeStep = result["Parameters"]["Time step (min)"];
+  const T = (timeHorizon * 60) / timeStep;
+  for (const busName in result["Buses"]) {
+    // @ts-ignore
+    const busData = result["Buses"][busName];
+    const busLoad = busData["Load (MW)"];
+    if (typeof busLoad === "number") {
+      busData["Load (MW)"] = Array(T).fill(busLoad);
+    }
+  }
+
+  // Add optional fields
+  for (let field of [
+    "Buses",
+    "Generators",
+    "Storage units",
+    "Price-sensitive loads",
+    "Transmission lines",
+    "Reserves",
+    "Contingencies",
+  ]) {
+    if (!result[field]) {
+      result[field] = {};
+    }
+  }
+
+  const scenario = result as unknown as UnitCommitmentScenario;
+
+  // Rebuild contingencies
+  const contingencyLines = getContingencyTransmissionLines(scenario);
+  scenario["Contingencies"] = rebuildContingencies(contingencyLines);
+
+  return [scenario, null];
+};

web/frontend/src/core/Operations/psloadOps.test.ts

@@ -0,0 +1,60 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { TEST_DATA_1 } from "../Data/fixtures.test";
+import assert from "node:assert";
+import {
+  changePriceSensitiveLoadData,
+  createPriceSensitiveLoad,
+  deletePriceSensitiveLoad,
+  renamePriceSensitiveLoad,
+} from "./psloadOps";
+import { ValidationError } from "../Data/validate";
+
+test("createPriceSensitiveLoad", () => {
+  const [newScenario, err] = createPriceSensitiveLoad(TEST_DATA_1);
+  assert(err === null);
+  assert.equal(Object.keys(newScenario["Price-sensitive loads"]).length, 2);
+  assert("ps2" in newScenario["Price-sensitive loads"]);
+});
+
+test("renamePriceSensitiveLoad", () => {
+  const [newScenario, err] = renamePriceSensitiveLoad(
+    "ps1",
+    "ps2",
+    TEST_DATA_1,
+  );
+  assert(err === null);
+  assert.deepEqual(
+    newScenario["Price-sensitive loads"]["ps2"],
+    TEST_DATA_1["Price-sensitive loads"]["ps1"],
+  );
+  assert.equal(Object.keys(newScenario["Price-sensitive loads"]).length, 1);
+});
+
+test("changePriceSensitiveLoadData", () => {
+  let scenario = TEST_DATA_1;
+  let err: ValidationError | null;
+  [scenario, err] = changePriceSensitiveLoadData("ps1", "Bus", "b3", scenario);
+  assert.equal(err, null);
+  [scenario, err] = changePriceSensitiveLoadData(
+    "ps1",
+    "Demand (MW) 00:00",
+    "99",
+    scenario,
+  );
+  assert.equal(err, null);
+  assert.deepEqual(scenario["Price-sensitive loads"]["ps1"], {
+    Bus: "b3",
+    "Revenue ($/MW)": 23,
+    "Demand (MW)": [99, 50, 50, 50, 50],
+  });
+});
+
+test("deletePriceSensitiveLoad", () => {
+  const newScenario = deletePriceSensitiveLoad("ps1", TEST_DATA_1);
+  assert.equal(Object.keys(newScenario["Price-sensitive loads"]).length, 0);
+});

web/frontend/src/core/Operations/psloadOps.ts

@@ -0,0 +1,88 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { ValidationError } from "../Data/validate";
+import { PriceSensitiveLoad, UnitCommitmentScenario } from "../Data/types";
+import {
+  assertBusesNotEmpty,
+  changeData,
+  generateUniqueName,
+  renameItemInObject,
+} from "./commonOps";
+import { PriceSensitiveLoadsColumnSpec } from "../../components/CaseBuilder/Psload";
+import { generateTimeslots } from "../../components/Common/Forms/DataTable";
+
+export const createPriceSensitiveLoad = (
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const err = assertBusesNotEmpty(scenario);
+  if (err) return [scenario, err];
+  const busName = Object.keys(scenario.Buses)[0]!;
+  const timeslots = generateTimeslots(scenario);
+  const name = generateUniqueName(scenario["Price-sensitive loads"], "ps");
+  return [
+    {
+      ...scenario,
+      "Price-sensitive loads": {
+        ...scenario["Price-sensitive loads"],
+        [name]: {
+          Bus: busName,
+          "Revenue ($/MW)": 0,
+          "Demand (MW)": Array(timeslots.length).fill(0),
+        },
+      },
+    },
+    null,
+  ];
+};
+
+export const renamePriceSensitiveLoad = (
+  oldName: string,
+  newName: string,
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const [newObj, err] = renameItemInObject(
+    oldName,
+    newName,
+    scenario["Price-sensitive loads"],
+  );
+  if (err) return [scenario, err];
+  return [{ ...scenario, "Price-sensitive loads": newObj }, null];
+};
+
+export const changePriceSensitiveLoadData = (
+  name: string,
+  field: string,
+  newValueStr: string,
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const [newObj, err] = changeData(
+    field,
+    newValueStr,
+    scenario["Price-sensitive loads"][name]!,
+    PriceSensitiveLoadsColumnSpec,
+    scenario,
+  );
+  if (err) return [scenario, err];
+  return [
+    {
+      ...scenario,
+      "Price-sensitive loads": {
+        ...scenario["Price-sensitive loads"],
+        [name]: newObj as PriceSensitiveLoad,
+      },
+    },
+    null,
+  ];
+};
+
+export const deletePriceSensitiveLoad = (
+  name: string,
+  scenario: UnitCommitmentScenario,
+): UnitCommitmentScenario => {
+  const { [name]: _, ...newContainer } = scenario["Price-sensitive loads"];
+  return { ...scenario, "Price-sensitive loads": newContainer };
+};

web/frontend/src/core/Operations/storageOps.test.ts

@@ -0,0 +1,75 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { TEST_DATA_1 } from "../Data/fixtures.test";
+import assert from "node:assert";
+import {
+  changeStorageUnitData,
+  createStorageUnit,
+  deleteStorageUnit,
+  renameStorageUnit,
+} from "./storageOps";
+import { ValidationError } from "../Data/validate";
+
+test("createStorageUnit", () => {
+  const [newScenario, err] = createStorageUnit(TEST_DATA_1);
+  assert(err === null);
+  assert.equal(Object.keys(newScenario["Storage units"]).length, 2);
+  assert("su2" in newScenario["Storage units"]);
+});
+
+test("renameStorageUnit", () => {
+  const [newScenario, err] = renameStorageUnit("su1", "su2", TEST_DATA_1);
+  assert(err === null);
+  assert.deepEqual(
+    newScenario["Storage units"]["su2"],
+    TEST_DATA_1["Storage units"]["su1"],
+  );
+  assert.equal(Object.keys(newScenario["Storage units"]).length, 1);
+});
+
+test("changeStorageUnitData", () => {
+  let scenario = TEST_DATA_1;
+  let err: ValidationError | null;
+  [scenario, err] = changeStorageUnitData("su1", "Bus", "b3", scenario);
+  assert.equal(err, null);
+  [scenario, err] = changeStorageUnitData(
+    "su1",
+    "Minimum level (MWh)",
+    "99",
+    scenario,
+  );
+  assert.equal(err, null);
+  [scenario, err] = changeStorageUnitData(
+    "su1",
+    "Maximum discharge rate (MW)",
+    "99",
+    scenario,
+  );
+  assert.equal(err, null);
+  assert.deepEqual(scenario["Storage units"]["su1"], {
+    Bus: "b3",
+    "Minimum level (MWh)": 99.0,
+    "Maximum level (MWh)": 100.0,
+    "Charge cost ($/MW)": 2.0,
+    "Discharge cost ($/MW)": 1.0,
+    "Charge efficiency": 0.8,
+    "Discharge efficiency": 0.85,
+    "Loss factor": 0.01,
+    "Minimum charge rate (MW)": 5.0,
+    "Maximum charge rate (MW)": 10.0,
+    "Minimum discharge rate (MW)": 4.0,
+    "Maximum discharge rate (MW)": 99.0,
+    "Initial level (MWh)": 20.0,
+    "Last period minimum level (MWh)": 21.0,
+    "Last period maximum level (MWh)": 22.0,
+  });
+});
+
+test("deleteStorageUnit", () => {
+  const newScenario = deleteStorageUnit("su1", TEST_DATA_1);
+  assert.equal(Object.keys(newScenario["Storage units"]).length, 0);
+});

web/frontend/src/core/Operations/storageOps.ts

@@ -0,0 +1,98 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { ValidationError } from "../Data/validate";
+import { StorageUnit, UnitCommitmentScenario } from "../Data/types";
+import {
+  assertBusesNotEmpty,
+  changeData,
+  generateUniqueName,
+  renameItemInObject,
+} from "./commonOps";
+import { StorageUnitsColumnSpec } from "../../components/CaseBuilder/StorageUnits";
+
+export const createStorageUnit = (
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const err = assertBusesNotEmpty(scenario);
+  if (err) return [scenario, err];
+  const busName = Object.keys(scenario.Buses)[0]!;
+  const name = generateUniqueName(scenario["Storage units"], "su");
+  return [
+    {
+      ...scenario,
+      "Storage units": {
+        ...scenario["Storage units"],
+        [name]: {
+          Bus: busName,
+          "Minimum level (MWh)": 0,
+          "Maximum level (MWh)": 1,
+          "Charge cost ($/MW)": 0.0,
+          "Discharge cost ($/MW)": 0.0,
+          "Charge efficiency": 1,
+          "Discharge efficiency": 1,
+          "Loss factor": 0,
+          "Minimum charge rate (MW)": 1,
+          "Maximum charge rate (MW)": 1,
+          "Minimum discharge rate (MW)": 1,
+          "Maximum discharge rate (MW)": 1,
+          "Initial level (MWh)": 0,
+          "Last period minimum level (MWh)": 0,
+          "Last period maximum level (MWh)": 1,
+        },
+      },
+    },
+    null,
+  ];
+};
+
+export const renameStorageUnit = (
+  oldName: string,
+  newName: string,
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const [newObj, err] = renameItemInObject(
+    oldName,
+    newName,
+    scenario["Storage units"],
+  );
+  if (err) return [scenario, err];
+  return [{ ...scenario, "Storage units": newObj }, null];
+};
+
+export const changeStorageUnitData = (
+  name: string,
+  field: string,
+  newValueStr: string,
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const [newObj, err] = changeData(
+    field,
+    newValueStr,
+    scenario["Storage units"][name]!,
+    StorageUnitsColumnSpec,
+    scenario,
+  );
+  if (err) return [scenario, err];
+  return [
+    {
+      ...scenario,
+      "Storage units": {
+        ...scenario["Storage units"],
+        [name]: newObj as StorageUnit,
+      },
+    },
+    null,
+  ];
+};
+
+export const deleteStorageUnit = (
+  name: string,
+  scenario: UnitCommitmentScenario,
+): UnitCommitmentScenario => {
+  const { [name]: _, ...newContainer } = scenario["Storage units"];
+  return { ...scenario, "Storage units": newContainer };
+};

web/frontend/src/core/Operations/transmissionOps.test.ts

@@ -0,0 +1,102 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import { TEST_DATA_1 } from "../Data/fixtures.test";
+import assert from "node:assert";
+import {
+  changeTransmissionLineData,
+  createTransmissionLine,
+  deleteTransmissionLine,
+  getContingencyTransmissionLines,
+  rebuildContingencies,
+  renameTransmissionLine,
+} from "./transmissionOps";
+import { ValidationError } from "../Data/validate";
+
+test("createTransmissionLine", () => {
+  const [newScenario, err] = createTransmissionLine(TEST_DATA_1);
+  assert(err === null);
+  assert.equal(Object.keys(newScenario["Transmission lines"]).length, 2);
+  assert("l2" in newScenario["Transmission lines"]);
+});
+
+test("renameTransmissionLine", () => {
+  const [newScenario, err] = renameTransmissionLine("l1", "l3", TEST_DATA_1);
+  assert(err === null);
+  assert.deepEqual(newScenario["Transmission lines"]["l3"], {
+    "Source bus": "b1",
+    "Target bus": "b2",
+    "Susceptance (S)": 29.49686,
+    "Normal flow limit (MW)": 15000.0,
+    "Emergency flow limit (MW)": 20000.0,
+    "Flow limit penalty ($/MW)": 5000.0,
+  });
+  assert.deepEqual(newScenario["Contingencies"], {
+    l3: {
+      "Affected lines": ["l3"],
+      "Affected generators": [],
+    },
+  });
+  assert.equal(Object.keys(newScenario["Transmission lines"]).length, 1);
+});
+
+test("changeTransmissionLineData", () => {
+  let scenario = TEST_DATA_1;
+  let err: ValidationError | null;
+  [scenario, err] = changeTransmissionLineData(
+    "l1",
+    "Source bus",
+    "b3",
+    scenario,
+  );
+  assert.equal(err, null);
+  [scenario, err] = changeTransmissionLineData(
+    "l1",
+    "Normal flow limit (MW)",
+    "99",
+    scenario,
+  );
+  assert.equal(err, null);
+  [scenario, err] = changeTransmissionLineData(
+    "l1",
+    "Target bus",
+    "b1",
+    scenario,
+  );
+  assert.equal(err, null);
+  assert.deepEqual(scenario["Transmission lines"]["l1"], {
+    "Source bus": "b3",
+    "Target bus": "b1",
+    "Susceptance (S)": 29.49686,
+    "Normal flow limit (MW)": 99,
+    "Emergency flow limit (MW)": 20000.0,
+    "Flow limit penalty ($/MW)": 5000.0,
+  });
+});
+
+test("deleteTransmissionLine", () => {
+  const newScenario = deleteTransmissionLine("l1", TEST_DATA_1);
+  assert.equal(Object.keys(newScenario["Transmission lines"]).length, 0);
+  assert.equal(Object.keys(newScenario["Contingencies"]).length, 0);
+});
+
+test("getContingencyTransmissionLines", () => {
+  const contLines = getContingencyTransmissionLines(TEST_DATA_1);
+  assert.deepEqual(contLines, new Set(["l1"]));
+});
+
+test("rebuildContingencies", () => {
+  assert.deepEqual(rebuildContingencies(new Set(["l1", "l2"])), {
+    l1: {
+      "Affected lines": ["l1"],
+      "Affected generators": [],
+    },
+    l2: {
+      "Affected lines": ["l2"],
+      "Affected generators": [],
+    },
+  });
+});

web/frontend/src/core/Operations/transmissionOps.ts

@@ -0,0 +1,163 @@
+/*
+ * UnitCommitment.jl: Optimization Package for Security-Constrained Unit Commitment
+ * Copyright (C) 2020-2025, UChicago Argonne, LLC. All rights reserved.
+ * Released under the modified BSD license. See COPYING.md for more details.
+ */
+
+import {
+  assertBusesNotEmpty,
+  changeData,
+  generateUniqueName,
+  parseBool,
+  renameItemInObject,
+} from "./commonOps";
+import { ValidationError } from "../Data/validate";
+import { TransmissionLinesColumnSpec } from "../../components/CaseBuilder/TransmissionLines";
+import {
+  Contingency,
+  TransmissionLine,
+  UnitCommitmentScenario,
+} from "../Data/types";
+
+export const createTransmissionLine = (
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const err = assertBusesNotEmpty(scenario);
+  if (err) return [scenario, err];
+  const busName = Object.keys(scenario.Buses)[0]!;
+  const name = generateUniqueName(scenario["Transmission lines"], "l");
+  return [
+    {
+      ...scenario,
+      "Transmission lines": {
+        ...scenario["Transmission lines"],
+        [name]: {
+          "Source bus": busName,
+          "Target bus": busName,
+          "Susceptance (S)": 1.0,
+          "Normal flow limit (MW)": 1000,
+          "Emergency flow limit (MW)": 1500,
+          "Flow limit penalty ($/MW)": 5000.0,
+        },
+      },
+    },
+    null,
+  ];
+};
+
+export const renameTransmissionLine = (
+  oldName: string,
+  newName: string,
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  const [newLine, err] = renameItemInObject(
+    oldName,
+    newName,
+    scenario["Transmission lines"],
+  );
+  if (err) return [scenario, err];
+
+  // Update transmission line contingencies
+  let newContingencies = scenario["Contingencies"];
+  const contingencyLines = getContingencyTransmissionLines(scenario);
+  if (contingencyLines.has(oldName)) {
+    contingencyLines.delete(oldName);
+    contingencyLines.add(newName);
+    newContingencies = rebuildContingencies(contingencyLines);
+  }
+
+  return [
+    {
+      ...scenario,
+      "Transmission lines": newLine,
+      Contingencies: newContingencies,
+    },
+    null,
+  ];
+};
+
+export const changeTransmissionLineData = (
+  line: string,
+  field: string,
+  newValueStr: string,
+  scenario: UnitCommitmentScenario,
+): [UnitCommitmentScenario, ValidationError | null] => {
+  if (field === "Contingency?") {
+    // Parse boolean value
+    const [newValue, err] = parseBool(newValueStr);
+    if (err) return [scenario, err];
+
+    // Rebuild contingencies
+    const contLines = getContingencyTransmissionLines(scenario);
+    if (newValue) contLines.add(line);
+    else contLines.delete(line);
+    const newContingencies = rebuildContingencies(contLines);
+
+    return [{ ...scenario, Contingencies: newContingencies }, null];
+  } else {
+    const [newLine, err] = changeData(
+      field,
+      newValueStr,
+      scenario["Transmission lines"][line]!,
+      TransmissionLinesColumnSpec,
+      scenario,
+    );
+    if (err) return [scenario, err];
+    return [
+      {
+        ...scenario,
+        "Transmission lines": {
+          ...scenario["Transmission lines"],
+          [line]: newLine as TransmissionLine,
+        },
+      },
+      null,
+    ];
+  }
+};
+
+export const deleteTransmissionLine = (
+  name: string,
+  scenario: UnitCommitmentScenario,
+): UnitCommitmentScenario => {
+  const { [name]: _, ...newLines } = scenario["Transmission lines"];
+
+  // Update transmission line contingencies
+  let newContingencies = scenario["Contingencies"];
+  const contingencyLines = getContingencyTransmissionLines(scenario);
+  if (contingencyLines.has(name)) {
+    contingencyLines.delete(name);
+    newContingencies = rebuildContingencies(contingencyLines);
+  }
+
+  return {
+    ...scenario,
+    "Transmission lines": newLines,
+    Contingencies: newContingencies,
+  };
+};
+
+export const getContingencyTransmissionLines = (
+  scenario: UnitCommitmentScenario,
+): Set<String> => {
+  let result: Set<String> = new Set();
+  Object.entries(scenario.Contingencies).forEach(([name, contingency]) => {
+    if (contingency["Affected lines"].length !== 1)
+      throw Error("not implemented");
+    result.add(contingency["Affected lines"][0]!!);
+  });
+  return result;
+};
+
+export const rebuildContingencies = (
+  contingencyLines: Set<String>,
+): { [name: string]: Contingency } => {
+  const result: { [name: string]: Contingency } = {};
+  contingencyLines.forEach((lineName) => {
+    result[lineName as string] = {
+      "Affected lines": [lineName as string],
+      "Affected generators": [],
+    };
+  });
+  return result;
+};