AdventOfCode-ts-2023/5/5_1.ts

import { ExtractNumbers, Inspect, LoadInput } from "../common.ts";

const tests = [
    "seeds: 79 14 55 13",
    "",
    "seed-to-soil map:",
    "50 98 2",
    "52 50 48",
    "",
    "soil-to-fertilizer map:",
    "0 15 37",
    "37 52 2",
    "39 0 15",
    "",
    "fertilizer-to-water map:",
    "49 53 8",
    "0 11 42",
    "42 0 7",
    "57 7 4",
    "",
    "water-to-light map:",
    "88 18 7",
    "18 25 70",
    "",
    "light-to-temperature map:",
    "45 77 23",
    "81 45 19",
    "68 64 13",
    "",
    "temperature-to-humidity map:",
    "0 69 1",
    "1 0 69",
    "",
    "humidity-to-location map:",
    "60 56 37",
    "56 93 4",
];

const input = await LoadInput(5);

// Parse the input
const maps = ParseInput(input);

// Map the seeds
const seeds = maps.Seeds.map((seed) => MapSeed(seed.ID, maps));

// Get the output
let closestLocationID = Number.MAX_SAFE_INTEGER;
if (isSeedMapArray(seeds)) {
     seeds.forEach((seed) => {
        if (seed.LocationID < closestLocationID) { closestLocationID = seed.LocationID; }
    });
}

console.log(`The lowest location ID found is: ${closestLocationID}`);

function ParseInput(almanac: string[]): RangeMaps {
    /** An empty initializer for our output */
    const output: RangeMaps = {
        Seeds: [],
        SeedToSoil: [],
        SoilToFertilizer: [],
        FertilizerToWater: [],
        WaterToLight: [],
        LightToTemperature: [],
        TemperatureToHumidity: [],
        HumidityToLocation: [],
    };

    for (let i = 0; i < almanac.length; i++) {
        let line = almanac[i];

        // Parse the seed ID's
        if (/^seeds:/.test(line)) {
            // Extract all numbers from the line
            const seedIDs = ExtractNumbers(line);
            // Add to the output's Seeds array a new Seed for each number
            seedIDs.forEach((id) => { output.Seeds.push({ID: id}); });
            // Skip the next blank
            i++;
        }
        // Parse the Seed to Soil ranges
        else if (/^seed\-to/.test(line)) {
            output.SeedToSoil = ParseSourceDestinationRange(++i, almanac);
        }
        // Parse the Soil to Fertilizer ranges
        else if (/^soil\-to/.test(line)) {
            output.SoilToFertilizer = ParseSourceDestinationRange(++i, almanac);
        }
        // Parse the Fertilizer to Water ranges
        else if (/^fertilizer\-to/.test(line)) {
            output.FertilizerToWater = ParseSourceDestinationRange(++i, almanac);
        }
        // Parse the Water to Light ranges
        else if (/^water\-to/.test(line)) {
            output.WaterToLight = ParseSourceDestinationRange(++i, almanac);
        }
        // Parse the Light to Temperature ranges
        else if (/^light\-to/.test(line)) {
            output.LightToTemperature = ParseSourceDestinationRange(++i, almanac);
        }
        // Parse the Temperature to Humidity ranges
        else if (/^temperature\-to/.test(line)) {
            output.TemperatureToHumidity = ParseSourceDestinationRange(++i, almanac);
        }
        // Parse the Humidity to Location ranges
        else if (/^humidity\-to/.test(line)) {
            output.HumidityToLocation = ParseSourceDestinationRange(++i, almanac);
        }
    }

    return output;
}

/**
 * Helper function to parse the ranges for each mappable section
 *
 * @param {number} lineNumber The line number to begin parsing from
 * @param {string[]} almanac The complete almanac
 * @returns {MappableObject[]} A list of mapped indices
 */
function ParseSourceDestinationRange(lineNumber: number, almanac: string[]): MappableObject[] {
    const rangeMap: MappableObject[] = [];
    do {
        // Get the values out of the line
        const [destinationRangeStart, sourceRangeStart, rangeLength] = ExtractNumbers(almanac[lineNumber]);
        
        // Create the ranges
        for (let idx = 0; idx < rangeLength; idx++) {
            rangeMap.push({
                ID: sourceRangeStart + idx,
                PointsTo: destinationRangeStart + idx,
            });
        }
    } while(almanac[++lineNumber]);
    
    return rangeMap;
}

/**
 * Find an IdentifiableObject by its ID number
 *
 * @param needle The ID number to find
 * @param haystack The list to find the ID in
 * @returns {IdentifiableObject|undefined} The object by that ID if found, or undefined
 */
function FindObjectByID(needle: number, haystack: IdentifiableObject[]|MappableObject[]): IdentifiableObject|MappableObject|undefined {
    return haystack.find((obj) => obj.ID == needle);
}

/**
 * Map a Seed ID to all of its other attributes
 *
 * Given a seed ID, finds its soil type, fertilizer type, water type,
 * light type, temperature type, humidity type, and location ID.
 *
 * @param {number} seedID 
 * @param {RangeMaps} rangeMaps A parsed map of ranges
 * @returns 
 */
function MapSeed(seedID: number, rangeMaps: RangeMaps): SeedMap|undefined {
    // Make sure the seed with that ID exists before continueing
    if(!FindObjectByID(seedID, rangeMaps.Seeds)) { return undefined; }
    
    // Initialize our seed map object
    const seed: SeedMap = {
        ID: seedID,
        SoilID: 0,
        FertilizerID: 0,
        WaterID: 0,
        LightID: 0,
        TemperatureID: 0,
        HumidityID: 0,
        LocationID: 0,
    };

    seed.SoilID =        (FindObjectByID(seedID, rangeMaps.SeedToSoil) as MappableObject)?.PointsTo || seedID;
    seed.FertilizerID =  (FindObjectByID(seed.SoilID, rangeMaps.SoilToFertilizer) as MappableObject)?.PointsTo || seed.SoilID;
    seed.WaterID =       (FindObjectByID(seed.FertilizerID, rangeMaps.FertilizerToWater) as MappableObject)?.PointsTo || seed.FertilizerID;
    seed.LightID =       (FindObjectByID(seed.WaterID, rangeMaps.WaterToLight) as MappableObject)?.PointsTo || seed.WaterID;
    seed.TemperatureID = (FindObjectByID(seed.LightID, rangeMaps.LightToTemperature) as MappableObject)?.PointsTo|| seed.LightID;
    seed.HumidityID =    (FindObjectByID(seed.TemperatureID, rangeMaps.TemperatureToHumidity) as MappableObject)?.PointsTo || seed.TemperatureID;
    seed.LocationID =    (FindObjectByID(seed.HumidityID, rangeMaps.HumidityToLocation) as MappableObject)?.PointsTo || seed.HumidityID;

    return seed;
}

/**
 * Type guard function to ensure an array is an array of SeedMaps
 *
 * @param {any[]} valueArray The array to check
 * @returns {boolean} Whether the input is an array of SeedMaps or not
 */
function isSeedMapArray(valueArray: any[]): valueArray is SeedMap[] {
    const value = valueArray.shift();

    if (!value || typeof value !== "object") { return false; }

    return Object.hasOwn(value, "ID")
        && Object.hasOwn(value, "SoilID")
        && Object.hasOwn(value, "FertilizerID")
        && Object.hasOwn(value, "WaterID")
        && Object.hasOwn(value, "LightID")
        && Object.hasOwn(value, "TemperatureID")
        && Object.hasOwn(value, "HumidityID")
        && Object.hasOwn(value, "LocationID");
}

/** Any object with a unique identifier */
interface IdentifiableObject {
    /** The ID number for this object */
    ID: number,
};

/** A seed */
interface Seed extends IdentifiableObject {};

/** An IdentifiableObject that points to another IdentifiableObject */
interface MappableObject extends IdentifiableObject {
    /** The ID that this object points to */
    PointsTo: number,
};

/** A complete map of all object IDs and where they point to */
type RangeMaps = {
    /** The list of seed IDs */
    Seeds: Seed[],
    /** The map of seed to soil IDs */
    SeedToSoil: MappableObject[],
    /** The map of soil to fertilizer IDs */
    SoilToFertilizer: MappableObject[],
    /** The map of fertilizer to water IDs */
    FertilizerToWater: MappableObject[],
    /** The map of water to light IDs */
    WaterToLight: MappableObject[],
    /** The map of light to temperature IDs */
    LightToTemperature: MappableObject[],
    /** The map of temperature to humidity IDs */
    TemperatureToHumidity: MappableObject[],
    /** The map of humidity to location IDs */
    HumidityToLocation: MappableObject[],
}

/** A completed map of a seed's property IDs */
type SeedMap = {
    /** The ID of the seed */
    ID: number,
    /** The ID of the soil type the seed needs planted in */
    SoilID: number,
    /** The ID of the fertilizer type the soil needs */
    FertilizerID: number,
    /** The ID of the water type the fertilizer needs */
    WaterID: number,
    /** The ID of the light type the water needs */
    LightID: number,
    /** The ID of the temperature type the light needs */
    TemperatureID: number,
    /** The ID of the humidity type the temperature needs */
    HumidityID: number,
    /** The ID of the location the humidity needs */
    LocationID: number,
}