import { readLines } from "../utils.ts";

export async function solveTask2part1() {
    const lines = await readLines('./2/input.txt');

    let safeReports = 0;
    for (const line of lines) {
        const numbers = line
            .split(' ')
            .map( n => parseInt(n.trim()) );
        
        const checkNumbers = (numbers:number[]) => {
            let order:string|undefined = undefined;
            for (let i = 1; i < numbers.length; i++) {
                const prevN = numbers[i-1];
                const n = numbers[i];
                const diff = n - prevN;
                if (!order) {
                    order = diff < 0 ? 'desc' : 'asc';
                } else {
                    if (order === 'asc' && diff < 0) return false;
                    if (order === 'desc' && diff > 0) return false;
                }
                const diffAbs = Math.abs(diff);
                if (diffAbs < 1) return false;
                if (diffAbs > 3) return false;
            }
            return true;
        }
        const result = checkNumbers(numbers);
        if (result) safeReports++;

    }

    console.log('safeReports', safeReports)
}


export async function solveTask2part2() {
    // const lines = await readLines('./2/exampleInput.txt');
    const lines = await readLines('./2/input.txt');

    let safeReports = 0;
    for (const line of lines) {
        const numbers = line
            .split(' ')
            .map( n => parseInt(n.trim()) );
        
        let badLevelRemoved = false;
        const checkNumbers = (numbers:number[]):boolean => {
            const handleBadLevel = ():boolean => {
                if (badLevelRemoved) return false;
                badLevelRemoved = true;
                const possibilities = new Array(numbers.length).fill(undefined)
                    .map( () => structuredClone(numbers) );
                possibilities.forEach( (n, i) => n.splice(i, 1) );
                
                const anyLvlRmvdWorks = possibilities
                    .map( n => checkNumbers(n) )
                    .some( check => check )

                return anyLvlRmvdWorks;
            }
            let order:string|undefined = undefined;
            for (let i = 1; i < numbers.length; i++) {
                const prevN = numbers[i-1];
                const n = numbers[i];
                const diff = n - prevN;
                if (!order) {
                    order = diff < 0 ? 'desc' : 'asc';
                } else {
                    if (order === 'asc' && diff < 0) return handleBadLevel();
                    if (order === 'desc' && diff > 0) return handleBadLevel();
                }
                const diffAbs = Math.abs(diff);
                if (diffAbs < 1) return handleBadLevel();
                if (diffAbs > 3) return handleBadLevel();
            }
            return true;
        }
        const result = checkNumbers(numbers);
        if (result) safeReports++;

    }

    console.log('safeReports', safeReports)
}