import { parser } from "./sol1";

const reports = parser("input.txt");

const checkBadReport = (report: number[]) => {
    const freqMap: Record<string, number[]> = {}

    const getProps = (i: number, j: number) => {
        const equality = report[i] < report[j] ? "increasing": report[i] > report[j] ? "decreasing": "equal"
        const valid = Math.abs(report[i] - report[j]) >= 1 && Math.abs(report[i] - report[j]) <= 3

        return [valid, equality] as [boolean, string]
    }

    for (let i = 0; i < report.length - 1; i++) {
        const props = JSON.stringify(getProps(i, i + 1))
        if (!(props in freqMap)) freqMap[props] = []
        freqMap[props].push(i)
    }

    if (Object.keys(freqMap).length < 2) return JSON.parse(Object.keys(freqMap)[0])[0]
    if (Object.keys(freqMap).length > 2) return false


    for (let props in freqMap) {
        if (freqMap[props].length === 1) {
            const otherProp = Object.keys(freqMap).find(k => k !== props)!
            const i = freqMap[props][0]
            const condition = (i: number) => (i <= 0 || i >= report.length - 1 || JSON.stringify(getProps(i - 1, i + 1)) === otherProp)
            if (condition(i) || condition(i + 1)) {
                return JSON.parse(otherProp)[0]
            }
        }
    }

    return false
}

const ans = reports.reduce<number>((ans, report) => {
    return checkBadReport(report) ? ans += 1 : ans
}, 0);

console.log(ans);