import { ColumnMetadata } from "../metadata/ColumnMetadata"
import { parseISO } from "date-fns"

/**
 * Provides utilities to transform hydrated and persisted data.
 */
export class DateUtils {
    // -------------------------------------------------------------------------
    // Public Static Methods
    // -------------------------------------------------------------------------

    /**
     * Normalizes date object hydrated from the database.
     */
    static normalizeHydratedDate(
        mixedDate: Date | string | undefined,
    ): Date | string | undefined {
        if (!mixedDate) return mixedDate

        return typeof mixedDate === "string"
            ? new Date(mixedDate)
            : (mixedDate as Date)
    }

    /**
     * Converts given value into date string in a "YYYY-MM-DD" format.
     */
    static mixedDateToDateString(value: string | Date): string {
        if (value instanceof Date) {
            return (
                this.formatZerolessValue(value.getFullYear(), 4) +
                "-" +
                this.formatZerolessValue(value.getMonth() + 1) +
                "-" +
                this.formatZerolessValue(value.getDate())
            )
        }

        return value
    }

    /**
     * Converts given value into date object.
     */
    static mixedDateToDate(
        mixedDate: Date | string,
        toUtc: boolean = false,
        useMilliseconds = true,
    ): Date {
        /**
         * new Date(ISOString) is not a reliable parser to date strings.
         * It's better to use 'date-fns' parser to parser string in ISO Format.
         *
         * The problem here is with wrong timezone.
         *
         * For example:
         *
         * ``new Date('2021-04-28')`` will generate `2021-04-28T00:00:00.000Z`
         * in my timezone, which is not true for my timezone (GMT-0300). It should
         * be `2021-04-28T03:00:00.000Z` as `new Date(2021, 3, 28)` generates.
         *
         * https://stackoverflow.com/a/2587398
         */
        let date =
            typeof mixedDate === "string" ? parseISO(mixedDate) : mixedDate

        if (toUtc)
            date = new Date(
                date.getUTCFullYear(),
                date.getUTCMonth(),
                date.getUTCDate(),
                date.getUTCHours(),
                date.getUTCMinutes(),
                date.getUTCSeconds(),
                date.getUTCMilliseconds(),
            )

        if (!useMilliseconds) date.setUTCMilliseconds(0)

        return date
    }

    /**
     * Converts given value into time string in a "HH:mm:ss" format.
     */
    static mixedDateToTimeString(
        value: Date | any,
        skipSeconds: boolean = false,
    ): string | any {
        if (value instanceof Date)
            return (
                this.formatZerolessValue(value.getHours()) +
                ":" +
                this.formatZerolessValue(value.getMinutes()) +
                (!skipSeconds
                    ? ":" + this.formatZerolessValue(value.getSeconds())
                    : "")
            )

        return value
    }

    /**
     * Converts given value into time string in a "HH:mm:ss" format.
     */
    static mixedTimeToDate(value: Date | any): string | any {
        if (typeof value === "string") {
            const [hours, minutes, seconds] = value.split(":")
            const date = new Date()
            if (hours) date.setHours(parseInt(hours))
            if (minutes) date.setMinutes(parseInt(minutes))
            if (seconds) date.setSeconds(parseInt(seconds))
            return date
        }

        return value
    }

    /**
     * Converts given string value with "-" separator into a "HH:mm:ss" format.
     */
    static mixedTimeToString(
        value: string | any,
        skipSeconds: boolean = false,
    ): string | any {
        value =
            value instanceof Date
                ? value.getHours() +
                  ":" +
                  value.getMinutes() +
                  (!skipSeconds ? ":" + value.getSeconds() : "")
                : value
        if (typeof value === "string") {
            return value
                .split(":")
                .map((v) => (v.length === 1 ? "0" + v : v)) // append zero at beginning if we have a first-zero-less number
                .join(":")
        }

        return value
    }

    /**
     * Converts given value into datetime string in a "YYYY-MM-DD HH-mm-ss" format.
     */
    static mixedDateToDatetimeString(
        value: Date | any,
        useMilliseconds?: boolean,
    ): string | any {
        if (typeof value === "string") {
            value = new Date(value)
        }
        if (value instanceof Date) {
            let finalValue =
                this.formatZerolessValue(value.getFullYear(), 4) +
                "-" +
                this.formatZerolessValue(value.getMonth() + 1) +
                "-" +
                this.formatZerolessValue(value.getDate()) +
                " " +
                this.formatZerolessValue(value.getHours()) +
                ":" +
                this.formatZerolessValue(value.getMinutes()) +
                ":" +
                this.formatZerolessValue(value.getSeconds())

            if (useMilliseconds)
                finalValue += `.${this.formatMilliseconds(
                    value.getMilliseconds(),
                )}`

            value = finalValue
        }

        return value
    }

    /**
     * Converts given value into utc datetime string in a "YYYY-MM-DD HH-mm-ss.sss" format.
     */
    static mixedDateToUtcDatetimeString(value: Date | any): string | any {
        if (typeof value === "string") {
            value = new Date(value)
        }
        if (value instanceof Date) {
            return (
                this.formatZerolessValue(value.getUTCFullYear(), 4) +
                "-" +
                this.formatZerolessValue(value.getUTCMonth() + 1) +
                "-" +
                this.formatZerolessValue(value.getUTCDate()) +
                " " +
                this.formatZerolessValue(value.getUTCHours()) +
                ":" +
                this.formatZerolessValue(value.getUTCMinutes()) +
                ":" +
                this.formatZerolessValue(value.getUTCSeconds()) +
                "." +
                this.formatMilliseconds(value.getUTCMilliseconds())
            )
        }

        return value
    }

    /**
     * Converts each item in the given array to string joined by "," separator.
     */
    static simpleArrayToString(value: any[] | any): string[] | any {
        if (Array.isArray(value)) {
            return (value as any[]).map((i) => String(i)).join(",")
        }

        return value
    }

    /**
     * Converts given string to simple array split by "," separator.
     */
    static stringToSimpleArray(value: string | any): string | any {
        if (typeof value === "string") {
            if (value.length > 0) {
                return value.split(",")
            } else {
                return []
            }
        }

        return value
    }

    static simpleJsonToString(value: any): string {
        return JSON.stringify(value)
    }

    static stringToSimpleJson(value: any) {
        return typeof value === "string" ? JSON.parse(value) : value
    }

    static simpleEnumToString(value: any) {
        return "" + value
    }

    static stringToSimpleEnum(value: any, columnMetadata: ColumnMetadata) {
        if (
            columnMetadata.enum &&
            !isNaN(value) &&
            columnMetadata.enum.indexOf(parseInt(value)) >= 0
        ) {
            // convert to number if that exists in poosible enum options
            value = parseInt(value)
        }

        return value
    }

    // -------------------------------------------------------------------------
    // Private Static Methods
    // -------------------------------------------------------------------------

    /**
     * Formats given number to "0x" format, e.g. if the totalLength = 2 and the value is 1 then it will return "01".
     */
    private static formatZerolessValue(value: number, totalLength = 2): string {
        const pad = "0".repeat(totalLength)

        return String(`${pad}${value}`).slice(-totalLength)
    }

    /**
     * Formats given number to "0x" format, e.g. if it is 1 then it will return "01".
     */
    private static formatMilliseconds(value: number): string {
        if (value < 10) {
            return "00" + value
        } else if (value < 100) {
            return "0" + value
        } else {
            return String(value)
        }
    }
}