import { describe, expect, it } from "vitest"

import { dt } from "@scandic-hotels/common/dt"

import { getRelativePastTime } from "./getRelativePastTime"

import type { IntlShape, MessageDescriptor } from "react-intl"

const mockIntl = {
  formatMessage: (
    descriptor: MessageDescriptor,
    values?: Record<string, string | number | boolean | Date>
  ) => {
    const messages: Record<string, string> = {
      "common.nrDaysAgo": `{count, plural, one {# day ago} other {# days ago}}`,
      "common.nrMonthsAgo": `{count, plural, one {# month ago} other {# months ago}}`,
      "common.nrYearsAgo": `{count, plural, one {# year ago} other {# years ago}}`,
    }

    let message: string =
      messages[descriptor.id as string] ||
      (typeof descriptor.defaultMessage === "string"
        ? descriptor.defaultMessage
        : "") ||
      ""

    if (values) {
      // Handle plural forms first
      if (message.includes("{count, plural")) {
        const count = values.count as number
        if (count === 1) {
          // Extract the singular form (between "one {" and "}")
          const singularMatch = message.match(/one {(.*?)}/)
          if (singularMatch) {
            message = singularMatch[1].replace("#", String(count))
          }
        } else {
          // Extract the plural form (between "other {" and "}")
          const pluralMatch = message.match(/other {(.*?)}/)
          if (pluralMatch) {
            message = pluralMatch[1].replace("#", String(count))
          }
        }
      }

      // Replace any remaining placeholders
      Object.entries(values).forEach(([key, value]) => {
        message = message.replace(`{${key}}`, String(value))
      })
    }

    return message
  },
} as IntlShape

describe("getRelativePastTime", () => {
  describe("days ago (1-30 days)", () => {
    it("should return '1 day ago' for yesterday", () => {
      const yesterday = dt().subtract(1, "day").format("YYYY-MM-DD")
      const result = getRelativePastTime(yesterday, mockIntl)

      expect(result).toBe("1 day ago")
    })

    it("should return '2 days ago' for 2 days ago", () => {
      const twoDaysAgo = dt().subtract(2, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(twoDaysAgo, mockIntl)

      expect(result).toBe("2 days ago")
    })

    it("should return '15 days ago' for 15 days ago", () => {
      const fifteenDaysAgo = dt().subtract(15, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(fifteenDaysAgo, mockIntl)

      expect(result).toBe("15 days ago")
    })

    it("should return '30 days ago' for exactly 30 days ago (boundary)", () => {
      const thirtyDaysAgo = dt().subtract(30, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(thirtyDaysAgo, mockIntl)

      expect(result).toBe("30 days ago")
    })

    it("should handle the full range from 1 to 30 days ago", () => {
      for (let days = 1; days <= 30; days++) {
        const pastDate = dt().subtract(days, "days").format("YYYY-MM-DD")
        const result = getRelativePastTime(pastDate, mockIntl)

        if (days === 1) {
          expect(result).toBe("1 day ago")
        } else {
          expect(result).toBe(`${days} days ago`)
        }
      }
    })
  })

  describe("months ago (31-364 days)", () => {
    it("should return '1 month ago' for 31 days ago", () => {
      const thirtyOneDaysAgo = dt().subtract(31, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(thirtyOneDaysAgo, mockIntl)

      expect(result).toBe("1 month ago")
    })

    it("should return '1 month ago' for 45 days ago", () => {
      const fortyFiveDaysAgo = dt().subtract(45, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(fortyFiveDaysAgo, mockIntl)

      expect(result).toBe("1 month ago")
    })

    it("should return '2 months ago' for 60 days ago", () => {
      const sixtyDaysAgo = dt().subtract(60, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(sixtyDaysAgo, mockIntl)

      expect(result).toBe("2 months ago")
    })

    it("should return '6 months ago' for 180 days ago", () => {
      const sixMonthsAgo = dt().subtract(180, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(sixMonthsAgo, mockIntl)

      expect(result).toBe("6 months ago")
    })

    it("should return '11 months ago' for 330 days ago", () => {
      const elevenMonthsAgo = dt().subtract(330, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(elevenMonthsAgo, mockIntl)

      expect(result).toBe("11 months ago")
    })

    it("should return '12 months ago' for 364 days ago (boundary)", () => {
      const twelveMonthsAgo = dt().subtract(364, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(twelveMonthsAgo, mockIntl)

      expect(result).toBe("12 months ago")
    })
  })

  describe("years ago (365+ days)", () => {
    it("should return '1 year ago' for exactly 365 days ago", () => {
      const oneYearAgo = dt().subtract(365, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(oneYearAgo, mockIntl)

      expect(result).toBe("1 year ago")
    })

    it("should return '1 year ago' for 400 days ago", () => {
      const fourHundredDaysAgo = dt().subtract(400, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(fourHundredDaysAgo, mockIntl)

      expect(result).toBe("1 year ago")
    })

    it("should return '2 years ago' for 730 days ago", () => {
      const twoYearsAgo = dt().subtract(730, "days").format("YYYY-MM-DD")
      const result = getRelativePastTime(twoYearsAgo, mockIntl)

      expect(result).toBe("2 years ago")
    })

    it("should return '5 years ago' for 5 years ago", () => {
      const fiveYearsAgo = dt().subtract(5, "years").format("YYYY-MM-DD")
      const result = getRelativePastTime(fiveYearsAgo, mockIntl)

      expect(result).toBe("5 years ago")
    })
  })

  describe("edge cases", () => {
    it("should handle dates with different time components consistently", () => {
      // The function calculates exact day differences, so time components matter
      // Using start of day to ensure consistent results
      const dateWithTime1 = dt()
        .subtract(5, "days")
        .startOf("day")
        .format("YYYY-MM-DD HH:mm")
      const dateWithTime2 = dt()
        .subtract(5, "days")
        .startOf("day")
        .format("YYYY-MM-DD HH:mm")

      const result1 = getRelativePastTime(dateWithTime1, mockIntl)
      const result2 = getRelativePastTime(dateWithTime2, mockIntl)

      expect(result1).toBe("5 days ago")
      expect(result2).toBe("5 days ago")
    })

    it("should handle ISO date strings with timezone", () => {
      const isoDate = dt().subtract(7, "days").toISOString()
      const result = getRelativePastTime(isoDate, mockIntl)

      expect(result).toBe("7 days ago")
    })

    it("should handle future dates (should return 0 days ago for same day)", () => {
      // The function doesn't handle negative days specially - it just uses the diff calculation
      // For future dates on the same day, diff will be 0
      const futureDate = dt().add(1, "day").startOf("day").format("YYYY-MM-DD")
      const result = getRelativePastTime(futureDate, mockIntl)

      expect(result).toBe("0 days ago")
    })
  })

  describe("boundary transitions", () => {
    it("should transition correctly from days to months at 31 days", () => {
      const date30 = dt().subtract(30, "days").format("YYYY-MM-DD")
      const date31 = dt().subtract(31, "days").format("YYYY-MM-DD")

      expect(getRelativePastTime(date30, mockIntl)).toBe("30 days ago")
      expect(getRelativePastTime(date31, mockIntl)).toBe("1 month ago")
    })

    it("should transition correctly from months to years at 365 days", () => {
      const date364 = dt().subtract(364, "days").format("YYYY-MM-DD")
      const date365 = dt().subtract(365, "days").format("YYYY-MM-DD")

      expect(getRelativePastTime(date364, mockIntl)).toBe("12 months ago")
      expect(getRelativePastTime(date365, mockIntl)).toBe("1 year ago")
    })

    it("should handle the transition from 1 day to multiple days", () => {
      const date1 = dt().subtract(1, "day").format("YYYY-MM-DD")
      const date2 = dt().subtract(2, "days").format("YYYY-MM-DD")

      expect(getRelativePastTime(date1, mockIntl)).toBe("1 day ago")
      expect(getRelativePastTime(date2, mockIntl)).toBe("2 days ago")
    })
  })
})