/*
 * Copyright (c) 2023 New Vector Ltd
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.element.android.libraries.dateformatter.impl

import com.google.common.truth.Truth.assertThat
import io.element.android.libraries.dateformatter.api.LastMessageTimestampFormatter
import io.element.android.libraries.dateformatter.test.FakeClock
import kotlinx.datetime.Instant
import kotlinx.datetime.TimeZone
import org.junit.Test
import java.util.Locale

class DefaultLastMessageTimestampFormatterTest {
    @Test
    fun `test null`() {
        val now = "1980-04-06T18:35:24.00Z"
        val formatter = createFormatter(now)
        assertThat(formatter.format(null)).isEmpty()
    }

    @Test
    fun `test epoch`() {
        val now = "1980-04-06T18:35:24.00Z"
        val formatter = createFormatter(now)
        assertThat(formatter.format(0)).isEqualTo("01.01.1970")
    }

    @Test
    fun `test now`() {
        val now = "1980-04-06T18:35:24.00Z"
        val dat = "1980-04-06T18:35:24.00Z"
        val formatter = createFormatter(now)
        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("18:35")
    }

    @Test
    fun `test one second before`() {
        val now = "1980-04-06T18:35:24.00Z"
        val dat = "1980-04-06T18:35:23.00Z"
        val formatter = createFormatter(now)
        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("18:35")
    }

    @Test
    fun `test one minute before`() {
        val now = "1980-04-06T18:35:24.00Z"
        val dat = "1980-04-06T18:34:24.00Z"
        val formatter = createFormatter(now)
        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("18:34")
    }

    @Test
    fun `test one hour before`() {
        val now = "1980-04-06T18:35:24.00Z"
        val dat = "1980-04-06T17:35:24.00Z"
        val formatter = createFormatter(now)
        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("17:35")
    }

    @Test
    fun `test one day before same time`() {
        val now = "1980-04-06T18:35:24.00Z"
        val dat = "1980-04-05T18:35:24.00Z"
        val formatter = createFormatter(now)
        // TODO DateUtils.getRelativeTimeSpanString returns null.
        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("")
    }

    @Test
    fun `test one month before same time`() {
        val now = "1980-04-06T18:35:24.00Z"
        val dat = "1980-03-06T18:35:24.00Z"
        val formatter = createFormatter(now)
        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("6 Mar")
    }

    @Test
    fun `test one year before same time`() {
        val now = "1980-04-06T18:35:24.00Z"
        val dat = "1979-04-06T18:35:24.00Z"
        val formatter = createFormatter(now)
        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("06.04.1979")
    }

    /**
     * Create DefaultLastMessageFormatter and set current time to the provided date.
     */
    private fun createFormatter(@Suppress("SameParameterValue") currentDate: String): LastMessageTimestampFormatter {
        val clock = FakeClock().apply { givenInstant(Instant.parse(currentDate)) }
        val localDateTimeProvider = LocalDateTimeProvider(clock, TimeZone.UTC)
        val dateFormatters = DateFormatters(Locale.US, clock, TimeZone.UTC)
        return DefaultLastMessageTimestampFormatter(localDateTimeProvider, dateFormatters)
    }
}
