/*
 * Copyright OpenSearch Contributors
 * SPDX-License-Identifier: Apache-2.0
 */

package org.opensearch.indexmanagement.indexstatemanagement.validation

import org.opensearch.indexmanagement.indexstatemanagement.IndexStateManagementRestTestCase
import org.opensearch.indexmanagement.indexstatemanagement.model.Policy
import org.opensearch.indexmanagement.indexstatemanagement.model.State
import org.opensearch.indexmanagement.indexstatemanagement.randomErrorNotification
import org.opensearch.indexmanagement.spi.indexstatemanagement.Validate
import org.opensearch.indexmanagement.waitFor
import java.time.Instant
import java.time.temporal.ChronoUnit
import java.util.Locale

class ValidateForceMergeIT : IndexStateManagementRestTestCase() {

    private val testIndexName = javaClass.simpleName.lowercase(Locale.ROOT)

    fun `test basic workflow`() {
        enableValidationService()
        val indexName = "${testIndexName}_index_1"
        val policyID = "${testIndexName}_testPolicyName_1"

        // Create a Policy with one State that only preforms a force_merge Action
        val forceMergeActionConfig = org.opensearch.indexmanagement.indexstatemanagement.action.ForceMergeAction(maxNumSegments = 1, index = 0)
        val states = listOf(State("ForceMergeState", listOf(forceMergeActionConfig), listOf()))

        val policy = Policy(
            id = policyID,
            description = "$testIndexName description",
            schemaVersion = 1L,
            lastUpdatedTime = Instant.now().truncatedTo(ChronoUnit.MILLIS),
            errorNotification = randomErrorNotification(),
            defaultState = states[0].name,
            states = states
        )

        createPolicy(policy, policyID)
        createIndex(indexName, policyID)

        // Add sample data to increase segment count, passing in a delay to ensure multiple segments get created
        insertSampleData(indexName, 3, 1000)

        waitFor { assertTrue("Segment count for [$indexName] was less than expected", validateSegmentCount(indexName, min = 2)) }

        val managedIndexConfig = getExistingManagedIndexConfig(indexName)

        // Will change the startTime each execution so that it triggers in 2 seconds
        // First execution: Policy is initialized
        updateManagedIndexConfigStartTime(managedIndexConfig)

        waitFor { assertEquals(policyID, getExplainManagedIndexMetaData(indexName).policyID) }

        // Second execution: Index is set to read-only for force_merge
        updateManagedIndexConfigStartTime(managedIndexConfig)

        waitFor { assertEquals("true", getIndexBlocksWriteSetting(indexName)) }

        // Third execution: Force merge operation is kicked off
        updateManagedIndexConfigStartTime(managedIndexConfig)

        // verify we set maxNumSegments in action properties when kicking off force merge
        waitFor {
            val data = getExplainValidationResult(indexName)
            assertEquals(
                "Index force_merge action validation status is RE_VALIDATING.",
                Validate.ValidationStatus.PASSED,
                data.validationStatus
            )
            assertEquals(
                "Index force_merge action validation status is RE_VALIDATING.",
                ValidateForceMerge.getValidationPassedMessage(indexName),
                data.validationMessage
            )
        }
        waitFor {
            assertEquals(
                "maxNumSegments not set in ActionProperties",
                forceMergeActionConfig.maxNumSegments,
                getExplainManagedIndexMetaData(indexName).actionMetaData?.actionProperties?.maxNumSegments
            )
        }

        // Fourth execution: Waits for force merge to complete, which will happen in this execution since index is small
        updateManagedIndexConfigStartTime(managedIndexConfig)

        waitFor { assertTrue("Segment count for [$indexName] after force merge is incorrect", validateSegmentCount(indexName, min = 1, max = 1)) }
        // verify we reset actionproperties at end of forcemerge
        waitFor { assertNull("maxNumSegments was not reset", getExplainManagedIndexMetaData(indexName).actionMetaData?.actionProperties) }
        // index should still be readonly after force merge finishes
        waitFor { assertEquals("true", getIndexBlocksWriteSetting(indexName)) }
    }
}