import {sleep} from 'k6';
import {SharedArray} from 'k6/data';
import exec from 'k6/execution';
import logging from 'k6/x/frostfs/logging';
import registry from 'k6/x/frostfs/registry';
import s3 from 'k6/x/frostfs/s3';
import stats from 'k6/x/frostfs/stats';

import {generateS3Key} from './libs/keygen.js';
import {newGenerator} from './libs/datagen.js';
import {parseEnv} from './libs/env-parser.js';
import {textSummary} from './libs/k6-summary-0.0.2.js';

parseEnv();

const obj_list = new SharedArray(
    'obj_list',
    function() { return JSON.parse(open(__ENV.PREGEN_JSON)).objects; });

const bucket_list = new SharedArray(
    'bucket_list',
    function() { return JSON.parse(open(__ENV.PREGEN_JSON)).buckets; });

const read_size = JSON.parse(open(__ENV.PREGEN_JSON)).obj_size;
const summary_json = __ENV.SUMMARY_JSON || '/tmp/summary.json';

const no_verify_ssl = __ENV.NO_VERIFY_SSL || 'true';

const connection_args = {
    no_verify_ssl : no_verify_ssl
}
// Select random S3 endpoint for current VU
const s3_endpoints = __ENV.S3_ENDPOINTS.split(',');
const s3_endpoint =
    s3_endpoints[Math.floor(Math.random() * s3_endpoints.length)];
const s3_client = s3.connect(s3_endpoint, connection_args);
const log = logging.new().withField('endpoint', s3_endpoint);

const registry_enabled = !!__ENV.REGISTRY_FILE;
const obj_registry =
    registry_enabled ? registry.open(__ENV.REGISTRY_FILE) : undefined;

const duration = __ENV.DURATION;

if (!!__ENV.METRIC_TAGS) {
    stats.setTags(__ENV.METRIC_TAGS)
}

const read_age = __ENV.READ_AGE ? parseInt(__ENV.READ_AGE) : 10;
let obj_to_read_selector = undefined;
if (registry_enabled) {
    obj_to_read_selector = registry.getSelector(
        __ENV.REGISTRY_FILE, 'obj_to_read',
        __ENV.SELECTION_SIZE ? parseInt(__ENV.SELECTION_SIZE) : 0, {
            status : 'created',
            age : read_age,
        })
}

const scenarios = {};

const write_vu_count = parseInt(__ENV.WRITERS || '0');
const generator = newGenerator(write_vu_count > 0);
if (write_vu_count > 0) {
    scenarios.write = {
        executor : 'constant-vus',
        vus : write_vu_count,
        duration : `${duration}s`,
        exec : 'obj_write',
        gracefulStop : '5s',
    };
}

const read_vu_count = parseInt(__ENV.READERS || '0');
if (read_vu_count > 0) {
    scenarios.read = {
        executor : 'constant-vus',
        vus : read_vu_count,
        duration : `${duration}s`,
        exec : 'obj_read',
        gracefulStop : '5s',
    };
}

const delete_age = __ENV.DELETE_AGE ? parseInt(__ENV.DELETE_AGE) : undefined;
let obj_to_delete_selector = undefined;
let obj_to_delete_exit_on_null = undefined;

if (registry_enabled ) {
    obj_to_delete_exit_on_null = (write_vu_count == 0) && (read_vu_count == 0)

    let constructor = obj_to_delete_exit_on_null ? registry.getOneshotSelector
        : registry.getSelector;

    obj_to_delete_selector =
        constructor(__ENV.REGISTRY_FILE, 'obj_to_delete',
            __ENV.SELECTION_SIZE ? parseInt(__ENV.SELECTION_SIZE) : 0, {
                status : 'read',
                age : delete_age,
            });
}



const delete_vu_count = parseInt(__ENV.DELETERS || '0');
if (delete_vu_count > 0) {
    if (!obj_to_delete_selector) {
        throw 'Positive DELETE worker number without a proper object selector';
    }

    scenarios.delete = {
        executor : 'constant-vus',
        vus : delete_vu_count,
        duration : `${duration}s`,
        exec : 'obj_delete',
        gracefulStop : '5s',
    };
}

export const options = {
    scenarios,
    setupTimeout : '5s',
};

export function setup() {
    const total_vu_count = write_vu_count + read_vu_count + delete_vu_count;

    console.log(`Pregenerated buckets:          ${bucket_list.length}`);
    console.log(`Pregenerated read object size: ${read_size}`);
    console.log(`Pregenerated total objects:    ${obj_list.length}`);
    console.log(`Reading VUs:                   ${read_vu_count}`);
    console.log(`Writing VUs:                   ${write_vu_count}`);
    console.log(`Deleting VUs:                  ${delete_vu_count}`);
    console.log(`Total VUs:                     ${total_vu_count}`);

    const start_timestamp = Date.now()
    console.log(
        `Load started at:               ${Date(start_timestamp).toString()}`)
}

export function teardown(data) {
    if (obj_registry) {
        obj_registry.close();
    }
    const end_timestamp = Date.now()
    console.log(
        `Load finished at:              ${Date(end_timestamp).toString()}`)
}

export function handleSummary(data) {
    return {
        'stdout' : textSummary(data, {indent : ' ', enableColors : false}),
        [summary_json] : JSON.stringify(data),
    };
}

export function obj_write() {
    if (__ENV.SLEEP_WRITE) {
        sleep(__ENV.SLEEP_WRITE);
    }

    const key = generateS3Key();
    const bucket = bucket_list[Math.floor(Math.random() * bucket_list.length)];

    const payload = generator.genPayload();
    const resp = s3_client.put(bucket, key, payload);
    if (!resp.success) {
        log.withFields({bucket : bucket, key : key}).error(resp.error);
        return;
    }

    if (obj_registry) {
        obj_registry.addObject('', '', bucket, key, payload.hash());
    }
}

export function obj_read() {
    if (__ENV.SLEEP_READ) {
        sleep(__ENV.SLEEP_READ);
    }

    if (obj_to_read_selector) {
        const obj = obj_to_read_selector.nextObject();
        if (!obj  ) {
            return;
        }
        const resp = s3_client.get(obj.s3_bucket, obj.s3_key)
        if (!resp.success) {
            log.withFields({bucket : obj.s3_bucket, key : obj.s3_key, status: obj.status, op: `READ`})
                .error(resp.error);
        } else {
            obj_registry.setObjectStatus(obj.id, obj.status, 'read');
        }

        return
    }

    const obj = obj_list[Math.floor(Math.random() * obj_list.length)];

    const resp = s3_client.get(obj.bucket, obj.object);
    if (!resp.success) {
        log.withFields({bucket : obj.bucket, key : obj.object}).error(resp.error);
    } else {
        obj_registry.setObjectStatus(obj.id, obj.status, 'read');
    }
}

export function obj_delete() {
    if (__ENV.SLEEP_DELETE) {
        sleep(__ENV.SLEEP_DELETE);
    }

    const obj = obj_to_delete_selector.nextObject();
    delete_object(obj)
}

export function delete_object(obj) {
    if (!obj) {
        if (obj_to_delete_exit_on_null) {
            exec.test.abort("No more objects to select");
        }
        return;
    }

    const resp = s3_client.delete(obj.s3_bucket, obj.s3_key);
    if (!resp.success) {
        log.withFields({bucket : obj.s3_bucket, key : obj.s3_key, op : 'DELETE'})
            .error(resp.error);
        return;
    }

    obj_registry.deleteObject(obj.id);
}