<?php

/**
 * Tirreno ~ Open source user analytics
 * Copyright (c) Tirreno Technologies Sàrl (https://www.tirreno.com)
 *
 * Licensed under GNU Affero General Public License version 3 of the or any later version.
 * For full copyright and license information, please see the LICENSE
 * Redistributions of files must retain the above copyright notice.
 *
 * @copyright     Copyright (c) Tirreno Technologies Sàrl (https://www.tirreno.com)
 * @license       https://opensource.org/licenses/AGPL-3.0 AGPL License
 * @link          https://www.tirreno.com Tirreno(tm)
 */

namespace Controllers\Admin\Rules;

class Data extends \Controllers\Base {
    use \Traits\ApiKeys;

    private \Controllers\Admin\Context\Data $contextController;
    private \Controllers\Admin\User\Data $userController;
    private \Models\OperatorsRules $rulesModel;

    private array $totalModels;
    private array $rulesMap;

    public function proceedPostRequest(array $params): array {
        return match ($params['cmd']) {
            'changeThresholdValues' => $this->changeThresholdValues($params),
            'refreshRules' => $this->refreshRules($params),
            default => []
        };
    }

    private function refreshRules(array $params): array {
        $pageParams = [];
        $errorCode = $this->validateRefreshRules($params);

        if ($errorCode) {
            $pageParams['ERROR_CODE'] = $errorCode;
        } else {
            $model = new \Models\Rules();

            // get all rules from db by uid; will not return classes with filename mismatch or invalid classname
            $currentRules   = $model->getAll();

            $sortedRules = [];
            foreach ($currentRules as $rule) {
                $sortedRules[$rule['uid']] = $rule;
            }

            $localClasses   = \Utils\RulesClasses::getRulesClasses(false);
            $mainClasses    = \Utils\RulesClasses::getRulesClasses(true);

            $iterates       = [[], [], [], [], [], []];
            $metUids        = [];

            $parentClass = \Controllers\Admin\Rules\Set\BaseRule::class;
            $mtd         = 'defineCondition';

            // local classes first to keep ability to override default classes
            $allClassesFromFiles = $localClasses['imported'] + $mainClasses['imported'];

            foreach ($allClassesFromFiles as $uid => $cls) {
                $valid = true;

                $name   = constant("$cls::NAME") ?? '';
                $descr  = constant("$cls::DESCRIPTION") ?? '';
                $attr   = constant("$cls::ATTRIBUTES") ?? [];

                $obj = [
                    'uid'           => $uid,
                    'name'          => $name,
                    'descr'         => $descr,
                    'attributes'    => $attr,
                ];

                // check constants
                if (!is_string($name) || !is_string($descr) || !is_array($attr)) {
                    $valid = false;
                    $obj['name']        = '';
                    $obj['descr']       = '';
                    $obj['attributes']  = [];
                // check if rule is child class of BaseRule and defineCondition() was implemented
                } elseif (!is_subclass_of($cls, $parentClass) || (new \ReflectionMethod($cls, $mtd))->isAbstract()) {
                    $valid = false;
                }

                $status = $this->addRule($sortedRules, $obj, $valid, $model);
                $iterates[($status === null ? 0 : 1 + intval($status)) * 2 + intval($valid)][] = $uid;
                $metUids[] = $uid;
            }

            $flipMetUids = array_flip($metUids);
            $newMissingRules = [];
            $oldMissingCnt = 0;
            foreach ($sortedRules as $uid => $rule) {
                if (!array_key_exists($uid, $flipMetUids)) {
                    if (!$rule['missing']) {
                        $newMissingRules[$uid] = $rule;
                        $model->setMissingByUid($uid);
                    } else {
                        $oldMissingCnt += 1;
                    }
                }
            }

            //$successCnt = count($iterates[5]) + count($iterates[3]);
            //$warningCnt = count($iterates[4]) + count($iterates[2]);

            $newValidCnt    = count($iterates[5]);
            $newInvalidCnt  = count($iterates[4]);
            $updValidCnt    = count($iterates[3]);
            $updInvalidCnt  = count($iterates[2]);
            $missingCnt     = count($newMissingRules);

            $messages = [];

            $messages[] = $this->getStatusNotification($newValidCnt, 'Added %s rule%s: %s', $iterates[5]);
            $messages[] = $this->getStatusNotification($updValidCnt, 'Updated %s rule%s: %s', $iterates[3]);

            $msg = join(";\n", array_filter($messages));

            if ($msg) {
                $pageParams['SUCCESS_MESSAGE'] = $msg;
            }

            $messages = [];

            $messages[] = $this->getStatusNotification($newInvalidCnt, 'Added %s invalid rule%s: %s', $iterates[4]);
            $messages[] = $this->getStatusNotification($updInvalidCnt, 'Updated %s invalid rule%s: %s', $iterates[2]);
            $messages[] = $this->getStatusNotification($missingCnt, 'Missing %s rule%s: %s', array_column($newMissingRules, 'uid'));

            $msg = join(";\n", array_filter($messages));

            if ($msg) {
                $pageParams['ERROR_MESSAGE'] = $msg;
            }

            if (!array_key_exists('ERROR_MESSAGE', $pageParams) && !array_key_exists('SUCCESS_MESSAGE', $pageParams)) {
                $activeCnt      = count($iterates[1]);
                $invalidCnt     = count($iterates[0]);

                $msg = sprintf('Rules refreshed (%s rule%s active', $activeCnt, ($activeCnt > 1 ? 's' : ''));
                if ($invalidCnt) {
                    $msg .= sprintf(', %s invalid', $invalidCnt);
                }
                if ($oldMissingCnt) {
                    $msg .= sprintf(', %s missing', $oldMissingCnt);
                }

                $msg .= ')';
                $pageParams['SUCCESS_MESSAGE'] = $msg;
            }
        }

        return $pageParams;
    }

    private function getStatusNotification(int $cnt, string $template, array $data): ?string {
        if (!$cnt) {
            return null;
        }

        $s = join(', ', array_slice($data, 0, 10, true)) . ($cnt > 10 ? '&hellip;' : '.');

        return sprintf($template, strval($cnt), ($cnt > 1 ? 's' : ''), $s);
    }

    private function addRule(array $existingArray, array $obj, bool $valid, \Models\Rules $model): ?bool {
        $data = $existingArray[$obj['uid']] ?? null;
        $r = null;

        sort($obj['attributes']);

        if ($data === null) {
            $r = true;
        } else {
            $data['attributes'] = json_decode($data['attributes']);
            sort($data['attributes']);

            foreach ($obj as $key => $value) {
                if ($value !== $data[$key]) {
                    $r = false;
                    break;
                }
            }

            if ($r !== false && $data['validated'] !== $valid) {
                $r = false;
            }
        }

        if ($r !== null || $data['missing']) {
            $model->addRule($obj['uid'], $obj['name'], $obj['descr'], $obj['attributes'], $valid);
        }

        return ($data !== null && $data['missing']) ? true : $r;
    }

    private function validateRefreshRules(array $params): int|false {
        $errorCode = \Utils\Access::CSRFTokenValid($params, $this->f3);
        if ($errorCode) {
            return $errorCode;
        }

        return false;
    }

    public function changeThresholdValues(array $params): array {
        $pageParams = [];
        $errorCode = $this->validateThresholdValues($params);

        if ($errorCode) {
            $pageParams['ERROR_CODE'] = $errorCode;
        } else {
            $keyId = isset($params['keyId']) ? (int) $params['keyId'] : null;

            $model = new \Models\ApiKeys();
            $model->getKeyById($keyId);

            $blacklistThreshold = (int) ($params['blacklist-threshold'] ?? -1);
            $reviewQueueThreshold = (int) ($params['review-queue-threshold'] ?? 0);

            $recalculateReviewQueueCnt = $model->review_queue_threshold !== $reviewQueueThreshold;

            $model->updateBlacklistThreshold($blacklistThreshold);
            $model->updateReviewQueueThreshold($reviewQueueThreshold);

            if ($recalculateReviewQueueCnt) {
                $controller = new \Controllers\Admin\ReviewQueue\Data();
                $controller->getNumberOfNotReviewedUsers($keyId, false, true);
            }

            $pageParams['SUCCESS_MESSAGE'] = $this->f3->get('AdminThresholdValues_update_success_message');
        }

        return $pageParams;
    }

    private function validateThresholdValues(array $params): int|false {
        $errorCode = \Utils\Access::CSRFTokenValid($params, $this->f3);
        if ($errorCode) {
            return $errorCode;
        }

        $keyId = isset($params['keyId']) ? (int) $params['keyId'] : null;
        if (!$keyId) {
            return \Utils\ErrorCodes::API_KEY_ID_DOESNT_EXIST;
        }

        if ($keyId !== $this->getCurrentOperatorApiKeyId()) {
            return \Utils\ErrorCodes::API_KEY_WAS_CREATED_FOR_ANOTHER_USER;
        }

        $blacklistThreshold = (int) ($params['blacklist-threshold'] ?? -1);
        if ($blacklistThreshold < -1 || $blacklistThreshold > 18) {
            return \Utils\ErrorCodes::BLACKLIST_THRESHOLD_DOES_NOT_EXIST;
        }

        $reviewQueueThreshold = (int) ($params['review-queue-threshold'] ?? 0);
        if ($reviewQueueThreshold < 0 || $reviewQueueThreshold > 100) {
            return \Utils\ErrorCodes::REVIEW_QUEUE_THRESHOLD_DOES_NOT_EXIST;
        }

        if ($reviewQueueThreshold <= $blacklistThreshold) {
            return \Utils\ErrorCodes::BLACKLIST_THRESHOLD_EXCEEDS_REVIEW_QUEUE_THRESHOLD;
        }

        return false;
    }

    public function getRulesForLoggedUser(): array {
        $apiKey = $this->getCurrentOperatorApiKeyId();

        return $this->getAllAttrFilteredRulesByApiKey($apiKey);
    }

    public function saveUserRule(string $ruleUid, int $score): void {
        $apiKey = $this->getCurrentOperatorApiKeyId();
        $model = new \Models\OperatorsRules();
        $model->updateRule($ruleUid, $score, $apiKey);
    }

    public function saveRuleProportion(string $ruleUid, float $proportion): void {
        $apiKey = $this->getCurrentOperatorApiKeyId();
        $model = new \Models\OperatorsRules();
        $model->updateRuleProportion($ruleUid, $proportion, $apiKey);
    }

    public function getRuleProportion(int $totalUsers, int $ruleUsers): float {
        if ($ruleUsers === 0 || $totalUsers === 0) {
            return 0.0;
        }

        $proportion = (float) (100 * $ruleUsers) / (float) $totalUsers;

        // if number is too small make it a bit greater so it will be written in db as 0 < n < 1
        return abs($proportion) < 0.001 ? 0.001 : $proportion;
    }

    // return array of uids on each account of triggered rules
    private function evaluateRules(array $accountIds, array $rules, int $apiKey): array {
        $result = array_fill_keys($accountIds, []);

        $context = [];
        $record = [];

        foreach (array_chunk($accountIds, \Utils\Variables::getRuleUsersBatchSize()) as $batch) {
            $context = $this->contextController->getContextByAccountIds($batch, $apiKey);
            foreach ($batch as $user) {
                $record = $context[$user] ?? null;
                if ($record) {
                    foreach ($rules as $rule) {
                        if ($this->executeRule($rule, $record)) {
                            $result[$user][] = $rule->uid;
                        }
                    }
                }
            }
        }

        return $result;
    }

    private function executeRule(Set\BaseRule $rule, array $params): bool {
        $executed = false;

        try {
            $rule->updateParams($params);
            $executed = $rule->execute();
        } catch (\Throwable $e) {
            if (defined($rule->uid)) {
                $model = new \Models\Rules();
                $model->setInvalidByUid($rule->uid);
            }

            error_log('Failed to execute rule class ' . $rule->uid . ': ' . $e->getMessage());
        }

        return $executed;
    }

    public function checkRule(string $ruleUid): array {
        $apiKey = $this->getCurrentOperatorApiKeyId();

        $model = new \Models\Users();
        $users = $model->getAllUsersIdsOrdered($apiKey);
        $accounts = [];
        foreach ($users as $user) {
            $accounts[$user['accountid']] = $user;
        }
        $accountIds = array_keys($accounts);

        $this->buildEvaluationModels($ruleUid);

        $targetRule = $this->rulesModel->getRuleWithOperatorValue($ruleUid, $apiKey);

        if ($targetRule === [] || !array_key_exists($ruleUid, $this->rulesMap)) {
            return [0, []];
        }

        $results = $this->evaluateRules($accountIds, [$this->rulesMap[$ruleUid]], $apiKey);
        $matchingAccountIds = array_keys(array_filter($results, static function ($value): bool {
            return $value !== [];
        }));

        $result = [];
        foreach ($matchingAccountIds as $id) {
            if (array_key_exists($id, $accounts)) {
                $result[$id] = $accounts[$id];
            }
        }

        return [count($accountIds), $result];
    }

    public function evaluateUser(int $accountId, int $apiKey, bool $preparedModels = false): void {
        if (!$preparedModels || !$this->rulesModel) {
            $this->buildEvaluationModels();
        }

        foreach ($this->totalModels as $model) {
            $model->updateTotalsByAccountIds([$accountId], $apiKey);
        }

        $operatorRules = $this->getAllRulesWithOperatorValues($this->rulesModel, $apiKey);
        $rules = array_intersect_key($this->rulesMap, $operatorRules);

        $result = $this->evaluateRules([$accountId], $rules, $apiKey);
        $uids = $result[$accountId];
        $details = [];

        foreach ($uids as $uid) {
            $details[] = ['uid' => $uid, 'score' => $operatorRules[$uid]['value']];
        }

        $data = [
            'score'     => $this->normalizeScore($details),
            'details'   => json_encode($details),
        ];

        $this->userController->updateUserStatus($accountId, $data, $apiKey);
    }

    public function buildEvaluationModels(?string $uid = null): void {
        $this->totalModels = [];
        foreach (\Utils\Constants::get('RULES_TOTALS_MODELS') as $className) {
            $this->totalModels[] = new $className();
        }

        $this->contextController    = new \Controllers\Admin\Context\Data();
        $this->userController       = new \Controllers\Admin\User\Data();
        $this->rulesModel           = new \Models\OperatorsRules();

        $rb = new \Ruler\RuleBuilder();

        if ($uid) {
            $ruleObj = \Utils\RulesClasses::getSingleRuleObject($uid, $rb);
            $this->rulesMap = $ruleObj ? [$uid => $ruleObj] : [];
        } else {
            $this->rulesMap = \Utils\RulesClasses::getAllRulesObjects($rb);
        }
    }

    private function normalizeScore(array $data): int {
        $scores = array_column($data, 'score');
        $totalScore = max(array_sum($scores), 0);

        $filterScores = array_filter($scores, function ($value) {
            return $value > 0;
        });

        $matches = count($filterScores);

        return max((int) (99 - ($totalScore * (pow($matches, 1.1) - $matches + 1))), 0);
    }

    // only valid, not missing, with fitting attributes, returning associative array
    private function getAllRulesWithOperatorValues(\Models\OperatorsRules $rulesModel, int $apiKey): array {
        $model = new \Models\ApiKeys();
        $skipAttributes = $model->getSkipEnrichingAttributes($apiKey);

        $rules = $rulesModel->getAllValidRulesByOperator($apiKey);

        $results = $this->filterRulesByAttributesAddTypes($rules, $skipAttributes);

        return $results;
    }

    // with fitting attributes and sorted, returning as regular array
    private function getAllAttrFilteredRulesByApiKey(int $apiKey): array {
        $model = new \Models\ApiKeys();
        $skipAttributes = $model->getSkipEnrichingAttributes($apiKey);

        $model = new \Models\OperatorsRules();
        $rules = $model->getAllRulesByOperator($apiKey);

        $results = $this->filterRulesByAttributesAddTypes($rules, $skipAttributes);

        usort($results, static function ($a, $b): int {
            if ($a['validated'] !== $b['validated']) {
                return ($b['validated'] <=> $a['validated']);
            }

            if ((int) ($a['missing'] === true) !== (int) ($b['missing'] === true)) {
                return ((int) $a['missing'] <=> (int) $b['missing']);
            }

            return $a['uid'] <=> $b['uid'];
        });

        return $results;
    }

    // do not filter by attributes if data is needed only for rendering info
    public function getAllRulesByApiKey(int $apiKey): array {
        $model = new \Models\OperatorsRules();
        $rules = $model->getAllRulesByOperator($apiKey);

        $results = [];
        foreach ($rules as $rule) {
            $rule['type'] = \Utils\RulesClasses::getRuleTypeByUid($rule['uid']);
            $results[] = $rule;
        }

        usort($results, static function ($a, $b): int {
            if ($a['validated'] !== $b['validated']) {
                return ($b['validated'] <=> $a['validated']);
            }

            if ((int) ($a['missing'] === true) !== (int) ($b['missing'] === true)) {
                return ((int) $a['missing'] <=> (int) $b['missing']);
            }

            return $a['uid'] <=> $b['uid'];
        });

        return $results;
    }

    private function filterRulesByAttributesAddTypes(array $rules, array $skipAttributes): array {
        $results = [];

        foreach ($rules as $id => $row) {
            if (!count(array_intersect(json_decode($row['attributes']), $skipAttributes))) {
                $row['type'] = \Utils\RulesClasses::getRuleTypeByUid($row['uid']);
                $results[$id] = $row;
            }
        }

        return $results;
    }
}