<?php

namespace SmartDataContext\Domain;

class SmartDataContext {
    static function ValidateContent($content) {
        if (! $content) {
            return ["content property empty"];
        } else {
            return [];
        }
    }

    static function ValidateFeatures($features) {
        if ($features && array_key_exists("tags", $features) && is_array($features["tags"])) {
            return [];
        } else {
            return ["features missing tags entry or invalid (should be an array)"];
        }
    }

    static function ValidateTimestamp($t0, $t1) {
        if (! is_int($t0) || ! is_int($t1)) {
            return ["t0 and t1 must time integer timestamps"];
        } else if ($t0 > $t1 && $t1 != -1) {
            return ["t1 must be equal or after t0"];
        } else {
            return [];
        }
    }

    static function ValidateSmartDataSources(mixed $smartDataSources) {
        if (! is_array($smartDataSources)) {
            return ["smartDataSources should be an array"];
        }
        $result = [];
        foreach ($smartDataSources as $smartDataSource) {
            if (is_string($smartDataSource)) {
                // TODO: Support confidence
                if (! SmartDataContext::ValidSignature($smartDataSource)) {
                    $result[] = "$smartDataSource is an invalid signature";
                }
            } else if (is_array($smartDataSource)) {
                if (! SmartDataContext::ValidSphere($smartDataSource)) {
                    $result[] = json_encode($smartDataSource) . " is an invalid sphere";
                }
            }
        }
        return $result;
    }

    static function ValidSignature(string $signature) {
        return preg_match('/^[a-f0-9]+$/i', $signature);
    }

    static function ValidSphere(array $sphere) {
        // TODO: Support confidence
        return count(array_filter($sphere, 'is_int')) == 4;
    }

    static function ValidateSmartDataUnits(mixed $smartDataUnits) {
        if (is_array($smartDataUnits) && count(array_filter($smartDataUnits, 'is_int')) == count($smartDataUnits)) {
            return [];
        } else {
            return ["smartDataUnits should be a array of longs"];
        }
    }

}