<?php

if (!defined('ABSPATH')) {
    exit;
}

class AIEO_Semantic_Temporality {

    
    const MODE_OFF = 'off';
    
    const MODE_PREFER = 'prefer';
    
    const MODE_EXCLUDE = 'exclude';

    
    const DEFAULT_MONTHS = 6;

    
    private static function setting($key, $default) {
        return class_exists('AIEO_DMM_Settings')
            ? AIEO_DMM_Settings::get('semantic.' . $key, $default)
            : $default;
    }

    
    public static function mode() {
        $m = (string) self::setting('related_time_mode', self::MODE_OFF);
        return in_array($m, array(self::MODE_OFF, self::MODE_PREFER, self::MODE_EXCLUDE), true)
            ? $m
            : self::MODE_OFF;
    }

    
    public static function months() {
        $n = (int) self::setting('related_time_months', self::DEFAULT_MONTHS);
        return max(1, min(120, $n));
    }

    
    public static function post_types() {
        return self::sanitize_types(self::setting('related_time_post_types', array()));
    }

    
    public static function evergreen_types() {
        return self::sanitize_types(self::setting('related_time_evergreen_types', array()));
    }

    
    private static function sanitize_types($types) {
        $out = array();
        foreach ((array) $types as $t) {
            $t = sanitize_key((string) $t);
            if ('' !== $t && !in_array($t, $out, true)) {
                $out[] = $t;
            }
        }
        return $out;
    }

    
    public static function applies_to($source_type) {
        if (self::MODE_OFF === self::mode()) {
            return false;
        }
        $source_type = (string) $source_type;
        if (in_array($source_type, self::evergreen_types(), true)) {
            return false; 
        }
        return in_array($source_type, self::post_types(), true);
    }

    
    private static function dates(array $ids) {
        static $memo = array();
        $ids  = array_values(array_unique(array_filter(array_map('intval', $ids))));
        $out  = array();
        $ask  = array();
        foreach ($ids as $id) {
            if (array_key_exists($id, $memo)) {
                if (null !== $memo[$id]) {
                    $out[$id] = $memo[$id];
                }
            } else {
                $ask[] = $id;
            }
        }
        if (empty($ask)) {
            return $out;
        }
        global $wpdb;
        foreach (array_chunk($ask, 400) as $chunk) {
            $ph = implode(',', array_fill(0, count($chunk), '%d'));
            
            $rows = $wpdb->get_results($wpdb->prepare(
                "SELECT ID, post_date_gmt FROM {$wpdb->posts} WHERE ID IN ({$ph})",
                $chunk
            ), ARRAY_A);
            foreach ((array) $rows as $r) {
                $id = (int) $r['ID'];
                $ts = strtotime((string) $r['post_date_gmt'] . ' UTC');
                
                
                $memo[$id] = ($ts && $ts > 0) ? $ts : null;
                if (null !== $memo[$id]) {
                    $out[$id] = $memo[$id];
                }
            }
        }
        foreach ($ask as $id) {
            if (!array_key_exists($id, $memo)) {
                $memo[$id] = null;
            }
        }
        return $out;
    }

    
    public static function partition($source_type, $source_id, array $targets) {
        $inside  = array();
        $outside = array();
        if (!self::applies_to($source_type)) {
            foreach ($targets as $t) {
                $inside[] = (int) $t[0];
            }
            return array('inside' => $inside, 'outside' => $outside);
        }

        $evergreen = self::evergreen_types();
        $ids       = array((int) $source_id);
        foreach ($targets as $t) {
            $ids[] = (int) $t[0];
        }
        $dates  = self::dates($ids);
        $anchor = isset($dates[(int) $source_id]) ? $dates[(int) $source_id] : 0;
        $span   = self::months() * 30.44 * DAY_IN_SECONDS;

        foreach ($targets as $t) {
            $tid  = (int) $t[0];
            $type = isset($t[1]) ? (string) $t[1] : '';
            if (in_array($type, $evergreen, true) || $anchor <= 0 || empty($dates[$tid])) {
                $inside[] = $tid;
                continue;
            }
            if (abs($dates[$tid] - $anchor) <= $span) {
                $inside[] = $tid;
            } else {
                $outside[] = $tid;
            }
        }
        return array('inside' => $inside, 'outside' => $outside);
    }
}