<?php

namespace SoftminalCache\Framework\Support;

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

/**
 * A small PSR-3-flavoured logger that writes structured lines via error_log().
 *
 * Each channel gets a "[softminal_cache_{channel}] LEVEL message {context-json}" prefix so
 * entries are greppable. Debug lines are suppressed unless WP_DEBUG is on.
 *
 * PHP 7.4 compatible.
 */
class Logger
{
    const EMERGENCY = 'emergency';
    const ALERT     = 'alert';
    const CRITICAL  = 'critical';
    const ERROR     = 'error';
    const WARNING   = 'warning';
    const NOTICE    = 'notice';
    const INFO      = 'info';
    const DEBUG     = 'debug';

    /** Numeric severity for threshold comparisons (higher = more severe). */
    private static array $levels = [
        self::DEBUG     => 100,
        self::INFO      => 200,
        self::NOTICE    => 250,
        self::WARNING   => 300,
        self::ERROR     => 400,
        self::CRITICAL  => 500,
        self::ALERT     => 550,
        self::EMERGENCY => 600,
    ];

    private string $channel;

    public function __construct(string $channel = 'app')
    {
        $this->channel = $channel;
    }

    public static function channel(string $channel = 'app'): self
    {
        return new self($channel);
    }

    public function emergency(string $message, array $context = []): void
    {
        $this->log(self::EMERGENCY, $message, $context);
    }

    public function alert(string $message, array $context = []): void
    {
        $this->log(self::ALERT, $message, $context);
    }

    public function critical(string $message, array $context = []): void
    {
        $this->log(self::CRITICAL, $message, $context);
    }

    public function error(string $message, array $context = []): void
    {
        $this->log(self::ERROR, $message, $context);
    }

    public function warning(string $message, array $context = []): void
    {
        $this->log(self::WARNING, $message, $context);
    }

    public function notice(string $message, array $context = []): void
    {
        $this->log(self::NOTICE, $message, $context);
    }

    public function info(string $message, array $context = []): void
    {
        $this->log(self::INFO, $message, $context);
    }

    public function debug(string $message, array $context = []): void
    {
        $this->log(self::DEBUG, $message, $context);
    }

    /**
     * Log an exception with its class, message, and location.
     */
    public function exception(\Throwable $e, string $level = self::ERROR, array $context = []): void
    {
        $context = array_merge($context, [
            'exception' => get_class($e),
            'file'      => $e->getFile() . ':' . $e->getLine(),
        ]);
        $this->log($level, $e->getMessage(), $context);
    }

    public function log(string $level, string $message, array $context = []): void
    {
        if (!isset(self::$levels[$level])) {
            $level = self::INFO;
        }

        // Suppress debug noise unless explicitly debugging.
        if ($level === self::DEBUG && !(defined('WP_DEBUG') && WP_DEBUG)) {
            return;
        }

        $line = sprintf(
            '[softminal_cache_%s] %s %s',
            $this->channel,
            strtoupper($level),
            $this->interpolate($message, $context)
        );

        if (!empty($context)) {
            $encoded = function_exists('wp_json_encode') ? wp_json_encode($context) : json_encode($context);
            if ($encoded !== false) {
                $line .= ' ' . $encoded;
            }
        }

        // phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
        error_log($line);

        /**
         * Allow external log sinks (Sentry, files, etc.) to observe entries.
         */
        do_action('softminal_cache_log', $level, $message, $context, $this->channel);
    }

    /**
     * Replace {placeholders} in the message with scalar context values.
     */
    private function interpolate(string $message, array $context): string
    {
        if (strpos($message, '{') === false) {
            return $message;
        }

        $replacements = [];
        foreach ($context as $key => $value) {
            if (is_scalar($value) || $value === null || (is_object($value) && method_exists($value, '__toString'))) {
                $replacements['{' . $key . '}'] = (string) $value;
            }
        }

        return strtr($message, $replacements);
    }
}