<?php
// MediaType.php
// Created: 2022-02-10
// Updated: 2023-02-01

namespace Index;

use InvalidArgumentException;
use Stringable;

class MediaType implements Stringable, IComparable, IEquatable {
    private string $category = '';
    private string $kind = '';
    private string $suffix = '';
    private array $params = [];

    public function __construct(string $category, string $kind, string $suffix, array $params) {
        $this->category = $category;
        $this->kind = $kind;
        $this->suffix = $suffix;
        $this->params = $params;
    }

    public function getCategory(): string {
        return $this->category;
    }

    public function getKind(): string {
        return $this->kind;
    }

    public function getSuffix(): string {
        return $this->suffix;
    }

    public function getParams(): array {
        return $this->params;
    }

    public function hasParam(string $name): bool {
        return isset($this->params[$name]);
    }

    public function getParam(string $name, int $filter = FILTER_DEFAULT, $options = null) {
        if(!isset($this->params[$name]))
            return null;
        return filter_var($this->params[$name], $filter, $options);
    }

    public function getCharset(): string {
        return $this->getParam('charset', FILTER_DEFAULT, FILTER_FLAG_STRIP_LOW | FILTER_FLAG_STRIP_HIGH) ?? 'utf-8';
    }

    public function getQuality(): float {
        return max(min(round($this->getParam('q', FILTER_SANITIZE_NUMBER_FLOAT, FILTER_FLAG_ALLOW_FRACTION) ?? 1, 2), 1), 0);
    }

    public function compareCategory(string $category): int {
        return ($this->category === '*' || $category === '*')
            ? 0 : strcmp($this->category, $category);
    }

    public function matchCategory(string $category): bool {
        return $this->category === '*' || $category === '*' || $this->category === $category;
    }

    public function compareKind(string $kind): int {
        return ($this->kind === '*' || $kind === '*')
            ? 0 : strcmp($this->kind, $kind);
    }

    public function matchKind(string $kind): bool {
        return $this->kind === '*' || $kind === '*' || $this->kind === $kind;
    }

    public function compareSuffix(string $suffix): int {
        return strcmp($this->suffix, $suffix);
    }

    public function matchSuffix(string $suffix): bool {
        return $this->suffix === $suffix;
    }

    public function compare(mixed $other): int {
        if(!($other instanceof MediaType)) {
            try {
                $other = self::parse((string)$other);
            } catch(InvalidArgumentException $ex) {
                return -1;
            }
        }

        if(($match = self::compareCategory($other->category)) !== 0)
            return $match;
        if(($match = self::compareKind($other->kind)) !== 0)
            return $match;

        return 0;
    }

    public function equals(mixed $other): bool {
        if(!($other instanceof MediaType)) {
            try {
                $other = self::parse((string)$other);
            } catch(InvalidArgumentException $ex) {
                return false;
            }
        }

        if(!$this->matchCategory($other->category))
            return false;
        if(!$this->matchKind($other->kind))
            return false;

        return true;
    }

    public function __toString(): string {
        $string = $this->category . '/' . $this->kind;

        if(!empty($this->suffix))
            $string .= '+' . $this->suffix;

        if(!empty($this->params))
            foreach($this->params as $key => $value) {
                $string .= ';';
                if(is_string($key))
                    $string .= $key . '=';
                $string .= $value;
            }

        return $string;
    }

    public static function parse(string $mediaTypeStr): MediaType {
        $parts = explode(';', $mediaTypeStr);
        if(empty($parts))
            throw new InvalidArgumentException('Invalid media type supplied.');

        $mediaTypeStr = array_shift($parts);
        $mediaTypeParts = explode('/', $mediaTypeStr, 2);

        $category = $mediaTypeParts[0];

        $kindSplit = explode('+', $mediaTypeParts[1] ?? '', 2);
        $kind = $kindSplit[0];
        $suffix = $kindSplit[1] ?? '';

        $params = [];

        foreach($parts as $part) {
            $paramSplit = explode('=', trim($part), 2);
            $params[trim($paramSplit[0])] = trim($paramSplit[1] ?? '', " \n\r\t\v\0\"");
        }

        return new MediaType($category, $kind, $suffix, $params);
    }

    public static function fromPath(string $path): MediaType {
        return self::parse(mime_content_type($path));
    }
}