<?php
/**
 * Design token graph. Framework-free on purpose: the Joomla component, the CLI
 * and any future automation all load tokens through this one class.
 */

namespace Fyoo\FigmaBridge;

defined('_FYOO_BRIDGE') || define('_FYOO_BRIDGE', 1);

class Tokens
{
    public const GROUPS = ['color', 'typography', 'spacing', 'radius', 'shadow', 'breakpoints'];

    public array $data;

    public function __construct(array $data)
    {
        $this->data = $data;
    }

    public static function fromJson(string $json): self
    {
        $data = json_decode($json, true);

        if (!is_array($data)) {
            throw new \InvalidArgumentException('Token payload is not valid JSON.');
        }

        return new self(self::validate($data));
    }

    public static function fromFile(string $path): self
    {
        if (!is_readable($path)) {
            throw new \InvalidArgumentException("Cannot read token file: $path");
        }

        return self::fromJson((string) file_get_contents($path));
    }

    /** Trust boundary: everything below arrives from a Figma plugin over the network. */
    public static function validate(array $data): array
    {
        foreach (['name', 'source', 'tokens'] as $key) {
            if (!isset($data[$key])) {
                throw new \InvalidArgumentException("Missing required key: $key");
            }
        }

        if (!is_array($data['tokens'])) {
            throw new \InvalidArgumentException('tokens must be an object.');
        }

        $clean = [
            'name'        => self::text($data['name'], 120),
            'source'      => in_array($data['source'], ['figma', 'manual', 'api'], true) ? $data['source'] : 'manual',
            'version'     => self::text($data['version'] ?? '0.1', 20),
            'generatedAt' => self::text($data['generatedAt'] ?? gmdate('c'), 40),
            'fileKey'     => self::text($data['fileKey'] ?? '', 64),
            'tokens'      => [],
            'components'  => [],
            'assets'      => [],
        ];

        foreach (self::GROUPS as $group) {
            $clean['tokens'][$group] = [];

            foreach ((array) ($data['tokens'][$group] ?? []) as $key => $value) {
                $key = self::key((string) $key);

                if ($key === '') {
                    continue;
                }

                $value = $group === 'typography' ? self::typography($value) : self::value($group, $value);

                if ($value !== null) {
                    $clean['tokens'][$group][$key] = $value;
                }
            }
        }

        foreach ((array) ($data['components'] ?? []) as $name => $def) {
            $clean['components'][self::text((string) $name, 120)] = [
                'role'      => self::key((string) ($def['role'] ?? '')),
                'target'    => self::key((string) ($def['target'] ?? '')),
                'overrides' => array_map([self::class, 'cssValue'], (array) ($def['overrides'] ?? [])),
            ];
        }

        foreach ((array) ($data['assets'] ?? []) as $asset) {
            if (!isset($asset['name'])) {
                continue;
            }

            $type = strtolower((string) ($asset['type'] ?? 'svg'));

            if (!in_array($type, ['svg', 'png', 'jpg'], true)) {
                continue;
            }

            $clean['assets'][] = [
                'name' => preg_replace('/[^A-Za-z0-9_.\-]/', '', (string) $asset['name']),
                'type' => $type,
                'data' => (string) ($asset['data'] ?? ''),
            ];
        }

        return $clean;
    }

    public function group(string $name): array
    {
        return $this->data['tokens'][$name] ?? [];
    }

    public function count(): int
    {
        return array_sum(array_map('count', $this->data['tokens']));
    }

    public function toJson(): string
    {
        return json_encode($this->data, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES);
    }

    private static function text(string $value, int $max): string
    {
        return substr(trim(strip_tags($value)), 0, $max);
    }

    private static function key(string $value): string
    {
        $value = strtolower(trim($value));
        $value = preg_replace('~[\s_/]+~', '-', $value);

        return trim(preg_replace('~[^a-z0-9.\-]~', '', (string) $value), '-');
    }

    /** Rejects anything that could escape the Less declaration it is written into. */
    public static function cssValue($value): ?string
    {
        if (is_numeric($value)) {
            return (string) $value;
        }

        if (!is_string($value)) {
            return null;
        }

        $value = trim($value);

        if ($value === '' || strlen($value) > 200 || preg_match('~[{};@\\\\]|/\*|url\s*\(|expression~i', $value)) {
            return null;
        }

        return $value;
    }

    private static function value(string $group, $value): ?string
    {
        $value = self::cssValue($value);

        if ($value === null) {
            return null;
        }

        if ($group === 'color' && !preg_match('~^(#[0-9a-f]{3,8}|rgba?\([\d\s.,%]+\)|hsla?\([\d\s.,%deg]+\))$~i', $value)) {
            return null;
        }

        return $value;
    }

    private static function typography($value): ?array
    {
        if (!is_array($value)) {
            return null;
        }

        $out = [];

        foreach (['fontFamily', 'fontSize', 'fontWeight', 'lineHeight', 'letterSpacing', 'textTransform'] as $prop) {
            if (isset($value[$prop])) {
                $clean = self::cssValue($value[$prop]);

                if ($clean !== null) {
                    $out[$prop] = $clean;
                }
            }
        }

        return $out ?: null;
    }
}