<?php

class TrieRouter implements Router
{
	public array $root = [];

	// Add route to the trie
	public function add(string $method, string $route, callable $handler): Router
	{
		$node = &$this->root[$method];
		$segments = explode('/', trim($route, '/'));

		foreach ($segments as $segment) {
			if (!isset($node[$segment])) {
				$node[$segment] = ['_children' => [], '_handler' => null];
			}
			$node = &$node[$segment]['_children'];
		}

		$node['_handler'] = $handler;

		return $this;
	}

	// Find and handle the route
	public function lookup(string $method, string $uri): int|array
	{
		$node = &$this->root[$method];
		$segments = explode('/', trim($uri, '/'));
		$params = [];

		foreach ($segments as $segment) {
			if (isset($node[$segment])) {
				$node = &$node[$segment]['_children'];
			} else {
				// Handle dynamic parameters (e.g., :id)
				$dynamicSegment = $this->matchDynamicSegment($node, $segment);
				if ($dynamicSegment) {
					$params[] = $segment;
					$node = &$node[$dynamicSegment]['_children'];
				} else {
					return 404;
				}
			}
		}

		// Check if a handler exists for the current node
		if (isset($node['_handler'])) return [$node['_handler'], $params];

		return 404;
	}

	// Match dynamic route segments like ':id'
	private function matchDynamicSegment(array $node, string $segment)
	{
		foreach ($node as $key => $value) {
			if (strpos($key, ':') === 0) return $key;
		}
		return null;
	}

	public function clear(): Router
	{
		$this->root = [];
		return $this;
	}
}