<?php

class SegmentRouter
{
	private array $routes = [];

	public function add(string $method, string $route, callable $handler)
	{
		// Expand the route into segments
		$segments = explode('/', trim($route, '/'));

		// Push each segment into the routes array as a node
		$node = &$this->routes;
		foreach ($segments as $segment) $node = &$node[$segment];

		// Add the handler to the last node
		$node[$method] = $handler;
	}

	public function lookup(string $method, string $uri): int
	{
		// Expand the URI into segments
		$uriSegments = explode('/', trim($uri, '/'));
		$node = $this->routes;
		$params = [];

		// Traverse the routes array to find the handler
		foreach ($uriSegments as $segment) {
			// Check if the segment exists in the node, or if there's a dynamic segment
			if (!isset($node[$segment])) {
				$dynamicSegment = $this->matchDynamicSegment($node, $segment);
				if ($dynamicSegment) {
					$params[] = $segment;
					$node = $node[$dynamicSegment];
				} else {
					return 404;
				}
			} else {
				$node = $node[$segment];
			}
		}

		// If the HTTP method is not supported, return 405
		if (!isset($node[$method])) return 405;

		// Call the handler
		$handler = $node[$method];
		call_user_func_array($handler, $params);
		return 200;
	}

	private function matchDynamicSegment(array $node, string $segment)
	{
		foreach ($node as $key => $value) {
			if (strpos($key, ':') === 0) return $key;
		}
		return null;
	}
}