codefever/application/controllers/doc.php

<?php

require_once APPPATH . '/controllers/base.php';

class Doc extends Base
{
    public function __construct()
    {
        parent::__construct();
    }

    public function cn()
    {
        $this->_detail('zh-cn');
    }

    public function en()
    {
        $this->_detail('en-us');
    }

    private function _detail(string $docPath)
    {
        $path = $this->uri->uri_string;
        $segments = explode('/', $path);
        $fileName = $segments[count($segments) - 1];
        $rootDir = implode('/', [dirname(APPPATH), 'doc', $docPath]) . '/';
        $docDir = array_slice($segments, 2);
        $docFile = $rootDir . implode('/', $docDir);

        if (preg_match('/^\w{32}\.png$/', $fileName)) {
            $this->_assets($docFile);
            exit;
        }

        if (!file_exists($docFile)) {
            header("Location: /doc/{$segments[1]}");
            exit;
        }

        if (strpos($fileName, '.md')) {
            $docDir = array_slice($segments, 2, -1);
        }

        $menuFile = $rootDir . ($docDir ? implode('/', $docDir) : '') . '/index.md';

        $this->load->view('doc/detail', [
            'segments' => $segments,
            'menu' => str_replace('`', '\`', file_get_contents($menuFile)),
            'doc' => str_replace('`', '\`', file_get_contents($docFile)),
            'docName' => $this->_docName($rootDir),
        ]);
    }

    private function _docName(string $rootDir)
    {
        return function (string $path) use ($rootDir) {
            if (!$path) {
                return FALSE;
            }

            $docDir = substr($path, 8);
            $docDir = substr($docDir, 0, strrpos($docDir, '/'));
            $indexFile = $rootDir . $docDir . '/index.md';

            if (!file_exists($indexFile)) {
                return FALSE;
            }

            $path = str_replace(["/", "."], ["\\/", "\\."], $path);
            $data = file_get_contents($indexFile);

            preg_match("/\[(.+)\]\({$path}\)/i", $data, $matches);
            if (!$matches) {
                return FALSE;
            }

            return $matches[1];
        };
    }

    private function _assets($path)
    {
        if (!file_exists($path)) {
            exit;
        }

        $finfo = finfo_open(FILEINFO_MIME); // 返回 mime 类型
        $mimeType = finfo_file($finfo, $path);
        $contentType = explode(';', $mimeType)[0];
        finfo_close($finfo);

        header('Content-type: ' . $contentType);
        $file = fopen($path, 'r');
        echo fread($file, filesize($path));
        fclose($file);
    }
}