map $http_accept $serve_markdown {
    default         0;
    ~*text/plain    1;
    ~*text/markdown 1;
}

map $request_uri $has_no_extension {
    ~^[^.]*$ 1;
    default  0;
}

# Nginx reverse proxy configuration for crawlee.dev
# Routes to GitHub Pages and handles legacy URL redirects
server {
    listen 0.0.0.0:8080;
    server_name 'crawlee.dev';

    # comment out the resolver and use localhost:3000 for local development
    set $backend "https://apify.github.io/crawlee";
    resolver 1.1.1.1 8.8.8.8 valid=30s ipv6=off;

    # Health check endpoint
    location /health {
        access_log off;
        return 200 '{"status":"UP"}';
        add_header Content-Type application/json;
    }

    location = / {
        if ($serve_markdown) {
            rewrite ^ /llms.txt last;
        }
        proxy_pass $backend/;
    }

    location ~ ^/(llms|llms-full)\.txt$ {
        proxy_hide_header Content-Type;
        add_header Content-Type 'text/markdown; charset=utf-8' always;
        proxy_pass $backend$uri;
    }

    # remove trailing slashes from all URLs (except root /)
    # exact match locations (e.g., location = /python/) take priority over this regex
    # Only match URIs composed of safe characters (letters, digits, dots, hyphens,
    # underscores, forward slashes). This prevents open redirect via %5C (backslash):
    # nginx decodes %5C to \ in $uri, and \ in the Location header gets normalized
    # to / by browsers, turning /\evil.com into //evil.com (protocol-relative URL).
    location ~ ^(/[a-zA-Z0-9][a-zA-Z0-9_./-]*)/$ {
        rewrite ^(.+)/$ $1$is_args$args? redirect;
    }

    location / {
        set $rewrite_condition "$serve_markdown$has_no_extension";
        set $proxy_path $request_uri;

        if ($rewrite_condition = "11") {
            set $proxy_path "${request_uri}.md";
        }
        proxy_pass $backend$proxy_path;
    }

    ### Repository path: "/python"

    location = /python {
        if ($serve_markdown) {
            rewrite ^ /python/llms.txt last;
        }
        proxy_pass https://apify.github.io/crawlee-python/;
    }

    location = /python/ {
        if ($serve_markdown) {
            rewrite ^ /python/llms.txt last;
        }
        proxy_pass https://apify.github.io/crawlee-python/;
    }

    location ~ ^/python/(llms|llms-full)\.txt$ {
        proxy_hide_header Content-Type;
        add_header Content-Type 'text/markdown; charset=utf-8' always;
        proxy_pass https://apify.github.io/crawlee-python/$1.txt;
    }

    location ~ ^/python/(.*)$ {
        set $path_suffix $1;
        set $proxy_path "/$path_suffix";
        set $rewrite_condition "$serve_markdown$has_no_extension";
        if ($rewrite_condition = "11") {
            set $proxy_path "${proxy_path}.md";
        }
        proxy_pass https://apify.github.io/crawlee-python$proxy_path;
    }

    # So that we can have both GH pages and crawlee.dev/python working and loading assets from the same path
    location /crawlee-python {
        proxy_pass https://apify.github.io/crawlee-python/;
    }

    # Redirect rule for old JS docs to go under /js prefix
    rewrite ^/docs(.*)$ /js/docs$1 permanent;
    rewrite ^/api(.*)$ /js/api$1 permanent;

    # Remove version numbers from /js/api/3.[0-9]/* and /js/docs/3.[0-9]/*
    rewrite ^/js/api/3\.\d(/.*)?$ /js/api$1 permanent;
    rewrite ^/js/docs/3\.\d(/.*)?$ /js/docs$1 permanent;

    # Redirect rule for "upgrading-to-v03" to "upgrading-to-v0x"
    rewrite ^/python/docs/upgrading/upgrading-to-v03$ /python/docs/upgrading/upgrading-to-v0x permanent;

    # Redirect rule so that /python/docs actually leads somewhere
    rewrite ^/python/docs/?$ /python/docs/quick-start;

    rewrite ^/versions/?$ /js/api/core/changelog permanent;
}