pukram-server/src/main.rs

use std::{
    collections::{hash_map::Entry, HashMap},
    env,
    fs::File,
    io::{prelude::*, BufReader, Error, ErrorKind, Result},
    net::{TcpListener, TcpStream},
};

use data_stream::{
    collections::SizeSettings, default_settings::PortableSettings, from_stream, to_stream,
    FromStream, ToStream,
};
use maud::html;
use percent_encoding::percent_decode_str;
use pukram2html::{convert, convert_extended, convert_subheader, Settings};

mod request;
use request::Request;

fn main() {
    let mut context = Context::default();
    let mut args = env::args();
    args.next();
    let address = args.next().unwrap_or("127.0.0.1:8080".to_string());
    let listener = TcpListener::bind(address).expect("Invalid bind address!");
    eprintln!("Strated server!");

    for stream in listener.incoming() {
        eprintln!("New connection!");

        let Ok(stream) = stream else {
            eprintln!("Connection failed!");
            continue;
        };

        context.handle_connection(stream);
    }
}

fn fail(mut stream: TcpStream) {
    let _ = write!(stream, "HTTP/1.1 404 Not Found\r\n\r\n");
    let _ = writeln!(stream, "Page not found!");
}

struct Comment {
    name: Box<str>,
    text: Box<str>,
}

#[derive(Default)]
struct SiteInfo {
    comments: Vec<Comment>,
    visits: usize,
    up: usize,
    down: usize,
}

impl<S: SizeSettings> ToStream<S> for SiteInfo {
    fn to_stream<W: Write>(&self, stream: &mut W) -> Result<()> {
        S::size_to_stream(self.comments.len(), stream)?;
        for Comment { name, text } in &self.comments {
            let name_bytes = name.as_bytes();
            S::size_to_stream(name_bytes.len(), stream)?;
            stream.write_all(name_bytes)?;

            let text_bytes = text.as_bytes();
            S::size_to_stream(text_bytes.len(), stream)?;
            stream.write_all(text_bytes)?;
        }

        S::size_to_stream(self.visits, stream)?;
        S::size_to_stream(self.up, stream)?;
        S::size_to_stream(self.down, stream)?;

        Ok(())
    }
}

impl<S: SizeSettings> FromStream<S> for SiteInfo {
    fn from_stream<R: Read>(stream: &mut R) -> Result<Self> {
        let size = S::size_from_stream(stream)?;
        let comments = (0..size)
            .map(|_| {
                let name_bytes = <Vec<_> as FromStream<S>>::from_stream(stream)?;
                let name = std::str::from_utf8(&name_bytes)
                    .map_err(|e| Error::new(ErrorKind::InvalidData, e))?
                    .into();

                let text_bytes = <Vec<_> as FromStream<S>>::from_stream(stream)?;
                let text = std::str::from_utf8(&text_bytes)
                    .map_err(|e| Error::new(ErrorKind::InvalidData, e))?
                    .into();

                Ok(Comment { name, text })
            })
            .collect::<Result<Vec<_>>>()?;

        let visits = S::size_from_stream(stream)?;
        let up = S::size_from_stream(stream)?;
        let down = S::size_from_stream(stream)?;

        Ok(SiteInfo {
            comments,
            visits,
            up,
            down,
        })
    }
}

#[derive(Default)]
struct Context {
    infos: HashMap<Box<str>, SiteInfo>,
}

impl Context {
    fn handle_connection(&mut self, mut stream: TcpStream) {
        let Some(request) = Request::from(&stream) else {
            eprintln!("Invalid request!");
            return;
        };

        eprintln!();
        eprintln!("Request:");
        eprintln!("- Method: {}", request.method);
        eprintln!("- Path: {}", request.path);
        eprintln!("- Version: {}", request.version);
        eprintln!("- Headers:");
        for header in request.headers {
            eprintln!("  - {header}");
        }
        eprintln!("- Body: {}", request.body);
        eprintln!();

        let Ok(current_dir) = env::current_dir() else {
            fail(stream);
            return;
        };

        let mut path = current_dir;

        let (relative_path, _) = request
            .path
            .split_once('?')
            .unwrap_or((&request.path, Default::default()));

        if relative_path.contains("//") {
            fail(stream);
            return;
        }

        let relative_path = if relative_path.is_empty() {
            String::new()
        } else {
            let path = percent_decode_str(&relative_path[1..]).decode_utf8_lossy();
            if path.contains('_') {
                let path = path.replace('_', " ");
                let _ = write!(stream, "HTTP/1.1 308 Permanent Redirect\r\n");
                let _ = write!(stream, "Location: /{path}\r\n\r\n");
                return;
            }
            path.to_string()
        };

        let (pk_file, pki_file, data_path, start_level) = if !relative_path.is_empty() {
            path.push(&relative_path);
            let (pk_extension, pki_extension, data_extension) =
                if let Some(extension) = path.extension() {
                    (
                        format!("{extension:?}.pk"),
                        format!("{extension:?}.pki"),
                        format!("{extension:?}.dat"),
                    )
                } else {
                    ("pk".to_string(), "pki".to_string(), "dat".to_string())
                };
            let pk_path = path.with_extension(pk_extension);
            let pki_path = path.with_extension(pki_extension);
            let data_path = path.with_extension(data_extension);

            let (Ok(pk_file), Ok(pki_file)) = (File::open(pk_path), File::open(pki_path)) else {
                fail(stream);
                return;
            };

            (pk_file, Some(pki_file), data_path, 1)
        } else {
            let mut pk_path = path.clone();
            pk_path.push("index.pk");
            let mut data_path = path.clone();
            data_path.push("index.dat");

            let Ok(pk_file) = File::open(pk_path) else {
                fail(stream);
                return;
            };

            (pk_file, None, data_path, 0)
        };

        use Entry::*;
        let info = match self.infos.entry(relative_path.clone().into_boxed_str()) {
            Occupied(o) => o.into_mut(),
            Vacant(v) => v.insert(
                File::open(&data_path)
                    .map(|mut file| {
                        from_stream::<PortableSettings, _, _>(&mut file).unwrap_or_default()
                    })
                    .unwrap_or_default(),
            ),
        };

        let mut name = None;
        let mut text = None;

        for entry in request.body.split('&') {
            let Some((key, input)) = entry.split_once('=') else {
                continue;
            };

            match key {
                "name" => {
                    let name_value = input.replace('+', " ");
                    let decoded_name = percent_decode_str(&name_value).decode_utf8_lossy();
                    eprintln!("Received comment by \"{decoded_name}\":");
                    name = Some(
                        decoded_name
                            .replace('&', "&amp;")
                            .replace('<', "&lt;")
                            .replace('>', "&gt;")
                            .into(),
                    );
                }
                "text" => {
                    let text_value = input.replace('+', " ");
                    let decoded_text = percent_decode_str(&text_value).decode_utf8_lossy();
                    for line in decoded_text.lines() {
                        eprintln!("  {line}");
                    }
                    eprintln!();
                    let mut text_buf = Vec::new();
                    convert(decoded_text.lines(), &mut text_buf);
                    text = Some(
                        std::str::from_utf8(text_buf.as_slice())
                            .unwrap_or_default()
                            .into(),
                    );
                }
                "up" => info.up += 1,
                "down" => info.down += 1,
                _ => (),
            }
        }

        if let (Some(name), Some(text)) = (name, text) {
            info.comments.push(Comment { name, text });
        }

        info.visits += 1;

        if let Ok(mut file) = File::create(data_path) {
            if to_stream::<PortableSettings, _, _>(info, &mut file).is_err() {
                eprintln!("Error saving data!");
                eprintln!();
            }
        }

        let _ = write!(stream, "HTTP/1.1 200 OK\r\n\r\n");

        let _ = writeln!(stream, "<meta charset=\"utf-8\">");

        let _ = writeln!(
            stream,
            "<p>👁️{} 💖️{} 💔️{}</p>",
            info.visits, info.up, info.down
        );

        let title = relative_path
            .rsplit_once('/')
            .map(|(_, title)| title)
            .unwrap_or(&relative_path);
        if !title.is_empty() {
            let _ = writeln!(stream, "<h1>{title}</h1>");
        }

        let path_ref = &path;

        let handle_entry = |entry: &str, output: &mut TcpStream, level: usize| {
            let level = level + 1;
            let mut path = path_ref.clone();
            let entry = if let Some((entry, _)) = entry.split_once(':') {
                entry
            } else {
                entry
            };
            path.push(entry);
            let extension = if let Some(extension) = path.extension() {
                format!("{extension:?}.pki")
            } else {
                "pki".to_string()
            };
            path.set_extension(extension);
            let Ok(file) = File::open(path) else {
                return;
            };
            let _ = writeln!(
                output,
                "<h{level}><a href=\"{relative_path}/{entry}\">{entry}</a></h{level}>"
            );
            convert_subheader(
                BufReader::new(file)
                    .lines()
                    .map(|line| line.unwrap_or_default()),
                output,
                level,
            );
        };

        convert_extended(
            BufReader::new(pk_file)
                .lines()
                .map(|line| line.unwrap_or_default()),
            &mut stream,
            Settings::default()
                .with_handler(handle_entry)
                .with_start_level(start_level)
                .with_use_textboxes(true),
        );

        let parent_path = relative_path
            .rsplit_once('/')
            .map(|(path, _)| path)
            .unwrap_or_default();

        let _ = writeln!(stream, "<hr>");
        let _ = writeln!(stream, "<a href=\"/{parent_path}\">&lt;&lt; Back</a>");

        if let Some(pki_file) = pki_file {
            let _ = writeln!(stream, "<h1>Description</h1>");

            convert_subheader(
                BufReader::new(pki_file)
                    .lines()
                    .map(|line| line.unwrap_or_default()),
                &mut stream,
                1,
            );

            let _ = writeln!(stream, "<hr>");
            let _ = writeln!(stream, "<a href=\"/{parent_path}\">&lt;&lt; Back</a>");
        }

        let html = html! {
            h1 { "Comments" }
            form method="POST" {
                input type="text" name="name" value="anon" placeholder="Name";
                br;
                textarea rows="5" cols="60" name="text" placeholder="Enter comment..." {}
                br;
                input type="submit" value="Send!";
            }
            form method="POST" {
                input type="submit" value="💖️" name="up";
                input type="submit" value="💔️" name="down";
            }
        };
        let _ = stream.write_all(html.into_string().as_bytes());

        for Comment { name, text } in &info.comments {
            let _ = writeln!(stream, "<fieldset><legend>{name}</legend>{text}</fieldset>");
        }

        let _ = writeln!(stream, "<hr>");
        let _ = writeln!(stream, "<a href=\"/{parent_path}\">&lt;&lt; Back</a>");
    }
}