host-utils 1.0.2

use std::io;

use colored::Colorize;
use sha2::Digest;

use crate::db::UserData;

pub fn print_allow<R: io::Read, W: io::Write>(r: R, stdout: &mut W) -> io::Result<()> {
    let data = UserData::from_read(r)?;
    let mut list = Vec::with_capacity(data.allow.len());
    list.extend(data.allow.iter().map(|v| v.as_bytes()));
    list.sort();
    writeln!(stdout, "\t{}", "Allow List".yellow().bold().underline())?;
    for i in list {
        stdout.write_all(i)?;
        stdout.write_all(b"\n")?;
    }
    stdout.flush()
}
pub fn print_block<R: io::Read, W: io::Write>(r: R, stdout: &mut W) -> io::Result<()> {
    let data = UserData::from_read(r)?;
    let mut list = Vec::with_capacity(data.block.len());
    list.extend(data.block.iter().map(|v| v.as_bytes()));
    list.sort();
    writeln!(stdout, "\t{}", "Block List".yellow().bold().underline())?;
    for i in list {
        stdout.write_all(i)?;
        stdout.write_all(b"\n")?;
    }
    stdout.flush()
}
pub fn print_redirect<R: io::Read, W: io::Write>(r: R, stdout: &mut W) -> io::Result<()> {
    let data = UserData::from_read(r)?;
    let mut list = Vec::with_capacity(data.redirect.len());
    list.extend(
        data.redirect
            .iter()
            .map(|(k, v)| (v.as_bytes(), k.as_bytes())),
    );
    list.sort();
    writeln!(stdout, "\t{}", "Redirect List".yellow().bold().underline())?;
    for (to, from) in list {
        stdout.write_all(to)?;
        stdout.write_all(b"  ")?;
        stdout.write_all(from)?;
        stdout.write_all(b"\n")?;
    }
    stdout.flush()
}
pub fn print_sources<R: io::Read, W: io::Write>(r: R, stdout: &mut W) -> io::Result<()> {
    let data = UserData::from_read(r)?;
    let mut list = Vec::with_capacity(data.sources.len());
    list.extend(data.sources.keys().map(|k| k.as_bytes()));
    list.sort();
    writeln!(stdout, "\t{}", "Source List".yellow().bold().underline())?;
    for i in list {
        stdout.write_all(i)?;
        stdout.write_all(b"\n")?;
    }
    stdout.flush()
}

pub(crate) fn is_valid_host<T: AsRef<str>>(value: T) -> bool {
    let value = value.as_ref();
    if value.is_empty()
        || value.starts_with(' ')
        || value.ends_with(' ')
        || value.starts_with('.')
        || value.ends_with('.')
        || !value.contains('.')
    {
        return false;
    };
    for c in value.chars() {
        if c.is_ascii_uppercase()
            || c.is_ascii_lowercase()
            || c.is_ascii_digit()
            || (c == '.')
            || (c == '-')
            || (c == '_')
        {
            continue;
        } else {
            return false;
        }
    }
    true
}
pub(crate) fn get_host_from_url<'a, T: AsRef<str> + ?Sized>(webs: &'a T) -> Option<&'a str> {
    let url = webs.as_ref().trim_start();
    let f = |v: &'a str| {
        if let Some((host, _)) = v.split_once(['/', '?', '#', ':']) {
            if is_valid_host(host) {
                Some(host)
            } else {
                None
            }
        } else if is_valid_host(v) {
            Some(v)
        } else {
            None
        }
    };
    if url.starts_with("http") {
        url.split_once("://").and_then(|(left, right)| {
            if !matches!(left, "http" | "https") {
                None
            } else {
                f(right)
            }
        })
    } else {
        f(url)
    }
}

pub(crate) fn is_valid_url<T: AsRef<str>>(value: T) -> bool {
    value
        .as_ref()
        .split_once(r"://")
        .and_then(|(l, r)| {
            if !matches!(l, "http" | "https") {
                None
            } else {
                r.split_once('.')
            }
        })
        .and_then(|(l, r)| {
            if r.len() < 2
                || l.is_empty()
                || l.chars().any(|c| {
                    !matches!(&c,
                        'a'..='z' | 'A'..='Z' |
                        '0'..='9' | '_' | '-'
                    )
                })
            {
                return None;
            }
            if let Some((i, c)) = r.chars().enumerate().find(|(_, c)| {
                matches!(c, '/' | '?' | ':' | '#')
                    || !matches!(c,
                      'a'..='z' | 'A'..='Z' |
                      '0'..='9' | '.' | '_' | '-'
                    )
            }) {
                match (i, c) {
                    (_, 'a'..='z' | 'A'..='Z' | '0'..='9' | '.' | '_' | '-' | '/' | '?' | '#') => {
                        Some(())
                    }
                    (index, ':') => {
                        let mut port: u16 = 0;
                        let zero = '0' as u16;
                        for i in r.chars().skip(index + 1) {
                            match i {
                                '0'..='9' => {
                                    let v = i as u16 - zero;
                                    if let Some(v) = port.checked_mul(10) {
                                        port = v;
                                    } else {
                                        return None;
                                    }
                                    if let Some(u) = port.checked_add(v) {
                                        port = u;
                                    } else {
                                        return None;
                                    }
                                }
                                '/' | '?' | '#' => break,
                                _ => return None,
                            }
                        }
                        Some(())
                    }
                    _ => None,
                }
            } else {
                Some(())
            }
        })
        .is_some()
}

pub(crate) fn get_host_from_url_or_host(value: &str) -> Option<&str> {
    if is_comment(value) {
        return None;
    };
    let v: Vec<_> = value.split_whitespace().collect();
    if v.is_empty() {
        return None;
    };
    let u = if v.len() == 1 { v[0] } else { v[1] };
    if is_valid_host(u) {
        Some(u)
    } else if is_valid_url(u) {
        get_host_from_url(u)
    } else {
        None
    }
}

pub(crate) fn is_comment<T: AsRef<str>>(value: T) -> bool {
    let v = value.as_ref().trim_start();
    if v.is_empty() || v.starts_with('#') {
        return true;
    };
    false
}

pub(crate) fn sha256<T: AsRef<str>>(value: T) -> [u8; 32] {
    let mut hasher = sha2::Sha256::new();
    hasher.update(value.as_ref().as_bytes());
    hasher.finalize().into()
}

#[cfg(test)]
mod tests {}