//
// lib.rs
// Copyright (C) 2023 Óscar García Amor <[email protected]>
// Distributed under terms of the GNU GPLv3 license.
//

#[macro_use]
extern crate rocket;

use std::fs::{
    copy, create_dir, create_dir_all, read_to_string, remove_dir_all, remove_file, rename, write,
    File,
};
use std::io::{self, Error, ErrorKind, Read};
use std::path::{Path, PathBuf};

use rand::seq::SliceRandom;
use rocket::data::Capped;
use rocket::fs::TempFile;
use rocket::http::uri::Host;
use rocket::serde::json;
use syntect::easy::HighlightLines;
use syntect::highlighting::{Color, Style, ThemeSet};
use syntect::html::{styled_line_to_highlighted_html, IncludeBackground};
use syntect::parsing::SyntaxSet;
use syntect::util::{as_24_bit_terminal_escaped, LinesWithEndings};
use rocket::tokio::fs::File as TokioFile;
use time::{Duration, OffsetDateTime};

pub mod models;
use crate::models::LesmaMeta;

/// Defines clients requesting information in plain text.
pub const PLAIN_TEXT_AGENTS: [&'static str; 5] =
    ["curl", "httpie", "lwp-request", "wget", "python-requests"];

/// Simple struct to store an incremental hasher for BLAKE3.
struct B3Hasher(blake3::Hasher);

impl B3Hasher {
    /// Add input to the hash.
    fn update(&mut self, input: &[u8]) {
        self.0.update(input);
    }
    /// Finalize the state and return a hash string.
    fn finalize(&mut self) -> String {
        self.0.finalize().to_hex().to_string()
    }
}

/// Calculates BLAKE3 hash of a file
fn hasher<R: Read>(mut reader: R, state: &mut B3Hasher) -> io::Result<()> {
    let mut buf = [0; 32768];
    loop {
        match reader.read(&mut buf) {
            Ok(0) => return Ok(()),
            Ok(n) => state.update(&buf[..n]),
            Err(e) => return Err(e)
        }
    }
}

/// Struct for read binary file with its name
pub struct BinaryFile(pub PathBuf, pub TokioFile, pub String);

impl BinaryFile {
    pub async fn open<P: AsRef<Path>>(path: P, name: String) -> io::Result<BinaryFile> {
        let file = TokioFile::open(path.as_ref()).await?;
        Ok(BinaryFile(path.as_ref().to_path_buf(), file, name))
    }
}

/// Struct for lesma manager
pub struct Lesma {
    pub id: String,
    pub hash: String,
    pub storage: PathBuf,
}

/// lesma manager implementation
///
/// # Example
///
/// ```
/// use lesma::Lesma;
///
/// // To create a new lesma with random ID and hash
/// let lesma = Lesma::new(std::env::temp_dir());
///
/// // To create a new lesma from a given ID
/// let lesma = Lesma::from(std::env::temp_dir(), "lesma");
/// ```
impl Lesma {
    /// Returns new lesma manager
    ///
    /// # Example
    ///
    /// ```
    /// use lesma::Lesma;
    ///
    /// let temp_dir = std::env::temp_dir();
    /// let lesma = Lesma::new(temp_dir);
    /// assert!(lesma.id.len() >= 4);
    /// assert_eq!(64, lesma.hash.len());
    /// ```
    pub fn new(storage: PathBuf) -> Lesma {
        // Get new ID and hash
        let (id, hash) = new_hash(&storage);
        Lesma {
            id,
            hash,
            storage
        }
    }

    /// Returns new lesma manager from given ID
    ///
    /// # Example
    ///
    /// ```
    /// use lesma::Lesma;
    ///
    /// let temp_dir = std::env::temp_dir();
    /// let id = "lesma";
    /// let hash = "d887e6b1413f5dc4892bb390438e033eaf5dab94f9064eee73f7ba64f702f1ec";
    /// let lesma = Lesma::from(temp_dir, id);
    /// assert_eq!(id.to_string(), lesma.id);
    /// assert_eq!(hash.to_string(), lesma.hash);
    /// ```
    pub fn from<S: Into<String>>(storage: PathBuf, id: S) -> Lesma {
        let id = id.into();
        let hash = blake3::hash(id.as_bytes()).to_hex().to_string();
        Lesma {
            id,
            hash,
            storage
        }
    }

    /// Returns new lesma manager from given ID and hash
    ///
    /// # Example
    ///
    /// ```
    /// use lesma::Lesma;
    ///
    /// let temp_dir = std::env::temp_dir();
    /// let id = "lesma";
    /// let hash = "d887e6b1413f5dc4892bb390438e033eaf5dab94f9064eee73f7ba64f702f1ec";
    /// let lesma = Lesma::from_id_hash(temp_dir, id, hash);
    /// assert_eq!(id.to_string(), lesma.id);
    /// assert_eq!(hash.to_string(), lesma.hash);
    /// ```
    pub fn from_id_hash<S: Into<String>>(storage: PathBuf, id: S, hash: S) -> Lesma {
        let id = id.into();
        let hash = hash.into();
        Lesma {
            id,
            hash,
            storage
        }
    }

    /// Saves a binary data lesma
    pub async fn save_data(&self, temp: &PathBuf, limit: u8, expire: u32, password: Option<String>, data: &mut Capped<TempFile<'_>>) -> Result<(), Error> {
        // Get the raw name of the uploaded file (safe to unwrap since it has checked before)
        let raw_name = data.raw_name().unwrap().dangerous_unsafe_unsanitized_raw().as_str();
        let file_path_buf = PathBuf::from(raw_name);
        // Get sanitized file name
        let file_name = file_path_buf.file_name().ok_or(Error::new(ErrorKind::InvalidData, "Invalid filename"))?.to_str().unwrap();
        // A temporary file is needed to store the data received in the request, the new_hash function
        // can be used for this purpose
        let (_, temp_file_name) = new_hash(&temp);
        let temp_file = temp.join(&temp_file_name);
        if data.is_complete() {
            // Data are persisted to the temporary file
            data.persist_to(&temp_file).await?;
        } else {
            // The file is larger than allowed in the configuration
            return Err(Error::new(ErrorKind::BrokenPipe, "File too large"))
        }
        // Calculate BLAKE3 hash of file
        let mut file = File::open(&temp_file)?;
        let mut b3hasher = B3Hasher(blake3::Hasher::new());
        hasher(&mut file, &mut b3hasher)?;
        let lesma_hash = b3hasher.finalize();
        // Get data directory and counter, data and meta files
        let data_dir = self.storage.join("data").join(&lesma_hash);
        let counter_file = data_dir.join("_counter");
        let data_file = data_dir.join("_data");
        let meta_file = self.storage.join("meta").join(&self.hash);
        // Fill in the metadata
        let lesma_meta = LesmaMeta {
            hash: lesma_hash,
            password: password.map(|p| blake3::hash(p.as_bytes()).to_hex().to_string()),
            name: file_name.to_string(),
            binary: true,
            limit: limit,
            current: 0,
            create: OffsetDateTime::now_utc(),
            expire: OffsetDateTime::now_utc() + Duration::hours(expire.into())
        };
        // Serialize metadata in JSON
        let meta_json = json::to_string(&lesma_meta)?;
        // Stores the metadata in the metadata file
        write(meta_file, meta_json)?;
        // Check if the data already exists
        if data_dir.is_dir() {
            // Add +1 to counter file
            let mut counter = read_to_string(&counter_file)?.trim().parse::<u32>().map_err(|e| Error::new(ErrorKind::InvalidData, e))?;
            counter += 1;
            write(counter_file, counter.to_string())?;
        } else {
            // Create new data directory
            create_dir(&data_dir)?;
            // Try to move the file from the temporary location to the final location if this is not
            // possible copy it.
            rename(&temp_file, &data_file).or_else(|_| {
                copy(&temp_file, data_file)?;
                remove_file(temp_file)
            })?;
            write(counter_file, "1")?;
        }
        Ok(())
    }

    /// Saves a plain text lesma
    pub fn save_plain(&self, limit: u8, expire: u32, password: Option<String>, lesma: &String) -> Result<(), Error> {
        // Calculate BLAKE3 hash of lesma
        let lesma_hash = blake3::hash(lesma.as_bytes()).to_hex().to_string();
        // Get data directory and counter, data and meta files
        let data_dir = self.storage.join("data").join(&lesma_hash);
        let counter_file = data_dir.join("_counter");
        let data_file = data_dir.join("_data");
        let meta_file = self.storage.join("meta").join(&self.hash);
        // Fill in the metadata
        let lesma_meta = LesmaMeta {
            hash: lesma_hash,
            password: password.map_or(None, |p| if p == "".to_string() {
                None
            } else {
                Some(blake3::hash(p.as_bytes()).to_hex().to_string())
            }),
            name: "lesma".to_string(),
            binary: false,
            limit: limit,
            current: 0,
            create: OffsetDateTime::now_utc(),
            expire: OffsetDateTime::now_utc() + Duration::hours(expire.into())
        };
        // Serialize metadata in JSON
        let meta_json = json::to_string(&lesma_meta)?;
        // Stores the metadata in the metadata file
        write(meta_file, meta_json)?;
        // Check if the data already exists
        if data_dir.is_dir() {
            // Add +1 to counter file
            let mut counter = read_to_string(&counter_file)?.trim().parse::<u32>().map_err(|e| Error::new(ErrorKind::InvalidData, e))?;
            counter += 1;
            write(counter_file, counter.to_string())?;
        } else {
            // Create new data directory
            create_dir(&data_dir)?;
            // Save data
            write(data_file, lesma)?;
            write(counter_file, "1")?;
        }
        Ok(())
    }

    /// Reads lesma metadata
    pub fn read_meta(&self) -> Result<LesmaMeta, Error> {
        // Get metadata file
        let meta_file = self.storage.join("meta").join(&self.hash);
        // Read file and deserialize JSON metadata
        let meta_json = read_to_string(&meta_file)?;
        let lesma_meta = json::from_str::<LesmaMeta>(&meta_json).map_err(|e| Error::new(ErrorKind::InvalidData, e))?;
        Ok(lesma_meta)
    }

    /// Reads plain lesma data
    pub fn read_plain_data(&self, lesma_meta: &LesmaMeta, password: Option<String>) -> Result<String, Error> {
        // Check if lesma has expired or if has reached max views
        if lesma_has_expired(&lesma_meta) || lesma_reached_max_views(&lesma_meta) {
            trace!("Deleting expired plain lesma: {} / {}", self.id, self.hash);
            self.delete(&lesma_meta)?;
            debug!("Deleted expired plain lesma: {} / {}", self.id, self.hash);
            return Err(Error::new(ErrorKind::InvalidData, "lesma expired"))
        }
        // Check for password
        if lesma_meta.password.is_none() || lesma_meta.password == password.map(|p| blake3::hash(p.as_bytes()).to_hex().to_string()) {
            // Updates metadata
            trace!("Updating plain lesma metadata: {} / {}", self.id, self.hash);
            self.update_meta(&lesma_meta)?;
            debug!("Updated plain lesma metadata: {} / {}", self.id, self.hash);
            // Get and read data file
            let data_file = self.storage.join("data").join(&lesma_meta.hash).join("_data");
            read_to_string(&data_file)
        } else {
            trace!("lesma is password protected and the user has not entered the magic word");
            return Err(Error::new(ErrorKind::InvalidData, "invalid password"))
        }
    }

    /// Reads binary lesma data
    pub async fn read_binary_data(&self, lesma_meta: &LesmaMeta, password: Option<String>) -> io::Result<BinaryFile> {
        // Check if lesma has expired or if has reached max views
        if lesma_has_expired(&lesma_meta) || lesma_reached_max_views(&lesma_meta) {
            trace!("Deleting expired binary lesma: {} / {}", self.id, self.hash);
            self.delete(&lesma_meta)?;
            debug!("Deleted expired binary lesma: {} / {}", self.id, self.hash);
            return Err(Error::new(ErrorKind::InvalidData, "lesma expired"))
        }
        // Check for password
        if lesma_meta.password.is_none() || lesma_meta.password == password.map(|p| blake3::hash(p.as_bytes()).to_hex().to_string()) {
            // Updates metadata
            trace!("Updating binary lesma metadata: {} / {}", self.id, self.hash);
            self.update_meta(&lesma_meta)?;
            debug!("Updated binary lesma metadata: {} / {}", self.id, self.hash);
            // Get and read data file
            let data_file = self.storage.join("data").join(&lesma_meta.hash).join("_data");
            if ! data_file.is_file() {
                error!("Binary lesma {} retains metafile but its data has vanished (HASH: {})", &self.id, &self.hash);
            }
            BinaryFile::open(data_file, lesma_meta.name.clone()).await
        } else {
            trace!("lesma is password protected and the user has not entered the magic word");
            return Err(Error::new(ErrorKind::InvalidData, "invalid password"))
        }
    }

    /// Updates lesma metadata
    pub fn update_meta(&self, lesma_meta: &LesmaMeta) -> Result<(), Error> {
        // Only if it has a download limit
        if lesma_meta.limit > 0 {
            // Make lesma meta struct mutable
            let mut mut_lesma_meta = lesma_meta.clone();
            // Update download counter
            mut_lesma_meta.current += 1;
            // Serialize metadata in JSON
            let meta_json = json::to_string(&mut_lesma_meta)?;
            // Get and metadata file
            let meta_file = self.storage.join("meta").join(&self.hash);
            // Stores the metadata in the metadata file
            debug!("Updating the download counter from {} to {}", lesma_meta.current, mut_lesma_meta.current);
            write(meta_file, meta_json)
        } else {
            trace!("No download limit, no counter update is required");
            Ok(())
        }
    }

    /// Deletes an existing lesma
    pub fn delete(&self, lesma_meta: &LesmaMeta) -> Result<(), Error> {
        // Get data directory and counter and meta files
        let data_dir = self.storage.join("data").join(&lesma_meta.hash);
        let counter_file = data_dir.join("_counter");
        let meta_file = self.storage.join("meta").join(&self.hash);
        // Reads counter file
        let mut counter = read_to_string(&counter_file)?.trim().parse::<u32>().map_err(|e| Error::new(ErrorKind::InvalidData, e))?;
        if counter > 1 {
            // Removes -1 to counter
            counter -= 1;
            write(counter_file, counter.to_string())?;
            trace!("Counter updated to: {}", counter);
        } else {
            // Removes lesma data directory
            debug!("Deleting data directory: {}", &lesma_meta.hash);
            remove_dir_all(data_dir)?;
            trace!("Data directory deleted: {}", &lesma_meta.hash);
        }
        // Removes lesma meta file
        debug!("Deleting metafile: {}", &self.hash);
        remove_file(meta_file)
    }
}

/// Returns a pseudo ramdom string with pattern consonant-vowel.
///
/// # Example
///
/// ```
/// use lesma::new_id;
///
/// // Generate new ID string with four consonants and four vowels
/// let nid = new_id(4);
/// assert_eq!(8, nid.len());
/// ```
pub fn new_id(length: u8) -> String {
    let consonants: Vec<char> = "bcdfghjklmnpqrstvwxyz".chars().collect();
    let vowels: Vec<char> = "aeiou".chars().collect();
    let mut id = String::new();
    let mut rng = rand::thread_rng();
    for _ in 0..length {
        id.push(*consonants.choose(&mut rng).unwrap());
        id.push(*vowels.choose(&mut rng).unwrap());
    }
    debug!("New ID generated: {}", &id);
    id
}

/// Returns a tuple with a pseudo ramdom string with pattern consonant-vowel and its BLAKE3 hash.
///
/// # Example
///
/// ```
/// use lesma::new_hash;
///
/// // Directory where it checks that the new ID has not already been generated
/// let temp_dir = std::env::temp_dir();
///
/// // Generate new ID string and its BLAKE3 hash
/// let (nid, hash) = new_hash(&temp_dir);
/// ```
pub fn new_hash(meta_dir: &PathBuf) -> (String, String) {
    let mut len = 4;
    let mut nid = new_id(len);
    let mut hash = blake3::hash(nid.as_bytes()).to_hex().to_string();
    while meta_dir.join(&hash).is_file() {
        nid = new_id(len);
        hash = blake3::hash(nid.as_bytes()).to_hex().to_string();
        len += 1;
    }
    debug!("New ID / BLAKE3 hash generated: {} / {}", &nid, &hash);
    (nid, hash)
}

/// Creates the lesma storage directory
pub fn create_lesma_storage(storage: &PathBuf) -> Result<(), String> {
    let data_dir = storage.join("data");
    let meta_dir = storage.join("meta");
    // Create base directory
    if ! storage.is_dir() {
        create_dir_all(&storage).map_err(|e| {format!("Unable to create lesma storage directory: {}", e)})?;
        info!("lesma storage directory created");
    }
    // Create data directory
    if ! data_dir.is_dir() {
        create_dir(&data_dir).map_err(|e| {format!("Unable to create data directory inside lesma storage directory: {}", e)})?;
        info!("lesma data directory created");
    }
    // Create meta directory
    if ! meta_dir.is_dir() {
        create_dir(&meta_dir).map_err(|e| {format!("Unable to create meta directory inside lesma storage directory: {}", e)})?;
        info!("lesma meta directory created");
    }
    Ok(())
}

/// Creates the sample lesma
pub fn create_sample_lesma(storage: &PathBuf) -> Result<(), String> {
    let id = "lesma";
    let hash = "d887e6b1413f5dc4892bb390438e033eaf5dab94f9064eee73f7ba64f702f1ec";
    if ! storage.join("meta").join(&hash).is_file() {
        let sample = include_str!("lib.rs");
        let lesma = Lesma::from_id_hash(storage.clone(), id, hash);
        lesma.save_plain(0, 876000, None, &sample.to_string()).map_err(|e| {format!("Unable to create sample lesma: {}", e)})?;
        info!("Sample lesma created")
    }
    Ok(())
}

/// Reads lesma metadata from meta file
pub fn read_meta_from_file(meta_file: PathBuf) -> Result<LesmaMeta, Error> {
    // Read file and deserialize JSON metadata
    let meta_json = read_to_string(&meta_file)?;
    let lesma_meta = json::from_str::<LesmaMeta>(&meta_json).map_err(|e| Error::new(ErrorKind::InvalidData, e))?;
    Ok(lesma_meta)
}

/// Returns limit default value in human readable format.
///
/// # Example
///
/// ```
/// use lesma::human_default_limit;
///
/// let default_limit = human_default_limit(0);
/// assert_eq!("unlimited".to_string(), default_limit);
///
/// let default_limit = human_default_limit(2);
/// assert_eq!("2".to_string(), default_limit);
/// ```
pub fn human_default_limit(default_limit: u8) -> String {
    if default_limit > 0 {
        default_limit.to_string()
    } else {
        "unlimited".to_string()
    }
}

/// Returns expire default value in human readable format. Limit is defined in hours, this function
/// returns the values in hours and days as long as they are more than 24 hours.
///
/// # Example
///
/// ```
/// use lesma::human_default_expire;
///
/// let default_expire = human_default_expire(24);
/// assert_eq!("24 hour(s)", default_expire);
///
/// let default_expire = human_default_expire(50);
/// assert_eq!("50 hour(s) / 2.08 day(s)", default_expire);
///
/// let default_expire = human_default_expire(72);
/// assert_eq!("72 hour(s) / 3 day(s)", default_expire);
/// ```
pub fn human_default_expire(default_expire: u32) -> String {
    if default_expire > 24 {
        let default_expire_days = if default_expire % 24 == 0 {
            format!("{} day(s)", default_expire / 24)
        } else {
            format!("{:.2} day(s)", default_expire as f32 / 24.0)
        };
        format!("{} hour(s) / {}", default_expire, default_expire_days)
    } else {
        format!("{} hour(s)", default_expire)
    }
}

/// Returns maximum expiration value in human readable format. It is defined in hours, this
/// function returns the values in hours and days as long as they are more than 24 hours.
///
/// # Example
///
/// ```
/// use lesma::human_max_expire;
///
/// let max_expire = human_max_expire(24);
/// assert_eq!("24h", max_expire);
///
/// let max_expire = human_max_expire(50);
/// assert_eq!("50h/2.08d", max_expire);
///
/// let max_expire = human_max_expire(72);
/// assert_eq!("72h/3d", max_expire);
/// ```
pub fn human_max_expire(max_expire: u32) -> String {
    if max_expire > 24 {
        let max_expire_days = if max_expire % 24 == 0 {
            format!("{}d", max_expire / 24)
        } else {
            format!("{:.2}d", max_expire as f32 / 24.0)
        };
        format!("{}h/{}", max_expire, max_expire_days)
    } else {
        format!("{}h", max_expire)
    }
}

/// Returns a sanitized URI string.
///
/// This function checks if the host value is included in the whitelist. If it is, it returns its
/// value by adding the protocol (http or https), otherwise it returns a empty string.
pub fn get_uri(https: bool, host: &Host<'_>, domains: &Vec<Host<'static>>) -> String {
    let protocol = if https { "https" } else { "http" };
    let sanitized_host = host.to_absolute(protocol, domains);
    match sanitized_host {
        Some(sanitized_host) => sanitized_host.to_string(),
        None => "".to_string()
    }
}

/// Checks if a lesma has expired
pub fn lesma_has_expired(lesma_meta: &LesmaMeta) -> bool {
    lesma_meta.expire < OffsetDateTime::now_utc()
}

/// Checks if a lesma reach max views
pub fn lesma_reached_max_views(lesma_meta: &LesmaMeta) -> bool {
    lesma_meta.limit != 0 && lesma_meta.current >= lesma_meta.limit
}

/// Highligh plain text
pub fn highligh_plain(plain: &String, extension: &std::ffi::OsStr) -> String {
    // Load syntax set and theme set
    let ps = SyntaxSet::load_defaults_newlines();
    let mut ts = ThemeSet::load_defaults();
    ts.themes.get_mut("base16-ocean.dark").unwrap().settings.background = Some(Color {r: 0x00, g: 0x00, b: 0x00, a: 0x00});
    match ps.find_syntax_by_extension(extension.to_str().unwrap()) {
        Some(syntax) => {
            let mut h = HighlightLines::new(syntax, &ts.themes["base16-ocean.dark"]);
            let mut highlighted_plain = String::new();
            for line in LinesWithEndings::from(&plain) {
                let ranges: Vec<(Style, &str)> = h.highlight_line(line, &ps).unwrap();
                highlighted_plain.push_str(&as_24_bit_terminal_escaped(&ranges[..], true));
            }
            highlighted_plain
        },
        None => plain.to_string() // Return uncolorized
    }
}

/// Convert lesma into HTML and highligh
pub fn into_html(plain: &String, extension: Option<&std::ffi::OsStr>) -> String {
    // Load syntax set and theme set
    let ps = SyntaxSet::load_defaults_newlines();
    let ts = ThemeSet::load_defaults();
    // Try to determine syntax
    let syntax = if extension.is_none() {
        // Safe to unwrap since it is a valid syntax
        ps.find_syntax_by_extension("txt").unwrap()
    } else {
        match ps.find_syntax_by_extension(extension.unwrap().to_str().unwrap()) {
            Some(syntax) => syntax,
            None => ps.find_syntax_by_extension("txt").unwrap()
        }
    };
    let mut h = HighlightLines::new(syntax, &ts.themes["InspiredGitHub"]);
    let mut html_lesma_data = String::new();
    let mut line_numbers = String::new();
    let mut lines = String::new();
    let mut counter = 1;
    for line in LinesWithEndings::from(&plain) {
        let regions = h.highlight_line(&line, &ps).unwrap();
        let html = styled_line_to_highlighted_html(&regions[..], IncludeBackground::No).unwrap();
        line_numbers.push_str(&format!("<span class=\"normal\">{}</span>\n", counter));
        lines.push_str(&format!("<a id=\"n-{}\" name=\"n-{}\"></a>{}", counter, counter, html));
        counter +=1;
    }
    html_lesma_data.push_str("<table class=\"highlighttable\"><tr><td class=\"linenos\"><div class=\"linenodiv\"><pre>");
    html_lesma_data.push_str(&line_numbers);
    html_lesma_data.push_str("</pre></div></td><td class=\"code\"><div class=\"highlight\"><pre><span></span>");
    html_lesma_data.push_str(&lines);
    html_lesma_data.push_str("</pre></div></td></tr></table>");
    html_lesma_data
}

#[cfg(test)]
mod tests {
    use super::*;

    fn new_temp_dir() -> PathBuf {
        use rand::distributions::{Distribution, Alphanumeric};
        let mut rnd_name: String = Alphanumeric
            .sample_iter(&mut rand::thread_rng())
            .take(64)
            .map(char::from)
            .collect();
        while std::env::temp_dir().join(&rnd_name).is_dir() {
            rnd_name = Alphanumeric
                .sample_iter(&mut rand::thread_rng())
                .take(64)
                .map(char::from)
                .collect();
        }
        let temp_dir = std::env::temp_dir().join(&rnd_name);
        create_dir_all(&temp_dir).expect("The temporary directory is expected to be created");
        temp_dir
    }

    #[test]
    fn test_new_id() {
        let nid = new_id(6);
        assert_eq!(12, nid.len());
    }

    #[test]
    fn test_new_hash() {
        let temp_dir = std::env::temp_dir();
        let (nid, hash) = new_hash(&temp_dir);
        assert!(nid.len() >= 4);
        assert_eq!(64, hash.len());
    }

    #[test]
    fn test_b3hasher() {
        let mut b3hasher = B3Hasher(blake3::Hasher::new());
        b3hasher.update(b"some text");
        assert_eq!(
            "a0a1c159952a5c5fef1fe3ac3dca48da36ee61ede3e8b5c79fea5458d4db1c7d",
            b3hasher.finalize()
        );
    }

    #[test]
    fn test_create_lesma_storage() {
        let temp_dir = new_temp_dir();
        assert!(create_lesma_storage(&temp_dir).is_ok());
        remove_dir_all(&temp_dir).expect("The temporary directory is expected to be deleted");
    }

    #[test]
    fn test_create_sample_lesma() {
        let sample = include_str!("lib.rs");
        let lesma_hash = blake3::hash(sample.as_bytes()).to_hex().to_string();
        let hash = "d887e6b1413f5dc4892bb390438e033eaf5dab94f9064eee73f7ba64f702f1ec";
        let temp_dir = new_temp_dir();
        let counter_file = temp_dir.join("data").join(&lesma_hash).join("_counter");
        let data_file = temp_dir.join("data").join(&lesma_hash).join("_data");
        let meta_file = temp_dir.join("meta").join(hash);
        let expected_meta = format!("{{\"hash\":\"{}\",\"password\":null,\"name\":\"lesma\",\"binary\":false,\"limit\":0,\"current\":0", lesma_hash);
        // This error occurs because there is no directory structure created
        assert!(create_sample_lesma(&temp_dir).is_err());
        create_lesma_storage(&temp_dir).expect("The lesma storage directory structure is expected to be created");
        assert!(create_sample_lesma(&temp_dir).is_ok());
        assert!(temp_dir.join("data").join(&lesma_hash).is_dir());
        assert!(counter_file.is_file());
        assert!(data_file.is_file());
        assert!(meta_file.is_file());
        let readed_counter = read_to_string(&counter_file).expect("The lesma counter is expected to be readed");
        let readed_data = read_to_string(&data_file).expect("The lesma data is expected to be readed");
        let readed_meta = read_to_string(&meta_file).expect("The lesma meta is expected to be readed");
        assert_eq!("1", readed_counter);
        assert_eq!(sample.to_string(), readed_data);
        assert!(readed_meta.starts_with(&expected_meta));
        remove_dir_all(&temp_dir).expect("The temporary directory is expected to be deleted");
    }

    #[test]
    fn test_get_uri() {
        let domains = [Host::new(uri!("localhost:8000")), Host::new(uri!("127.0.0.1:8000")), Host::new(uri!("lesma.eu"))].to_vec();
        let host = Host::new(uri!("localhost:8000"));
        assert_eq!("http://localhost:8000", get_uri(false, &host, &domains));
        let host = Host::new(uri!("127.0.0.1:8000"));
        assert_eq!("https://127.0.0.1:8000", get_uri(true, &host, &domains));
        let host = Host::new(uri!("lesma.eu"));
        assert_eq!("https://lesma.eu", get_uri(true, &host, &domains));
        let host = Host::new(uri!("false.host"));
        assert_eq!("", get_uri(true, &host, &domains));
    }

    #[test]
    fn test_save_plain() {
        let lesma_hash = "d887e6b1413f5dc4892bb390438e033eaf5dab94f9064eee73f7ba64f702f1ec";
        let sample = "lesma".to_string();
        let temp_dir = new_temp_dir();
        let lesma = Lesma::new(temp_dir.clone());
        let counter_file = temp_dir.join("data").join(&lesma_hash).join("_counter");
        let data_file = temp_dir.join("data").join(&lesma_hash).join("_data");
        let meta_file = temp_dir.join("meta").join(&lesma.hash);
        create_lesma_storage(&temp_dir).expect("The lesma storage directory structure is expected to be created");
        // Saves a new lesma with password
        let save_plain_result = lesma.save_plain(0, 1, Some(sample.clone()), &sample);
        assert!(save_plain_result.is_ok());
        assert!(temp_dir.join("data").join(&lesma_hash).is_dir());
        assert!(counter_file.is_file());
        assert!(data_file.is_file());
        assert!(meta_file.is_file());
        let expected_meta = format!("{{\"hash\":\"{}\",\"password\":\"{}\",\"name\":\"lesma\",\"binary\":false,\"limit\":0,\"current\":0", lesma_hash, lesma_hash);
        let readed_counter = read_to_string(&counter_file).expect("The lesma counter is expected to be readed");
        let readed_data = read_to_string(&data_file).expect("The lesma data is expected to be readed");
        let readed_meta = read_to_string(&meta_file).expect("The lesma meta is expected to be readed");
        assert_eq!("1", readed_counter);
        assert_eq!(sample, readed_data);
        assert!(readed_meta.starts_with(&expected_meta));
        // Saves a new file without a password
        let lesma = Lesma::new(temp_dir.clone());
        let meta_file = temp_dir.join("meta").join(&lesma.hash);
        let save_plain_result = lesma.save_plain(0, 1, None, &sample);
        assert!(save_plain_result.is_ok());
        let expected_meta = format!("{{\"hash\":\"{}\",\"password\":null,\"name\":\"lesma\",\"binary\":false,\"limit\":0,\"current\":0", lesma_hash);
        let readed_counter = read_to_string(&counter_file).expect("The lesma counter is expected to be readed");
        let readed_meta = read_to_string(&meta_file).expect("The lesma meta is expected to be readed");
        assert_eq!("2", readed_counter);
        assert!(readed_meta.starts_with(&expected_meta));
        remove_dir_all(&temp_dir).expect("The temporary directory is expected to be deleted");
    }

    #[test]
    fn test_read_meta() {
        // Hash and lesma hash are the same because the word lesma is used as the origin of both
        let hash = "d887e6b1413f5dc4892bb390438e033eaf5dab94f9064eee73f7ba64f702f1ec";
        let sample = "lesma".to_string();
        let temp_dir = new_temp_dir();
        create_lesma_storage(&temp_dir).expect("The lesma storage directory structure is expected to be created");
        let lesma = Lesma::from_id_hash(temp_dir.clone(), &sample, &hash.to_string());
        lesma.save_plain(0, 1, None, &sample).expect("A plain lesma is expected to be created");
        let lesma_meta = lesma.read_meta().expect("The lesma meta is expected to be readed");
        assert_eq!(hash, lesma_meta.hash);
        assert!(lesma_meta.password.is_none());
        assert_eq!(sample, lesma_meta.name);
        assert!(!lesma_meta.binary);
        assert_eq!(0, lesma_meta.limit);
        assert_eq!(0, lesma_meta.current);
        // Saves same data but with new hash and adding a password
        let new_id = "new lesma";
        let new_hash = "e533f5b6b43ecfe60c28d44caf1696d82ebff44633882d80fd8fc5b6d4f8e32f";
        let lesma = Lesma::from_id_hash(temp_dir.clone(), new_id, new_hash);
        lesma.save_plain(0, 1, Some(sample.clone()), &sample).expect("A plain lesma is expected to be created");
        let lesma_meta = lesma.read_meta().expect("The lesma meta is expected to be readed");
        assert_eq!(hash, lesma_meta.hash);
        assert_eq!(Some(hash.to_string()), lesma_meta.password);
        assert_eq!(sample, lesma_meta.name);
        assert!(!lesma_meta.binary);
        assert_eq!(0, lesma_meta.limit);
        assert_eq!(0, lesma_meta.current);
        remove_dir_all(&temp_dir).expect("The temporary directory is expected to be deleted");
    }

    #[test]
    fn test_read_plain_data() {
        // Hash and lesma hash are the same because the word lesma is used as the origin of both
        let hash = "d887e6b1413f5dc4892bb390438e033eaf5dab94f9064eee73f7ba64f702f1ec".to_string();
        let sample = "lesma".to_string();
        let temp_dir = new_temp_dir();
        create_lesma_storage(&temp_dir).expect("The lesma storage directory structure is expected to be created");
        let lesma = Lesma::from_id_hash(temp_dir.clone(), &sample, &hash);
        lesma.save_plain(0, 1, None, &sample).expect("A plain lesma is expected to be created");
        let lesma_meta = lesma.read_meta().expect("The lesma meta is expected to be readed");
        let lesma_data = lesma.read_plain_data(&lesma_meta, None).expect("The lesma data is expected to be readed");
        assert_eq!(sample, lesma_data);
        lesma.delete(&lesma_meta).expect("A plain lesma is expected to be deleted");
        lesma.save_plain(1, 1, Some(sample.clone()), &sample).expect("A plain lesma is expected to be created");
        let lesma_meta = lesma.read_meta().expect("The lesma meta is expected to be readed");
        let lesma_data = lesma.read_plain_data(&lesma_meta, None);
        assert!(lesma_data.is_err());
        assert_eq!("invalid password".to_string(), lesma_data.unwrap_err().to_string());
        let lesma_data = lesma.read_plain_data(&lesma_meta, Some(sample.clone())).expect("The lesma data is expected to be readed");
        assert_eq!(sample, lesma_data);
        // Reached the read limit
        let lesma_meta = lesma.read_meta().expect("The lesma meta is expected to be readed");
        let lesma_data = lesma.read_plain_data(&lesma_meta, Some(sample.clone()));
        assert!(lesma_data.is_err());
        assert_eq!("lesma expired".to_string(), lesma_data.unwrap_err().to_string());
        remove_dir_all(&temp_dir).expect("The temporary directory is expected to be deleted");
    }

    #[test]
    fn test_update_meta() {
        let lesma_hash = "d887e6b1413f5dc4892bb390438e033eaf5dab94f9064eee73f7ba64f702f1ec";
        let sample = "lesma".to_string();
        let temp_dir = new_temp_dir();
        let lesma = Lesma::new(temp_dir.clone());
        let meta_file = temp_dir.join("meta").join(&lesma.hash);
        create_lesma_storage(&temp_dir).expect("The lesma storage directory structure is expected to be created");
        lesma.save_plain(0, 1, None, &sample).expect("A plain lesma is expected to be created");
        let lesma_meta = lesma.read_meta().expect("The lesma meta is expected to be readed");
        let update_lesma_meta_result = lesma.update_meta(&lesma_meta);
        assert!(update_lesma_meta_result.is_ok());
        let expected_meta = format!("{{\"hash\":\"{}\",\"password\":null,\"name\":\"lesma\",\"binary\":false,\"limit\":0,\"current\":0", lesma_hash);
        let readed_meta = read_to_string(&meta_file).expect("The lesma meta is expected to be readed");
        assert!(readed_meta.starts_with(&expected_meta));
        // Saves a new lesma with limit and using same content
        let lesma = Lesma::new(temp_dir.clone());
        let meta_file = temp_dir.join("meta").join(&lesma.hash);
        lesma.save_plain(2, 1, None, &sample).expect("A plain lesma is expected to be created");
        let lesma_meta = lesma.read_meta().expect("The lesma meta is expected to be readed");
        lesma.update_meta(&lesma_meta).expect("The lesma meta is expected to be updated");
        let expected_meta = format!("{{\"hash\":\"{}\",\"password\":null,\"name\":\"lesma\",\"binary\":false,\"limit\":2,\"current\":1", lesma_hash);
        let readed_meta = read_to_string(&meta_file).expect("The lesma meta is expected to be readed");
        assert!(readed_meta.starts_with(&expected_meta));
        remove_dir_all(&temp_dir).expect("The temporary directory is expected to be deleted");
    }

    #[test]
    fn test_delete() {
        let lesma_hash = "d887e6b1413f5dc4892bb390438e033eaf5dab94f9064eee73f7ba64f702f1ec";
        let sample = "lesma".to_string();
        let temp_dir = new_temp_dir();
        let lesma = Lesma::new(temp_dir.clone());
        let data_dir = temp_dir.join("data").join(&lesma_hash);
        let counter_file = data_dir.join("_counter");
        let data_file = data_dir.join("_data");
        let meta_file = temp_dir.join("meta").join(&lesma.hash);
        create_lesma_storage(&temp_dir).expect("The lesma storage directory structure is expected to be created");
        lesma.save_plain(0, 1, None, &sample).expect("A plain lesma is expected to be created");
        let lesma_meta = lesma.read_meta().expect("The lesma meta is expected to be readed");
        let delete_lesma_result = lesma.delete(&lesma_meta);
        assert!(delete_lesma_result.is_ok());
        assert!(!data_dir.is_dir());
        assert!(!counter_file.is_file());
        assert!(!data_file.is_file());
        assert!(!meta_file.is_file());
        // Save sample lesma again
        lesma.save_plain(0, 1, None, &sample).expect("A plain lesma is expected to be created");
        // Create new lesma with same contents
        let lesma = Lesma::new(temp_dir.clone());
        lesma.save_plain(0, 1, None, &sample).expect("A plain lesma is expected to be created");
        let meta_file = temp_dir.join("meta").join(&lesma.hash);
        let readed_counter = read_to_string(&counter_file).expect("The lesma counter is expected to be readed");
        assert_eq!("2", readed_counter);
        let delete_lesma_result = lesma.delete(&lesma_meta);
        assert!(delete_lesma_result.is_ok());
        assert!(data_dir.is_dir());
        assert!(counter_file.is_file());
        assert!(data_file.is_file());
        assert!(!meta_file.is_file());
        let readed_counter = read_to_string(&counter_file).expect("The lesma counter is expected to be readed");
        assert_eq!("1", readed_counter);
        remove_dir_all(&temp_dir).expect("The temporary directory is expected to be deleted");
    }

    #[test]
    fn test_lesma_has_expired() {
        let mut lesma_meta = LesmaMeta {
            hash: "".to_string(),
            password: None,
            name: "".to_string(),
            binary: false,
            limit: 0,
            current: 0,
            create: OffsetDateTime::now_utc(),
            expire: OffsetDateTime::now_utc() + Duration::hours(1)
        };
        assert!(!lesma_has_expired(&lesma_meta));
        lesma_meta.expire = OffsetDateTime::now_utc() - Duration::hours(1);
        assert!(lesma_has_expired(&lesma_meta));
    }

    #[test]
    fn test_lesma_reached_max_views() {
        let mut lesma_meta = LesmaMeta {
            hash: "".to_string(),
            password: None,
            name: "".to_string(),
            binary: false,
            limit: 0,
            current: 0,
            create: OffsetDateTime::now_utc(),
            expire: OffsetDateTime::now_utc() + Duration::hours(1)
        };
        assert!(!lesma_reached_max_views(&lesma_meta));
        lesma_meta.current = 10;
        assert!(!lesma_reached_max_views(&lesma_meta));
        lesma_meta.current = 0;
        lesma_meta.limit = 2;
        assert!(!lesma_reached_max_views(&lesma_meta));
        lesma_meta.current += 1;
        assert!(!lesma_reached_max_views(&lesma_meta));
        lesma_meta.current += 1;
        assert!(lesma_reached_max_views(&lesma_meta));
        lesma_meta.current += 1;
        assert!(lesma_reached_max_views(&lesma_meta));
    }
}