service-install 0.5.7

use std::collections::HashMap;
use std::path::{Path, PathBuf};

pub mod cron;
pub(crate) mod extract_path;
pub mod systemd;

use sysinfo::Pid;

use crate::install::RemoveStep;

use self::systemd::FindExeError;

use super::builder::Trigger;
use super::files::{DisableError, NoHomeError, TargetInUseError};
use super::{InstallStep, Mode};

type Steps = Vec<Box<dyn InstallStep>>;
type RSteps = Vec<Box<dyn RemoveStep>>;

/// Allowed init systems, set using: [`install::Spec::allowed_inits()`](super::Spec::allowed_inits)
#[derive(Debug, Clone)]
pub enum System {
    Systemd,
    Cron,
}

type ExeLocation = PathBuf;
impl System {
    pub(crate) fn name(&self) -> &'static str {
        match self {
            System::Systemd => "Systemd",
            System::Cron => "Cron",
        }
    }
    pub(crate) fn not_available(&self) -> Result<bool, SetupError> {
        match self {
            System::Systemd => systemd::not_available(),
            System::Cron => Ok(cron::not_available()),
        }
    }
    pub(crate) fn disable_steps(
        &self,
        target: &Path,
        pid: Pid,
        mode: Mode,
        run_as: Option<&str>,
    ) -> Result<Vec<Box<dyn InstallStep>>, TargetInUseError> {
        match self {
            System::Systemd => Ok(systemd::disable_step(target, mode).map_err(DisableError::from)?),
            System::Cron => {
                Ok(cron::disable::step(target, pid, run_as).map_err(DisableError::from)?)
            }
        }
    }
    pub(crate) fn set_up_steps(&self, params: &Params) -> Result<Steps, SetupError> {
        match self {
            System::Systemd => systemd::set_up_steps(params),
            System::Cron => cron::set_up_steps(params),
        }
    }
    pub(crate) fn tear_down_steps(
        &self,
        bin_name: &str,
        mode: Mode,
        user: Option<&str>,
    ) -> Result<Option<(RSteps, ExeLocation)>, TearDownError> {
        match self {
            System::Systemd => systemd::tear_down_steps(mode),
            System::Cron => cron::tear_down_steps(bin_name, mode, user),
        }
    }

    pub(crate) fn all() -> Vec<System> {
        vec![Self::Systemd, Self::Cron]
    }

    pub(crate) fn is_init_path(&self, path: &Path) -> Result<bool, PathCheckError> {
        match self {
            System::Systemd => systemd::path_is_systemd(path),
            System::Cron => Ok(cron::is_init_path(path)),
        }
    }
}

#[derive(Debug, thiserror::Error)]
#[error("The path could not be resolved, error {0}")]
pub struct PathCheckError(std::io::Error);

#[derive(thiserror::Error, Debug)]
pub enum SetupError {
    #[error("systemd specific error")]
    Systemd(
        #[from]
        #[source]
        systemd::Error,
    ),
    #[error("Error while setting up crontab rule")]
    Cron(
        #[from]
        #[source]
        cron::setup::Error,
    ),
    #[error("could not find current users home dir")]
    NoHome(#[from] NoHomeError),
}

#[derive(thiserror::Error, Debug)]
pub enum TearDownError {
    #[error("Cron specific error")]
    Cron(
        #[from]
        #[source]
        cron::teardown::Error,
    ),
    #[error("Error while setting up systemd service")]
    Systemd(
        #[from]
        #[source]
        systemd::Error,
    ),
    #[error("Could not find current users home dir")]
    NoHome(
        #[from]
        #[source]
        NoHomeError,
    ),
    #[error("No service file while there is a timer file")]
    TimerWithoutService,
    #[error("Could not find path to executable")]
    FindingExePath(
        #[from]
        #[source]
        FindExeError,
    ),
    #[error(
        "Found multiple different paths in services, do not know which to remove, paths: {0:?}"
    )]
    MultipleExePaths(Vec<PathBuf>),
}

#[derive(Debug, Clone)]
pub(crate) struct Params {
    pub(crate) name: String,
    pub(crate) bin_name: &'static str,
    pub(crate) description: Option<String>,

    pub(crate) exe_path: PathBuf,
    pub(crate) exe_args: Vec<String>,
    pub(crate) environment: HashMap<String, String>,
    pub(crate) working_dir: Option<PathBuf>,

    pub(crate) trigger: Trigger,
    pub(crate) run_as: Option<String>,
    pub(crate) mode: Mode,
}

impl Params {
    fn description(&self) -> String {
        self.description
            .clone()
            .unwrap_or_else(|| format!("starts {}", self.name))
    }
}

pub(crate) const COMMENT_PREAMBLE: &str = "# created by: ";
pub(crate) const COMMENT_SUFFIX: &str = " during its installation\n# might get removed by it in the future.\n# Remove this comment to prevent that";

fn autogenerated_comment(bin_name: &str) -> String {
    format!("{COMMENT_PREAMBLE}'{bin_name}'{COMMENT_SUFFIX}")
}

trait ShellEscape {
    fn shell_escaped(&self) -> String;
}

impl ShellEscape for std::path::PathBuf {
    fn shell_escaped(&self) -> String {
        let path = self.display().to_string();
        let path = std::borrow::Cow::Owned(path);
        let path = shell_escape::unix::escape(path);
        path.into_owned()
    }
}

impl ShellEscape for &std::path::Path {
    fn shell_escaped(&self) -> String {
        let path = self.display().to_string();
        let path = std::borrow::Cow::Owned(path);
        let path = shell_escape::unix::escape(path);
        path.into_owned()
    }
}

impl ShellEscape for String {
    fn shell_escaped(&self) -> String {
        let s = std::borrow::Cow::Borrowed(self.as_str());
        let s = shell_escape::unix::escape(s);
        s.into_owned()
    }
}

// man 7 syntax
//
// For settings where quoting is allowed, the following general rules apply:
// double quotes ("...") and single quotes ('...') may be used to wrap a whole
// item (the opening quote may appear only at the beginning or after whitespace
// that is not quoted, and the closing quote must be followed by whitespace
// or the end of line), in which case everything until the next matching
// quote becomes part of the same item. Quotes themselves are removed. C-style
// escapes are supported.
trait SystemdEscape {
    fn systemd_escape(&self) -> String;
}

impl SystemdEscape for String {
    fn systemd_escape(&self) -> String {
        // escaped / -> // and escaped " -> /"
        let mut quotes_escaped = self.replace('"', "\\\"");
        quotes_escaped.push('"');
        quotes_escaped.insert(0, '"');
        quotes_escaped
    }
}

impl SystemdEscape for &std::path::Path {
    fn systemd_escape(&self) -> String {
        self.display().to_string().systemd_escape()
    }
}

impl SystemdEscape for &str {
    fn systemd_escape(&self) -> String {
        self.to_string().systemd_escape()
    }
}

impl SystemdEscape for std::path::PathBuf {
    fn systemd_escape(&self) -> String {
        self.display().to_string().systemd_escape()
    }
}

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

    #[test]
    fn escape_with_exclamation() {
        let s = "message with spaces/1/11:00..16:30/!"
            .to_string()
            .systemd_escape();
        assert_eq!(&s, "\"message with spaces/1/11:00..16:30/!\"");
    }

    #[test]
    fn escape_single_letter() {
        let s = "v".to_string().systemd_escape();
        assert_eq!(&s, "\"v\"");
    }
}