use super::{Cmd, Commands};
use clap::{Arg, ArgAction, ArgMatches, Command};
use clap_complete::shells;
use clap_complete_nushell::Nushell;
use std::{
    error::Error,
    fs,
    io::{self, ErrorKind},
    path::PathBuf,
};

#[derive(Debug)]
pub struct Bootstrap {
    name: &'static str,
    path: Option<crate::Path>,
}

pub const BOOTSTRAP: Bootstrap = Bootstrap {
    name: "bootstrap",
    path: None,
};

impl Bootstrap {
    fn all() -> clap::Command {
        Command::new("all").about("Install everything").args([
            Arg::new("soft")
                .help("Install soft links instead of hardlinks")
                .short('s')
                .long("soft")
                .action(ArgAction::SetTrue),
            Arg::new("all")
                .help("Install completions for all supported shells")
                .short('a')
                .long("all")
                .conflicts_with_all(["bash", "fish", "nu", "pwsh", "zsh"])
                .action(ArgAction::SetTrue),
            Arg::new("bash")
                .help("Bash shell completions")
                .short('b')
                .long("bash")
                .action(ArgAction::SetTrue),
            Arg::new("fish")
                .help("Fish shell completions")
                .short('f')
                .long("fish")
                .action(ArgAction::SetTrue),
            Arg::new("nu")
                .help("Nushell completions")
                .short('n')
                .long("nu")
                .action(ArgAction::SetTrue),
            Arg::new("pwsh")
                .help("PowerShell completions")
                .short('p')
                .long("pwsh")
                .action(ArgAction::SetTrue),
            Arg::new("zsh")
                .help("Zshell completions")
                .short('z')
                .long("zsh")
                .action(ArgAction::SetTrue),
        ])
    }

    fn links() -> clap::Command {
        Command::new("links")
            .about("Install links for each applet")
            .arg(
                Arg::new("soft")
                    .help("Install soft links instead of hardlinks")
                    .short('s')
                    .long("soft")
                    .action(ArgAction::SetTrue),
            )
    }

    fn manpages() -> clap::Command {
        Command::new("manpages")
            .about("Install Unix man pages")
            .alias("man")
    }

    fn completions() -> clap::Command {
        Command::new("completions")
            .about("Install shell completions")
            .alias("comp")
            .args([
                Arg::new("all")
                    .help("Install completions for all supported shells")
                    .short('a')
                    .long("all")
                    .exclusive(true)
                    .action(ArgAction::SetTrue),
                Arg::new("bash")
                    .help("Bash shell completions")
                    .short('b')
                    .long("bash")
                    .action(ArgAction::SetTrue),
                Arg::new("fish")
                    .help("Fish shell completions")
                    .short('f')
                    .long("fish")
                    .action(ArgAction::SetTrue),
                Arg::new("nu")
                    .help("Nushell completions")
                    .short('n')
                    .long("nu")
                    .action(ArgAction::SetTrue),
                Arg::new("pwsh")
                    .help("PowerShell completions")
                    .short('p')
                    .long("pwsh")
                    .action(ArgAction::SetTrue),
                Arg::new("zsh")
                    .help("Zshell completions")
                    .short('z')
                    .long("zsh")
                    .action(ArgAction::SetTrue),
            ])
    }
}

impl Cmd for Bootstrap {
    fn name(&self) -> &str {
        self.name
    }

    fn cli(&self) -> clap::Command {
        Command::new(self.name)
            .version(env!("CARGO_PKG_VERSION"))
            .author("Nathan Fisher")
            .about("Install shitbox into the filesystem")
            .long_about("Install symlinks, manpages and shell completions")
            .args([
                Arg::new("prefix")
                    .help("The directory path under which to install")
                    .short('p')
                    .long("prefix")
                    .num_args(1)
                    .default_value("/")
                    .required(false),
                Arg::new("usr")
                    .help("Use /usr")
                    .long_help(
                        "Split the installation so that some applets go into /bin | /sbin\n\
                    while others are placed into /usr/bin | /usr/sbin",
                    )
                    .short('u')
                    .long("usr")
                    .action(ArgAction::SetTrue),
                Arg::new("soft")
                    .help("Install soft links instead of hardlinks")
                    .short('s')
                    .long("soft")
                    .action(ArgAction::SetTrue),
            ])
            .subcommands([
                Self::all(),
                Self::links(),
                Self::manpages(),
                Self::completions(),
            ])
    }

    fn run(&self, matches: Option<&ArgMatches>) -> Result<(), Box<dyn Error>> {
        let matches = if let Some(m) = matches {
            m
        } else {
            return Err(io::Error::new(ErrorKind::Other, "No input").into());
        };
        if let Some(prefix) = matches.get_one::<String>("prefix") {
            let commands = super::COMMANDS
                .get()
                .ok_or_else(|| io::Error::new(ErrorKind::Other, "Cannot get commands list"))?;
            let usr = matches.get_flag("usr");
            if let Some(progpath) = crate::progpath() {
                let mut outpath = PathBuf::from(prefix);
                outpath.push("bin");
                println!("Installing binary:");
                if !outpath.exists() {
                    fs::create_dir_all(&outpath)?;
                    println!("    mkdir: {}", outpath.display());
                }
                outpath.push(env!("CARGO_PKG_NAME"));
                fs::copy(&progpath, &outpath)?;
                println!(
                    "    install: {} -> {}",
                    progpath.display(),
                    outpath.display()
                );
            }
            match matches.subcommand() {
                Some(("links", matches)) => {
                    commands.links(prefix, usr, matches)?;
                }
                Some(("manpages", _matches)) => {
                    commands.manpages(prefix)?;
                }
                Some(("completions", matches)) => {
                    commands.completions(prefix, matches)?;
                }
                Some(("all", matches)) => {
                    commands.links(prefix, usr, matches)?;
                    commands.manpages(prefix)?;
                    commands.completions(prefix, matches)?;
                }
                _ => {}
            }
        }
        Ok(())
    }

    fn path(&self) -> Option<crate::Path> {
        self.path
    }
}

pub trait Bootstrappable {
    fn manpages(&self, prefix: &str) -> Result<(), io::Error>;
    fn completions(&self, prefix: &str, matches: &ArgMatches) -> Result<(), io::Error>;
    fn links(&self, prefix: &str, usr: bool, cmd: &ArgMatches) -> Result<(), Box<dyn Error>>;
}

impl<'a> Bootstrappable for Commands<'a> {
    fn manpages(&self, prefix: &str) -> Result<(), io::Error> {
        println!("Generating Unix man pages:");
        self.items.iter().try_for_each(|cmd| cmd.manpage(prefix))?;
        Ok(())
    }

    fn completions(&self, prefix: &str, matches: &ArgMatches) -> Result<(), io::Error> {
        println!("Generating completions:");
        if matches.get_flag("bash") || matches.get_flag("all") {
            let outdir: PathBuf = [prefix, "share", "bash-completion", "completion"]
                .iter()
                .collect();
            self.items
                .iter()
                .try_for_each(|cmd| Self::completion(&outdir, cmd, shells::Bash))?;
        }
        if matches.get_flag("fish") || matches.get_flag("all") {
            let outdir: PathBuf = [prefix, "share", "fish", "completions"].iter().collect();
            self.items
                .iter()
                .try_for_each(|cmd| Self::completion(&outdir, cmd, shells::Fish))?;
        }
        if matches.get_flag("nu") || matches.get_flag("all") {
            let outdir: PathBuf = [prefix, "share", "nu", "completions"].iter().collect();
            self.items
                .iter()
                .try_for_each(|cmd| Self::completion(&outdir, cmd, Nushell))?;
        }
        if matches.get_flag("pwsh") || matches.get_flag("all") {
            let outdir: PathBuf = [prefix, "share", "pwsh", "completions"].iter().collect();
            self.items
                .iter()
                .try_for_each(|cmd| Self::completion(&outdir, cmd, shells::PowerShell))?;
        }
        if matches.get_flag("zsh") || matches.get_flag("all") {
            let outdir: PathBuf = [prefix, "share", "zsh", "site-functions"].iter().collect();
            self.items
                .iter()
                .try_for_each(|cmd| Self::completion(&outdir, cmd, shells::Zsh))?;
        }
        Ok(())
    }

    fn links(&self, prefix: &str, usr: bool, cmd: &ArgMatches) -> Result<(), Box<dyn Error>> {
        println!("Generating links:");
        let mut binpath = PathBuf::from(prefix);
        binpath.push("bin");
        if !binpath.exists() {
            fs::create_dir_all(&binpath)?;
            println!("    mkdir: {}", binpath.display());
        }
        binpath.pop();
        binpath.push("sbin");
        if !binpath.exists() {
            fs::create_dir_all(&binpath)?;
            println!("    mkdir: {}", binpath.display());
        }
        if usr {
            binpath.pop();
            binpath.push("usr");
            binpath.push("bin");
            if !binpath.exists() {
                fs::create_dir_all(&binpath)?;
                println!("    mkdir: {}", binpath.display());
            }
            binpath.pop();
            binpath.push("sbin");
            if !binpath.exists() {
                fs::create_dir_all(&binpath)?;
                println!("    mkdir: {}", binpath.display());
            }
        }
        let soft = cmd.get_flag("soft");
        self.items
            .iter()
            .try_for_each(|cmd| cmd.link(prefix, usr, soft))?;
        Ok(())
    }
}