use anyhow::Result;
use crate::{ ConfigManager, config::Host, input };
use dialoguer::{ Select, Input, Confirm, Editor, theme::ColorfulTheme };
use serde::{ Serialize, Deserialize };
use ssh_key::PrivateKey;
use std::fs;


#[derive(Clone, Debug)]
pub struct PlatformKey {
    pub file: String,
    pub display: String,
}

impl std::fmt::Display for PlatformKey {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.write_str(&self.display)
    }
}


// todo: GPG support
#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Serialize, Deserialize)]
pub enum Platform {
    SSH
}

impl std::fmt::Display for Platform {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.write_str(match self {
            Platform::SSH => "SSH",
        })
    }
}

impl Platform {
    pub fn all() -> Vec<Platform> {
        vec![
            Self::SSH
        ]
    }
    
    pub fn new_host(&self, config: &mut ConfigManager) -> Result<Host> {
        match self {
            Platform::SSH => self.ssh_new_host(config)
        }
    }
    
    pub fn get_keys(&self, config: &ConfigManager) -> Vec<PlatformKey> {
        match self {
            Platform::SSH => self.ssh_get_keys(config),
        }
    }
    pub fn run(&self, host: &mut Host, config: &mut ConfigManager) -> Result<()> {
        match self {
            Platform::SSH => self.ssh_run(host, config),
        }
    }
    
    
    // --- --- ---
    //     SSH
    // --- --- ---
    
    fn ssh_new_config(&self, host: String, port: i16, keyid: PlatformKey) -> String {
        format!(r#"# Generated by Keyman

Host {host}
        HostName {host}
        Port {port}
        IdentityFile {}
"#, keyid.file)
    }
    
    // New host
    fn ssh_new_host(&self, config: &mut ConfigManager) -> Result<Host> {
        println!("- Creating new host entry");
        let keyid = input::get_key(config, self.to_owned())?;
        
        let userhost = loop {
            let inp: String = Input::with_theme(&ColorfulTheme::default())
                .with_prompt("User@Host")
                .interact_text()?;
            
            let split = inp.split("@");
            let split: Vec<String> = split.map(|a| a.to_string()).collect();
            
            if split.len() < 2 {
                println!("Incorrect user@host given. Example: paul@example.com:34; <user>@<host>[:port]");
            } else {
                break split
            }
        };
        
        let user: String = userhost.get(0).unwrap().to_string();
        let mut host: String = userhost.get(1).unwrap().to_string();
        let mut port: i16 = 22;
        
        let _host = host.to_owned();
        let h: Vec<&str> = _host.split(":").collect();
        
        if h.len() > 1 {
            let portstr = h.get(1).unwrap();
            port = i16::from_str_radix(portstr, 10)?;
            host = h.get(0).unwrap().to_string();
        }

        let config_dir = config.config_dir.join("hosts/").join(host.to_owned());
        fs::create_dir_all(config_dir.to_owned()).expect(&format!("Couldnt create_dir_all on {:?}", config_dir.to_owned()));
        let config_file = config_dir.join("config");

        fs::write(config_file.to_owned(), self.ssh_new_config(host.to_owned(), port, keyid.to_owned())).expect(&format!("Couldn't write config at {:?}", config_file.to_owned()));
        
        Ok(Host {
            platform: Platform::SSH,
            id: keyid.file,
            user,
            host,
            port,
            config: config_file.to_owned().to_string_lossy().to_string()
        })
    }
    
    // Get keys
    fn ssh_get_keys(&self, config: &ConfigManager) -> Vec<PlatformKey> {
        let mut keys = vec![];
        let Ok(dir) = std::fs::read_dir(config.search_path.to_owned()) else { panic!("Couldn't read {:?}", config.search_path.to_owned()) };

        for file in dir {
            let Ok(f) = file else { continue };

            match PrivateKey::read_openssh_file(&f.path()) {
                Ok(p) => keys.push(PlatformKey {
                    file: format!("{}", f.path().to_string_lossy()),
                    display: format!("{}: {}", p.fingerprint(ssh_key::HashAlg::Sha256), f.file_name().to_string_lossy())
                }),
                // Not a private key
                Err(_) => continue
            };
        }

        keys
    }
    
    // Run
    fn ssh_run(&self, host: &mut Host, config: &mut ConfigManager) -> Result<()> {
        Ok(loop {
            let action = Select::with_theme(&ColorfulTheme::default())
                .with_prompt(format!("{}@{}", host.user.to_owned(), host.host.to_owned()))
                .item("Connect")
                .item("Edit config")
                .item("Edit definition")
                .item("Delete")
                .item("Back")
                .default(0)
                .interact()?;
            
            match action {
                0 => { // Connect
                    // TODO: clear screen before connect
                    std::process::Command::new("ssh")
                        .arg("-F")
                        .arg(host.config.to_owned())
                        .arg("-l")
                        .arg(host.user.to_owned())
                        .arg(host.host.to_owned()).spawn()?.wait()?;
                }
                1 => { // Edit config
                    // TODO: replace this with configuer::editor
//                    if let Some(cnf) = Editor::new().edit(fs::read_to_string(config.config_dir.join("config"))?.as_str())? {
//                        fs::write(config.config_dir.join("config"), cnf)?;
//                    }
                    let editor = std::env::var("EDITOR").expect("EDITOR is not set");
                    std::process::Command::new(editor)
                        .arg(host.config.to_owned())
                        .spawn()?.wait()?;
                }
                2 => { // Edit definition
                    let edited_host = host.edit()?;
                    config.configs.remove(host);
                    config.configs.insert(edited_host.to_owned());
                    host.clone_from(&edited_host);
                    config.save();
                }
                3 => { // Delete
                    let confirm = Confirm::with_theme(&ColorfulTheme::default())
                        .with_prompt("Are you sure you want to delete this definition?")
                        .default(false)
                        .interact()?;

                    if confirm {
                        let mut conf = std::path::PathBuf::from(host.config.to_owned());
                        conf.pop();

                        config.configs.remove(host);
                        config.save();
                        fs::remove_dir_all(conf)?;
                        break;
                    }
                } // Back
                4 => break,
                _ => ()
            }
        })
    }
    
    
    // --- --- ---
    //     GPG
    // --- --- ---
}