//! Shared command-line definitions for the crabidy binaries
//! (`crabidy-server`, `cbd-tui`, `cbd`), plus a feature-gated gRPC executor
//! for the remote `library`/`queue`/`global` commands.
//!
//! See `architecture/cli.md`. The clap types live here so every binary shares
//! one command surface and each binary's `build.rs` can generate shell
//! completions and man pages from its own top-level [`clap::Command`] with the
//! default (clap-only) feature set. The `client` feature adds [`run_remote`],
//! which the binaries call to execute a remote command against a running
//! server.

use clap::{Args, Parser, Subcommand, ValueEnum};

/// A server auth role. The `ValueEnum` names double as the basic-auth user
/// names the server expects.
#[derive(Debug, Clone, Copy, PartialEq, Eq, ValueEnum)]
pub enum Role {
    /// Full control (the normal user).
    Owner,
    /// Anything on the queue and playback, no library writes.
    QueueOwner,
    /// May browse and append to the queue; nothing else.
    Appender,
}

impl Role {
    /// The basic-auth user name for this role.
    pub fn user_name(self) -> &'static str {
        match self {
            Role::Owner => "owner",
            Role::QueueOwner => "queue-owner",
            Role::Appender => "queue-appender",
        }
    }
}

/// Connection flags shared by every remote command. Defaults match the client
/// config; a flag overrides the config-file value.
#[derive(Debug, Clone, Args)]
pub struct RemoteArgs {
    /// Server address (default: the client config's, else localhost).
    #[arg(short, long)]
    pub address: Option<String>,
    /// Basic-auth user / role name (empty against an open server).
    #[arg(short, long)]
    pub user: Option<String>,
    /// Basic-auth password.
    #[arg(short, long)]
    pub password: Option<String>,
}

/// Library operations against a running server.
#[derive(Debug, Subcommand)]
pub enum LibraryCmd {
    /// List a node's child nodes and tracks (default path `/`).
    List {
        #[arg(default_value = "/")]
        path: String,
    },
    /// Create a child node under a creatable parent (e.g. a search term).
    Create { parent: String, title: String },
    /// Rename an editable node.
    Rename { path: String, title: String },
    /// Delete a deletable node or track (never touches the content store).
    Delete { path: String },
    /// Save a subtree as a link bookmark under `/crabidy/<name>`.
    Save { path: String, name: String },
    /// Capture a subtree under `/crabidy/<name>` (downloads audio).
    Capture { path: String, name: String },
}

/// Queue operations against a running server.
#[derive(Debug, Subcommand)]
pub enum QueueCmd {
    /// Print the current queue.
    Show,
    /// Append tracks/subtrees (by library path) to the end of the queue.
    Append { paths: Vec<String> },
    /// Insert tracks/subtrees at a position.
    Insert { position: u32, paths: Vec<String> },
    /// Replace the whole queue with the given tracks/subtrees.
    Replace { paths: Vec<String> },
    /// Remove queue entries by position.
    Remove { positions: Vec<u32> },
    /// Clear the queue (optionally keeping the current track).
    Clear {
        #[arg(long)]
        keep_current: bool,
    },
    /// Jump to a queue position.
    SetCurrent { position: u32 },
    /// Link-save the current queue as `/crabidy/<name>`.
    Save { name: String },
    /// Capture the current queue into `/crabidy/<name>` (downloads audio).
    Capture { name: String },
    /// Toggle shuffle.
    Shuffle,
    /// Toggle repeat.
    Repeat,
}

/// Playback and global operations against a running server.
#[derive(Debug, Subcommand)]
pub enum GlobalCmd {
    /// Toggle play/pause.
    Play,
    /// Stop playback.
    Stop,
    /// Skip to the next track.
    Next,
    /// Go to the previous track.
    Prev,
    /// Restart the current track.
    Restart,
    /// Toggle mute.
    Mute,
    /// Change the volume by a delta in [-1.0, 1.0] (e.g. `0.05`, `-0.1`).
    Volume { delta: f32 },
}

/// The remote command groups an executor can run (`client` feature).
#[derive(Debug, Subcommand)]
pub enum RemoteCmd {
    /// Library operations.
    #[command(subcommand)]
    Library(LibraryCmd),
    /// Queue operations.
    #[command(subcommand)]
    Queue(QueueCmd),
    /// Playback / global operations.
    #[command(subcommand)]
    Global(GlobalCmd),
}

/// `guard <role> [password]`: hash a role password and (unless `--no-config`)
/// write it into `crabidy-server.toml`'s `[auth]`.
#[derive(Debug, Args)]
pub struct GuardArgs {
    /// Which role's password to set.
    pub role: Role,
    /// The password. If omitted, it is read from stdin (pipe-friendly, and
    /// keeps it out of the process list).
    pub password: Option<String>,
    /// Only print the PHC hash; do not modify `crabidy-server.toml`.
    #[arg(long)]
    pub no_config: bool,
}

/// `scan <path> [--capture|--move]`: index a music folder.
#[derive(Debug, Args)]
pub struct ScanArgs {
    /// Directory to walk for playable files.
    pub path: std::path::PathBuf,
    /// Copy each file into the content store; the toml points there.
    #[arg(long)]
    pub capture: bool,
    /// Move each file into the content store instead of copying.
    #[arg(long, name = "move")]
    pub move_: bool,
}

/// `auth <role> [password]`: write a role + cleartext password into the client
/// config.
#[derive(Debug, Args)]
pub struct AuthArgs {
    /// Which role to authenticate as.
    pub role: Role,
    /// The cleartext password (read from stdin if omitted).
    pub password: Option<String>,
    /// Also set the server address in the client config.
    #[arg(short, long)]
    pub address: Option<String>,
}

/// `completions <shell>`: print a completion script to stdout.
#[derive(Debug, Args)]
pub struct CompletionsArgs {
    /// Target shell.
    pub shell: clap_complete::Shell,
}

/// Subcommands of `crabidy-server`.
#[derive(Debug, Subcommand)]
pub enum ServerCommand {
    /// Set a role password (hash + write config).
    Guard(GuardArgs),
    /// Index a music folder with `.cbd-track.toml` files.
    Scan(ScanArgs),
    /// Library operations against a running server.
    #[command(subcommand)]
    Library(LibraryCmd),
    /// Queue operations against a running server.
    #[command(subcommand)]
    Queue(QueueCmd),
    /// Playback / global operations against a running server.
    #[command(subcommand)]
    Global(GlobalCmd),
    /// List the audio output devices (to pick `[audio] device`).
    AudioDevices,
    /// Print a shell completion script.
    Completions(CompletionsArgs),
}

/// `crabidy-server`: no subcommand runs the server.
#[derive(Debug, Parser)]
#[command(name = "crabidy-server", author, version, about)]
pub struct ServerCli {
    #[command(flatten)]
    pub remote: RemoteArgs,
    #[command(subcommand)]
    pub command: Option<ServerCommand>,
}

/// Subcommands of `cbd-tui`.
#[derive(Debug, Subcommand)]
pub enum TuiCommand {
    /// Write a role + password into the client config.
    Auth(AuthArgs),
    #[command(subcommand)]
    Library(LibraryCmd),
    #[command(subcommand)]
    Queue(QueueCmd),
    #[command(subcommand)]
    Global(GlobalCmd),
    /// Print a shell completion script.
    Completions(CompletionsArgs),
}

/// `cbd-tui`: no subcommand runs the TUI.
#[derive(Debug, Parser)]
#[command(name = "cbd-tui", author, version, about)]
pub struct TuiCli {
    #[command(flatten)]
    pub remote: RemoteArgs,
    /// Show the frequency-spectrum bars under the track progress.
    #[arg(long)]
    pub spectrum: Option<bool>,
    #[command(subcommand)]
    pub command: Option<TuiCommand>,
}

/// Subcommands of `cbd` — the union of the server and client commands.
#[derive(Debug, Subcommand)]
pub enum CbdCommand {
    Guard(GuardArgs),
    Scan(ScanArgs),
    Auth(AuthArgs),
    #[command(subcommand)]
    Library(LibraryCmd),
    #[command(subcommand)]
    Queue(QueueCmd),
    #[command(subcommand)]
    Global(GlobalCmd),
    /// List the audio output devices (to pick `[audio] device`).
    AudioDevices,
    /// Print a shell completion script.
    Completions(CompletionsArgs),
}

/// `cbd`: no subcommand runs the in-process server + TUI.
#[derive(Debug, Parser)]
#[command(name = "cbd", author, version, about)]
pub struct CbdCli {
    #[command(flatten)]
    pub remote: RemoteArgs,
    #[arg(long)]
    pub spectrum: Option<bool>,
    #[command(subcommand)]
    pub command: Option<CbdCommand>,
}

/// Resolved connection settings for the executor (owned, unlike the TUI's
/// `&'static ServerConfig`).
#[derive(Debug, Clone)]
pub struct Connection {
    pub address: String,
    pub user: String,
    pub password: String,
}

/// Writes bash/zsh/fish completions and a man page for `cmd` into `dir`.
/// Used by each binary's `build.rs` (architecture/cli.md D7).
pub fn generate_assets(
    mut cmd: clap::Command,
    bin_name: &str,
    dir: &std::path::Path,
) -> std::io::Result<()> {
    use clap_complete::Shell;
    std::fs::create_dir_all(dir.join("completions"))?;
    std::fs::create_dir_all(dir.join("man"))?;
    for shell in [Shell::Bash, Shell::Zsh, Shell::Fish] {
        clap_complete::generate_to(shell, &mut cmd, bin_name, dir.join("completions"))?;
    }
    let man = clap_mangen::Man::new(cmd);
    let mut out = Vec::new();
    man.render(&mut out)?;
    std::fs::write(dir.join("man").join(format!("{bin_name}.1")), out)?;
    Ok(())
}

/// Prints a completion script for `shell` to stdout (the `completions`
/// subcommand).
pub fn print_completions(shell: clap_complete::Shell, cmd: &mut clap::Command, bin_name: &str) {
    clap_complete::generate(shell, cmd, bin_name, &mut std::io::stdout());
}

#[cfg(feature = "client")]
mod client;
#[cfg(feature = "client")]
pub use client::run_remote;

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

    #[test]
    fn no_subcommand_parses_on_every_binary() {
        assert!(ServerCli::try_parse_from(["crabidy-server"])
            .expect("server")
            .command
            .is_none());
        assert!(TuiCli::try_parse_from(["cbd-tui"])
            .expect("tui")
            .command
            .is_none());
        assert!(CbdCli::try_parse_from(["cbd"])
            .expect("cbd")
            .command
            .is_none());
    }

    #[test]
    fn remote_flags_override_when_present_and_are_none_otherwise() {
        let cli = TuiCli::try_parse_from(["cbd-tui", "--address", "http://x:1", "-u", "owner"])
            .expect("parse");
        assert_eq!(cli.remote.address.as_deref(), Some("http://x:1"));
        assert_eq!(cli.remote.user.as_deref(), Some("owner"));
        assert!(cli.remote.password.is_none());

        let bare = TuiCli::try_parse_from(["cbd-tui"]).expect("bare");
        assert!(bare.remote.address.is_none());
        assert!(bare.remote.user.is_none());
    }

    #[test]
    fn library_list_defaults_to_root() {
        let cli = ServerCli::try_parse_from(["crabidy-server", "library", "list"]).expect("parse");
        match cli.command {
            Some(ServerCommand::Library(LibraryCmd::List { path })) => assert_eq!(path, "/"),
            other => panic!("unexpected: {other:?}"),
        }
        let cli = ServerCli::try_parse_from(["crabidy-server", "library", "list", "/tidal"])
            .expect("parse");
        match cli.command {
            Some(ServerCommand::Library(LibraryCmd::List { path })) => assert_eq!(path, "/tidal"),
            other => panic!("unexpected: {other:?}"),
        }
    }

    #[test]
    fn queue_append_collects_many_paths() {
        let cli = TuiCli::try_parse_from(["cbd-tui", "queue", "append", "/a", "/b", "/c"])
            .expect("parse");
        match cli.command {
            Some(TuiCommand::Queue(QueueCmd::Append { paths })) => {
                assert_eq!(paths, vec!["/a", "/b", "/c"]);
            }
            other => panic!("unexpected: {other:?}"),
        }
    }

    #[test]
    fn queue_clear_keep_current_is_a_flag() {
        let cli =
            TuiCli::try_parse_from(["cbd-tui", "queue", "clear", "--keep-current"]).expect("parse");
        match cli.command {
            Some(TuiCommand::Queue(QueueCmd::Clear { keep_current })) => assert!(keep_current),
            other => panic!("unexpected: {other:?}"),
        }
    }

    #[test]
    fn global_volume_parses_a_signed_delta() {
        let cli =
            TuiCli::try_parse_from(["cbd-tui", "global", "volume", "--", "-0.1"]).expect("parse");
        match cli.command {
            Some(TuiCommand::Global(GlobalCmd::Volume { delta })) => {
                assert!((delta - -0.1).abs() < f32::EPSILON);
            }
            other => panic!("unexpected: {other:?}"),
        }
    }

    #[test]
    fn guard_reads_a_role_and_optional_password() {
        let cli = ServerCli::try_parse_from(["crabidy-server", "guard", "owner"]).expect("parse");
        match cli.command {
            Some(ServerCommand::Guard(args)) => {
                assert_eq!(args.role, Role::Owner);
                assert!(args.password.is_none());
                assert!(!args.no_config);
            }
            other => panic!("unexpected: {other:?}"),
        }
        let cli = ServerCli::try_parse_from([
            "crabidy-server",
            "guard",
            "queue-owner",
            "secret",
            "--no-config",
        ])
        .expect("parse");
        match cli.command {
            Some(ServerCommand::Guard(args)) => {
                assert_eq!(args.role, Role::QueueOwner);
                assert_eq!(args.password.as_deref(), Some("secret"));
                assert!(args.no_config);
            }
            other => panic!("unexpected: {other:?}"),
        }
    }

    #[test]
    fn scan_flags_parse() {
        let cli = ServerCli::try_parse_from(["crabidy-server", "scan", "/music", "--capture"])
            .expect("p");
        match cli.command {
            Some(ServerCommand::Scan(args)) => {
                assert_eq!(args.path, std::path::PathBuf::from("/music"));
                assert!(args.capture);
                assert!(!args.move_);
            }
            other => panic!("unexpected: {other:?}"),
        }
    }

    #[test]
    fn cbd_is_the_union_of_server_and_client_commands() {
        assert!(matches!(
            CbdCli::try_parse_from(["cbd", "guard", "owner"])
                .expect("p")
                .command,
            Some(CbdCommand::Guard(_))
        ));
        assert!(matches!(
            CbdCli::try_parse_from(["cbd", "auth", "owner", "pw"])
                .expect("p")
                .command,
            Some(CbdCommand::Auth(_))
        ));
        assert!(matches!(
            CbdCli::try_parse_from(["cbd", "global", "play"])
                .expect("p")
                .command,
            Some(CbdCommand::Global(GlobalCmd::Play))
        ));
    }
}