//! The `spectra` command line (spec §19). Output follows `oxy`: colour and
//! glyphs on a UTF-8 terminal, plain when piped, with `--plain` or with
//! `NO_COLOR`; `--json` prints one document on stdout and nothing else.

pub mod admin;
pub mod format;
pub mod json;
pub mod ui;

use anyhow::{bail, Result};
use clap::{Parser, Subcommand};
use std::path::PathBuf;

#[derive(Parser)]
#[command(name = "spectra", version = env!("SPECTRA_VERSION_LONG"), about = "A control plane for AI coding agents")]
pub struct Cli {
    /// Plain output: no colour or glyphs (also NO_COLOR, or when not a terminal)
    #[arg(long, global = true)]
    pub plain: bool,
    /// The data directory (default: $XDG_DATA_HOME/spectra, else ~/.local/share/spectra)
    #[arg(long, global = true, env = "SPECTRA_DATA")]
    pub data: Option<PathBuf>,
    #[command(subcommand)]
    pub command: Command,
}

#[derive(Subcommand)]
pub enum Command {
    /// The version and build of this binary
    Version {
        /// Machine-readable output
        #[arg(long)]
        json: bool,
    },
    /// The ledger's own checks: verify, check, rebuild
    Admin {
        #[command(subcommand)]
        command: Admin,
    },
}

#[derive(Subcommand)]
pub enum Admin {
    /// Recompute the hash chain and check every checkpoint and proof (exit 1 on any finding)
    Verify {
        /// Machine-readable output
        #[arg(long)]
        json: bool,
    },
    /// Whether the projections equal a rebuild from the ledger
    Check,
    /// Replay the ledger into every projection
    Rebuild,
}

/// What every command needs: where the data lives.
pub struct Ctx {
    pub data: PathBuf,
}

impl Ctx {
    /// The ledger's database, which must exist.
    pub fn db(&self) -> Result<PathBuf> {
        let db = self.data.join("spectra.db");
        if !db.exists() {
            bail!("no Spectra in {} (run `spectra init`, or pass --data)", self.data.display());
        }
        Ok(db)
    }
}

fn default_data() -> PathBuf {
    if let Ok(x) = std::env::var("XDG_DATA_HOME") {
        return PathBuf::from(x).join("spectra");
    }
    let home = std::env::var("HOME").unwrap_or_else(|_| ".".into());
    PathBuf::from(home).join(".local").join("share").join("spectra")
}

fn runtime() -> Result<tokio::runtime::Runtime> {
    Ok(tokio::runtime::Builder::new_multi_thread().enable_all().build()?)
}

pub fn run() -> Result<i32> {
    let cli = Cli::parse();
    ui::init(cli.plain);
    let ctx = Ctx { data: cli.data.unwrap_or_else(default_data) };
    match cli.command {
        Command::Version { json } => version(json),
        Command::Admin { command } => runtime()?.block_on(async {
            match command {
                Admin::Verify { json } => admin::verify(&ctx, json).await,
                Admin::Check => admin::check(&ctx).await,
                Admin::Rebuild => admin::rebuild(&ctx).await,
            }
        }),
    }
}

fn version(as_json: bool) -> Result<i32> {
    if as_json {
        println!(
            "{}",
            serde_json::json!({
                "version": env!("CARGO_PKG_VERSION"),
                "build": env!("SPECTRA_BUILD_ID"),
                "mcp_protocol_versions": spectra_mcp::PROTOCOL_VERSIONS,
                "ledger_format": spectra_core::LEDGER_FORMAT,
            })
        );
    } else {
        println!("spectra {}", env!("SPECTRA_VERSION_LONG"));
    }
    Ok(0)
}