//! sylpheed-cli — command line tools for Project Sylpheed asset work.
//!
//! ## Commands
//!
//! ### Extract an ISO
//! ```bash
//! sylpheed-cli extract game.iso ./assets/
//! ```
//!
//! ### List files inside an ISO
//! ```bash
//! sylpheed-cli list game.iso
//! sylpheed-cli list game.iso --filter .xpr
//! ```
//!
//! ### Sniff the format of unknown files
//! ```bash
//! sylpheed-cli sniff ./assets/DATA/
//! ```
//! Walks a directory and prints the magic-byte-identified type of each file.
//! Invaluable for the first pass of reverse engineering.
//!
//! ### Inspect a texture
//! ```bash
//! sylpheed-cli texture info ./assets/DATA/TEXTURES/SHIP01.XPR
//! sylpheed-cli texture export ./assets/DATA/TEXTURES/SHIP01.XPR ship01.png
//! ```
//!
//! ### Inspect IPFB archives and IDXD definitions
//! ```bash
//! sylpheed-cli pak list ./assets/dat/GP_MAIN_GAME_E.pak            # inventory entries
//! sylpheed-cli pak dump ./assets/dat/GP_MAIN_GAME_E.pak 0x7c96296c # one object's stat sheet
//! ```

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

use anyhow::{Context, Result};
use clap::{Parser, Subcommand};
use colored::*;
use indicatif::{ProgressBar, ProgressStyle};
use tracing::info;

use sylpheed_formats::vfs::{identify_format, GameAssets};
use sylpheed_formats::{IdxdObject, PakArchive};

// ── CLI definition ─────────────────────────────────────────────────────────

#[derive(Parser)]
#[command(
    name = "sylpheed-cli",
    about = "Project Sylpheed: Arc of Deception — asset tools",
    version,
    long_about = None,
)]
struct Cli {
    #[command(subcommand)]
    command: Commands,
}

#[derive(Subcommand)]
enum Commands {
    /// Extract all files from an XISO disc image
    Extract {
        /// Path to the .iso file
        iso: PathBuf,
        /// Output directory (will be created if it doesn't exist)
        output: PathBuf,
    },

    /// List files inside an XISO disc image
    List {
        /// Path to the .iso file
        iso: PathBuf,
        /// Only show files matching this substring
        #[arg(long)]
        filter: Option<String>,
    },

    /// Walk a directory and identify file formats by magic bytes.
    /// Essential for the first pass of reverse engineering.
    Sniff {
        /// Directory to walk (use your extraction output)
        dir: PathBuf,
        /// Only show unrecognized files (focus RE effort)
        #[arg(long)]
        unknown_only: bool,
    },

    /// Texture tools
    Texture {
        #[command(subcommand)]
        cmd: TextureCommands,
    },

    /// IPFB archive (`*.pak`) and IDXD definition tools
    Pak {
        #[command(subcommand)]
        cmd: PakCommands,
    },
}

#[derive(Subcommand)]
enum PakCommands {
    /// List the entries of an IPFB archive (hash, size, inner format, identity)
    List {
        /// Path to the `.pak` index (sibling `.p00`/`.pNN` segments are loaded automatically)
        pak: PathBuf,
        /// Only show IDXD-object entries
        #[arg(long)]
        idxd_only: bool,
    },
    /// Dump one entry: its IDXD schema and every explicitly-valued field
    Dump {
        /// Path to the `.pak` index
        pak: PathBuf,
        /// Entry name-hash, e.g. `0x7c96296c`
        hash: String,
    },
}

#[derive(Subcommand)]
enum TextureCommands {
    /// Print information about a texture file
    Info {
        /// Path to the texture file
        file: PathBuf,
    },
    /// Export a texture to PNG
    Export {
        /// Path to the texture file
        file: PathBuf,
        /// Output PNG path
        output: PathBuf,
    },
}

// ── Entry point ────────────────────────────────────────────────────────────

#[tokio::main]
async fn main() -> Result<()> {
    tracing_subscriber::fmt()
        .with_env_filter(
            tracing_subscriber::EnvFilter::from_default_env()
                .add_directive("sylpheed=info".parse().unwrap())
        )
        .init();

    let cli = Cli::parse();

    match cli.command {
        Commands::Extract { iso, output } => cmd_extract(&iso, &output).await,
        Commands::List { iso, filter }    => cmd_list(&iso, filter).await,
        Commands::Sniff { dir, unknown_only } => cmd_sniff(&dir, unknown_only),
        Commands::Texture { cmd } => match cmd {
            TextureCommands::Info { file }           => cmd_texture_info(&file),
            TextureCommands::Export { file, output } => cmd_texture_export(&file, &output),
        },
        Commands::Pak { cmd } => match cmd {
            PakCommands::List { pak, idxd_only } => cmd_pak_list(&pak, idxd_only),
            PakCommands::Dump { pak, hash }      => cmd_pak_dump(&pak, &hash),
        },
    }
}

// ── extract ────────────────────────────────────────────────────────────────

async fn cmd_extract(iso_path: &Path, output_dir: &Path) -> Result<()> {
    println!(
        "{} {} → {}",
        "Extracting".green().bold(),
        iso_path.display().to_string().cyan(),
        output_dir.display().to_string().cyan()
    );

    let mut reader = sylpheed_formats::xiso::open_iso(iso_path).await?;

    // Count files first for a meaningful progress bar
    println!("{} Scanning ISO contents...", "  ·".dimmed());
    let all_files = reader.list_all_files().await?;
    let total = all_files.len();
    println!("  Found {} files", total.to_string().yellow());

    let pb = ProgressBar::new(total as u64);
    pb.set_style(
        ProgressStyle::default_bar()
            .template("{spinner:.cyan} [{bar:40.cyan/blue}] {pos}/{len} {msg}")
            .unwrap()
            .progress_chars("█▉▊▋▌▍▎▏  ")
    );

    let stats = reader.extract_all(output_dir).await?;
    pb.finish_and_clear();

    println!(
        "{} Extracted {} files ({:.2} MB)",
        "✓".green().bold(),
        stats.files_extracted.to_string().yellow(),
        (stats.bytes_extracted as f64) / (1024.0 * 1024.0)
    );
    println!(
        "  Assets ready at: {}",
        output_dir.display().to_string().cyan()
    );
    println!();
    println!(
        "  {} Run the viewer: {}",
        "→".cyan(),
        "cargo run --bin sylpheed-viewer".bold()
    );

    Ok(())
}

// ── list ───────────────────────────────────────────────────────────────────

async fn cmd_list(iso_path: &Path, filter: Option<String>) -> Result<()> {
    println!("{} {}", "Listing".green().bold(), iso_path.display().to_string().cyan());

    let mut reader = sylpheed_formats::xiso::open_iso(iso_path).await?;
    let files = reader.list_all_files().await?;

    let filter_lower = filter.as_deref().unwrap_or("").to_lowercase();

    let mut shown = 0;
    for file in &files {
        if filter_lower.is_empty() || file.to_lowercase().contains(&filter_lower) {
            println!("  {}", file);
            shown += 1;
        }
    }

    println!(
        "\n  {} files{}",
        shown.to_string().yellow(),
        if !filter_lower.is_empty() {
            format!(" (filtered from {})", files.len())
        } else {
            String::new()
        }
    );

    Ok(())
}

// ── sniff ──────────────────────────────────────────────────────────────────

fn cmd_sniff(dir: &Path, unknown_only: bool) -> Result<()> {
    println!(
        "{} {}",
        "Sniffing formats in".green().bold(),
        dir.display().to_string().cyan()
    );
    println!("{}", "  (reading magic bytes of each file)".dimmed());
    println!();

    let assets = GameAssets::from_directory(dir);
    let files = assets.list("").context("Failed to read directory")?;

    let mut counts: std::collections::HashMap<&str, usize> = std::collections::HashMap::new();

    for file in &files {
        let Ok(bytes) = assets.read(file) else { continue; };
        let fmt = identify_format(&bytes);
        let label = fmt.extension_hint();
        *counts.entry(label).or_insert(0) += 1;

        if unknown_only && label != "bin" {
            continue;
        }

        let color_label = match label {
            "bin" => label.red().to_string(),
            "xpr" => label.green().to_string(),
            "dds" => label.green().to_string(),
            "txt" => label.cyan().to_string(),
            _ => label.yellow().to_string(),
        };

        // Show first 8 bytes as hex for unknown files
        let hex_preview = if label == "bin" && bytes.len() >= 8 {
            format!(
                "  {:02X} {:02X} {:02X} {:02X} {:02X} {:02X} {:02X} {:02X}",
                bytes[0], bytes[1], bytes[2], bytes[3],
                bytes[4], bytes[5], bytes[6], bytes[7]
            ).dimmed().to_string()
        } else {
            String::new()
        };

        println!("  [{color_label}] {file}{hex_preview}");
    }

    // Summary
    println!();
    println!("{}", "Format Summary:".bold());
    let mut summary: Vec<_> = counts.into_iter().collect();
    summary.sort_by(|a, b| b.1.cmp(&a.1));
    for (fmt, count) in summary {
        println!(
            "  {:>6}  .{}",
            count.to_string().yellow(),
            fmt
        );
    }

    Ok(())
}

// ── texture info ──────────────────────────────────────────────────────────

fn cmd_texture_info(file: &Path) -> Result<()> {
    let bytes = std::fs::read(file)
        .with_context(|| format!("Cannot read {}", file.display()))?;

    use sylpheed_formats::texture::X360Texture;
    let tex = X360Texture::from_xpr2(&bytes)
        .with_context(|| format!("Failed to parse texture: {}", file.display()))?;

    println!("{} {}", "Texture:".green().bold(), file.display());
    println!("  Resolution : {}×{}", tex.width.to_string().yellow(), tex.height.to_string().yellow());
    println!("  Format     : {:?}", tex.format);
    println!("  Mip levels : {}", tex.mip_levels);
    println!("  Data size  : {} bytes", tex.data.len().to_string().yellow());

    Ok(())
}

// ── texture export ────────────────────────────────────────────────────────

fn cmd_texture_export(file: &Path, output: &Path) -> Result<()> {
    let bytes = std::fs::read(file)
        .with_context(|| format!("Cannot read {}", file.display()))?;

    use sylpheed_formats::texture::X360Texture;
    let tex = X360Texture::from_xpr2(&bytes)?;
    let rgba = decode_to_rgba8(&tex)
        .with_context(|| format!("decoding {:?} texture", tex.format))?;

    image::save_buffer(
        output,
        &rgba,
        tex.width,
        tex.height,
        image::ExtendedColorType::Rgba8,
    )
    .with_context(|| format!("writing PNG {}", output.display()))?;

    println!(
        "{} {}×{} {:?}{} → {}",
        "Exported".green().bold(),
        tex.width,
        tex.height,
        tex.format,
        if tex.is_cubemap { " (cubemap face 0)" } else { "" },
        output.display().to_string().cyan(),
    );
    Ok(())
}

/// Software-decode a de-tiled `X360Texture` (mip 0) to tightly-packed RGBA8.
///
/// BCn blocks are decompressed with `texpresso`; uncompressed A8R8G8B8/X8R8G8B8
/// is byte-swizzled from the Xenos in-memory BGRA order.
fn decode_to_rgba8(tex: &sylpheed_formats::texture::X360Texture) -> Result<Vec<u8>> {
    use sylpheed_formats::texture::X360TextureFormat as F;
    let (w, h) = (tex.width as usize, tex.height as usize);
    let mut rgba = vec![0u8; w * h * 4];

    let bc = |fmt: texpresso::Format, rgba: &mut [u8]| {
        fmt.decompress(&tex.data, w, h, rgba);
    };

    match tex.format {
        F::Dxt1 => bc(texpresso::Format::Bc1, &mut rgba),
        F::Dxt3 => bc(texpresso::Format::Bc2, &mut rgba),
        F::Dxt5 => bc(texpresso::Format::Bc3, &mut rgba),
        F::A8R8G8B8 | F::X8R8G8B8 => {
            // After the k8in32 endian swap in from_xpr2, k_8_8_8_8 pixels are in
            // [A,R,G,B] byte order (verified against the retail Acheron backdrop).
            // Emit RGBA. X8 has no meaningful alpha.
            let opaque = matches!(tex.format, F::X8R8G8B8);
            for (px, out) in tex.data.chunks_exact(4).zip(rgba.chunks_exact_mut(4)) {
                out[0] = px[1]; // R
                out[1] = px[2]; // G
                out[2] = px[3]; // B
                out[3] = if opaque { 0xFF } else { px[0] };
            }
        }
        other => {
            anyhow::bail!("PNG export for {other:?} (BC4/BC5) not implemented yet");
        }
    }
    Ok(rgba)
}

// ── pak list ────────────────────────────────────────────────────────────────

use sylpheed_formats::pak::inner_format_label as inner_label;

/// Try to recover an IDXD entry's original TOC path from its identity tokens.
/// Uses the entry's ID/Name/Model fields plus identifier-like pool tokens as
/// candidates for [`sylpheed_formats::hash::recover_toc_name`].
fn idxd_toc_name(obj: &IdxdObject, name_hash: u32) -> Option<String> {
    let mut cands: Vec<&str> = Vec::new();
    for key in ["ID", "Name", "Model"] {
        if let Some(v) = obj.get_raw(key) {
            cands.push(v);
        }
    }
    for t in obj.tokens() {
        if t.contains('_') || t.len() >= 5 {
            cands.push(t.as_str());
        }
    }
    sylpheed_formats::hash::recover_toc_name(name_hash, &cands)
}

fn cmd_pak_list(pak: &Path, idxd_only: bool) -> Result<()> {
    let arc = PakArchive::open(pak).with_context(|| format!("opening {}", pak.display()))?;
    println!(
        "{} {}  ({} entries, block 0x{:x})",
        "Archive".green().bold(),
        pak.display().to_string().cyan(),
        arc.len().to_string().yellow(),
        arc.block_size,
    );

    let mut shown = 0usize;
    let mut named = 0usize;
    for e in arc.entries() {
        let payload = match arc.read(e) {
            Ok(p) => p,
            Err(err) => {
                eprintln!("  {:08x}  <read error: {err}>", e.name_hash);
                continue;
            }
        };
        let label = inner_label(&payload);
        let is_idxd = label == "IDXD";
        if idxd_only && !is_idxd {
            continue;
        }
        let (detail, name) = if is_idxd {
            match IdxdObject::parse(&payload) {
                Ok(o) => (o.identity(), idxd_toc_name(&o, e.name_hash)),
                Err(_) => (String::new(), None),
            }
        } else {
            (String::new(), None)
        };
        let name_col = match &name {
            Some(p) => p.clone(),
            None => "?".into(),
        };
        println!(
            "  {:08x}  {:<28}  {:>9} B  {:<6}  {}",
            e.name_hash,
            name_col.green(),
            payload.len(),
            label.yellow(),
            detail.dimmed(),
        );
        if name.is_some() {
            named += 1;
        }
        shown += 1;
    }
    println!(
        "\n  {} entries shown ({} name-resolved)",
        shown.to_string().yellow(),
        named.to_string().green(),
    );
    Ok(())
}

// ── pak dump ────────────────────────────────────────────────────────────────

fn parse_hash(s: &str) -> Result<u32> {
    let t = s.trim_start_matches("0x").trim_start_matches("0X");
    u32::from_str_radix(t, 16).with_context(|| format!("invalid hex hash: {s:?}"))
}

fn cmd_pak_dump(pak: &Path, hash_str: &str) -> Result<()> {
    let hash = parse_hash(hash_str)?;
    let arc = PakArchive::open(pak).with_context(|| format!("opening {}", pak.display()))?;
    let entry = arc
        .find(hash)
        .with_context(|| format!("no entry with hash 0x{hash:08x} in {}", pak.display()))?;
    let payload = arc.read(entry)?;

    if !IdxdObject::is_idxd(&payload) {
        println!(
            "{} entry 0x{hash:08x} is {} ({} bytes) — not an IDXD object",
            "Note:".yellow(),
            inner_label(&payload),
            payload.len(),
        );
        return Ok(());
    }

    let obj = IdxdObject::parse(&payload)?;
    println!(
        "{} 0x{hash:08x}  schema 0x{:08x}  count {}",
        "IDXD".green().bold(),
        obj.schema_hash,
        obj.count,
    );
    // Identity fields — the head-of-object fields that are reliably identifier-valued.
    for key in ["ID", "Name", "Type", "Model"] {
        if let Some(v) = obj.get_raw(key) {
            println!("  {:<10} {}", format!("{key}:").dimmed(), v.cyan());
        }
    }

    let fields = obj.resolved_fields();
    println!(
        "\n  {} ({} explicit-value fields; defaulted fields omitted):",
        "Fields".bold(),
        fields.len().to_string().yellow(),
    );
    for (key, val) in &fields {
        println!("    {:<28} = {}", key, val.yellow());
    }
    Ok(())
}