tairitsu-web 0.5.5

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

fn main() {
    println!("cargo:rerun-if-changed=Cargo.toml");

    let manifest_dir =
        PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap_or_else(|_| ".".to_string()));
    let cargo_toml = manifest_dir.join("Cargo.toml");

    let output_dir = resolve_output_dir(&cargo_toml)
        .unwrap_or_else(|| PathBuf::from("../../target/tairitsu-dist"));

    let resolved = if output_dir.is_absolute() {
        output_dir
    } else {
        manifest_dir.join(output_dir)
    };

    println!("cargo:rustc-env=TAIRITSU_DIST_DIR={}", resolved.display());

    resolve_wit_path(&manifest_dir);
}

/// Locate the composed WIT directory and generate `wit_bindings_generated.rs` in
/// `$OUT_DIR`. The generated file contains a `wit_bindgen::generate!` invocation
/// with the correct absolute path, so it works both in the monorepo and when
/// `tairitsu-web` is consumed from crates.io.
///
/// Resolution order:
/// 1. `DEP_TAIRITSU_BROWSER_WORLDS_WIT_COMPOSED_DIR` (set by `tairitsu-browser-worlds` build.rs
///    via `cargo:wit_composed_dir` — available when `links = "tairitsu-browser-worlds"` is set)
/// 2. Monorepo fallback: `../browser-worlds/wit/composed` (for in-tree development)
fn resolve_wit_path(manifest_dir: &Path) {
    let out_dir = PathBuf::from(std::env::var("OUT_DIR").unwrap_or_else(|_| ".".to_string()));

    let wit_composed_dir =
        if let Ok(dir) = std::env::var("DEP_TAIRITSU_BROWSER_WORLDS_WIT_COMPOSED_DIR") {
            PathBuf::from(dir)
        } else {
            let monorepo_path = manifest_dir.join("../browser-worlds/wit/composed");
            if monorepo_path.exists() {
                monorepo_path
            } else {
                eprintln!(
                "[tairitsu-web] Warning: Could not locate browser-worlds WIT composed directory. \
                 wit-bindings feature may not compile."
            );
                return;
            }
        };

    let escaped_path = wit_composed_dir.to_string_lossy().replace('\\', "\\\\");

    let bindings_code = format!(
        r#"wit_bindgen::generate!({{
    path: "{escaped_path}",
    world: "browser-full",
}});"#
    );

    let dest = out_dir.join("wit_bindings_generated.rs");
    if let Err(e) = fs::write(&dest, &bindings_code) {
        eprintln!("[tairitsu-web] Warning: Failed to write generated WIT bindings file: {e}");
    }
}

fn resolve_output_dir(cargo_toml: &PathBuf) -> Option<PathBuf> {
    let content = fs::read_to_string(cargo_toml).ok()?;
    let manifest: toml::Value = toml::from_str(&content).ok()?;

    let output_dir = manifest
        .get("package")?
        .get("metadata")?
        .get("tairitsu")?
        .get("build")?
        .get("output_dir")
        .or_else(|| {
            manifest
                .get("package")?
                .get("metadata")?
                .get("tairitsu")?
                .get("build")?
                .get("output-dir")
        })?
        .as_str()?;

    Some(PathBuf::from(output_dir))
}