use std::{env, fs::{self, read_dir}, io::Write, path::PathBuf};

use zip::{write::SimpleFileOptions, ZipWriter};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    tauri_build::build();

    let out_dir = PathBuf::from(env::var("OUT_DIR")?);

    let profile_target_dir = out_dir
        .ancestors()
        .nth(3)
        .ok_or("Failed to determine profile target directory from OUT_DIR")?;

    println!(
        "cargo:info=Build script running for target OS: {}",
        env::var("CARGO_CFG_TARGET_OS").unwrap_or_default()
    );
    println!(
        "cargo:info=Final libraries will be copied to: {}",
        profile_target_dir.display()
    );

    // --- Define libraries and their source locations based on OS ---
    let target_os = env::var("CARGO_CFG_TARGET_OS")?;

    let source_subdir = if target_os == "windows" {
        "lib/win64"
    } else if target_os == "linux" {
        "lib/linux64"
    } else if target_os == "macos" {
        "lib/osx"
    } else {
        return Err("Unsupported target".into());
    };

    for f in read_dir(source_subdir)? {
        let f = f?;
        println!("cargo:rerun-if-changed={}", f.path().display());
        fs::copy(f.path(), profile_target_dir.join(f.file_name()))?;
    }

    // Build data file
    println!("cargo:rerun-if-changed=src/cursors");
    println!("cargo:rerun-if-changed=src/cursor_def.json");

    let mut zip = ZipWriter::new(fs::OpenOptions::new().write(true).create(true).open(profile_target_dir.join("cursor_rush.dat"))?);
    zip.start_file("cursor_def.json", SimpleFileOptions::default())?;
    zip.write_all(&fs::read("src/cursor_def.json")?)?;

    for f in read_dir("src/cursors")? {
      let f = f?;
      zip.start_file(f.file_name().to_string_lossy(), SimpleFileOptions::default())?;
      zip.write_all(&fs::read(f.path())?)?;
    }

    zip.finish()?;
    

    Ok(())
}