// Copyright (c) Microsoft Corporation.
// Licensed under the MIT License.

//! Splits debug info from a binary into a separate file using `objcopy`

use crate::run_cargo_build::common::CommonArch;
use flowey::node::prelude::*;

flowey_request! {
    pub struct Request {
        pub arch: CommonArch,
        pub in_bin: ReadVar<PathBuf>,
        pub out_bin: WriteVar<PathBuf>,
        pub out_dbg_info: WriteVar<PathBuf>,
    }
}

new_simple_flow_node!(struct Node);

impl SimpleFlowNode for Node {
    type Request = Request;

    fn imports(ctx: &mut ImportCtx<'_>) {
        ctx.import::<flowey_lib_common::install_dist_pkg::Node>();
    }

    fn process_request(request: Self::Request, ctx: &mut NodeCtx<'_>) -> anyhow::Result<()> {
        let Request {
            arch,
            in_bin,
            out_bin,
            out_dbg_info,
        } = request;

        let platform = ctx.platform();
        let arch_str = match arch {
            CommonArch::X86_64 => match platform {
                FlowPlatform::Linux(linux_distribution) => match linux_distribution {
                    FlowPlatformLinuxDistro::Fedora => "x86_64",
                    FlowPlatformLinuxDistro::Ubuntu => "x86-64",
                    FlowPlatformLinuxDistro::Unknown => anyhow::bail!("Unknown Linux distribution"),
                },
                _ => anyhow::bail!("Unsupported platform"),
            },
            CommonArch::Aarch64 => "aarch64",
        };

        let installed_objcopy =
            ctx.reqv(
                |side_effect| flowey_lib_common::install_dist_pkg::Request::Install {
                    package_names: vec![format!("binutils-{arch_str}-linux-gnu")],
                    done: side_effect,
                },
            );

        ctx.emit_rust_step("split debug symbols", |ctx| {
            installed_objcopy.clone().claim(ctx);
            let in_bin = in_bin.claim(ctx);
            let out_bin = out_bin.claim(ctx);
            let out_dbg_info = out_dbg_info.claim(ctx);
            move |rt| {
                let in_bin = rt.read(in_bin);

                let sh = xshell::Shell::new()?;
                let output = sh.current_dir().join(in_bin.file_name().unwrap());
                let objcopy = format!("{}-linux-gnu-objcopy", arch.as_arch());
                xshell::cmd!(sh, "{objcopy} --only-keep-debug {in_bin} {output}.dbg").run()?;
                xshell::cmd!(
                    sh,
                    "{objcopy} --strip-all --keep-section=.build_info --add-gnu-debuglink={output}.dbg {in_bin} {output}"
                )
                .run()?;

                let output = output.absolute()?;

                rt.write(out_bin, &output);
                rt.write(out_dbg_info, &output.with_extension("dbg"));

                Ok(())
            }
        });

        Ok(())
    }
}
