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use fidl::unpersist;
use fidl_cf_sc_internal_starnixrunnerconfig::Config as FidlConfig;
use fuchsia_inspect::Node;
use fuchsia_runtime::{take_startup_handle, HandleInfo, HandleType};
use fuchsia_zircon as zx;
#[derive(Debug)]
pub struct Config {
    pub enable_data_collection: bool,
}
impl Config {
    pub fn take_from_startup_handle() -> Self {
        let config_vmo: zx::Vmo =
            take_startup_handle(HandleInfo::new(HandleType::ComponentConfigVmo, 0))
                .expect("Config VMO handle must be provided and cannot already have been taken.")
                .into();
        let config_size =
            config_vmo.get_content_size().expect("must be able to read config vmo content size");
        assert_ne!(config_size, 0, "config vmo must be non-empty");
        let mut config_bytes = Vec::new();
        config_bytes.resize(config_size as usize, 0);
        config_vmo.read(&mut config_bytes, 0).expect("must be able to read config vmo");
        let checksum_length = u16::from_le_bytes([config_bytes[0], config_bytes[1]]) as usize;
        let fidl_start = 2 + checksum_length;
        let observed_checksum = &config_bytes[2..fidl_start];
        let expected_checksum = vec![
            0x1e, 0xf2, 0x18, 0x1c, 0x32, 0x07, 0xb2, 0x34, 0xae, 0xea, 0xc0, 0x13, 0x3a, 0x47,
            0x4d, 0xbc, 0x6f, 0xb2, 0xb0, 0x7c, 0x8f, 0x91, 0x36, 0x50, 0xfa, 0x33, 0x40, 0x89,
            0xcc, 0x80, 0x7e, 0xeb,
        ];
        assert_eq!(
            observed_checksum, expected_checksum,
            "checksum from config VMO does not match expected checksum"
        );
        let fidl_config: FidlConfig = unpersist(&config_bytes[fidl_start..])
            .expect("must be able to parse bytes as config FIDL");
        Self { enable_data_collection: fidl_config.enable_data_collection }
    }
    pub fn record_inspect(&self, inspector_node: &Node) {
        inspector_node.record_bool("enable_data_collection", self.enable_data_collection);
    }
}