use anyhow::Context;

use crate::adapters::Device;

use super::registry::{AdapterRegistry, DeviceRegistry};

/// Background discovery orchestration for supported TV platforms.
#[derive(Debug, Clone)]
pub struct DiscoveryService {
    adapters: AdapterRegistry,
}

impl DiscoveryService {
    /// Create a discovery service over the registered adapters.
    pub fn new(adapters: AdapterRegistry) -> Self {
        Self { adapters }
    }

    /// Discover all supported platforms and merge them into the registry.
    pub async fn discover_all(&self, registry: &mut DeviceRegistry) -> anyhow::Result<Vec<Device>> {
        let mut discovered = Vec::new();
        for platform in self.adapters.supported_platforms() {
            let mut devices = self
                .discover_platform(platform, registry)
                .await
                .with_context(|| format!("failed discovery for platform '{platform}'"))?;
            discovered.append(&mut devices);
        }
        Ok(discovered)
    }

    /// Discover one platform and merge the results into the registry.
    pub async fn discover_platform(
        &self,
        platform: &str,
        registry: &mut DeviceRegistry,
    ) -> anyhow::Result<Vec<Device>> {
        let discovered = self.adapters.discover(platform).await?;
        Ok(registry.merge_discovered(discovered))
    }
}