use opentelemetry_otlp::{LogExporter, WithExportConfig, WithHttpConfig};
use opentelemetry_sdk::Resource;
use opentelemetry_sdk::logs::SdkLoggerProvider;

use crate::config::TelemetryConfig;

pub fn build(
    config: &TelemetryConfig,
    resource: Resource,
    warnings: &mut Vec<String>,
) -> SdkLoggerProvider {
    let mut builder = SdkLoggerProvider::builder().with_resource(resource);

    if let Some(endpoint) = config.logs_url() {
        match exporter(config, &endpoint) {
            Ok(exporter) => builder = builder.with_batch_exporter(exporter),
            Err(error) => warnings.push(format!(
                "otlp log exporter disabled: {error} (endpoint {endpoint})"
            )),
        }
    }

    builder.build()
}

fn exporter(
    config: &TelemetryConfig,
    endpoint: &str,
) -> Result<LogExporter, opentelemetry_otlp::ExporterBuildError> {
    let mut builder = LogExporter::builder()
        .with_http()
        .with_endpoint(endpoint)
        .with_timeout(config.timeout);
    if !config.logs.headers.is_empty() {
        builder = builder.with_headers(config.logs.headers.clone());
    }
    builder.build()
}