Method _load_existing_code_graph

rust-core/src/codegraph/parser.rs:819–878

尝试从本地数据库加载现有的CodeGraph

(&self, dir: &Path)

    /// 尝试从本地数据库加载现有的CodeGraph
    fn _load_existing_code_graph(&self, dir: &Path) -> Result<Option<CodeGraph>, String> {
        use crate::storage::PersistenceManager;
        use md5;
        
        let persistence = PersistenceManager::new();
        
        // 尝试多种方式的项目ID
        let project_ids = vec![
            // 1. 使用目录名（原始方式）
            dir.file_name()
                .and_then(|n| n.to_str())
                .unwrap_or("default")
                .to_string(),
            // 2. 使用目录路径的MD5哈希（HTTP接口方式）
            format!("{:x}", md5::compute(dir.to_string_lossy().as_bytes())),
        ];
        
        for project_id in project_ids {
            info!("Attempting to load existing CodeGraph for project ID: {}", project_id);
            
            match persistence.load_graph(&project_id) {
                Ok(Some(pet_graph)) => {
                    info!("Found existing PetCodeGraph with {} functions for project ID: {}", 
                          pet_graph.graph.node_count(), project_id);
                    
                    // 将PetCodeGraph转换为CodeGraph
                    let mut code_graph = CodeGraph::new();
                    
                    // 添加所有函数
                    let mut function_count = 0;
                    for function in pet_graph.graph.node_weights() {
                        code_graph.add_function(function.clone());
                        function_count += 1;
                    }
                    info!("Converted {} functions from PetCodeGraph to CodeGraph", function_count);
                    
                    // 添加所有调用关系
                    let mut relation_count = 0;
                    for edge in pet_graph.graph.edge_weights() {
                        code_graph.add_call_relation(edge.clone());
                        relation_count += 1;
                    }
                    info!("Converted {} call relations from PetCodeGraph to CodeGraph", relation_count);
                    
                    return Ok(Some(code_graph));
                },
                Ok(None) => {
                    info!("No existing graph found for project ID: {}", project_id);
                    continue;
                },
                Err(e) => {
                    warn!("Failed to load existing CodeGraph for project ID {}: {}", project_id, e);
                    continue;
                }
            }
        }
        
        info!("No existing graph found for any project ID");