import os
import networkx as nx

def get_imports(path):
    imports = []
    try:
        with open(path, 'r') as f:
            lines = f.readlines()
        in_imports = False
        for line in lines:
            stripped = line.strip()
            if stripped == "imports:":
                in_imports = True
                continue
            if in_imports:
                if not stripped.startswith("-"):
                    if stripped and not stripped.startswith("#"):
                        in_imports = False
                else:
                    imp = stripped.lstrip("- ").strip()
                    imports.append(imp)
    except Exception:
        pass
    return imports

def build_graph(root_dir):
    G = nx.DiGraph()
    
    # Map file paths to node names
    # Node name: relative path from root_dir or filename if unique
    # LinkML imports are relative paths.
    
    # We need to resolve relative paths.
    
    # files: list of (abs_path, rel_path_from_root)
    # root_dir is schemas/20251121/linkml
    
    files_map = {} # abs_path -> rel_path
    
    for root, dirs, files in os.walk(root_dir):
        for file in files:
            if file.endswith(".yaml"):
                abs_path = os.path.join(root, file)
                rel_path = os.path.relpath(abs_path, root_dir)
                files_map[abs_path] = rel_path
                G.add_node(rel_path)
                
    for abs_path, rel_path in files_map.items():
        imports = get_imports(abs_path)
        base_dir = os.path.dirname(abs_path)
        
        for imp in imports:
            # imp is relative to abs_path
            # resolve it
            if imp.startswith("linkml:"):
                continue
                
            imp_abs = os.path.normpath(os.path.join(base_dir, imp))
            if not imp_abs.endswith(".yaml"):
                 imp_abs += ".yaml"
            
            if imp_abs in files_map:
                target = files_map[imp_abs]
                G.add_edge(rel_path, target)
            else:
                # print(f"Warning: {rel_path} imports {imp} which resolves to {imp_abs} (not found)")
                pass

    return G

def find_cycles(G):
    try:
        cycles = nx.simple_cycles(G)
        count = 0
        for cycle in cycles:
            print("Cycle found:")
            print(cycle)
            count += 1
            if count >= 10:
                print("Stopping after 10 cycles.")
                break
        if count == 0:
            print("No cycles found.")
    except Exception as e:
        print(f"Error finding cycles: {e}")

if __name__ == "__main__":
    G = build_graph("schemas/20251121/linkml")
    find_cycles(G)