/**
 * Basic usage example for Implexus
 * 
 * This example demonstrates the unified API facade that allows
 * applications to seamlessly switch between embedded and remote modes.
 * 
 * Features demonstrated:
 * - Mode selection (embedded vs remote)
 * - Entity creation (Container, Document, Category, Index)
 * - Property management
 * - Path-based access
 * - Transactions
 * - Querying by type and expression
 * - Entity deletion
 * 
 * Note: All I/O operations are async. This example uses MainLoop
 * to run async operations from the synchronous main() function.
 */
using Implexus;
using Implexus.Core;
using Implexus.Engine;

// Global engine reference for async operations
Core.Engine engine;

public static int main(string[] args) {
    print("Implexus Basic Usage Example\n");
    print("=============================\n\n");
    
    // Parse command line arguments to select mode
    bool use_remote = false;
    string host = "localhost";
    uint16 port = 9876;
    string storage_path = "./example_data";
    
    for (int i = 1; i < args.length; i++) {
        if (args[i] == "--remote") {
            use_remote = true;
        } else if (args[i] == "--host" && i + 1 < args.length) {
            host = args[++i];
        } else if (args[i] == "--port" && i + 1 < args.length) {
            port = (uint16) int.parse(args[++i]);
        } else if (args[i] == "--path" && i + 1 < args.length) {
            storage_path = args[++i];
        } else if (args[i] == "--help") {
            print("Usage: basicusage [OPTIONS]\n");
            print("Options:\n");
            print("  --remote         Use remote mode (default: embedded)\n");
            print("  --host HOST      Remote server host (default: localhost)\n");
            print("  --port PORT      Remote server port (default: 9876)\n");
            print("  --path PATH      Storage path for embedded mode (default: ./example_data)\n");
            print("  --help           Show this help message\n");
            return 0;
        }
    }
    
    // Run the async example
    var loop = new MainLoop();
    int result = 0;
    Error? error = null;
    
    run_example.begin(use_remote, host, port, storage_path, (obj, res) => {
        try {
            result = run_example.end(res);
        } catch (Error e) {
            error = e;
            result = 1;
        }
        loop.quit();
    });
    loop.run();
    
    if (error != null) {
        stderr.printf("Error: %s\n", ((!)error).message);
    }
    
    return result;
}

async int run_example(bool use_remote, string host, uint16 port, string storage_path) throws Error {
    // ============================================================
    // MODE SELECTION
    // The only difference between modes is how you create the configuration!
    // ============================================================
    
    EngineConfiguration config;
    if (use_remote) {
        print("Mode: REMOTE (%s:%u)\n\n", host, port);
        config = EngineConfiguration.remote(host, port);
    } else {
        print("Mode: EMBEDDED (path: %s)\n\n", storage_path);
        config = EngineConfiguration.embedded(storage_path);
    }
    
    // Create the engine - same API regardless of mode
    engine = EngineFactory.create(config);
    
    print("Engine created successfully!\n\n");
    
    // ============================================================
    // WORKING WITH CONTAINERS AND DOCUMENTS
    // ============================================================
    
    print("--- Creating Containers and Documents ---\n");
    
    // Get the root container (always exists)
    var root = yield engine.get_root_async();
    print("Got root entity: %s\n", root.path.to_string());
    
    // Create a container hierarchy for organizing users
    var users = yield root.create_container_async("users");
    print("Created container: %s\n", users.path.to_string());
    
    // Create documents with type labels for querying
    var john = yield users.create_document_async("john", "User");
    print("Created document: %s (type: %s)\n", john.path.to_string(), john.type_label);
    
    // Set various property types on the document
    yield john.set_entity_property_async("email", new Invercargill.NativeElement<string>("john@example.com"));
    yield john.set_entity_property_async("age", new Invercargill.NativeElement<int>(30));
    yield john.set_entity_property_async("active", new Invercargill.NativeElement<bool?>(true));
    print("Set properties: email, age, active\n\n");
    
    // ============================================================
    // QUERYING ENTITIES
    // ============================================================
    
    print("--- Querying Entities ---\n");
    
    // Query by type label
    print("Users (by type 'User'):\n");
    foreach (var entity in yield engine.query_by_type_async("User")) {
        print("  - %s\n", entity.name);
        
        // Access properties
        var email = yield entity.get_entity_property_async("email");
        if (email != null) {
            print("    email: %s\n", ((!) email).to_string());
        }
    }
    print("\n");
    
    // Query by expression (using Invercargill.Expressions)
    print("Active users (expression 'active==true'):\n");
    foreach (var entity in yield engine.query_by_expression_async("User", "active==true")) {
        print("  - %s\n", entity.name);
    }
    print("\n");
    
    // ============================================================
    // PATH-BASED ACCESS
    // ============================================================
    
    print("--- Path-Based Access ---\n");
    
    // Access entity by path
    var path = new EntityPath("/users/john");
    var entity = yield engine.get_entity_async(path);
    print("Retrieved entity by path: %s\n", entity.path.to_string());
    
    // Check if entity exists
    var exists = yield engine.entity_exists_async(new EntityPath("/users/john"));
    print("Entity /users/john exists: %s\n".printf(exists ? "true" : "false"));
    
    var not_exists = yield engine.entity_exists_async(new EntityPath("/users/jane"));
    print("Entity /users/jane exists: %s\n".printf(not_exists ? "true" : "false"));
    print("\n");
    
    // ============================================================
    // TRANSACTIONS
    // ============================================================
    
    print("--- Transactions ---\n");
    
    // Create multiple entities atomically in a transaction
    var tx = yield engine.begin_transaction_async();
    print("Transaction started\n");
    
    try {
        var jane = yield users.create_document_async("jane", "User");
        yield jane.set_entity_property_async("email", new Invercargill.NativeElement<string>("jane@example.com"));
        yield jane.set_entity_property_async("age", new Invercargill.NativeElement<int>(25));
        yield jane.set_entity_property_async("active", new Invercargill.NativeElement<bool?>(true));
        print("Created jane in transaction\n");
        
        var bob = yield users.create_document_async("bob", "User");
        yield bob.set_entity_property_async("email", new Invercargill.NativeElement<string>("bob@example.com"));
        yield bob.set_entity_property_async("age", new Invercargill.NativeElement<int>(35));
        yield bob.set_entity_property_async("active", new Invercargill.NativeElement<bool?>(false));
        print("Created bob in transaction\n");
        
        yield tx.commit_async();
        print("Transaction committed!\n\n");
        
    } catch (Error e) {
        yield tx.rollback_async();
        print("Transaction rolled back: %s\n", e.message);
    }
    
    // ============================================================
    // CATEGORIES (Dynamic Grouping)
    // ============================================================
    
    print("--- Categories (Dynamic Grouping) ---\n");
    
    // Create a category that auto-populates with matching entities
    var active_users = yield root.create_category_async("active_users", "User", "active==true");
    print("Created category: %s\n", active_users.path.to_string());
    print("  Type filter: User\n");
    print("  Expression: active==true\n");
    
    // The category's children are automatically populated
    // with documents matching the expression
    print("  Active users in category:\n");
    foreach (var child in yield active_users.get_children_async()) {
        print("    - %s\n", child.name);
    }
    print("\n");
    
    // ============================================================
    // INDEXES (Text Search)
    // ============================================================
    
    print("--- Indexes (Text Search) ---\n");
    
    // Create an index for text search results
    // Parameters: name, type_label, expression
    var search_index = yield root.create_index_async("email_search", "User", "email");
    print("Created index: %s\n", search_index.path.to_string());
    print("  Type filter: User\n");
    print("  Expression: email\n");
    
    // Index contains documents matching the search terms
    print("  Documents in index:\n");
    foreach (var result in yield search_index.get_children_async()) {
        print("    - %s\n", result.name);
    }
    print("\n");
    
    // ============================================================
    // FINAL STATE
    // ============================================================
    
    print("--- Final State ---\n");
    print("All users:\n");
    foreach (var user in yield engine.query_by_type_async("User")) {
        var user_email = yield user.get_entity_property_async("email");
        var age = yield user.get_entity_property_async("age");
        var active = yield user.get_entity_property_async("active");
        print("  - %s (email: %s, age: %s, active: %s)\n",
            user.name,
            user_email != null ? ((!) user_email).to_string() : "N/A",
            age != null ? ((!) age).to_string() : "N/A",
            active != null ? ((!) active).to_string() : "N/A"
        );
    }
    print("\n");
    
    // ============================================================
    // CLEANUP (Optional)
    // ============================================================
    
    print("--- Cleanup ---\n");
    print("Deleting test entities...\n");
    
    // Delete category and index first
    yield active_users.delete_async();
    print("Deleted active_users category\n");
    
    yield search_index.delete_async();
    print("Deleted email_search index\n");
    
    // Delete all users
    foreach (var user in yield engine.query_by_type_async("User")) {
        string name = user.name;
        yield user.delete_async();
        print("Deleted %s\n", name);
    }
    
    // Delete the users container
    yield users.delete_async();
    print("Deleted users container\n");
    
    print("\nExample completed successfully!\n");
    print("\nTip: To test remote mode, start implexusd first:\n");
    print("  ./build/tools/implexusd/implexusd --port 9876 --storage ./server_data\n");
    print("  Then run: ./build/examples/basicusage --remote\n");
    
    return 0;
}