/**
 * @file  main.cpp
 * @brief A few short examples in a row.
 *
 *  Demonstrates how-to use the SQLite++ wrapper
 *
 * Copyright (c) 2012-2023 Sebastien Rombauts (sebastien.rombauts@gmail.com)
 *
 * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
 * or copy at http://opensource.org/licenses/MIT)
 */

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <string>

#include <SQLiteCpp/SQLiteCpp.h>
#include <SQLiteCpp/VariadicBind.h>


#ifdef SQLITECPP_ENABLE_ASSERT_HANDLER
namespace SQLite
{
/// definition of the assertion handler enabled when SQLITECPP_ENABLE_ASSERT_HANDLER is defined in the project (CMakeList.txt)
void assertion_failed(const char* apFile, const long apLine, const char* apFunc, const char* apExpr, const char* apMsg)
{
    // Print a message to the standard error output stream, and abort the program.
    std::cerr << apFile << ":" << apLine << ":" << " error: assertion failed (" << apExpr << ") in " << apFunc << "() with message \"" << apMsg << "\"\n";
    std::abort();
}
}
#endif

/// Get path to this example's directory (including the final separator '/' or '\')
static inline std::string getExamplePath()
{
    std::string filePath(__FILE__);
    return filePath.substr( 0, filePath.length() - std::string("main.cpp").length());
}

/// Example Database
static const std::string filename_example_db3   = getExamplePath() + "example.db3";
/// Image (SQLite logo as a 12581 bytes PNG file)
static const int sizeof_logo_png                = 12581;
static const std::string filename_logo_png      = getExamplePath() + "logo.png";


/// Object Oriented Basic example
class Example
{
public:
    // Constructor
    Example() :
        mDb(filename_example_db3),                                  // Open a database file in read-only mode
        mQuery(mDb, "SELECT * FROM test WHERE weight > :min_weight")// Compile a SQL query, containing one parameter (index 1)
    {
    }
    virtual ~Example()
    {
    }

    /// List the rows where the "weight" column is greater than the provided aParamValue
    void ListGreaterThan(const int aParamValue)
    {
        std::cout << "ListGreaterThan(" << aParamValue << ")\n";

        // Bind the integer value provided to the first parameter of the SQL query
        mQuery.bind(":min_weight", aParamValue); // same as mQuery.bind(1, aParamValue);

        // Loop to execute the query step by step, to get one a row of results at a time
        while (mQuery.executeStep())
        {
            std::cout << "row (" << mQuery.getColumn(0) << ", \"" << mQuery.getColumn(1) << "\", " << mQuery.getColumn(2) << ")\n";
        }

        // Reset the query to be able to use it again later
        mQuery.reset();
    }

private:
    SQLite::Database    mDb;    ///< Database connection
    SQLite::Statement   mQuery; ///< Database prepared SQL query
};

int main()
{
    // Using SQLITE_VERSION would require #include <sqlite3.h> which we want to avoid: use SQLite::VERSION if possible.
//  std::cout << "SQlite3 version " << SQLITE_VERSION << std::endl;
    std::cout << "SQlite3 version " << SQLite::VERSION << " (" << SQLite::getLibVersion() << ")" << std::endl;
    std::cout << "SQliteC++ version " << SQLITECPP_VERSION << std::endl;

    ////////////////////////////////////////////////////////////////////////////
    // Inspect a database via SQLite header information
    try
    {
       const SQLite::Header header = SQLite::Database::getHeaderInfo(filename_example_db3);

       // Print values for all header fields
       // Official documentation for fields can be found here: https://www.sqlite.org/fileformat.html#the_database_header
        std::cout << "Magic header string: " << header.headerStr << std::endl;
        std::cout << "Page size bytes: " << header.pageSizeBytes << std::endl;
        std::cout << "File format write version: " << (int)header.fileFormatWriteVersion << std::endl;
        std::cout << "File format read version: " << (int)header.fileFormatReadVersion << std::endl;
        std::cout << "Reserved space bytes: " << (int)header.reservedSpaceBytes << std::endl;
        std::cout << "Max embedded payload fraction " << (int)header.maxEmbeddedPayloadFrac << std::endl;
        std::cout << "Min embedded payload fraction: " << (int)header.minEmbeddedPayloadFrac << std::endl;
        std::cout << "Leaf payload fraction: " << (int)header.leafPayloadFrac << std::endl;
        std::cout << "File change counter: " << header.fileChangeCounter << std::endl;
        std::cout << "Database size pages: " << header.databaseSizePages << std::endl;
        std::cout << "First freelist trunk page: " << header.firstFreelistTrunkPage << std::endl;
        std::cout << "Total freelist trunk pages: " << header.totalFreelistPages << std::endl;
        std::cout << "Schema cookie: " << header.schemaCookie << std::endl;
        std::cout << "Schema format number: " << header.schemaFormatNumber << std::endl;
        std::cout << "Default page cache size bytes: " << header.defaultPageCacheSizeBytes << std::endl;
        std::cout << "Largest B tree page number: " << header.largestBTreePageNumber << std::endl;
        std::cout << "Database text encoding: " << header.databaseTextEncoding << std::endl;
        std::cout << "User version: " << header.userVersion << std::endl;
        std::cout << "Incremental vaccum mode: " << header.incrementalVaccumMode << std::endl;
        std::cout << "Application ID: " << header.applicationId << std::endl;
        std::cout << "Version valid for: " << header.versionValidFor << std::endl;
        std::cout << "SQLite version: " << header.sqliteVersion << std::endl;
    }
    catch (std::exception& e)
    {
        std::cout << "SQLite exception: " << e.what() << std::endl;
        return EXIT_FAILURE; // unexpected error : exit the example program
    }

    ////////////////////////////////////////////////////////////////////////////
    // Very basic first example (1/7) :
    try
    {
        // Open a database file in read-only mode
        SQLite::Database    db(filename_example_db3);  // SQLite::OPEN_READONLY
        std::cout << "SQLite database file '" << db.getFilename().c_str() << "' opened successfully\n";

        // Test if the 'test' table exists
        const bool bExists = db.tableExists("test");
        std::cout << "SQLite table 'test' exists=" << bExists << "\n";

        // Get a single value result with an easy to use shortcut
        const std::string value = db.execAndGet("SELECT value FROM test WHERE id=2");
        std::cout << "execAndGet=" << value.c_str() << std::endl;
    }
    catch (std::exception& e)
    {
        std::cout << "SQLite exception: " << e.what() << std::endl;
        return EXIT_FAILURE; // unexpected error : exit the example program
    }

    ////////////////////////////////////////////////////////////////////////////
    // Simple select query - few variations (2/7) :
    try
    {
        // Open a database file in read-only mode
        SQLite::Database    db(filename_example_db3);  // SQLite::OPEN_READONLY
        std::cout << "SQLite database file '" << db.getFilename().c_str() << "' opened successfully\n";

        ///// a) Loop to get values of column by index, using auto cast to variable type

        // Compile a SQL query, containing one parameter (index 1)
        SQLite::Statement   query(db, "SELECT id as test_id, value as test_val, weight as test_weight FROM test WHERE weight > ?");
        std::cout << "SQLite statement '" << query.getQuery().c_str() << "' compiled (" << query.getColumnCount() << " columns in the result)\n";
        // Bind the integer value 2 to the first parameter of the SQL query
        query.bind(1, 2);
        std::cout << "binded with integer value '2' :\n";

        // Loop to execute the query step by step, to get one a row of results at a time
        while (query.executeStep())
        {
            // Demonstrates how to get some typed column value (and the equivalent explicit call)
            const int         id     = query.getColumn(0); // = query.getColumn(0).getInt();
          //const char*       pvalue = query.getColumn(1); // = query.getColumn(1).getText();
            const std::string value  = query.getColumn(1); // = query.getColumn(1).getText();
            const int         bytes  = query.getColumn(1).size(); // .getColumn(1).getBytes();
            const double      weight = query.getColumn(2); // = query.getColumn(2).getInt();
            std::cout << "row (" << id << ", \"" << value.c_str() << "\"(" << bytes << ") " << weight << ")\n";
        }

        ///// b) Get aliased column names (and original column names if possible)

        // Reset the query to use it again
        query.reset();
        std::cout << "SQLite statement '" << query.getQuery().c_str() << "' reseted (" << query.getColumnCount() << " columns in the result)\n";

        // Show how to get the aliased names of the result columns.
        const std::string name0 = query.getColumnName(0);
        const std::string name1 = query.getColumnName(1);
        const std::string name2 = query.getColumnName(2);
        std::cout << "aliased result [\"" << name0.c_str() << "\", \"" << name1.c_str() << "\", \"" << name2.c_str() << "\"]\n";

#ifdef SQLITE_ENABLE_COLUMN_METADATA
        // Show how to get origin names of the table columns from which theses result columns come from.
        // Requires the SQLITE_ENABLE_COLUMN_METADATA preprocessor macro to be
        // also defined at compile times of the SQLite library itself.
        const std::string oname0 = query.getColumnOriginName(0);
        const std::string oname1 = query.getColumnOriginName(1);
        const std::string oname2 = query.getColumnOriginName(2);
        std::cout << "origin table 'test' [\"" << oname0.c_str() << "\", \"" << oname1.c_str() << "\", \"" << oname2.c_str() << "\"]\n";
#endif
        // Loop to execute the query step by step, to get one a row of results at a time
        while (query.executeStep())
        {
            // Demonstrates that inserting column value in a std:ostream is natural
            std::cout << "row (" << query.getColumn(0) << ", \"" << query.getColumn(1) << "\", " << query.getColumn(2) << ")\n";
        }

        ///// c) Get columns by name

        // Reset the query to use it again
        query.reset();
        std::cout << "SQLite statement '" << query.getQuery().c_str() << "' reseted (" << query.getColumnCount() << " columns in the result)\n";

        // Loop to execute the query step by step, to get one a row of results at a time
        while (query.executeStep())
        {
            // Demonstrates how to get column value by aliased name (not the original table names, see above)
            const int         id     = query.getColumn("test_id");
            const std::string value  = query.getColumn("test_val");
            const double      weight = query.getColumn("test_weight");
            std::cout << "row (" << id << ", \"" << value.c_str() << "\" " << weight << ")\n";
        }

        ///// d) Uses explicit typed getters instead of auto cast operators

        // Reset the query to use it again
        query.reset();
        std::cout << "SQLite statement '" << query.getQuery().c_str() << "' reseted (" << query.getColumnCount () << " columns in the result)\n";
        // Bind the string value "6" to the first parameter of the SQL query
        query.bind(1, "6");
        std::cout << "binded with string value \"6\" :\n";
        // Reuses variables: uses assignment operator in the loop instead of constructor with initialization
        int         id = 0;
        std::string value;
        double      weight = 0.0;
        while (query.executeStep())
        {
            id        = query.getColumn(0).getInt();
            value     = query.getColumn(1).getText();
            weight    = query.getColumn(2).getInt();
            std::cout << "row (" << id << ", \"" << value << "\", " << weight << ")\n";
        }
    }
    catch (std::exception& e)
    {
        std::cout << "SQLite exception: " << e.what() << std::endl;
        return EXIT_FAILURE; // unexpected error : exit the example program
    }

    ////////////////////////////////////////////////////////////////////////////
    // Object Oriented Basic example (3/7) :
    try
    {
        // Open the database and compile the query
        Example example;

        // Demonstrates the way to use the same query with different parameter values
        example.ListGreaterThan(8);
        example.ListGreaterThan(6);
        example.ListGreaterThan(2);
    }
    catch (std::exception& e)
    {
        std::cout << "SQLite exception: " << e.what() << std::endl;
        return EXIT_FAILURE; // unexpected error : exit the example program
    }

    // The execAndGet wrapper example (4/7) :
    try
    {
        // Open a database file in read-only mode
        SQLite::Database    db(filename_example_db3);  // SQLite::OPEN_READONLY
        std::cout << "SQLite database file '" << db.getFilename().c_str() << "' opened successfully\n";

        // WARNING: Be very careful with this dangerous method: you have to
        // make a COPY OF THE result, else it will be destroy before the next line
        // (when the underlying temporary Statement and Column objects are destroyed)
        std::string value = db.execAndGet("SELECT value FROM test WHERE id=2");
        std::cout << "execAndGet=" << value.c_str() << std::endl;
    }
    catch (std::exception& e)
    {
        std::cout << "SQLite exception: " << e.what() << std::endl;
        return EXIT_FAILURE; // unexpected error : exit the example program
    }

    ////////////////////////////////////////////////////////////////////////////
    // Simple batch queries example (5/7) :
    try
    {
        // Open a database file in create/write mode
        SQLite::Database    db("test.db3", SQLite::OPEN_READWRITE|SQLite::OPEN_CREATE);
        std::cout << "SQLite database file '" << db.getFilename().c_str() << "' opened successfully\n";

        // Create a new table with an explicit "id" column aliasing the underlying rowid
        db.exec("DROP TABLE IF EXISTS test");
        db.exec("CREATE TABLE test (id INTEGER PRIMARY KEY, value TEXT)");

        // first row
        int nb = db.exec("INSERT INTO test VALUES (NULL, \"test\")");
        std::cout << "INSERT INTO test VALUES (NULL, \"test\")\", returned " << nb << std::endl;

        // second row
        nb = db.exec("INSERT INTO test VALUES (NULL, \"second\")");
        std::cout << "INSERT INTO test VALUES (NULL, \"second\")\", returned " << nb << std::endl;

        // update the second row
        nb = db.exec("UPDATE test SET value=\"second-updated\" WHERE id='2'");
        std::cout << "UPDATE test SET value=\"second-updated\" WHERE id='2', returned " << nb << std::endl;

        nb = db.getTotalChanges();
        std::cout << "Nb of total changes since connection: " << nb << std::endl;

        // Check the results : expect two row of result
        SQLite::Statement   query(db, "SELECT * FROM test");
        std::cout << "SELECT * FROM test :\n";
        while (query.executeStep())
        {
            std::cout << "row (" << query.getColumn(0) << ", \"" << query.getColumn(1) << "\")\n";
        }

        db.exec("DROP TABLE test");
    }
    catch (std::exception& e)
    {
        std::cout << "SQLite exception: " << e.what() << std::endl;
        return EXIT_FAILURE; // unexpected error : exit the example program
    }
    remove("test.db3");

    ////////////////////////////////////////////////////////////////////////////
    // RAII transaction example (6/7) :
    try
    {
        // Open a database file in create/write mode
        SQLite::Database    db("transaction.db3", SQLite::OPEN_READWRITE|SQLite::OPEN_CREATE);
        std::cout << "SQLite database file '" << db.getFilename().c_str() << "' opened successfully\n";

        db.exec("DROP TABLE IF EXISTS test");

        // Exemple of a successful transaction :
        try
        {
            // Begin transaction
            SQLite::Transaction transaction(db);

            db.exec("CREATE TABLE test (id INTEGER PRIMARY KEY, value TEXT)");

            int nb = db.exec("INSERT INTO test VALUES (NULL, \"test\")");
            std::cout << "INSERT INTO test VALUES (NULL, \"test\")\", returned " << nb << std::endl;

            // Commit transaction
            transaction.commit();
        }
        catch (std::exception& e)
        {
            std::cout << "SQLite exception: " << e.what() << std::endl;
            return EXIT_FAILURE; // unexpected error : exit the example program
        }

        // Exemple of a rollbacked transaction :
        try
        {
            // Begin transaction
            SQLite::Transaction transaction(db);

            int nb = db.exec("INSERT INTO test VALUES (NULL, \"second\")");
            std::cout << "INSERT INTO test VALUES (NULL, \"second\")\", returned " << nb << std::endl;

            nb = db.exec("INSERT INTO test ObviousError");
            std::cout << "INSERT INTO test \"error\", returned " << nb << std::endl;

            return EXIT_FAILURE; // we should never get there : exit the example program

            // Commit transaction
            transaction.commit();
        }
        catch (std::exception& e)
        {
            std::cout << "SQLite exception: " << e.what() << std::endl;
            // expected error, see above
        }

        // Check the results (expect only one row of result, as the second one has been rollbacked by the error)
        SQLite::Statement   query(db, "SELECT * FROM test");
        std::cout << "SELECT * FROM test :\n";
        while (query.executeStep())
        {
            std::cout << "row (" << query.getColumn(0) << ", \"" << query.getColumn(1) << "\")\n";
        }
    }
    catch (std::exception& e)
    {
        std::cout << "SQLite exception: " << e.what() << std::endl;
        return EXIT_FAILURE; // unexpected error : exit the example program
    }
    remove("transaction.db3");

    ////////////////////////////////////////////////////////////////////////////
    // Binary blob and in-memory database example (7/7) :
    try
    {
        // Open a database file in create/write mode
        SQLite::Database    db(":memory:", SQLite::OPEN_READWRITE|SQLite::OPEN_CREATE);
        std::cout << "SQLite database file '" << db.getFilename().c_str() << "' opened successfully\n";

        db.exec("DROP TABLE IF EXISTS test");
        db.exec("CREATE TABLE test (id INTEGER PRIMARY KEY, value BLOB)");

        // A) insert the logo.png image into the db as a blob
        FILE* fp = fopen(filename_logo_png.c_str(), "rb");
        if (NULL != fp)
        {
            char  buffer[16*1024];
            static_assert(sizeof(buffer) > sizeof_logo_png, "Buffer is smaller than the size of the file to read");
            void* blob = &buffer;
            const int size = static_cast<int>(fread(blob, 1, 16*1024, fp));
            buffer[size] = '\0';
            SQLITECPP_ASSERT(size == sizeof_logo_png, "unexpected fread return value");   // See SQLITECPP_ENABLE_ASSERT_HANDLER
            fclose(fp);
            std::cout << filename_logo_png << " file size=" << size << " bytes\n";

            // Insert query
            SQLite::Statement   query(db, "INSERT INTO test VALUES (NULL, ?)");
            // Bind the blob value to the first parameter of the SQL query
            query.bind(1, blob, size);
            std::cout << "blob binded successfully\n";

            // Execute the one-step query to insert the blob
            int nb = query.exec();
            std::cout << "INSERT INTO test VALUES (NULL, ?)\", returned " << nb << std::endl;
        }
        else
        {
            std::cout << "file " << filename_logo_png << " not found !\n";
            return EXIT_FAILURE; // unexpected error : exit the example program
        }

        // B) select the blob from the db and write it to disk into a "out.png" image file
        fp = fopen("out.png", "wb");
        if (NULL != fp)
        {
            SQLite::Statement   query(db, "SELECT * FROM test");
            std::cout << "SELECT * FROM test :\n";
            if (query.executeStep())
            {
                SQLite::Column colBlob = query.getColumn(1);
                const void* const blob = colBlob.getBlob();
                const size_t size = colBlob.getBytes();
                std::cout << "row (" << query.getColumn(0) << ", size=" << size << " bytes)\n";
                size_t sizew = fwrite(blob, 1, size, fp);
                SQLITECPP_ASSERT(sizew == size, "fwrite failed");   // See SQLITECPP_ENABLE_ASSERT_HANDLER
                fclose(fp);
            }
            // NOTE: here the blob is still held in memory, until the Statement is finalized at the end of the scope
        }
        else
        {
            std::cout << "file out.png not created !\n";
            return EXIT_FAILURE; // unexpected error : exit the example program
        }
    }
    catch (std::exception& e)
    {
        std::cout << "SQLite exception: " << e.what() << std::endl;
        return EXIT_FAILURE; // unexpected error : exit the example program
    }
    remove("out.png");

#if (__cplusplus >= 201402L) || ( defined(_MSC_VER) && (_MSC_VER >= 1900) ) // c++14: Visual Studio 2015
    // example with C++14 variadic bind
    try
    {
        // Open a database file in create/write mode
        SQLite::Database db(":memory:", SQLite::OPEN_READWRITE|SQLite::OPEN_CREATE);

        db.exec("DROP TABLE IF EXISTS test");
        db.exec("CREATE TABLE test (id INTEGER PRIMARY KEY, value TEXT)");

        {
            SQLite::Statement query(db, "INSERT INTO test VALUES (?, ?)");

            SQLite::bind(query, 42, "fortytwo");
            // Execute the one-step query to insert the blob
            int nb = query.exec();
            std::cout << "INSERT INTO test VALUES (NULL, ?)\", returned " << nb << std::endl;
        }

        SQLite::Statement query(db, "SELECT * FROM test");
        std::cout << "SELECT * FROM test :\n";
        if (query.executeStep())
        {
            std::cout << query.getColumn(0).getInt() << "\t\"" << query.getColumn(1).getText() << "\"\n";
        }
    }
    catch (std::exception& e)
    {
        std::cout << "SQLite exception: " << e.what() << std::endl;
        return EXIT_FAILURE; // unexpected error : exit the example program
    }
#endif

    std::cout << "everything ok, quitting\n";

    return EXIT_SUCCESS;
}