forge-sql-orm-cli/src/actions/migrations-update.ts

CLI tool for Forge SQL ORM

import "reflect-metadata";
import fs from "fs";
import path from "path";
import mysql from "mysql2/promise";
import { MySqlTable, TableConfig } from "drizzle-orm/mysql-core";
import { RowDataPacket } from "mysql2";
import { getTableMetadata } from "forge-sql-orm";
import { AnyIndexBuilder } from "drizzle-orm/mysql-core/indexes";
import { ForeignKeyBuilder } from "drizzle-orm/mysql-core/foreign-keys";
import { UniqueConstraintBuilder } from "drizzle-orm/mysql-core/unique-constraint";
import { v4 as uuid } from "uuid";

interface DrizzleColumn {
  type: string;
  notNull: boolean;
  autoincrement?: boolean;
  columnType?: any;
  name: string;
  default?: string;
  getSQLType: () => string;
}

interface DrizzleSchema {
  [tableName: string]: {
    [columnName: string]: DrizzleColumn;
  };
}

interface DatabaseColumn extends RowDataPacket {
  TABLE_NAME: string;
  COLUMN_NAME: string;
  COLUMN_TYPE: string;
  IS_NULLABLE: string;
  COLUMN_KEY: string;
  EXTRA: string;
}

interface DatabaseIndex extends RowDataPacket {
  TABLE_NAME: string;
  INDEX_NAME: string;
  COLUMN_NAME: string;
  NON_UNIQUE: number;
}

interface DatabaseForeignKey extends RowDataPacket {
  TABLE_NAME: string;
  COLUMN_NAME: string;
  CONSTRAINT_NAME: string;
  REFERENCED_TABLE_NAME: string;
  REFERENCED_COLUMN_NAME: string;
}

interface TableSchema {
  columns: Record<string, DatabaseColumn>;
  indexes: Record<
    string,
    {
      columns: string[];
      unique: boolean;
    }
  >;
  foreignKeys: Record<
    string,
    {
      column: string;
      referencedTable: string;
      referencedColumn: string;
    }
  >;
}

interface DatabaseSchema {
  [tableName: string]: TableSchema;
}

type PreMigrationNotNull = {
  tableName: string;
  dbTable: TableSchema;
  colName: string;
  type: string;
  migrationType: "NEW_FIELD_NOT_NULL" | "MODIFY_NOT_NULL" | "INLINE";
  defaultValue: string;
};

function buildDefault(preMigration: PreMigrationNotNull): string {
  const def = preMigration.defaultValue;
  const type = preMigration.type.toLowerCase();

  // No default defined
  if (def === undefined || def === null) {
    return "";
  }

  // Empty string default → DEFAULT ''
  if (def === "") {
    return `''`;
  }

  // Types that must be quoted
  const stringTypes = new Set([
    "char",
    "varchar",
    "text",
    "tinytext",
    "mediumtext",
    "longtext",
    "enum",
    "set",
    "binary",
    "varbinary",
    "blob",
  ]);

  // Numeric types that accept numeric literals
  const numericTypes = new Set([
    "tinyint",
    "smallint",
    "mediumint",
    "int",
    "bigint",
    "decimal",
    "float",
    "double",
    "bit",
  ]);

  // Check if default value is a numeric literal
  const isNumericLiteral = /^[+-]?\d+(\.\d+)?$/.test(def);

  // Numeric types → DEFAULT 123 (no quotes)
  if (numericTypes.has(type) && isNumericLiteral) {
    return `${def}`;
  }

  // String types → DEFAULT 'value'
  if (stringTypes.has(type)) {
    // Double escape single quotes
    const escaped = def.replace(/'/g, "''");
    return `'${escaped}'`;
  }

  // Other types: treat default as an expression
  // e.g. DEFAULT CURRENT_TIMESTAMP, DEFAULT (uuid()), DEFAULT now()
  return `${def}`;
}

/**
 * Generates warning message for missing default value
 */
function generateWarningMessage(tableName: string, colName: string, version: number): string {
  return (
    `⚠️  WARNING: Field \`${tableName}\`.\`${colName}\` requires a default value for existing NULL records.\n` +
    `   Action required in migration file: migrationV${version}.ts\n` +
    `   Find the line with: UPDATE \`${tableName}\` SET \`${colName}\` = ?\n` +
    `   Replace '?' with an actual value (e.g., '' for strings, 0 for numbers, '1970-01-01' for dates)\n` +
    `   OR remove this migration if it's not needed.`
  );
}

/**
 * Handles warning for missing default value
 */
function handleMissingDefaultValue(
  preMigration: PreMigrationNotNull,
  version: number,
  migrationLineList: string[],
): void {
  const warningMsg = generateWarningMessage(preMigration.tableName, preMigration.colName, version);
  console.warn(warningMsg);
  migrationLineList.push(`console.error(${JSON.stringify(warningMsg)});`);
}

/**
 * Gets the default value for UPDATE statement
 */
function getUpdateDefaultValue(preMigration: PreMigrationNotNull, defaultValue: string): string {
  return defaultValue === "?" ? defaultValue : buildDefault(preMigration);
}

/**
 * Generates UPDATE statement for existing NULL records
 */
function generateUpdateStatement(preMigration: PreMigrationNotNull, defaultValue: string): string {
  const updateValue = getUpdateDefaultValue(preMigration, defaultValue);
  return `UPDATE \`${preMigration.tableName}\` SET \`${preMigration.colName}\` = ${updateValue} WHERE \`${preMigration.colName}\` IS NULL`;
}

/**
 * Generates a migration file using the provided SQL statements.
 * @param createStatements - Array of SQL statements.
 * @param version - Migration version number.
 * @returns TypeScript migration file content.
 */
function generateMigrationFile(
  createStatements: {
    changes: { change: string; premigrationId?: string }[];
    preMigrations: Record<string, PreMigrationNotNull>;
  },
  version: number,
): string {
  const versionPrefix = `v${version}_MIGRATION`;
  const migrationLineList: string[] = [];

  createStatements.changes.forEach((change, index) => {
    if (!change.premigrationId) {
      // Regular change without pre-migration
      migrationLineList.push(
        `\nmigrationRunner.enqueue("${versionPrefix}${index}", "${change.change}")`,
      );
      return;
    }

    const preMigration = createStatements.preMigrations[change.premigrationId];
    if (!preMigration) {
      // Pre-migration ID exists but pre-migration not found
      migrationLineList.push(
        `\nmigrationRunner.enqueue("${versionPrefix}${index}", "${change.change}")`,
      );
      return;
    }

    const defaultValue =
      preMigration.defaultValue === undefined || preMigration.defaultValue === null
        ? "?"
        : preMigration.defaultValue;
    const needsWarning = defaultValue === "?";

    if (preMigration.migrationType === "NEW_FIELD_NOT_NULL") {
      // Step 1: Add column as NULL
      const addColumnStatement = change.change.replace("NOT NULL", "NULL");
      migrationLineList.push(
        `\nmigrationRunner.enqueue("${versionPrefix}${index}_NULLABLE", "${addColumnStatement}");`,
      );

      // Step 2: Warning if default value is missing
      if (needsWarning) {
        handleMissingDefaultValue(preMigration, version, migrationLineList);
      }

      // Step 3: Update existing NULL records
      const updateStatement = generateUpdateStatement(preMigration, defaultValue);
      migrationLineList.push(
        `\nmigrationRunner.enqueue("${versionPrefix}${index}_UPDATE_EXISTS_RECORDS", "${updateStatement}");`,
      );

      // Step 4: Modify column to NOT NULL
      const defaultClause = defaultValue === "?" ? "" : ` DEFAULT ${buildDefault(preMigration)}`;
      const modifyStatement = `ALTER TABLE \`${preMigration.tableName}\` MODIFY COLUMN IF EXISTS \`${preMigration.colName}\` ${preMigration.type} NOT NULL${defaultClause};`;
      migrationLineList.push(
        `\nmigrationRunner.enqueue("${versionPrefix}${index}", "${modifyStatement}");`,
      );
    } else if (preMigration.migrationType === "MODIFY_NOT_NULL") {
      // Step 1: Warning if default value is missing
      if (needsWarning) {
        handleMissingDefaultValue(preMigration, version, migrationLineList);
      }

      // Step 2: Update existing NULL records
      const updateStatement = generateUpdateStatement(preMigration, defaultValue);
      migrationLineList.push(
        `\nmigrationRunner.enqueue("${versionPrefix}${index}_UPDATE_EXISTS_RECORDS", "${updateStatement}")`,
      );

      // Step 3: Apply the MODIFY statement
      migrationLineList.push(
        `\nmigrationRunner.enqueue("${versionPrefix}${index}", "${change.change}")`,
      );
    }
  });

  const migrationLines = migrationLineList.join("\n");

  return `import { MigrationRunner } from "@forge/sql/out/migration";

export default (migrationRunner: MigrationRunner): MigrationRunner => { 
${migrationLines};
return migrationRunner;
};`;
}

/**
 * Filters out SQL statements that already exist in the previous migration file
 * @param newStatements - Array of SQL statements from new migration
 * @param prevVersion - Previous migration version
 * @param outputDir - Directory where migration files are stored
 * @returns Array of SQL statements that don't exist in previous migration
 */
function filterWithPreviousMigration(
  newStatements: {
    changes: { change: string; premigrationId?: string }[];
    preMigrations: Record<string, PreMigrationNotNull>;
  },
  prevVersion: number,
  outputDir: string,
): {
  changes: { change: string; premigrationId?: string }[];
  preMigrations: Record<string, PreMigrationNotNull>;
} {
  const prevMigrationPath = path.join(outputDir, `migrationV${prevVersion}.ts`);

  if (!fs.existsSync(prevMigrationPath)) {
    return {
      changes: newStatements.changes.map((s) => ({
        change: s.change.replace(/\s+/g, " "),
        premigrationId: s.premigrationId,
      })),
      preMigrations: newStatements.preMigrations,
    };
  }

  // Read previous migration file
  const prevContent = fs.readFileSync(prevMigrationPath, "utf-8");

  // Extract SQL statements from the file
  const prevStatements = prevContent
    .split("\n")
    .filter((line) => line.includes(".enqueue("))
    .map((line) => {
      const match = line.match(/\.enqueue\([^,]+,\s*"([^"]+)"/);
      return match ? match[1].replace(/\s+/g, " ").trim() : "";
    });

  // Filter out statements that already exist in previous migration
  return {
    preMigrations: newStatements.preMigrations,
    changes: newStatements.changes
      .filter((s) => !prevStatements.includes(s.change.replace(/\s+/g, " ")))
      .map((s) => ({ change: s.change.replace(/\s+/g, " "), premigrationId: s.premigrationId })),
  };
}

/**
 * Saves the generated migration file along with `migrationCount.ts` and `index.ts`.
 * @param migrationCode - The migration code to be written to the file.
 * @param version - Migration version number.
 * @param outputDir - Directory where the migration files will be saved.
 * @returns boolean indicating if migration was saved
 */
function saveMigrationFiles(migrationCode: string, version: number, outputDir: string): boolean {
  if (!fs.existsSync(outputDir)) {
    fs.mkdirSync(outputDir, { recursive: true });
  }

  const migrationFilePath = path.join(outputDir, `migrationV${version}.ts`);
  const migrationCountPath = path.join(outputDir, `migrationCount.ts`);
  const indexFilePath = path.join(outputDir, `index.ts`);

  // Write the migration file
  fs.writeFileSync(migrationFilePath, migrationCode);

  // Write the migration count file
  fs.writeFileSync(migrationCountPath, `export const MIGRATION_VERSION = ${version};`);

  // Generate the migration index file with static imports
  const importLines: string[] = [];
  const callLines: string[] = [];

  for (let i = 1; i <= version; i++) {
    importLines.push(`import migrationV${i} from "./migrationV${i}";`);
    callLines.push(`  migrationV${i}(migrationRunner);`);
  }

  const indexFileContent = `import { MigrationRunner } from "@forge/sql/out/migration";
${importLines.join("\n")}

export type MigrationType = (
  migrationRunner: MigrationRunner,
) => MigrationRunner;

export default (
  migrationRunner: MigrationRunner,
): MigrationRunner => {
${callLines.join("\n")}
  return migrationRunner;
};`;

  fs.writeFileSync(indexFilePath, indexFileContent);

  console.log(`✅ Migration file created: ${migrationFilePath}`);
  console.log(`✅ Migration count file updated: ${migrationCountPath}`);
  console.log(`✅ Migration index file created: ${indexFilePath}`);

  return true;
}

/**
 * Loads the current migration version from `migrationCount.ts`.
 * @param migrationPath - Path to the migration folder.
 * @returns The latest migration version.
 */
const loadMigrationVersion = async (migrationPath: string): Promise<number> => {
  try {
    const migrationCountFilePath = path.resolve(path.join(migrationPath, "migrationCount.ts"));
    if (!fs.existsSync(migrationCountFilePath)) {
      console.warn(
        `⚠️ Warning: migrationCount.ts not found in ${migrationCountFilePath}, assuming no previous migrations.`,
      );
      return 0;
    }

    const { MIGRATION_VERSION } = await import(migrationCountFilePath);
    console.log(`✅ Current migration version: ${MIGRATION_VERSION}`);
    return MIGRATION_VERSION as number;
  } catch (error) {
    console.error(`❌ Error loading migrationCount:`, error);
    process.exit(1);
  }
};

/**
 * Gets the current database schema from MySQL including indexes and foreign keys
 * @param connection - MySQL connection
 * @param dbName - Database name
 * @returns Database schema object with indexes and foreign keys
 */
async function getDatabaseSchema(
  connection: mysql.Connection,
  dbName: string,
): Promise<DatabaseSchema> {
  // Get columns
  const [columns] = await connection.execute<DatabaseColumn[]>(
    `
    SELECT TABLE_NAME, COLUMN_NAME, COLUMN_TYPE, IS_NULLABLE, COLUMN_KEY, EXTRA, COLUMN_DEFAULT
    FROM INFORMATION_SCHEMA.COLUMNS
    WHERE TABLE_SCHEMA = ?
  `,
    [dbName],
  );

  // Get indexes
  const [indexes] = await connection.execute<DatabaseIndex[]>(
    `
    SELECT TABLE_NAME, INDEX_NAME, COLUMN_NAME, NON_UNIQUE
    FROM INFORMATION_SCHEMA.STATISTICS
    WHERE TABLE_SCHEMA = ?
    ORDER BY TABLE_NAME, INDEX_NAME, SEQ_IN_INDEX
  `,
    [dbName],
  );

  // Get foreign keys
  const [foreignKeys] = await connection.execute<DatabaseForeignKey[]>(
    `
    SELECT 
      TABLE_NAME,
      COLUMN_NAME,
      CONSTRAINT_NAME,
      REFERENCED_TABLE_NAME,
      REFERENCED_COLUMN_NAME
    FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
    WHERE TABLE_SCHEMA = ?
    AND REFERENCED_TABLE_NAME IS NOT NULL
  `,
    [dbName],
  );

  const schema: DatabaseSchema = {};

  // Process columns
  columns.forEach((row) => {
    if (!schema[row.TABLE_NAME]) {
      schema[row.TABLE_NAME] = {
        columns: {},
        indexes: {},
        foreignKeys: {},
      };
    }
    schema[row.TABLE_NAME].columns[row.COLUMN_NAME] = row;
  });

  // Process indexes
  indexes.forEach((row) => {
    if (!schema[row.TABLE_NAME].indexes[row.INDEX_NAME]) {
      schema[row.TABLE_NAME].indexes[row.INDEX_NAME] = {
        columns: [],
        unique: !row.NON_UNIQUE,
      };
    }
    schema[row.TABLE_NAME].indexes[row.INDEX_NAME].columns.push(row.COLUMN_NAME);
  });

  // Process foreign keys
  foreignKeys.forEach((row) => {
    if (!schema[row.TABLE_NAME].foreignKeys[row.CONSTRAINT_NAME]) {
      schema[row.TABLE_NAME].foreignKeys[row.CONSTRAINT_NAME] = {
        column: row.COLUMN_NAME,
        referencedTable: row.REFERENCED_TABLE_NAME,
        referencedColumn: row.REFERENCED_COLUMN_NAME,
      };
    }
  });

  return schema;
}

/**
 * Converts MySQL type to normalized format for comparison
 * @param mysqlType - MySQL type from INFORMATION_SCHEMA or Drizzle type
 * @returns Normalized type string
 */
function normalizeMySQLType(mysqlType: string): string {
  // Remove length/precision information
  let normalized = mysqlType.replace(/\([^)]*\)/, "").toLowerCase();

  // Remove 'mysql' prefix from Drizzle types
  normalized = normalized.replace(/^mysql/, "");

  return normalized;
}

/**
 * Gets the name of a foreign key constraint
 * @param fk - The foreign key builder
 * @returns The name of the foreign key constraint
 */
function getForeignKeyName(fk: ForeignKeyBuilder): string {
  // @ts-ignore - Internal property access
  return fk.name;
}

/**
 * Gets the name of an index
 * @param index - The index builder
 * @returns The name of the index
 */
function getIndexName(index: AnyIndexBuilder): string {
  // @ts-ignore - Internal property access
  return index.name;
}

/**
 * Gets the name of a unique constraint
 * @param uc - The unique constraint builder
 * @returns The name of the unique constraint
 */
function getUniqueConstraintName(uc: UniqueConstraintBuilder): string {
  // @ts-ignore - Internal property access
  return uc.name;
}

/**
 * Gets the columns of an index
 * @param index - The index builder
 * @returns Array of column names
 */
function getIndexColumns(index: AnyIndexBuilder): string[] {
  // @ts-ignore - Internal property access
  return index.columns.map((col) => col.name);
}

function compareForeignKey(
  fk: ForeignKeyBuilder,
  { columns }: { columns: string[]; unique: boolean },
) {
  // @ts-ignore
  const fcolumns: string[] = fk.columns.map((c) => c.name);
  return fcolumns.sort().join(",") === columns.sort().join(",");
}

/**
 * Generates SQL changes by comparing Drizzle schema with database schema
 * @param drizzleSchema - Schema from Drizzle
 * @param dbSchema - Schema from database
 * @param schemaModule - Drizzle schema module
 * @returns Array of SQL statements
 */
function generateSchemaChanges(
  drizzleSchema: DrizzleSchema,
  dbSchema: DatabaseSchema,
  schemaModule: Record<string, any>,
): {
  changes: { change: string; premigrationId?: string }[];
  preMigrations: Record<string, PreMigrationNotNull>;
} {
  const changes: { change: string; premigrationId?: string }[] = [];
  const preMigrations: Record<string, PreMigrationNotNull> = {};
  // First check existing tables in database
  for (const [tableName, dbTable] of Object.entries(dbSchema)) {
    const drizzleColumns = drizzleSchema[tableName];

    if (!drizzleColumns) {
      // Table exists in database but not in schema - create it
      const columns = Object.entries(dbTable.columns)
        .map(([colName, col]) => {
          const type = col.COLUMN_TYPE;
          const nullable = col.IS_NULLABLE === "YES" ? "NULL" : "NOT NULL";
          const autoIncrement = col.EXTRA.includes("auto_increment") ? "AUTO_INCREMENT" : "";
          return `\`${colName}\` ${type} ${nullable} ${autoIncrement}`.trim();
        })
        .join(",\n  ");

      changes.push({ change: `CREATE TABLE if not exists \`${tableName}\` (\n  ${columns}\n);` });

      // Create indexes for new table
      for (const [indexName, dbIndex] of Object.entries(dbTable.indexes)) {
        // Skip primary key and foreign key indexes
        if (indexName === "PRIMARY") {
          continue;
        }

        // Check if any column in this index is a foreign key
        const isForeignKeyIndex = dbIndex.columns.some((colName) => {
          const column = dbTable.columns[colName];
          return column && column.COLUMN_KEY === "MUL" && column.EXTRA.includes("foreign key");
        });

        if (isForeignKeyIndex) {
          continue;
        }

        // Create index
        const columns = dbIndex.columns.map((col) => `\`${col}\``).join(", ");
        const unique = dbIndex.unique ? "UNIQUE " : "";
        changes.push({
          change: `CREATE  ${unique}INDEX if not exists  \`${indexName}\` ON \`${tableName}\` (${columns});`,
        });
      }

      // Create foreign keys for new table
      for (const [fkName, dbFK] of Object.entries(dbTable.foreignKeys)) {
        changes.push({
          change: `ALTER TABLE \`${tableName}\` ADD CONSTRAINT \`${fkName}\` FOREIGN KEY (\`${dbFK.column}\`) REFERENCES \`${dbFK.referencedTable}\` (\`${dbFK.referencedColumn}\`);`,
        });
      }
      continue;
    }

    // Check for column changes in existing tables
    for (const [colName, dbCol] of Object.entries(dbTable.columns)) {
      const drizzleCol = Object.values(drizzleColumns).find((c) => c.name === colName);

      if (!drizzleCol) {
        // Column exists in database but not in schema - create it
        const type = dbCol.COLUMN_TYPE;
        const nullable = dbCol.IS_NULLABLE === "YES" ? "NULL" : "NOT NULL";
        let premigrationId = nullable === "NOT NULL" ? uuid() : undefined;
        const defaultValue = dbCol.COLUMN_DEFAULT;
        if (nullable === "NOT NULL") {
          premigrationId = uuid();
          preMigrations[premigrationId] = {
            tableName,
            dbTable,
            colName,
            type,
            migrationType: "NEW_FIELD_NOT_NULL",
            defaultValue,
          };
        }
        changes.push({
          change: `ALTER TABLE \`${tableName}\` ADD COLUMN IF NOT EXISTS \`${colName}\` ${type} ${nullable} ${
            defaultValue === undefined || defaultValue === null
              ? ""
              : `DEFAULT ${buildDefault({
                  tableName,
                  dbTable,
                  colName,
                  type,
                  migrationType: "INLINE",
                  defaultValue: defaultValue,
                })}`
          };`,
          premigrationId,
        });
        continue;
      }

      // Check for column changes (type, nullability, or default value)
      const normalizedDbType = normalizeMySQLType(dbCol.COLUMN_TYPE);
      const normalizedDrizzleType = normalizeMySQLType(drizzleCol.getSQLType());
      const nullable = dbCol.IS_NULLABLE === "YES" ? "NULL" : "NOT NULL";
      const dbIsNotNull = nullable === "NOT NULL";
      const drizzleIsNotNull = drizzleCol.notNull;

      // Check if type has changed
      const typeChanged = normalizedDbType !== normalizedDrizzleType;

      // Check if nullability has changed
      const nullabilityChanged = dbIsNotNull !== drizzleIsNotNull;

      // Check if default value has changed
      const hasDrizzleDefault = drizzleCol.default !== null && drizzleCol.default !== undefined;
      const hasDbDefault = dbCol.COLUMN_DEFAULT !== null && dbCol.COLUMN_DEFAULT !== undefined;
      const defaultChanged =
        hasDrizzleDefault && hasDbDefault && !drizzleCol.default?.includes(dbCol.COLUMN_DEFAULT);

      // Column needs modification if any of these changed
      if (typeChanged || nullabilityChanged || defaultChanged) {
        const type = dbCol.COLUMN_TYPE; // Use database type as source of truth
        const defaultValue = dbCol.COLUMN_DEFAULT;

        // Determine if we need a pre-migration for NOT NULL constraint
        let premigrationId: string | undefined = undefined;
        if (dbIsNotNull && !drizzleIsNotNull) {
          // Changing from NULL to NOT NULL - need pre-migration
          premigrationId = uuid();
          preMigrations[premigrationId] = {
            tableName,
            dbTable,
            colName,
            type,
            migrationType: "MODIFY_NOT_NULL",
            defaultValue: defaultValue,
          };
        }

        // Build DEFAULT clause if default value exists
        let defaultClause = "";
        if (defaultValue !== undefined && defaultValue !== null) {
          const defaultValueObj: PreMigrationNotNull = {
            tableName,
            dbTable,
            colName,
            type,
            migrationType: "INLINE",
            defaultValue: defaultValue,
          };
          defaultClause = ` DEFAULT ${buildDefault(defaultValueObj)}`;
        }

        // Generate MODIFY COLUMN statement
        const modifyStatement = `ALTER TABLE \`${tableName}\` MODIFY COLUMN IF EXISTS \`${colName}\` ${type} ${nullable}${defaultClause};`;

        changes.push({
          change: modifyStatement,
          premigrationId,
        });
      }
    }

    // Check for index changes
    const table = Object.values(schemaModule).find((t) => {
      const metadata = getTableMetadata(t);
      return metadata.tableName === tableName;
    });

    if (table) {
      const metadata = getTableMetadata(table);
      // First check indexes that exist in database but not in schema
      for (const [indexName, dbIndex] of Object.entries(dbTable.indexes)) {
        // Skip primary key and foreign key indexes
        if (indexName === "PRIMARY") {
          continue;
        }

        // Check if this is a foreign key index
        const isForeignKeyIndex = metadata.foreignKeys.some(
          (fk) => getForeignKeyName(fk) === indexName || compareForeignKey(fk, dbIndex),
        );
        if (isForeignKeyIndex) {
          continue;
        }

        // Check if this is a unique constraint
        const existsUniqIndex = metadata.uniqueConstraints.find(
          (uc) => getUniqueConstraintName(uc) === indexName,
        );
        let drizzleIndex = metadata.indexes.find((i) => getIndexName(i) === indexName);

        if (!drizzleIndex && existsUniqIndex) {
          drizzleIndex = existsUniqIndex as unknown as AnyIndexBuilder;
        }

        if (!drizzleIndex) {
          // Index exists in database but not in schema - create it
          const columns = dbIndex.columns.map((col) => `\`${col}\``).join(", ");
          const unique = dbIndex.unique ? "UNIQUE " : "";
          changes.push({
            change: `CREATE ${unique}INDEX if not exists \`${indexName}\` ON \`${tableName}\` (${columns});`,
          });
          continue;
        }

        // Check if index columns changed
        const dbColumns = dbIndex.columns.join(", ");
        const drizzleColumns = getIndexColumns(drizzleIndex).join(", ");
        if (
          dbColumns !== drizzleColumns ||
          dbIndex.unique !== drizzleIndex instanceof UniqueConstraintBuilder
        ) {
          // Drop and recreate index using database values
          changes.push({ change: `DROP INDEX \`${indexName}\` ON \`${tableName}\`;` });
          const columns = dbIndex.columns.map((col) => `\`${col}\``).join(", ");
          const unique = dbIndex.unique ? "UNIQUE " : "";
          changes.push({
            change: `CREATE  ${unique}INDEX if not exists \`${indexName}\` ON \`${tableName}\` (${columns});`,
          });
        }
      }

      // First check foreign keys that exist in database but not in schema
      for (const [fkName, dbFK] of Object.entries(dbTable.foreignKeys)) {
        // Find if this column is referenced in Drizzle schema
        const drizzleFK = metadata.foreignKeys.find(
          (fk) =>
            getForeignKeyName(fk) === fkName ||
            compareForeignKey(fk, { columns: [dbFK.column], unique: false }),
        );

        if (!drizzleFK) {
          // Foreign key exists in database but not in schema - drop it
          changes.push({
            change: `ALTER TABLE \`${tableName}\` ADD CONSTRAINT \`${fkName}\` FOREIGN KEY (\`${dbFK.column}\`) REFERENCES \`${dbFK.referencedTable}\` (\`${dbFK.referencedColumn}\`);`,
          });
          continue;
        }
      }

      // Then check for new foreign keys that exist in schema but not in database
      for (const drizzleForeignKey of metadata.foreignKeys) {
        // Find if this foreign key exists in database
        const isDbFk = Object.keys(dbTable.foreignKeys).find((fk) => {
          let foreignKey = dbTable.foreignKeys[fk];
          return (
            fk === getForeignKeyName(drizzleForeignKey) ||
            compareForeignKey(drizzleForeignKey, { columns: [foreignKey.column], unique: false })
          );
        });

        if (!isDbFk) {
          // Foreign key exists in schema but not in database - create it
          if (drizzleForeignKey) {
            const fkName = getForeignKeyName(drizzleForeignKey);
            if (fkName) {
              changes.push({
                change: `ALTER TABLE \`${tableName}\` DROP FOREIGN KEY  \`${fkName}\`;`,
              });
            } else {
              // @ts-ignore
              const columns = drizzleForeignKey.columns;
              const columnNames = columns?.length
                ? columns.map((c: any) => c.name).join(", ")
                : "unknown columns";
              console.warn(
                `⚠️ Drizzle model for table '${tableName}' does not provide a name for FOREIGN KEY constraint on columns: ${columnNames}`,
              );
            }
          }
        }
      }
    }
  }

  return { changes, preMigrations };
}

/**
 * Updates an existing database migration by generating schema modifications.
 * @param options - Database connection settings and output paths.
 */
export const updateMigration = async (options: any) => {
  try {
    let version = await loadMigrationVersion(options.output);
    const prevVersion = version;

    if (version < 1) {
      console.log(
        `⚠️ Initial migration not found. Run "npx forge-sql-orm migrations:create" first.`,
      );
      process.exit(0);
    }
    version += 1;

    // Create database connection
    const connection = await mysql.createConnection({
      host: options.host,
      port: options.port,
      user: options.user,
      password: options.password,
      database: options.dbName,
    });

    try {
      // Get current database schema
      const dbSchema = await getDatabaseSchema(connection, options.dbName);

      // Import Drizzle schema using absolute path
      const schemaPath = path.resolve(options.entitiesPath, "schema.ts");
      if (!fs.existsSync(schemaPath)) {
        throw new Error(`Schema file not found at: ${schemaPath}`);
      }

      const schemaModule = await import(schemaPath);
      if (!schemaModule) {
        throw new Error(`Invalid schema file at: ${schemaPath}. Schema must export tables.`);
      }

      // Process exported tables
      const drizzleSchema: DrizzleSchema = {};

      // Get all exports that are tables
      const tables = Object.values(schemaModule) as MySqlTable<TableConfig>[];

      tables.forEach((table) => {
        const metadata = getTableMetadata(table);
        if (metadata.tableName) {
          // Convert AnyColumn to DrizzleColumn
          const columns: Record<string, DrizzleColumn> = {};
          Object.entries(metadata.columns).forEach(([name, column]) => {
            columns[name] = {
              type: column.dataType,
              notNull: column.notNull,
              autoincrement: (column as any).autoincrement,
              columnType: column.columnType,
              name: column.name,
              default: (() => {
                if (!column.hasDefault) {
                  return undefined;
                }

                const defaultValue = column.default;

                // If default is an object with toQuery method (e.g., SQL expression)
                if (
                  typeof defaultValue === "object" &&
                  defaultValue !== null &&
                  typeof (defaultValue as any).toQuery === "function"
                ) {
                  return (defaultValue as any).toQuery({}).sql;
                }

                // Otherwise, convert to string
                return String(defaultValue);
              })(),
              getSQLType: () => column.getSQLType(),
            };
          });
          drizzleSchema[metadata.tableName] = columns;
        }
      });

      if (Object.keys(drizzleSchema).length === 0) {
        throw new Error(`No valid tables found in schema at: ${schemaPath}`);
      }

      console.log("Found tables:", Object.keys(drizzleSchema));

      // Generate SQL changes
      const createStatements = filterWithPreviousMigration(
        generateSchemaChanges(drizzleSchema, dbSchema, schemaModule),
        prevVersion,
        options.output,
      );

      if (createStatements.changes.length) {
        // Generate migration file content
        const migrationFile = generateMigrationFile(createStatements, version);

        // Save migration files only if there are actual changes
        if (saveMigrationFiles(migrationFile, version, options.output)) {
          console.log(`✅ Migration successfully updated!`);
        }
        process.exit(0);
      } else {
        console.log(`⚠️ No new migration changes detected.`);
        process.exit(0);
      }
    } finally {
      await connection.end();
    }
  } catch (error) {
    console.error(`❌ Error during migration update:`, error);
    process.exit(1);
  }
};