
// SQLite3: Column Builder & Compiler
// -------
import inherits from 'inherits';
import SchemaCompiler from '../../../schema/compiler';

import { some } from 'lodash'

// Schema Compiler
// -------

function SchemaCompiler_SQLite3() {
  SchemaCompiler.apply(this, arguments);
}
inherits(SchemaCompiler_SQLite3, SchemaCompiler);

// Compile the query to determine if a table exists.
SchemaCompiler_SQLite3.prototype.hasTable = function(tableName) {
  const sql =
    `select * from sqlite_master ` +
    `where type = 'table' and name = ${this.formatter.parameter(tableName)}`;
  this.pushQuery({ sql, output: resp => resp.length > 0 });
};

// Compile the query to determine if a column exists.
SchemaCompiler_SQLite3.prototype.hasColumn = function(tableName, column) {
  this.pushQuery({
    sql: `PRAGMA table_info(${this.formatter.wrap(tableName)})`,
    output(resp) {
      return some(resp, {name: column});
    }
  });
};

// Compile a rename table command.
SchemaCompiler_SQLite3.prototype.renameTable = function(from, to) {
  this.pushQuery(`alter table ${this.formatter.wrap(from)} rename to ${this.formatter.wrap(to)}`);
};

export default SchemaCompiler_SQLite3;
