extension.js

// The module 'vscode' contains the VS Code extensibility API
// Import the module and reference it with the alias vscode in your code below
const vscode = require('vscode');

// this method is called when your extension is activated
// your extension is activated the very first time the command is executed

String.toTitle = function(str) {
	if(str && str.length > 0) {
		return str.charAt(0).toUpperCase() + str.slice(1);
	}

	return "";
}

function makeTitle(title) {
	let retval = ""
	if(title.indexOf("_") > -1) {
		const parts = title.split("_");
		parts.forEach(val => {
			retval+=makeTitle(val.toString())
		})
	} else {
		if(title.length <= 3) {
			retval = title.toUpperCase()
		} else {
			retval = String.toTitle(title)
		}
	}

	return retval
}

/**
 * @param {vscode.ExtensionContext} context
 */
function activate(context) {
	// The command has been defined in the package.json file
	// Now provide the implementation of the command with  registerCommand
	// The commandId parameter must match the command field in package.json
	let disposable = vscode.commands.registerCommand('extension.ddl-2-go-struct', function () {
		var editor = vscode.window.activeTextEditor;
		if (!editor) {
			return; // No open text editor
		}

		var selection = editor.selection;
		var text = editor.document.getText(selection);
		if(text.length===0) {
			return;
		}
		const sqlLines = text.split('\n');

		let structCodes = [];
		sqlLines.forEach(line => {
			line = line.trim();
			if(line.length==0){
				return;
			}

			try {
				const rs = /create\stable\s"?([a-zA-Z\.\_]+)"?\s?\(?/igm.exec(line)
				if(rs != null) {
					let tableTitle = rs[1];
					tableTitle = tableTitle.replace(/([a-zA-Z]+\.)/, "")
					tableTitle = tableTitle.replace(/^(t\_)/, "")
					structCodes = [...structCodes, "\n// " + makeTitle(tableTitle) + " --"]
					structCodes = [...structCodes, "type " + makeTitle(tableTitle) + " struct {"]
				}

				if(/[a-zA-Z\_]+\s(text|character|inet)/gi.exec(line) != null) {
					const colunmName = line.split(" ")[0]
					if(/not\snull/gi.exec(line) == null) {
						structCodes = [...structCodes, "\t" + makeTitle(colunmName) + "\tsql.NullString\t`db:\""+colunmName+"\"`"]
					} else {
						structCodes = [...structCodes, "\t" + makeTitle(colunmName) + "\tstring\t`db:\""+colunmName+"\"`"]
					}
				}
				
				if(/[a-zA-Z\_]+\s(serial|integer|bigserial|bigint|smallint)/gi.exec(line) != null) {
					const colunmName = line.split(" ")[0]
					if(/not\snull/gi.exec(line) == null) {
						structCodes = [...structCodes, "\t" + makeTitle(colunmName) + "\tsql.NullInt64\t`db:\""+colunmName+"\"`"]
					} else {
						structCodes = [...structCodes, "\t" + makeTitle(colunmName) + "\tint64\t`db:\""+colunmName+"\"`"]
					}
				}
				
				if(/[a-zA-Z\_]+\s(float|numeric)/gi.exec(line) != null) {
					const colunmName = line.split(" ")[0]
					if(/not\snull/gi.exec(line) == null) {
						structCodes = [...structCodes, "\t" + makeTitle(colunmName) + "\tsql.NullFloat64\t`db:\""+colunmName+"\"`"]
					} else {
						structCodes = [...structCodes, "\t" + makeTitle(colunmName) + "\tfloat64\t`db:\""+colunmName+"\"`"]
					}
				}

				if(/[a-zA-Z\_]+\s(boolean)/gi.exec(line) != null) {
					const colunmName = line.split(" ")[0]
					if(/not\snull/gi.exec(line) == null) {
						structCodes = [...structCodes, "\t" + makeTitle(colunmName) + "\tsql.NullBool\t`db:\""+colunmName+"\"`"]
					} else {
						structCodes = [...structCodes, "\t" + makeTitle(colunmName) + "\tbool\t`db:\""+colunmName+"\"`"]
					}
				}

				if(/[a-zA-Z\_]+\s(json)/gi.exec(line) != null) {
					const colunmName = line.split(" ")[0]
					structCodes = [...structCodes, "\t" + makeTitle(colunmName) + "\tmap[string]interface{}\t`db:\""+colunmName+"\"`"]
				}
				
				if(/[a-zA-Z\_]+\s(timestamp)/gi.exec(line) != null) {
					const colunmName = line.split(" ")[0]
					structCodes = [...structCodes, "\t" + makeTitle(colunmName) + "\t*time.Time\t`db:\""+colunmName+"\"`"]
				}
				
				if(/\)\;/gi.exec(line) != null) {
					structCodes = [...structCodes, "}"]
				}
			} catch (error) {
				console.error(error)
			}
		});
		
		editor.edit(builder => {
			builder.replace(selection, structCodes.join("\n"))
		})
	});

	context.subscriptions.push(disposable);
}
exports.activate = activate;

// this method is called when your extension is deactivated
function deactivate() {}

module.exports = {
	activate,
	deactivate
}