package parser

import (
	"go/ast"

	"golang.org/x/tools/go/packages"
)

func (p *Parser) getApplicationVariableName(pkg *packages.Package, wailsImportName string) (string, bool) {

	var applicationVariableName = ""

	// Iterate through the whole package looking for the application name
	for _, fileAst := range pkg.Syntax {
		ast.Inspect(fileAst, func(n ast.Node) bool {
			// Parse Assignments looking for application name
			if assignStmt, ok := n.(*ast.AssignStmt); ok {

				// Check the RHS is of the form:
				//   `app := wails.CreateApp()` or
				//   `app := wails.CreateAppWithOptions`
				for _, rhs := range assignStmt.Rhs {
					ce, ok := rhs.(*ast.CallExpr)
					if !ok {
						continue
					}
					se, ok := ce.Fun.(*ast.SelectorExpr)
					if !ok {
						continue
					}
					i, ok := se.X.(*ast.Ident)
					if !ok {
						continue
					}
					// Have we found the wails import name?
					if i.Name == wailsImportName {
						// Check we are calling a function to create the app
						if se.Sel.Name == "CreateApp" || se.Sel.Name == "CreateAppWithOptions" {
							if len(assignStmt.Lhs) == 1 {
								i, ok := assignStmt.Lhs[0].(*ast.Ident)
								if ok {
									// Found the app variable name
									applicationVariableName = i.Name
									return false
								}
							}
						}
					}
				}
			}
			return true
		})
	}
	return applicationVariableName, applicationVariableName != ""
}