class TreeMLBuilder {
    def sb = new StringBuilder()

    def declarations = [:]

    def methodMissing(String name, args) {
        println "methodMissing $name, args : $args, length : $args.length"

        switch (name) {
            case 'tree':
                assert args.length == 1 && args[0] instanceof Closure
                args[0].delegate = this
                sb.append '<tree>'
                args[0]()
                sb.append '</tree>'
                break

            case 'declarations':
                assert args.length == 1 && args[0] instanceof Closure
                args[0].delegate = this
                sb.append '<declarations>'
                args[0]()
                sb.append '</declarations>'
                break

            case 'attributeDecl':
                assert args.length == 1 && args[0] instanceof HashMap && args[0].size() == 2
                assert args.name && args.type
                declarations."${args.name[0]}" = args.type[0]
                sb.append "<attributeDecl name='${args.name[0]}' type='${args.type[0]}'/>"
                break

            case 'branch':
                assert args.length == 1 && args[0] instanceof Closure
                args[0].delegate = this
                sb.append '<branch>'
                args[0]()
                sb.append '</branch>'
                break

            case 'leaf':
                assert args.length == 1 && args[0] instanceof Closure
                args[0].delegate = this
                sb.append '<leaf>'
                args[0]()
                sb.append '</leaf>'
                break                

            default:
                // Dans le contexte d'une branche ou d'un noeud
                println "default : $name"
                if (declarations."$name") {
                    assert args.length == 1
                    sb.append "<attribute name='$name' value='${args[0]}'/>"
                }
        }

    }

    def build()  {
        sb.toString()
    }

}

def builder = new TreeMLBuilder()
builder.tree {
    declarations {
        attributeDecl(name: 'nom', type: 'String')
    }    
 
    branch {
        nom 'Groovy'

        branch {
            nom 'Language'
            
            branch {
                nom 'Literals'

                leaf {
                    nom 'Strings / RegEx'
                }

                leaf {
                    nom 'Lists / Maps / Ranges'
                }

                leaf {
                    nom 'Closures'
                }
            }

            branch {
                nom 'Every is an object'

                leaf {
                    nom 'Object operators'
                }

                leaf {
                    nom 'Multimethods'
                }

                leaf {
                    nom 'GroovyBeans'
                }
            }

            branch {
                nom 'Meta Object Protocol'

                leaf {
                    nom 'Method interception'
                }

                leaf {
                    nom 'Category use (Mixin)'
                }

                leaf {
                    nom 'Dynamic methods and properties'
                }
            }

            branch {
                nom 'Control Flow'

                leaf {
                    nom 'Groovy Truth'
                }

                leaf {
                    nom 'Switch'
                }

                leaf {
                    nom 'Advanced operators'
                }

                leaf {
                    nom 'GPath'
                }

                leaf {
                    nom 'Iterations'
                }
            }

            branch {
                nom 'Execution'

                leaf {
                    nom 'Scriptablility'
                }

                leaf {
                    nom 'Hot class reloading'
                }
            }
        }

        branch {
            nom 'Library'

            leaf {
                nom 'SQL'
            }

            leaf {
                nom 'XML'
            }

            leaf {
                nom 'Swing'
            }

            leaf {
                nom 'Ant'
            }

            leaf {
                nom 'Templates'
            }

            leaf {
                nom 'Groovlets'
            }

            leaf {
                nom 'Stubs and Mocks'
            }
        }

        branch {
            nom 'GDK'

            leaf {
                nom 'Object Inspection'
            }

            branch {
                nom 'Groovy-aware methods'

                leaf {
                    nom 'Strings'
                }

                leaf {
                    nom 'Lists'
                }

                leaf {
                    nom 'Maps'
                }
            }

            leaf {
                nom 'Files and I/O'
            }

            leaf {
                nom 'Threads and Processes'
            }
        }
    } 
}

builder.build()