/*
 * Public Domain Software
 *
 * I (Matthias Ladkau) am the author of the source code in this file.
 * I have placed the source code in this file in the public domain.
 *
 * For further information see: http://creativecommons.org/publicdomain/zero/1.0/
 */

package parser

import (
	"encoding/json"
	"flag"
	"fmt"
	"os"
	"testing"
)

// Main function for all tests in this package

func TestMain(m *testing.M) {
	flag.Parse()

	res := m.Run()

	// Check if all nodes have been tested

	for _, n := range astNodeMap {
		if _, ok := usedNodes[n.Name]; !ok {
			fmt.Println("Not tested node: ", n.Name)
		}
	}

	// Check if all nodes have been pretty printed

	for k := range prettyPrinterMap {
		if _, ok := usedPrettyPrinterNodes[k]; !ok {
			fmt.Println("Not tested pretty printer: ", k)
		}
	}

	os.Exit(res)
}

// Used nodes map which is filled during unit testing. Prefilled with tokens which
// will not be generated by the parser
//
var usedNodes = map[string]bool{
	NodeEOF: true, // Only used as end term
	"":      true, // No node e.g. semicolon - These nodes should never be part of an AST
}

func UnitTestParse(name string, input string) (*ASTNode, error) {
	n, err := ParseWithRuntime(name, input, &DummyRuntimeProvider{})

	// TODO Test pretty printing

	// Test AST serialization

	if err == nil {
		var unmarshaledJSONObject map[string]interface{}

		astString, err := json.Marshal(n.ToJSONObject())
		if err != nil {
			return nil, fmt.Errorf("Could not marshal AST: %v", err)
		}

		if err := json.Unmarshal(astString, &unmarshaledJSONObject); err != nil {
			return nil, fmt.Errorf("Could not unmarshal JSON object: %v", err)
		}

		unmarshaledAST, err := ASTFromJSONObject(unmarshaledJSONObject)
		if err != nil {
			return nil, fmt.Errorf("Could not create AST from unmarshaled JSON object: %v", err)
		}

		// String compare the ASTs
		if ok, msg := n.Equals(unmarshaledAST); !ok {
			return nil, fmt.Errorf(
				"Parsed AST is different from the unmarshaled AST.\n%v\n",
				msg)
		}
	}

	return n, err
}

// Used nodes map which is filled during unit testing. Prefilled with tokens which
// will not be generated by the parser
//
var usedPrettyPrinterNodes = map[string]bool{}

func UnitTestPrettyPrinting(input, astOutput, ppOutput string) error {
	var visitAST func(*ASTNode)

	astres, err := ParseWithRuntime("mytest", input, &DummyRuntimeProvider{})
	if err != nil || fmt.Sprint(astres) != astOutput {
		return fmt.Errorf("Unexpected parser output:\n%v expected was:\n%v Error: %v", astres, astOutput, err)
	}

	visitAST = func(n *ASTNode) {

		// Make the encountered node as used

		numChildren := len(n.Children)
		if numChildren > 0 {
			usedPrettyPrinterNodes[fmt.Sprintf("%v_%v", n.Name, numChildren)] = true
		} else {
			usedPrettyPrinterNodes[n.Name] = true
		}

		for _, c := range n.Children {
			visitAST(c)
		}
	}

	visitAST(astres)

	ppres, err := PrettyPrint(astres)
	if err != nil || ppres != ppOutput {
		return fmt.Errorf("Unexpected result: %v (expected: %v) error: %v", ppres, ppOutput, err)
	}

	// Make sure the pretty printed result is valid and gets the same parse tree

	astres2, err := ParseWithRuntime("mytest", ppres, &DummyRuntimeProvider{})
	if err != nil || fmt.Sprint(astres2) != astOutput {
		return fmt.Errorf("Unexpected parser output from pretty print string:\n%v expected was:\n%v Error: %v", astres2, astOutput, err)
	}

	return nil
}

// Helper objects

type DummyRuntimeProvider struct {
}

func (d *DummyRuntimeProvider) Runtime(n *ASTNode) Runtime {

	// Make the encountered node as used

	usedNodes[n.Name] = true

	return nil
}