// Copyright (c) 2001 Hursh Jain (http://www.mollypages.org) 
// The Molly framework is freely distributable under the terms of an
// MIT-style license. For details, see the molly pages web site at:
// http://www.mollypages.org/. Use, modify, have fun !

package fc.web.page;

import java.io.*;
import java.util.*;
import java.net.URL;

import javax.servlet.*;
import javax.servlet.http.*;

import fc.util.*;
import fc.io.*;
import fc.io.fileselectors.*;

/** 
Regression testing since eyeballing parser output just ain't cutting it. 
For developers only, useful when the molly parser is hacked/changed and
we want to ensure that the new parser does not break any existing behavior.
<p>
All regression tests are in the <pre>test</pre> subdirectory (relative to the java
source of this class). These tests exist as *.mp files. This program will
run the parser on each file and a) either check actual output with expected
output and/or b) see if an expected error occurs.
<p>
The expected/canonical output (generated by the good working parser) also
always exists in the <pre>test</pre> subdirectory. The <i>actual</i>
output generated by the latest hacked parser is output in a temporary
directory (the location of which is specified on the command line). The
output are then compared and should be identical.
<p>
The expected output can be regenerated via the <pre>generateExpected</pre>
argument but this should be used by caution. Future/actual output of the
changed/hacked parser is compared with the last good generated expected
output so the expected output should only be updated when the parser is 
in a known working state.

@author hursh jain
*/
public class PageParserTest
{
static  List results = new ArrayList();

public static void main (String args[]) throws Exception
  { 
  Args myargs = new Args(args);
  Log log = Log.getDefault();
  myargs.setUsage("java " + myargs.getMainClassName() 
        + "\n---- Specify ---"
        + "\n   -test   <if specified, run all unit tests with the latest parser>"
        + "\n   -tmpdir <location to a tmp dir used for generated files"
        + "\n----- or ----"
        + "\n   -generateExpected if specified, expected/canonical parser output "
        + "\n                     is generated. Use with caution. The servlet API"
        + "\n                     along with all the molly classes must be on the"
        + "\n                     system classpath for this option to work fully."
    );

  boolean testing  = myargs.flagExists("test");
  boolean generate = myargs.flagExists("generateExpected");
  File  tmpdir = null;
  
  if (! testing && ! generate) 
    myargs.showError();

  if (testing) 
    {
    tmpdir = new File(myargs.getRequired("tmpdir"));
    if (! tmpdir.exists()) {
      log.error("The specified temp directory: " + tmpdir.getAbsolutePath() + " does not exist");
      return;
      }
    }

  Class c = new PageParserTest().getClass();
  URL url = c.getResource("test");
  //System.out.println(url + ";" + url.getFile());  
  File testdir = new File(url.toURI());
  if (! testdir.isDirectory()) {
    log.error(testdir + " is not a directory. This test does not work from within jars. For development, you need to explode the jar");
    return;
    }
    
  log.bug("Regression test directory: " + testdir.getAbsolutePath());

  File[] files = testdir.listFiles(new SuffixSelector(".mp"));
  
  if (files.length == 0)
    log.warn("No *.mp test files found in directory: ", testdir.getAbsolutePath());
    
  Watch wp = new Watch("parse");
  Watch wc = new Watch("compile");
  
  int crap_count = 0;
  int generate_count = 0;
  for (int n = 0; n < files.length; n++) 
    {
    File test = files[n];
    log.bug("Processing file: ", test.getName()); 
        
    //some files are not expected to compile (as part of the test)
    //those files start with "crap..."
    boolean crap = test.getName().toLowerCase().startsWith("crap");
    if (crap) {
      crap_count++;
      }
      
    String result_file_str = test.getName();
    int i = result_file_str.lastIndexOf(".");
    String outbase = result_file_str.substring(0, i);
    String outname = outbase + ".java";
    
    File expected = new File(testdir, outname);
    File out      = new File(tmpdir, outname);
    
    PageParser p;
    PageCompiler pc;
    CharArrayWriter buf = new CharArrayWriter();
    
    //generate
    if (generate) 
      {
      try {
        buf.reset();
        buf.append("Generate: ").append(
          String.format("%-20s",test.getName()));

        wp.start();
        p = new PageParser(testdir, test, expected, outbase);
        p.parse();
        wp.stop();
        
        buf.append(" [parsed in:").
          append(
            String.format("%3s",
            String.valueOf(wp.getTime())))
          .append( " ms, "); 
        //successful parse, no parse exceptions
        //there may be compile time errors though (expected for
        //crap files)
        wc.start();
        pc = new PageCompiler(expected, System.getProperty("java.class.path"), null);
        boolean compiled = pc.compile();
        wc.stop();

        if (! compiled) {
          buf.append(" compile error...possibly expected]"); 
          log.bug(pc.getError());
          }
        else{
          buf.append(" compiled in: ").
            append(
              String.format("%5s",
              String.valueOf(wc.getTime())))
            .append(" ms]"); 
          //remove class file
          File f = new File(testdir, outbase + ".class");
          if (f.exists()) {
            f.delete();
            }
          //compiled ok too.
          generate_count++;
          }
        }
      catch (Exception e) 
        {
        buf.append(" [parse error...possibly expected]"); 
//        if (! crap) { //crap files are expected to have errors
          msg(test.getName(),  "Parse Error: " + e.toString());
//          }
        }

      log.info(buf.toString());
      continue;
      } //end if (generate)
  
    //test
    
    //we need an expected file to compare with
    if (! expected.exists()) 
      {
      if (! crap) {  //wont exist for crap files cause parse error
        msg(test.getName(), "FAILED [expected file: " +  expected.getAbsolutePath() + " does not exist]");
        continue;
        }
      }
      
    p = new PageParser(testdir, test, out, outbase);
    
    try {
      p.parse();
      //crap files will cause a parse exception
      //if here, then parse successful
      if (! compare(expected, out)) {
        msg(test.getName(), "FAIL [expected != actual]");
        }
      else{
        msg(test.getName(), "OK");
        }
      }
    catch (Exception e) {
      if (crap) {
        //we wanted the expected parse exception
        msg(test.getName(), "OK");
        }
      else{
        msg(test.getName(), "FAIL [ParseException] " + e.toString());
        }
      }
    
    } //end for loop
  
  if (generate) {
    System.out.println();
    System.out.println((files.length - crap_count) + " total (non-crap) *.mp files in " + testdir.getAbsolutePath());
    System.out.println(generate_count + " expected files were generated.");
    }
  
  //print results
  System.out.println();
  TablePrinter.PrintConfig pconfig = new TablePrinter.PrintConfig();
  pconfig.setAutoFit(false).setPrintBorders(true).setCellPadding(1);
  if (generate) {
    pconfig.setCellWidthForColumn(1,55);
    System.out.println("The following errors are expected!");
    }
  TablePrinter printer = new TablePrinter(2, System.out, pconfig);
  printer.startTable();
  for (int n = 0; n < results.size(); n++) {
    printer.startRow();
    Object[] arr = (Object[]) results.get(n);
    printer.printCell(arr[0].toString());
    printer.printCell(arr[1].toString());
    printer.endRow();
    }
  printer.endTable();
  }

static void msg(Object testName, Object result)
  {
  results.add(new Object[] {testName, result});
  }

static boolean compare(File expected, File output) throws Exception
  {
  if (! output.exists())
    return false;
    
  byte[] expected_b = IOUtil.fileToByteArray(expected);
  byte[] output_b   = IOUtil.fileToByteArray(output);
  
  return Arrays.equals(expected_b, output_b);
  }

}