package pt.utl.ist.fenix.tools.scripts;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.SortedMap;
import java.util.TreeMap;
import java.util.Map.Entry;

import org.apache.commons.lang.StringUtils;

import pt.utl.ist.fenix.tools.util.FileUtils;
import pt.utl.ist.fenix.tools.util.StringAppender;

public class JoinSQLScripts {

    public static void main(String[] args) {
        final String dirName = args[0];
        final String fromDateString = args[1];
        final String outputFile = args[2];

        final File dir = new File(dirName);
        final SortedMap<String, File> directoryTree = new TreeMap<String, File>();

        loadDirectories(directoryTree, dir);

        System.out.println("Loaded " + directoryTree.size() + " directories, from " + directoryTree.firstKey() + " to " + directoryTree.lastKey());
        directoryTree.put("Z_BaseDir", dir);

        try {
            final List<String> sqlScripts = loadSQLScripts(directoryTree, "R" + fromDateString);
            final PrintWriter printWriter = constructRunPrintWriter(outputFile);
            for (final String sqlFilename : sqlScripts) {
                printWriter.append("executeWithTempFile \"");
                printWriter.append(sqlFilename);
                printWriter.append("\" ");
                printWriter.append(sqlFilename);
                printWriter.append('\n');
            }
            printWriter.close();
        } catch (IOException e) {
            e.printStackTrace();
        }

        System.exit(0);
    }

    private static PrintWriter constructRunPrintWriter(String outputFile) throws FileNotFoundException {
        final PrintWriter printWriter = new PrintWriter(outputFile);

        printWriter.append("#!/bin/sh\n");
        printWriter.append("# -----------------------------------------------------------------------------\n");
        printWriter.append("#\n");
        printWriter.append("#   Runs sql scripts to update database from previous release.\n");
        printWriter.append("#\n");
        printWriter.append("# -----------------------------------------------------------------------------\n");
        printWriter.append("#\n");
        printWriter.append("\n");
        printWriter.append("DB=$1\n");
        printWriter.append("USER=$2\n");
        printWriter.append("DB_HOST=$3\n");
        printWriter.append("INSTITUTION=`grep \"institution=\" ../../build.properties | cut -d '=' -f2`\n");
        printWriter.append("\n");
        printWriter.append("echo Using host=$DB_HOST\n");
        printWriter.append("echo Using database: $DB\n");
        printWriter.append("echo Using user $USER:\n");
        printWriter.append("echo Institution: $INSTITUTION\n");
        printWriter.append("function execute() {\n");
        printWriter.append("\tif [ -z $3 ]\n");
        printWriter.append("\tthen\n");
        printWriter.append("\techo $1\n");
        printWriter.append("\tmysql -u$USER -f -h$DB_HOST --default-character-set=latin1 $DB < $2 \n");
        printWriter.append("\techo\n");
        printWriter.append("\telse\n");
        printWriter.append("\tif [ \"$INSTITUTION\" == \"$3\" ]\n");
        printWriter.append("\tthen\n");
        printWriter.append("\techo $1\n");
        printWriter.append("\tmysql -u$USER -f -h$DB_HOST --default-character-set=latin1 $DB < $2 \n");
        printWriter.append("\techo\n");
        printWriter.append("\tfi\n");
        printWriter.append("\tfi\n");
        printWriter.append("}\n");
        printWriter.append("\n");
        printWriter.append("function executeWithTempFile() {\n");
        printWriter.append("\techo $1\n");
        printWriter.append("\tmysql -u$USER -f -h$DB_HOST --default-character-set=latin1 $DB < $2 > tmp.sql\n");
        printWriter.append("\tmysql -u$USER -f -h$DB_HOST --default-character-set=latin1 $DB < tmp.sql\n");       
        printWriter.append("\trm tmp.sql\n");
        printWriter.append("\techo\n");
        printWriter.append("}\n");
        printWriter.append("\n");
        printWriter.append("\n");

        return printWriter;
    }

    private static void loadDirectories(final SortedMap<String,File> directoryTree, final File dir) {
        for (final File file : dir.listFiles()) {
            if (file.isDirectory() && file.getName().startsWith("R")) {
                final String filename = file.getName();
                if (filename.length() == 11) {
                    directoryTree.put(filename, file);
                } else {
                    loadDirectories(directoryTree, file);
                }
            }
        }
    }

    private static List<String> loadSQLScripts(final SortedMap<String, File> directoryTree, final String fromDirName) throws IOException {
        final List<String> sqlScripts = new ArrayList<String>();
        for (final Entry<String, File> dirEntry : directoryTree.entrySet()) {
            //System.out.println("Processing dir: " + dirEntry.getKey());
            final File runFile = findFile(dirEntry.getValue(), "run");
            if (fromDirName.compareTo(dirEntry.getKey()) <= 0) {
                if (runFile == null) {
                    System.out.println("No run file found in directory: " + dirEntry.getKey());
                    for (final File file : dirEntry.getValue().listFiles()) {
                        if (file.getName().endsWith(".sql")) {
                            sqlScripts.add(file.getAbsolutePath());
                        }
                    }
                } else {
                    addSpecifiedSQLScripts(sqlScripts, runFile);
                }
            }
        }
        return sqlScripts;
    }

    private static void addSpecifiedSQLScripts(final List<String> sqlScripts, final File runFile) throws IOException {
        final String dirName = runFile.getParentFile().getAbsolutePath();
        final String contents = FileUtils.readFile(runFile.getAbsolutePath());
        final String[] lines = contents.split("\n");
        for (final String line : lines) {
            final String sqlFilename = findSQLFilename(line);
            if (sqlFilename != null && sqlFilename.length() > 0) {
                final String absoluteFilename = StringAppender.append(dirName, "/", sqlFilename);
                final File file = new File(absoluteFilename);
                if (file.exists()) {
                    sqlScripts.add(absoluteFilename);
                }
            }
        }
    }

    private static String findSQLFilename(String line) {
        final String trimmedLine = line.trim();
        if (line.startsWith("mysql")) {
            final String suffix = StringUtils.substringAfterLast(trimmedLine, "<").trim();
            final int posOfOutPipe = suffix.indexOf('>');
            return posOfOutPipe > 0 ? suffix.substring(0, posOfOutPipe).trim() : suffix;
        } else if (line.startsWith("execute")) {
            final String fullSuffix = StringUtils.substringAfterLast(trimmedLine, "\"").trim();
            final int posOfOutPipe = fullSuffix.indexOf('>');
            return posOfOutPipe > 0 ? fullSuffix.substring(0, posOfOutPipe).trim() : fullSuffix;
        }
        return null;
    }

    private static File findFile(File dir, String filename) {
        for (final File file : dir.listFiles()) {
            if (file.getName().equals(filename)) {
                return file;
            }
        }
        return null;
    }

}