#include <iostream>
#include <fstream>
#include <time.h>
#include <unistd.h>
#include <getopt.h>

#include <TROOT.h>
#include <TRint.h>
#include <TSystem.h>

#include "ICOMETLog.hxx"
#include "ICOMETInput.hxx"
#include "ICOMETOutputMerged.hxx"
#include "IInputFileList.hxx"

void usage(void) {
    std::cout 
    <<"Usage: oaEvent_concatenate-files.exe [options] files\n"
      "  where file specifier is the path to a list of oaEvent files\n"
      "  <filepath>/<oaeventfile>\n\n"
      "The specified files are concatenated into one large file by merging the event \n"
      "trees. Records of original file content are saved using IEntryLists, which \n"
      "are stored in the new merged output file.\n\n"
      "Options: \n"
      "    -I    Text file containing a list of input oaEvent files.  Each line must\n"                  
      "          match one of the following forms. \n"                  
      "            filename \n"
      "            filename root \n"
      "          Note, this has only been tested on ROOT files.\n\n"                  
      "    -o    Name of the output file\n\n"
      "    -b    Flag to allow bad files to be skipped\n\n"
      "    -L    Flag disabling file list log being printed" << std::endl;
}

int main(int argc, char **argv) {
    // Get the default options
    COMET::IInputFileList inputFiles;
    inputFiles.SetSkipBadFiles(false);
    std::string fOutFileName = "mergedFiles.root";
    bool printFilelistLog = true;
    // Lets count how many events we merge
    int nEventsMerged = 0;

    // Set the options
    int c;
    while ((c = getopt(argc, argv, "I:o:bLh")) != -1)
        switch (c){
            // List of files from an input file list
            case 'I':
                if(!inputFiles.ReadListFromFile(optarg)){
                    COMETError("Problem obtaining input list from file.");
                    return 1;
                }
                break;
            // Choose the output name
            case 'o':
                fOutFileName= optarg;
                break;
            // Suppress printing the file list log
            case 'L':
                printFilelistLog = false;
                break;
            // Allow bad files to be skipped
            case 'b':
                inputFiles.SetSkipBadFiles(false);
                break;
            // Print the help menu
            case 'h':
                usage();
                return 0;
            // Let getopt deal with the rest
            case '?':
                return 1;
            default:
                abort();
        }

    // Prepare the input files
    for(int i = optind;i<argc; ++i) {
        inputFiles.AddRootFile(argv[i]);
    }

    //Configure COMETLog levels from input config file
    TString configPath = "${PWD}/cometlog.config";
    gSystem->ExpandPathName(configPath);
    COMET::ICOMETLog::Configure(configPath.Data());
    
    // Open the output
    COMET::ICOMETOutputMerged* mergedFile = 
        new COMET::ICOMETOutputMerged(fOutFileName.c_str(), "CREATE");
    // Declare the output list file and open it if we need it
    std::ofstream fileListLog;
    if (printFilelistLog) {
        // Delare the name of the output file list log
        std::string fileListLogName;
        // Get the basename of the file minus the extension
        std::string outBaseName = gSystem->BaseName(fOutFileName.c_str());
        std::string outDirName = gSystem->DirName(fOutFileName.c_str());
        outDirName.append("/");
        size_t lastdot = outBaseName.find_last_of(".");
        // If it has no extention, just add the correct suffix
        if (lastdot == std::string::npos) fileListLogName = fOutFileName + "_listlog.txt";
        // Otherwise, strip the extension, and add the correct suffix
        else fileListLogName = outDirName + outBaseName.substr(0, lastdot) + "_listlog.txt"; 
        fileListLog.open(fileListLogName.c_str());
    }
    // Open up the input files
    while (inputFiles.OpenNextFile()){
        // Get the next input file
        COMET::ICOMETInput* fInputFile = 
            dynamic_cast<COMET::ICOMETInput*>(inputFiles.GetCurrentFile());
        // Add this input file
        mergedFile->AddFile(fInputFile);
        if (printFilelistLog) fileListLog << fInputFile->GetFilename() << "\n";
        // Add the number of entries added
        nEventsMerged += fInputFile->GetEventsInFile();
        inputFiles.CloseFile();
    }
    // Close the merged file
    mergedFile->Close();
    if (printFilelistLog) fileListLog.close();
    // Recored the number of events merged
    COMETLog("Number of Events Merged : " << nEventsMerged);
    return 0;
}