import java.util.Scanner;
import java.io.File;
import java.io.FileNotFoundException;


/* Java application that is intended to make use of the Election class
** for the purpose of testing its features.
**
** In summary, this program reads partial election results from one 
** "vote-counts" file, processes the ballots described in another file,
** and then writes the updated (possibly still partial) election results
** to another "vote-counts" file.  (The two "vote-counts" files could be
** the same file, in which case its original contents will be overwritten.)
**
** The names of the three files (minus their assumed ".txt" extensions)
** must be passed to this program via command-line arguments.
**
** The two vote-counts files begin with a record indicating the number
** of candidates.  Each subsequent record contains the name of a
** candidate, optionally followed by a colon and a vote count.  (If the
** colon and vote count are absent, the intent is that the vote count
** is zero.)
** 
** Each record in the ballots file is the name of a candidate and 
** represents a vote for that candidate.
**
** Author: R. McCloskey
** Date: November 2024
*/
public class ElectionApp {

   public static void main(String[] args) throws FileNotFoundException {
      // Assign the three command line arguments, which name the two 
      // input files and the output file, to variables with meaningful names.
      String voteCountsBeforeFileName = args[0] + ".txt";
      String ballotsFileName = args[1] + ".txt";
      String voteCountsAfterFileName = args[2] + ".txt";

      // Create an Election object from the input vote-counts file,
      Election election = new Election(voteCountsBeforeFileName);

      // Process the ballots in the ballots file. 
      Scanner ballotsInput = new Scanner(new File(ballotsFileName));
      while (ballotsInput.hasNextLine()) {
         String s = ballotsInput.nextLine().trim();
         System.out.print("Processing vote for " + s);
         if (election.recordVoteFor(s)) {
            System.out.println("; vote count: " + election.numVotesFor(s) +
                               "; rank: " + election.rankOf(s));
         }
         else {
            System.out.println(": not counted (no such candidate)");
         };
      }

      // Print the updated election standings. 
      System.out.println("\nElection standings:");
      election.displayStandings();

      // Write the updated election standings to the output vote-counts
      // file, which could possibly be used as input during a later run of
      // this program when more ballots are available to be processed.
      election.writeToFile(voteCountsAfterFileName);
   }

}