with GNAT.Command_Line;
with GNAT.Strings;
with Ada.Command_Line;
with Ada.Text_IO; use Ada.Text_IO;
with Ada.Directories;
with Ada.Strings.Unbounded;
with Simple_Time;
with CSV;
with Candidates;


procedure STV is


    package ACom renames Ada.Command_Line;
    package GCom renames GNAT.Command_Line;
    package GStr renames GNAT.Strings;
    package File renames Ada.Directories;
    package SU renames Ada.Strings.Unbounded;


    use type File.File_Kind;
    use type SU.Unbounded_String;


    Config : GCom.Command_Line_Configuration;


    Further_Help : String := "Try ""stv --help"" for more information.";


    Verbose         : aliased Boolean;
    Version         : aliased Boolean;
    Help            : aliased Boolean;
    Candidate_File  : aliased GStr.String_Access;
    Preference_File : aliased GStr.String_Access;
    Output_Dir      : aliased GStr.String_Access;
    Number_To_Elect : aliased Integer;
    State_String    : aliased GStr.String_Access;


    type State_Name is (ACT, NT, TAS, SA, WA, VIC, QLD, NSW);
    State : State_Name;


    Start_Time, Finish_Time : Simple_Time.Time;
    Main_Log, Log_Msg : SU.Unbounded_String;


begin


    GCom.Define_Switch
           (Config => Config, Output      => Verbose'Access,
            Switch => "-v",   Long_Switch => "--verbose",
            Help   => "chatty output on stderr");

    GCom.Define_Switch
           (Config => Config, Output      => Version'Access,
            Switch => "-V",   Long_Switch => "--version",
            Help   => "show version number");

    --  technically not required, but included so
    --  it will show up in the help output
    GCom.Define_Switch
           (Config => Config, Output      => Help'Access,
            Switch => "-h",   Long_Switch => "--help",
            Help   => "show this help information");

    GCom.Define_Switch
           (Config => Config, Output      => Candidate_File'Access,
            Switch => "-c:",  Long_Switch => "--candidates=",
            Help   => ".csv file containing AEC candidate data");

    GCom.Define_Switch
           (Config => Config, Output      => Preference_File'Access,
            Switch => "-p:",  Long_Switch => "--preference=",
            Help   => ".csv file containing AEC formal preferences");

    GCom.Define_Switch
           (Config => Config, Output      => Output_Dir'Access,
            Switch => "-o:",  Long_Switch => "--outdir=",
            Help   => "new directory to output count logging");

    GCom.Define_Switch
           (Config => Config, Output      => Number_To_Elect'Access,
            Switch => "-e:",  Long_Switch => "--elect=",
            Help   => "number of candidates to elect");

    GCom.Define_Switch
           (Config => Config, Output      => State_String'Access,
            Switch => "-s:",  Long_Switch => "--state=",
            Help   => "state or territory the data corresponds to");


    GCom.Set_Usage
           (Config => Config,
            Usage  => "[switches]",
            Help   => "Note that the -c, -p, -o, -e, -s options are all" & ASCII.LF &
                        "required for normal operation." & ASCII.LF);


    --  parse options
    begin
        GCom.Getopt (Config);
    exception
        when GCom.Exit_From_Command_Line =>
            ACom.Set_Exit_Status (ACom.Failure);
            return;
        when GCom.Invalid_Switch =>
            ACom.Set_Exit_Status (ACom.Failure);
            return;
    end;


    --  version display functionality
    if Version then
        Put_Line ("Australian STV Counter v0.2");
        ACom.Set_Exit_Status (ACom.Failure);
        return;
    end if;


    --  check candidate data option is valid
    if Candidate_File.all = "" then
        Put_Line ("Candidate data file not provided." & ASCII.LF & Further_Help);
        ACom.Set_Exit_Status (ACom.Failure);
        return;
    end if;
    if not File.Exists (Candidate_File.all) then
        Put_Line ("Candidate data file does not exist." & ASCII.LF & Further_Help);
        ACom.Set_Exit_Status (ACom.Failure);
        return;
    end if;
    if File.Kind (Candidate_File.all) /= File.Ordinary_File then
        Put_Line ("Candidate data file name appears to refer to a directory or special file." & ASCII.LF & Further_Help);
        ACom.Set_Exit_Status (ACom.Failure);
        return;
    end if;


    --  check preference data option is valid
    if Preference_File.all = "" then
        Put_Line ("Preference data file not provided." & ASCII.LF & Further_Help);
        ACom.Set_Exit_Status (ACom.Failure);
        return;
    end if;
    if not File.Exists (Preference_File.all) then
        Put_Line ("Preference data file does not exist." & ASCII.LF & Further_Help);
        ACom.Set_Exit_Status (ACom.Failure);
        return;
    end if;
    if File.Kind (Preference_File.all) /= File.Ordinary_File then
        Put_Line ("Preference data file name appears to refer to a directory or special file." & ASCII.LF & Further_Help);
        ACom.Set_Exit_Status (ACom.Failure);
        return;
    end if;


    --  check output directory option is valid
    if Output_Dir.all = "" then
        Put_Line ("Output logging directory not provided." & ASCII.LF & Further_Help);
        ACom.Set_Exit_Status (ACom.Failure);
        return;
    end if;
    if File.Exists (Output_Dir.all) then
        Put_Line ("Output logging directory already exists." & ASCII.LF & Further_Help);
        ACom.Set_Exit_Status (ACom.Failure);
        return;
    end if;


    --  check state option is valid
    begin
        State := State_Name'Value (State_String.all);
    exception
        when Constraint_Error =>
            Put_Line ("Invalid State/Territory or State/Territory not provided." & ASCII.LF & Further_Help);
            ACom.Set_Exit_Status (ACom.Failure);
            return;
    end;


    --  set up logging
    --File.Create_Directory (Output_Dir.all);
    Start_Time := Simple_Time.Now;
    Main_Log := SU.To_Unbounded_String (Output_Dir.all & "/" & "log.txt");
    Log_Msg := SU.To_Unbounded_String ("Started election count at " & Simple_Time.To_String (Start_Time));
    Put_Line (SU.To_String (Log_Msg));


    Finish_Time := Simple_Time.Now;


end STV;