unit Newsletter;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes,
  Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.Grids, Vcl.StdCtrls, System.Generics.Collections;

type
  TNewsletterFrame = class(TFrame)
    GroupBox1: TGroupBox;
    SGCandidate: TStringGrid;
    procedure FrameEnter(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

implementation

{$R *.dfm}

uses BidirectionalCandidate, BidirectionalParty, Candidate, CountyNumber, Main;

const
    HEADER_PARTYNAME = 'Название партии';
    HEADER_AMOUNTREQUEST = 'Кол-во заявок';
    HEADER_MIDDLEAGE = 'Средний возраст кандидатов';
    HEADER_FREQUENTPROFESSION = 'Частая профессия';

procedure ClearStringGrid(SG : TStringGrid);
var
    I, J : Integer;
begin
    for I := 0 to SG.RowCount - 1 do
    begin
        SG.Rows[I].Clear;
    end;
end;

procedure FillHeadersSG(SGCandidate : TStringGrid);
begin
    SGCandidate.Cells[0,0] := HEADER_PARTYNAME;
    SGCandidate.Cells[1,0] := HEADER_AMOUNTREQUEST;
    SGCandidate.Cells[2,0] := HEADER_MIDDLEAGE;
    SGCandidate.Cells[3,0] := HEADER_FREQUENTPROFESSION;
    SGCandidate.ColWidths[0] := 300;
    SGCandidate.ColWidths[1] := 300;
    SGCandidate.ColWidths[2] := 400;
    SGCandidate.ColWidths[3] := 350;
end;

Function FillDictionary(PartyId : Integer) : TDictionary<String,Integer>;
var
    ProfessionDictionary : TDictionary<String, Integer>;
    TempHeadCandidate : PCandidateList;
    Count : Integer;
begin
    TempHeadCandidate := Main.CandidateList.Head;
    ProfessionDictionary := TDictionary<String, Integer>.Create();
    while TempHeadCandidate <> NIL do
    begin
        if TempHeadCandidate^.Candidate.PartyId = PartyId then
        begin
            if not ProfessionDictionary.TryGetValue(TempHeadCandidate^.Candidate.Profession, Count) then
                Count := 0;
            ProfessionDictionary.AddOrSetValue(TempHeadCandidate^.Candidate.Profession, Count + 1);
        end;
        TempHeadCandidate := TempHeadCandidate^.Next;
    end;

    FillDictionary := ProfessionDictionary;
end;

Function GetMostFrequentProfession(ProfessionDict : TDictionary<String,Integer>) : String;
var
    MaxCount, Count: Integer;
    MostFrequentProfession: string;
begin
    MaxCount := 0;
    for var Profession in ProfessionDict.Keys do
    begin
        Count := ProfessionDict[Profession];
        if Count > MaxCount then
        begin
            MaxCount := Count;
            MostFrequentProfession := Profession;
        end;
    end;
    GetMostFrequentProfession := MostFrequentProfession;
end;

Procedure FillStringGrid(SG : TStringGrid);
var
    HeadCandidateList : PCandidateList;
    HeadPartyList : PPartyList;
    I, CurrentPartyId, AmountRequest, AgeAmount: Integer;
    ProfessionDictionary : TDictionary<String, Integer>;
    MostFrequentProfession : String;
begin
    ProfessionDictionary := TDictionary<String, Integer>.Create;

    ClearStringGrid(SG);
    FillHeadersSG(SG);

    HeadPartyList := Main.PartyList.Head;

    I := 1;

    while HeadPartyList <> NIL do
    begin
        SG.Cells[0, I] := HeadPartyList^.Party.Name;
        Inc(I);
        HeadPartyList := HeadPartyList^.Next;
    end;

    SG.RowCount := I;

    for I := 1 to SG.RowCount - 1 do
    begin
        HeadCandidateList := Main.CandidateList.Head;
        AmountRequest := 0;
        AgeAmount := 0;

        while HeadCandidateList <> NIL do
        begin
            CurrentPartyId := TPartyList.GetPartyPrimaryKeyByName(Main.PartyList, SG.Cells[0, I]);

            if HeadCandidateList.Candidate.PartyId = CurrentPartyId then
            begin
                Inc(AmountRequest); // Количество заявок по партии
                AgeAmount := AgeAmount + HeadCandidateList^.Candidate.Age; // Сумма возрастов

            end;

            HeadCandidateList := HeadCandidateList^.Next;
        end;

        AgeAmount := AgeAmount div AmountRequest; // Средний возраст

        ProfessionDictionary := FillDictionary(CurrentPartyId);
        MostFrequentProfession := GetMostFrequentProfession(ProfessionDictionary);

        SG.Cells[1, I] := AmountRequest.ToString;
        SG.Cells[2, I] := AgeAmount.ToString;
        SG.Cells[3, I] := MostFrequentProfession;
    end;

end;

procedure TNewsletterFrame.FrameEnter(Sender: TObject);
begin
    FillStringGrid(SGCandidate);
end;

end.