CIA/e-voting-system/backend/routes/votes.py

"""
Routes pour le vote et les bulletins.
"""

from fastapi import APIRouter, HTTPException, status, Depends, Request
from sqlalchemy.orm import Session
import base64
from .. import schemas, services
from ..dependencies import get_db, get_current_voter
from ..models import Voter
from ..crypto.hashing import SecureHash

router = APIRouter(prefix="/api/votes", tags=["votes"])


@router.post("/submit", response_model=schemas.VoteResponse)
async def submit_vote(
    vote_bulletin: schemas.VoteBulletin,
    current_voter: Voter = Depends(get_current_voter),
    db: Session = Depends(get_db),
    request: Request = None
):
    """
    Soumettre un vote chiffré.
    
    Le vote doit être:
    - Chiffré avec ElGamal
    - Accompagné d'une preuve ZK de validité
    """
    
    # Vérifier que l'électeur n'a pas déjà voté
    if services.VoteService.has_voter_voted(
        db,
        current_voter.id,
        vote_bulletin.election_id
    ):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Voter has already voted in this election"
        )
    
    # Vérifier que l'élection existe
    election = services.ElectionService.get_election(
        db,
        vote_bulletin.election_id
    )
    if not election:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Election not found"
        )
    
    # Vérifier que le candidat existe
    from ..models import Candidate
    candidate = db.query(Candidate).filter(
        Candidate.id == vote_bulletin.candidate_id,
        Candidate.election_id == vote_bulletin.election_id
    ).first()
    if not candidate:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Candidate not found"
        )
    
    # Décoder le vote chiffré
    try:
        encrypted_vote_bytes = base64.b64decode(vote_bulletin.encrypted_vote)
    except Exception:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Invalid encrypted vote format"
        )
    
    # Générer le hash du bulletin
    import time
    ballot_hash = SecureHash.hash_bulletin(
        vote_id=current_voter.id,
        candidate_id=vote_bulletin.candidate_id,
        timestamp=int(time.time())
    )
    
    # Enregistrer le vote
    vote = services.VoteService.record_vote(
        db=db,
        voter_id=current_voter.id,
        election_id=vote_bulletin.election_id,
        candidate_id=vote_bulletin.candidate_id,
        encrypted_vote=encrypted_vote_bytes,
        ballot_hash=ballot_hash,
        ip_address=request.client.host if request else None
    )
    
    # Marquer l'électeur comme ayant voté
    services.VoterService.mark_as_voted(db, current_voter.id)
    
    return schemas.VoteResponse(
        id=vote.id,
        ballot_hash=ballot_hash,
        timestamp=vote.timestamp
    )


@router.get("/status")
def get_vote_status(
    election_id: int,
    current_voter: Voter = Depends(get_current_voter),
    db: Session = Depends(get_db)
):
    """Vérifier si l'électeur a déjà voté pour une élection"""
    
    has_voted = services.VoteService.has_voter_voted(
        db,
        current_voter.id,
        election_id
    )
    
    return {"has_voted": has_voted}


@router.get("/history", response_model=list)
def get_voter_history(
    current_voter: Voter = Depends(get_current_voter),
    db: Session = Depends(get_db)
):
    """Récupérer l'historique des votes de l'électeur actuel"""
    from .. import models
    from datetime import datetime
    
    votes = db.query(models.Vote).filter(
        models.Vote.voter_id == current_voter.id
    ).all()
    
    # Retourner la structure avec infos des élections
    history = []
    for vote in votes:
        election = db.query(models.Election).filter(
            models.Election.id == vote.election_id
        ).first()
        candidate = db.query(models.Candidate).filter(
            models.Candidate.id == vote.candidate_id
        ).first()
        
        if election:
            history.append({
                "vote_id": vote.id,
                "election_id": election.id,
                "election_name": election.name,
                "candidate_name": candidate.name if candidate else "Unknown",
                "vote_date": vote.timestamp,
                "election_status": "completed" if election.end_date < datetime.utcnow() else "active"
            })
    
    return history