proposal-system/api/src/ProposalSystem.Api/Controllers/AdminController.cs

using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using ProposalSystem.Application.DTOs;
using ProposalSystem.Domain.Entities;
using ProposalSystem.Infrastructure.Data;

namespace ProposalSystem.Api.Controllers;

[ApiController]
[Route("api/admin")]
[Authorize(Roles = "admins,sysadmins")]
public class AdminController : ControllerBase
{
    private readonly ProposalDbContext _db;

    public AdminController(ProposalDbContext db)
    {
        _db = db;
    }

    [HttpGet("dashboard")]
    public async Task<ActionResult<DashboardResponse>> GetDashboard(CancellationToken ct)
    {
        var pendingCount = await _db.Proposals
            .CountAsync(p => p.Status == ProposalStatus.InReview, ct);

        var weekStart = DateTime.UtcNow.AddDays(-7);
        var approvedThisWeek = await _db.Proposals
            .CountAsync(p => p.ApprovedAt >= weekStart, ct);

        var approvedTimes = await _db.Proposals
            .Where(p => p.ApprovedAt.HasValue)
            .Select(p => new { p.ApprovedAt, p.SubmittedAt })
            .ToListAsync(ct);

        var avgTurnaround = approvedTimes.Count > 0
            ? approvedTimes.Average(p => (p.ApprovedAt!.Value - p.SubmittedAt).TotalHours)
            : 0;

        var totalProposals = await _db.Proposals.CountAsync(ct);

        return Ok(new DashboardResponse(pendingCount, approvedThisWeek, avgTurnaround, totalProposals));
    }
}