using System.Reflection;
using JobTrackerApi.Data;
using JobTrackerApi.Services;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;

namespace JobTrackerApi.Controllers;

[ApiController]
[Route("api/admin/system")]
[Authorize(Roles = "Admin")]
public sealed class AdminSystemController : ControllerBase
{
    private readonly IConfiguration _cfg;
    private readonly AppPaths _paths;
    private readonly JobTrackerContext _db;
    private readonly ISummarizerService _summarizer;
    private readonly IWebHostEnvironment _env;

    public AdminSystemController(IConfiguration cfg, AppPaths paths, JobTrackerContext db, ISummarizerService summarizer, IWebHostEnvironment env)
    {
        _cfg = cfg;
        _paths = paths;
        _db = db;
        _summarizer = summarizer;
        _env = env;
    }

    public sealed record StorageStatusDto(string DataRoot, string DbPath, bool DbExists, long? DbSizeBytes, int CompanyCount, int JobCount, int DeletedCount);
    public sealed record EmailStatusDto(bool Enabled, string? Host, int Port, bool EnableSsl, string? From, string? FromName);
    public sealed record SystemStatusDto(
        string Environment,
        string ContentRoot,
        string Version,
        string? CommitSha,
        string? BuildStamp,
        StorageStatusDto Storage,
        EmailStatusDto Email,
        SummarizerMetrics Summarizer
    );

    [HttpGet]
    public async Task<ActionResult<SystemStatusDto>> Get(CancellationToken cancellationToken)
    {
        var dbPath = _paths.GetDbPath();
        var dbFile = new FileInfo(dbPath);

        var jobs = await _db.JobApplications.AsNoTracking().ToListAsync(cancellationToken);
        var companies = await _db.Companies.AsNoTracking().CountAsync(cancellationToken);
        var summarizer = await _summarizer.GetMetricsAsync(cancellationToken);

        var version = (_cfg["App:Version"] ?? "").Trim();
        if (string.IsNullOrWhiteSpace(version))
        {
            version = Assembly.GetExecutingAssembly().GetName().Version?.ToString() ?? "unknown";
        }
        var commitSha = (_cfg["App:CommitSha"] ?? "").Trim();
        var buildStamp = (_cfg["App:BuildStamp"] ?? "").Trim();

        return Ok(new SystemStatusDto(
            Environment: _env.EnvironmentName,
            ContentRoot: _env.ContentRootPath,
            Version: version,
            CommitSha: string.IsNullOrWhiteSpace(commitSha) ? null : commitSha,
            BuildStamp: string.IsNullOrWhiteSpace(buildStamp) ? null : buildStamp,
            Storage: new StorageStatusDto(
                DataRoot: _paths.DataRoot,
                DbPath: dbPath,
                DbExists: dbFile.Exists,
                DbSizeBytes: dbFile.Exists ? dbFile.Length : null,
                CompanyCount: companies,
                JobCount: jobs.Count,
                DeletedCount: jobs.Count(x => x.IsDeleted)
            ),
            Email: new EmailStatusDto(
                Enabled: _cfg.GetValue("Email:Enabled", false),
                Host: (_cfg["Email:SmtpHost"] ?? "").Trim(),
                Port: _cfg.GetValue("Email:SmtpPort", 587),
                EnableSsl: _cfg.GetValue("Email:SmtpEnableSsl", true),
                From: (_cfg["Email:From"] ?? "").Trim(),
                FromName: (_cfg["Email:FromName"] ?? "").Trim()
            ),
            Summarizer: summarizer
        ));
    }
}