using Budget.Api.Data;
using Budget.Api.DTOs;
using Budget.Api.Models;
using Budget.Api.Services;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;

namespace Budget.Api.Controllers;

[ApiController]
[Route("api/budgets/{budgetId:guid}/incomes")]
[Authorize]
public class IncomesController(AppDbContext db, BudgetAuthorizationService authz) : ControllerBase
{
    private string UserId => User.FindFirst("sub")!.Value;

    private static IncomeDto ToDto(Income i) => new(
        i.Id, i.BudgetId, i.Name, i.Frequency, i.Amount,
        FrequencyCalculator.ToMonthly(i.Amount, i.Frequency),
        FrequencyCalculator.ToAnnually(i.Amount, i.Frequency),
        i.SortOrder);

    [HttpGet]
    public async Task<IActionResult> List(Guid budgetId)
    {
        if (!await authz.CanReadAsync(budgetId, UserId)) return Forbid();
        var incomes = await db.Incomes
            .Where(i => i.BudgetId == budgetId)
            .OrderBy(i => i.SortOrder)
            .ToListAsync();
        return Ok(incomes.Select(ToDto));
    }

    [HttpPost]
    public async Task<IActionResult> Create(Guid budgetId, [FromBody] CreateIncomeRequest req)
    {
        if (!await authz.CanWriteAsync(budgetId, UserId)) return Forbid();
        var maxOrder = await db.Incomes.Where(i => i.BudgetId == budgetId).MaxAsync(i => (int?)i.SortOrder) ?? -1;
        var income = new Income
        {
            Id = Guid.NewGuid(),
            BudgetId = budgetId,
            Name = req.Name,
            Frequency = req.Frequency,
            Amount = req.Amount,
            SortOrder = maxOrder + 1,
        };
        db.Incomes.Add(income);
        await db.SaveChangesAsync();
        return Ok(ToDto(income));
    }

    [HttpPut("{incomeId:guid}")]
    public async Task<IActionResult> Update(Guid budgetId, Guid incomeId, [FromBody] UpdateIncomeRequest req)
    {
        if (!await authz.CanWriteAsync(budgetId, UserId)) return Forbid();
        var income = await db.Incomes.FirstOrDefaultAsync(i => i.Id == incomeId && i.BudgetId == budgetId);
        if (income is null) return NotFound();
        income.Name = req.Name;
        income.Frequency = req.Frequency;
        income.Amount = req.Amount;
        await db.SaveChangesAsync();
        return Ok(ToDto(income));
    }

    [HttpDelete("{incomeId:guid}")]
    public async Task<IActionResult> Delete(Guid budgetId, Guid incomeId)
    {
        if (!await authz.CanWriteAsync(budgetId, UserId)) return Forbid();
        var income = await db.Incomes.FirstOrDefaultAsync(i => i.Id == incomeId && i.BudgetId == budgetId);
        if (income is null) return NotFound();
        db.Incomes.Remove(income);
        await db.SaveChangesAsync();
        return NoContent();
    }

    [HttpPut("order")]
    public async Task<IActionResult> Reorder(Guid budgetId, [FromBody] ReorderIncomesRequest req)
    {
        if (!await authz.CanWriteAsync(budgetId, UserId)) return Forbid();
        var incomes = await db.Incomes.Where(i => i.BudgetId == budgetId).ToListAsync();
        var lookup = incomes.ToDictionary(i => i.Id);
        for (int idx = 0; idx < req.OrderedIds.Count; idx++)
        {
            if (lookup.TryGetValue(req.OrderedIds[idx], out var income))
                income.SortOrder = idx;
        }
        await db.SaveChangesAsync();
        return NoContent();
    }
}