package handlers

import (
	"log/slog"
	"net/http"

	"qbank/internal/auth"
	"qbank/internal/db"
	"qbank/internal/models"
)

type HistoryHandler struct {
	auth   *auth.Manager
	repo   *db.Repo
	render *Renderer
}

func NewHistoryHandler(a *auth.Manager, repo *db.Repo, r *Renderer) *HistoryHandler {
	return &HistoryHandler{auth: a, repo: repo, render: r}
}

// TestHistoryItem pairs a test with its correct-answer count.
type TestHistoryItem struct {
	*models.Test
	NCorrect int
}

func (h *HistoryHandler) Handle(w http.ResponseWriter, r *http.Request) {
	user := auth.UserFromCtx(r.Context())

	tests, err := h.repo.ListTestsForUser(user.ID)
	if err != nil {
		slog.Error("list tests for history", "err", err)
		HTTPError(w, http.StatusInternalServerError)
		return
	}

	correctCounts, err := h.repo.GetCorrectCountsForUser(user.ID)
	if err != nil {
		slog.Error("get correct counts", "err", err)
		HTTPError(w, http.StatusInternalServerError)
		return
	}

	items := make([]TestHistoryItem, 0, len(tests))
	for _, t := range tests {
		if !t.CompletedAt.Valid {
			continue // skip in-progress tests
		}
		items = append(items, TestHistoryItem{
			Test:     t,
			NCorrect: correctCounts[t.ID],
		})
	}

	totalCorrect, totalAnswered, err := h.repo.GetAggregateStats(user.ID)
	if err != nil {
		slog.Error("get aggregate stats", "err", err)
		HTTPError(w, http.StatusInternalServerError)
		return
	}

	weakSpots, err := h.repo.GetWeakSpots(user.ID)
	if err != nil {
		slog.Error("get weak spots", "err", err)
		HTTPError(w, http.StatusInternalServerError)
		return
	}

	data := BaseData(h.auth, r)
	data["Items"] = items
	data["TotalCorrect"] = totalCorrect
	data["TotalAnswered"] = totalAnswered
	data["WeakSpots"] = weakSpots
	h.render.Render(w, http.StatusOK, "history", data)
}