package api

import (
	"errors"
	"net/http"

	"github.com/jackc/pgx/v5"

	"git.fabledsword.com/bvandeusen/minstrel/internal/apierror"
	"git.fabledsword.com/bvandeusen/minstrel/internal/db/dbq"
)

// systemPlaylistsStatusResp is the wire shape for the home page's placeholder
// state lookup. Fields are nullable to distinguish "no row exists yet" (all
// nulls) from "row exists with these values".
type systemPlaylistsStatusResp struct {
	InFlight  bool    `json:"in_flight"`
	LastRunAt *string `json:"last_run_at"`
	LastError *string `json:"last_error"`
}

// handleGetSystemPlaylistsStatus implements GET /api/me/system-playlists-status.
// Returns the caller's system_playlist_runs row, or zero-values when no row
// exists yet (i.e. the user has never had a build attempted).
func (h *handlers) handleGetSystemPlaylistsStatus(w http.ResponseWriter, r *http.Request) {
	caller, ok := requireUser(w, r)
	if !ok {
		return
	}

	row, err := dbq.New(h.pool).GetSystemPlaylistRun(r.Context(), caller.ID)
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			writeJSON(w, http.StatusOK, systemPlaylistsStatusResp{})
			return
		}
		h.logger.Error("api: get system playlists status", "err", err)
		writeErr(w, apierror.InternalMsg("lookup failed", err))
		return
	}

	resp := systemPlaylistsStatusResp{InFlight: row.InFlight}
	if row.LastRunAt.Valid {
		s := row.LastRunAt.Time.Format("2006-01-02T15:04:05Z07:00")
		resp.LastRunAt = &s
	}
	if row.LastError != nil {
		resp.LastError = row.LastError
	}
	writeJSON(w, http.StatusOK, resp)
}