package handlers

import (
	"net/http"
	"strings"
	"time"

	"github.com/google/uuid"
	"github.com/travelswitch/travelhub/backend/internal/models"
)

// SearchFlights handles GET /api/flights.
//
// Query parameters: origin, destination (IATA codes), date (YYYY-MM-DD),
// cabin, passengers, sort (price|duration|departure), limit, offset.
func (h *Handler) SearchFlights(w http.ResponseWriter, r *http.Request) {
	id, ok := h.identity(w, r)
	if !ok {
		return
	}

	q := r.URL.Query()
	search := models.FlightSearch{
		Origin:      strings.ToUpper(strings.TrimSpace(q.Get("origin"))),
		Destination: strings.ToUpper(strings.TrimSpace(q.Get("destination"))),
		CabinClass:  strings.TrimSpace(q.Get("cabin")),
		Passengers:  intParam(r, "passengers", 1, 1, 9),
		SortBy:      q.Get("sort"),
		Limit:       intParam(r, "limit", 25, 1, 100),
		Offset:      intParam(r, "offset", 0, 0, 100000),
	}

	if raw := strings.TrimSpace(q.Get("date")); raw != "" {
		// Parsed in the server's local zone, which is what an agent selling
		// from a desk in that zone means by "flights on the 12th".
		d, err := time.ParseInLocation("2006-01-02", raw, time.Local)
		if err != nil {
			writeError(w, http.StatusBadRequest, "date must be in YYYY-MM-DD format")
			return
		}
		search.DepartDate = &d
	}

	if search.CabinClass != "" && !validCabin(search.CabinClass) {
		writeError(w, http.StatusBadRequest,
			"cabin must be one of economy, premium_economy, business, first")
		return
	}

	flights, total, err := h.Repo.SearchFlights(r.Context(), id.Tenant.ID, search)
	if err != nil {
		h.fail(w, err, "search flights")
		return
	}

	writeJSON(w, http.StatusOK, page[models.Flight]{
		Items: flights, Total: total, Limit: search.Limit, Offset: search.Offset,
	})
}

// GetFlight handles GET /api/flights/{id}.
func (h *Handler) GetFlight(w http.ResponseWriter, r *http.Request) {
	id, ok := h.identity(w, r)
	if !ok {
		return
	}

	flightID, err := uuid.Parse(r.PathValue("id"))
	if err != nil {
		writeError(w, http.StatusBadRequest, "invalid flight id")
		return
	}

	flight, err := h.Repo.FlightByID(r.Context(), id.Tenant.ID, flightID)
	if err != nil {
		h.fail(w, err, "get flight")
		return
	}
	writeJSON(w, http.StatusOK, flight)
}

// ListAirports handles GET /api/airports.
func (h *Handler) ListAirports(w http.ResponseWriter, r *http.Request) {
	id, ok := h.identity(w, r)
	if !ok {
		return
	}

	airports, err := h.Repo.ListAirports(r.Context(), id.Tenant.ID)
	if err != nil {
		h.fail(w, err, "list airports")
		return
	}
	writeJSON(w, http.StatusOK, airports)
}

// ListAirlines handles GET /api/airlines.
func (h *Handler) ListAirlines(w http.ResponseWriter, r *http.Request) {
	id, ok := h.identity(w, r)
	if !ok {
		return
	}

	airlines, err := h.Repo.ListAirlines(r.Context(), id.Tenant.ID)
	if err != nil {
		h.fail(w, err, "list airlines")
		return
	}
	writeJSON(w, http.StatusOK, airlines)
}

func validCabin(c string) bool {
	switch c {
	case "economy", "premium_economy", "business", "first":
		return true
	}
	return false
}