package main

import (
	"encoding/csv"
	"encoding/json"
	"net/http"
	"strconv"
)

func (app *App) handleListAttendees(w http.ResponseWriter, r *http.Request) {
	q := r.URL.Query()
	attendees, err := app.listAttendees(q.Get("search"), q.Get("ticket_type"), q.Get("checked_in"))
	if err != nil {
		writeError(w, err.Error(), http.StatusInternalServerError)
		return
	}
	types, _ := app.attendeeTicketTypes()
	total, checkedIn, _ := app.attendeeCounts()
	writeJSON(w, map[string]any{
		"attendees":    attendees,
		"ticket_types": types,
		"total":        total,
		"checked_in":   checkedIn,
	})
}

func (app *App) handleCreateAttendee(w http.ResponseWriter, r *http.Request) {
	var a Attendee
	if err := json.NewDecoder(r.Body).Decode(&a); err != nil {
		writeError(w, "invalid request", http.StatusBadRequest)
		return
	}
	if a.Name == "" {
		writeError(w, "name is required", http.StatusBadRequest)
		return
	}
	created, err := app.createAttendee(a)
	if err != nil {
		writeError(w, err.Error(), http.StatusInternalServerError)
		return
	}
	w.WriteHeader(http.StatusCreated)
	writeJSON(w, created)
}

func (app *App) handleGetAttendee(w http.ResponseWriter, r *http.Request) {
	id, err := strconv.Atoi(r.PathValue("id"))
	if err != nil {
		writeError(w, "invalid id", http.StatusBadRequest)
		return
	}
	a, err := app.getAttendee(id)
	if err != nil || a == nil {
		writeError(w, "not found", http.StatusNotFound)
		return
	}
	writeJSON(w, a)
}

func (app *App) handleUpdateAttendee(w http.ResponseWriter, r *http.Request) {
	id, err := strconv.Atoi(r.PathValue("id"))
	if err != nil {
		writeError(w, "invalid id", http.StatusBadRequest)
		return
	}
	var a Attendee
	if err := json.NewDecoder(r.Body).Decode(&a); err != nil {
		writeError(w, "invalid request", http.StatusBadRequest)
		return
	}
	if a.Name == "" {
		writeError(w, "name is required", http.StatusBadRequest)
		return
	}
	a.ID = id
	if err := app.updateAttendee(a); err != nil {
		writeError(w, err.Error(), http.StatusInternalServerError)
		return
	}
	updated, _ := app.getAttendee(id)
	writeJSON(w, updated)
}

func (app *App) handleDeleteAttendee(w http.ResponseWriter, r *http.Request) {
	id, err := strconv.Atoi(r.PathValue("id"))
	if err != nil {
		writeError(w, "invalid id", http.StatusBadRequest)
		return
	}
	if err := app.deleteAttendee(id); err != nil {
		writeError(w, err.Error(), http.StatusInternalServerError)
		return
	}
	w.WriteHeader(http.StatusNoContent)
}

// handleCheckInAttendee handles POST /api/attendees/:id/checkin.
// Optional body: {"count": N, "also_volunteer": true}
// Returns {"attendee": ..., "volunteer": ...} — volunteer is included if also_volunteer=true
// and the attendee has a linked volunteer record.
func (app *App) handleCheckInAttendee(w http.ResponseWriter, r *http.Request) {
	id, err := strconv.Atoi(r.PathValue("id"))
	if err != nil {
		writeError(w, "invalid id", http.StatusBadRequest)
		return
	}

	var body struct {
		Count         int  `json:"count"`
		AlsoVolunteer bool `json:"also_volunteer"`
	}
	body.Count = 1
	json.NewDecoder(r.Body).Decode(&body)
	if body.Count < 1 {
		body.Count = 1
	}

	claims := claimsFromContext(r)
	a, err := app.checkInAttendee(id, claims.UserID, body.Count)
	if err != nil {
		writeError(w, err.Error(), http.StatusInternalServerError)
		return
	}

	result := map[string]any{"attendee": a}

	if body.AlsoVolunteer {
		v, _ := app.getVolunteerByAttendeeID(id)
		if v != nil {
			if !v.CheckedIn {
				if v2, err := app.checkInVolunteer(v.ID, claims.UserID); err == nil {
					result["volunteer"] = v2
					app.broker.publish("checkin", map[string]any{"type": "volunteer", "volunteer": v2})
				}
			} else {
				result["volunteer"] = v
			}
		}
	}

	app.broker.publish("checkin", map[string]any{"type": "attendee", "attendee": a})
	writeJSON(w, result)
}

func (app *App) handleExportAttendees(w http.ResponseWriter, r *http.Request) {
	attendees, err := app.listAttendees("", "", "")
	if err != nil {
		writeError(w, err.Error(), http.StatusInternalServerError)
		return
	}
	w.Header().Set("Content-Type", "text/csv")
	w.Header().Set("Content-Disposition", `attachment; filename="attendees.csv"`)
	wr := csv.NewWriter(w)
	wr.Write([]string{"name", "email", "phone", "ticket_id", "ticket_type", "party_size", "checked_in_count", "note", "checked_in"})
	for _, a := range attendees {
		ci := "no"
		if a.CheckedIn {
			ci = "yes"
		}
		wr.Write([]string{
			a.Name, a.Email, a.Phone, a.TicketID, a.TicketType,
			strconv.Itoa(a.PartySize), strconv.Itoa(a.CheckedInCount),
			a.Note, ci,
		})
	}
	wr.Flush()
}