package handlers

import (
	"fmt"
	"net/http"
	"strconv"
	"time"

	"go-crm/internal/db"
	"go-crm/internal/templates"

	"github.com/go-chi/chi/v5"
)

func (a *App) ListSchedules(w http.ResponseWriter, r *http.Request) {
	accountID, ok := a.requireAuth(w, r)
	if !ok {
		return
	}

	limit, _ := strconv.Atoi(r.URL.Query().Get("limit"))
	offset, _ := strconv.Atoi(r.URL.Query().Get("offset"))
	clientID, _ := strconv.ParseInt(r.URL.Query().Get("client_id"), 10, 64)
	customerID, _ := strconv.ParseInt(r.URL.Query().Get("customer_id"), 10, 64)
	if limit == 0 {
		limit = 20
	}

	schedules, err := db.ListSchedules(a.DB, clientID, customerID, limit, offset)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	clients, err := db.ListClients(a.DB, accountID, limit, offset)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	customers, err := db.ListCustomers(a.DB, accountID, clientID, limit, offset)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	services, err := db.ListServices(a.DB, accountID, clientID, limit, offset)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	var clientOptions, customerOptions, serviceOptions string
	clientNames := make(map[int64]string)
	customerNames := make(map[int64]string)
	serviceNames := make(map[int64]string)
	for _, c := range clients {
		clientOptions += fmt.Sprintf(`<option value="%d">%s</option>`, c.ClientID, htmlEscape(c.Name))
		clientNames[c.ClientID] = c.Name
	}
	for _, cu := range customers {
		customerOptions += fmt.Sprintf(`<option value="%d">%s</option>`, cu.CustomerID, htmlEscape(cu.Name))
		customerNames[cu.CustomerID] = cu.Name
	}
	for _, s := range services {
		serviceOptions += fmt.Sprintf(`<option value="%d">%s</option>`, s.ServiceID, htmlEscape(s.Name))
		serviceNames[s.ServiceID] = s.Name
	}

	buf := templates.BufRender()
	actions := `<button type="button" onclick="document.getElementById('scheduleForm').classList.toggle('hidden')" class="btn-primary"><svg class="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24"><path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M12 4v16m8-8H4"/></svg> Add Schedule</button>`
	fmt.Fprint(buf, templates.PageHeader("Scheduling", "Appointments and calendar", actions))

	fmt.Fprintf(buf, `
<div id="scheduleForm" class="hidden mb-6 animate-slide-up">
    <div class="card-industrial p-5">
        <h3 class="text-sm font-semibold text-zinc-200 mb-4">New Appointment</h3>
        <form hx-post="/scheduling" hx-target="#scheduleList" hx-swap="innerHTML" class="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-4">
            <select name="client_id" required class="input-industrial"><option value="">Select Client</option>%s</select>
            <select name="customer_id" required class="input-industrial"><option value="">Select Customer</option>%s</select>
            <select name="service_id" required class="input-industrial"><option value="">Select Service</option>%s</select>
            <input type="date" name="plan_date" class="input-industrial">
            <input type="time" name="time" class="input-industrial">
            <select name="status" class="input-industrial"><option value="pending">Pending</option><option value="confirmed">Confirmed</option><option value="cancelled">Cancelled</option></select>
            <div class="flex items-end"><button type="submit" class="btn-primary">Save</button></div>
        </form>
    </div>
</div>`, clientOptions, customerOptions, serviceOptions)

	if len(schedules) == 0 {
		fmt.Fprint(buf, templates.EmptyState(`<path stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M8 7V3m8 4V3m-9 8h10M5 21h14a2 2 0 002-2V7a2 2 0 00-2-2H5a2 2 0 00-2 2v12a2 2 0 002 2z"/>`, "No appointments scheduled yet."))
	} else {
		fmt.Fprintf(buf, `<div class="card-industrial overflow-hidden animate-slide-up stagger-1"><div class="overflow-x-auto">`)
		fmt.Fprint(buf, templates.TableStart([]string{"Client", "Customer", "Service", "Date", "Time", "Status", "Actions"}))
		for _, s := range schedules {
			clientName := clientNames[s.ClientID]
			if clientName == "" {
				clientName = strconv.FormatInt(s.ClientID, 10)
			}
			customerName := customerNames[s.CustomerID]
			if customerName == "" {
				customerName = strconv.FormatInt(s.CustomerID, 10)
			}
			serviceName := serviceNames[s.ServiceID]
			if serviceName == "" {
				serviceName = strconv.FormatInt(s.ServiceID, 10)
			}
			statusPill := statusPillForSchedule(s.Status)
			fmt.Fprintf(buf, `<tr>
                <td class="text-zinc-300 text-sm">%s</td>
                <td class="text-zinc-300 text-sm">%s</td>
                <td class="text-zinc-400 text-xs">%s</td>
                <td class="font-mono text-xs text-zinc-300">%s</td>
                <td class="font-mono text-xs text-zinc-300">%s</td>
                <td>%s</td>
                <td>
                    <div class="flex items-center gap-2">
                        <a href="/scheduling/%d" class="btn-ghost btn-sm">View</a>
                        <button type="button" onclick="document.getElementById('editSched%d').classList.toggle('hidden')" class="btn-ghost btn-sm">Edit</button>
                        <form hx-delete="/scheduling/%d" hx-target="closest tr" hx-swap="outerHTML" style="display:inline">
                            <button type="submit" class="btn-danger btn-sm" onclick="return confirm('Delete?')">Delete</button>
                        </form>
                    </div>
                </td>
            </tr>`, htmlEscape(clientName), htmlEscape(customerName), htmlEscape(serviceName), htmlEscape(s.PlanDate), htmlEscape(s.Time), statusPill, s.ScheduleID, s.ScheduleID, s.ScheduleID)
		}
		fmt.Fprint(buf, templates.TableEnd())
		fmt.Fprintf(buf, `</div></div>`)

		for _, s := range schedules {
			clientName := clientNames[s.ClientID]
			customerName := customerNames[s.CustomerID]
			serviceName := serviceNames[s.ServiceID]
			fmt.Fprintf(buf, `
<div id="editSched%d" class="hidden mt-4 animate-slide-up">
    <div class="card-industrial p-5 border-amber-400/10">
        <h3 class="text-sm font-semibold text-zinc-200 mb-3">Edit Appointment #%d</h3>
        <form hx-put="/scheduling/%d" hx-target="#scheduleList" hx-swap="innerHTML" class="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-3">
            <select name="client_id" class="input-industrial text-xs"><option value="%d">%s</option>%s</select>
            <select name="customer_id" class="input-industrial text-xs"><option value="%d">%s</option>%s</select>
            <select name="service_id" class="input-industrial text-xs"><option value="%d">%s</option>%s</select>
            <input type="date" name="plan_date" value="%s" class="input-industrial text-xs">
            <input type="time" name="time" value="%s" class="input-industrial text-xs">
            <select name="status" class="input-industrial text-xs"><option value="%s">%s</option><option value="pending">Pending</option><option value="confirmed">Confirmed</option><option value="cancelled">Cancelled</option></select>
            <div class="flex items-end gap-2">
                <button type="submit" class="btn-primary btn-sm">Save</button>
                <button type="button" onclick="document.getElementById('editSched%d').classList.add('hidden')" class="btn-ghost btn-sm">Cancel</button>
            </div>
        </form>
    </div>
</div>`, s.ScheduleID, s.ScheduleID, s.ScheduleID, s.ClientID, htmlEscape(clientName), clientOptions, s.CustomerID, htmlEscape(customerName), customerOptions, s.ServiceID, htmlEscape(serviceName), serviceOptions, htmlEscape(s.PlanDate), htmlEscape(s.Time), s.Status, s.Status, s.ScheduleID)
		}
	}

	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	templates.WritePage(w, buf, "Scheduling", "scheduling")
}

func statusPillForSchedule(status string) string {
	switch status {
	case "confirmed":
		return `<span class="pill pill-emerald">confirmed</span>`
	case "cancelled":
		return `<span class="pill pill-rose">cancelled</span>`
	default:
		return `<span class="pill pill-amber">pending</span>`
	}
}

func (a *App) CreateSchedule(w http.ResponseWriter, r *http.Request) {
	_, ok := a.requireAuth(w, r)
	if !ok {
		return
	}

	r.ParseForm()
	clientID, _ := strconv.ParseInt(r.FormValue("client_id"), 10, 64)
	customerID, _ := strconv.ParseInt(r.FormValue("customer_id"), 10, 64)
	serviceID, _ := strconv.ParseInt(r.FormValue("service_id"), 10, 64)
	schedule := db.Schedule{
		ClientID:   clientID,
		CustomerID: customerID,
		ServiceID:  serviceID,
		PlanDate:   r.FormValue("plan_date"),
		Time:       r.FormValue("time"),
		Status:     r.FormValue("status"),
		CreatedAt:  time.Now().Unix(),
	}

	if err := schedule.Create(a.DB); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.Header().Set("HX-Refresh", "true")
}

func (a *App) ViewSchedule(w http.ResponseWriter, r *http.Request) {
	_, ok := a.requireAuth(w, r)
	if !ok {
		return
	}

	id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
	var sch db.Schedule
	err := a.DB.QueryRow("SELECT schedule_id, client_id, customer_id, service_id, plan_date, time, status, created_at FROM scheduling WHERE schedule_id = ?", id).Scan(&sch.ScheduleID, &sch.ClientID, &sch.CustomerID, &sch.ServiceID, &sch.PlanDate, &sch.Time, &sch.Status, &sch.CreatedAt)
	if err != nil {
		http.Error(w, "Schedule not found", http.StatusNotFound)
		return
	}

	buf := templates.BufRender()
	fmt.Fprint(buf, templates.PageHeader("Appointment", "Schedule details"))
	statusPill := statusPillForSchedule(sch.Status)
	fmt.Fprintf(buf, `
<div class="max-w-lg animate-slide-up">
    <div class="card-industrial p-6">
        <div class="flex items-center gap-2 mb-6">%s</div>
        <div class="space-y-3">
            <div class="flex justify-between py-3 border-b border-white/[0.04]">
                <span class="text-xs font-mono uppercase text-zinc-500">Date</span>
                <span class="text-sm font-mono text-zinc-300">%s</span>
            </div>
            <div class="flex justify-between py-3 border-b border-white/[0.04]">
                <span class="text-xs font-mono uppercase text-zinc-500">Time</span>
                <span class="text-sm font-mono text-zinc-300">%s</span>
            </div>
            <div class="flex justify-between py-3">
                <span class="text-xs font-mono uppercase text-zinc-500">Client / Customer / Service</span>
                <span class="text-sm text-zinc-300 text-right font-mono">%d / %d / %d</span>
            </div>
        </div>
        <div class="mt-6">
            <a href="/scheduling" class="btn-ghost btn-sm">Back</a>
        </div>
    </div>
</div>`, statusPill, htmlEscape(sch.PlanDate), htmlEscape(sch.Time), sch.ClientID, sch.CustomerID, sch.ServiceID)

	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	templates.WritePage(w, buf, "Appointment", "scheduling")
}

func (a *App) UpdateSchedule(w http.ResponseWriter, r *http.Request) {
	_, ok := a.requireAuth(w, r)
	if !ok {
		return
	}

	id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
	r.ParseForm()
	clientID, _ := strconv.ParseInt(r.FormValue("client_id"), 10, 64)
	customerID, _ := strconv.ParseInt(r.FormValue("customer_id"), 10, 64)
	serviceID, _ := strconv.ParseInt(r.FormValue("service_id"), 10, 64)
	_, err := a.DB.Exec("UPDATE scheduling SET client_id=?, customer_id=?, service_id=?, plan_date=?, time=?, status=? WHERE schedule_id=?", clientID, customerID, serviceID, r.FormValue("plan_date"), r.FormValue("time"), r.FormValue("status"), id)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
	w.Header().Set("HX-Refresh", "true")
}

func (a *App) DeleteSchedule(w http.ResponseWriter, r *http.Request) {
	_, ok := a.requireAuth(w, r)
	if !ok {
		return
	}

	id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
	a.DB.Exec("DELETE FROM scheduling WHERE schedule_id = ?", id)
}

// --- package-level shims ---

func ListSchedules(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).ListSchedules(w, r)
}
func CreateSchedule(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).CreateSchedule(w, r)
}
func ViewSchedule(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).ViewSchedule(w, r)
}
func UpdateSchedule(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).UpdateSchedule(w, r)
}
func DeleteSchedule(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).DeleteSchedule(w, r)
}