package handlers

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

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

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

func (a *App) ListCustomers(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)
	if limit == 0 {
		limit = 20
	}

	customers, err := db.ListCustomers(a.DB, accountID, clientID, 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
	}

	var clientOptions string
	for _, c := range clients {
		clientOptions += fmt.Sprintf(`<option value="%d">%s</option>`, c.ClientID, htmlEscape(c.Name))
	}

	buf := templates.BufRender()
	actions := `<button type="button" onclick="document.getElementById('customerForm').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 Customer</button>`
	fmt.Fprint(buf, templates.PageHeader("Customers", "Your customer database", actions))

	fmt.Fprintf(buf, `
<div id="customerForm" 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 Customer</h3>
        <form hx-post="/customers" hx-target="#customerList" hx-swap="innerHTML" class="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-4">
            <input type="text" name="name" placeholder="Name" required class="input-industrial">
            <input type="tel" name="phone" placeholder="Phone" class="input-industrial">
            <input type="date" name="birth_date" class="input-industrial">
            <input type="text" name="instagram" placeholder="Instagram" class="input-industrial">
            <select name="client_id" required class="input-industrial"><option value="">Select Client</option>%s</select>
            <div class="flex items-end"><button type="submit" class="btn-primary">Save</button></div>
        </form>
    </div>
</div>`, clientOptions)

	if len(customers) == 0 {
		fmt.Fprint(buf, templates.EmptyState(`<path stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M12 4.354a4 4 0 110 5.292M15 21H3v-1a6 6 0 0112 0v1zm0 0h6v-1a6 6 0 00-9-5.197M13 7a4 4 0 11-8 0 4 4 0 018 0z"/>`, "No customers found. Add your first customer."))
	} 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{"Name", "Phone", "Birth Date", "Instagram", "Actions"}))
		for _, c := range customers {
			fmt.Fprintf(buf, `<tr>
                <td class="font-medium text-zinc-200">%s</td>
                <td class="font-mono text-xs text-zinc-300">%s</td>
                <td class="text-xs text-zinc-400">%s</td>
                <td class="text-xs text-zinc-400">%s</td>
                <td>
                    <div class="flex items-center gap-2">
                        <a href="/customers/%d" class="btn-ghost btn-sm">View</a>
                        <button type="button" onclick="document.getElementById('editCust%d').classList.toggle('hidden')" class="btn-ghost btn-sm">Edit</button>
                        <form hx-delete="/customers/%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(c.Name), htmlEscape(c.Phone), htmlEscape(c.BirthDate), htmlEscape(c.Instagram), c.CustomerID, c.CustomerID, c.CustomerID)
		}
		fmt.Fprint(buf, templates.TableEnd())
		fmt.Fprintf(buf, `</div></div>`)

		for _, c := range customers {
			fmt.Fprintf(buf, `
<div id="editCust%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 %s</h3>
        <form hx-put="/customers/%d" hx-target="#customerList" hx-swap="innerHTML" class="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-3">
            <input type="text" name="name" value="%s" class="input-industrial text-xs">
            <input type="tel" name="phone" value="%s" class="input-industrial text-xs">
            <input type="date" name="birth_date" value="%s" class="input-industrial text-xs">
            <input type="text" name="instagram" value="%s" class="input-industrial text-xs">
            <select name="client_id" class="input-industrial text-xs"><option value="%d">%s</option>%s</select>
            <div class="flex items-end gap-2">
                <button type="submit" class="btn-primary btn-sm">Save</button>
                <button type="button" onclick="document.getElementById('editCust%d').classList.add('hidden')" class="btn-ghost btn-sm">Cancel</button>
            </div>
        </form>
    </div>
</div>`, c.CustomerID, htmlEscape(c.Name), c.CustomerID, htmlEscape(c.Name), htmlEscape(c.Phone), htmlEscape(c.BirthDate), htmlEscape(c.Instagram), c.ClientID, htmlEscape(c.Name), clientOptions, c.CustomerID)
		}
	}

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

func (a *App) CreateCustomer(w http.ResponseWriter, r *http.Request) {
	isInternal := r.Header.Get("X-Internal-Secret") == config.InternalSecret()

	var accountID int64
	var clientID int64
	var ok bool

	if isInternal {
		clientID, _ = strconv.ParseInt(r.FormValue("client_id"), 10, 64)
		accountID = clientID
		ok = true
	} else {
		accountID, ok = a.requireAuth(w, r)
		if ok {
			clientID, _ = strconv.ParseInt(r.FormValue("client_id"), 10, 64)
		}
	}

	if !ok {
		return
	}

	r.ParseForm()
	if clientID == 0 {
		clientID, _ = strconv.ParseInt(r.FormValue("client_id"), 10, 64)
	}

	if !isInternal {
		var checkID int64
		err := a.DB.QueryRow("SELECT client_id FROM clients WHERE client_id = ? AND account_id = ?", clientID, accountID).Scan(&checkID)
		if err != nil {
			http.Error(w, "Invalid client", http.StatusBadRequest)
			return
		}
	}

	customer := db.Customer{
		ClientID:  clientID,
		Name:      r.FormValue("name"),
		Phone:     r.FormValue("phone"),
		BirthDate: r.FormValue("birth_date"),
		Instagram: r.FormValue("instagram"),
		CreatedAt: time.Now().Unix(),
	}

	if phone := r.FormValue("phone"); phone != "" {
		var existingID int64
		err := a.DB.QueryRow(
			"SELECT customer_id FROM customers WHERE client_id = ? AND phone = ?",
			clientID, phone,
		).Scan(&existingID)
		if err == nil {
			_, err = a.DB.Exec(
				"UPDATE customers SET name = ?, birth_date = ?, instagram = ? WHERE customer_id = ?",
				r.FormValue("name"), r.FormValue("birth_date"), r.FormValue("instagram"), existingID,
			)
			if err == nil {
				w.Header().Set("HX-Refresh", "true")
				return
			}
		}
	}

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

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

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

	id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
	var c db.Customer
	err := a.DB.QueryRow("SELECT customer_id, client_id, name, phone, birth_date, instagram, created_at FROM customers WHERE customer_id = ?", id).Scan(&c.CustomerID, &c.ClientID, &c.Name, &c.Phone, &c.BirthDate, &c.Instagram, &c.CreatedAt)
	if err != nil {
		http.Error(w, "Customer not found", http.StatusNotFound)
		return
	}

	buf := templates.BufRender()
	fmt.Fprint(buf, templates.PageHeader(htmlEscape(c.Name), "Customer profile"))
	fmt.Fprintf(buf, `
<div class="max-w-lg animate-slide-up">
    <div class="card-industrial p-6">
        <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">Phone</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">Birth Date</span>
                <span class="text-sm text-zinc-300">%s</span>
            </div>
            <div class="flex justify-between py-3">
                <span class="text-xs font-mono uppercase text-zinc-500">Instagram</span>
                <span class="text-sm text-zinc-300">%s</span>
            </div>
        </div>
        <div class="mt-6">
            <a href="/customers" class="btn-ghost btn-sm">Back</a>
        </div>
    </div>
</div>`, htmlEscape(c.Phone), htmlEscape(c.BirthDate), htmlEscape(c.Instagram))

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

func (a *App) UpdateCustomer(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)
	_, err := a.DB.Exec("UPDATE customers SET client_id=?, name=?, phone=?, birth_date=?, instagram=? WHERE customer_id=?", clientID, r.FormValue("name"), r.FormValue("phone"), r.FormValue("birth_date"), r.FormValue("instagram"), id)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}
	w.Header().Set("HX-Refresh", "true")
}

func (a *App) DeleteCustomer(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 customers WHERE customer_id = ?", id)
}

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

func ListCustomers(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).ListCustomers(w, r)
}
func CreateCustomer(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).CreateCustomer(w, r)
}
func ViewCustomer(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).ViewCustomer(w, r)
}
func UpdateCustomer(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).UpdateCustomer(w, r)
}
func DeleteCustomer(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).DeleteCustomer(w, r)
}