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) ListClients(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"))
	if limit == 0 {
		limit = 20
	}

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

	buf := templates.BufRender()
	actions := `<button type="button" onclick="document.getElementById('clientForm').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 Client</button>`
	fmt.Fprint(buf, templates.PageHeader("Clients", "Manage your business clients", actions))

	// Add form
	fmt.Fprintf(buf, `
<div id="clientForm" 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 Client</h3>
        <form hx-post="/clients" hx-target="#clientList" hx-swap="innerHTML" class="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 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="email" name="email" placeholder="Email" class="input-industrial">
            <input type="text" name="address" placeholder="Address" class="input-industrial">
            <textarea name="notes" placeholder="Notes" class="input-industrial sm:col-span-2 lg:col-span-2" rows="2"></textarea>
            <div class="flex items-end">
                <button type="submit" class="btn-primary">Save Client</button>
            </div>
        </form>
    </div>
</div>`)

	if len(clients) == 0 {
		fmt.Fprint(buf, templates.EmptyState(`<path stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M19 21V5a2 2 0 00-2-2H7a2 2 0 00-2 2v16m14 0h2m-2 0h-5m-9 0H3m2 0h5M9 7h1m-1 4h1m4-4h1m-1 4h1m-5 10v-5a1 1 0 011-1h2a1 1 0 011 1v5"/>`, "No clients found. Add your first client to get started."))
	} 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", "WhatsApp", "Created", "Actions"}))
		for _, c := range clients {
			var whatsappCell string
			if c.WhatsAppNumber == "" {
				whatsappCell = fmt.Sprintf(`<a href="/leads/connect?client_id=%d" class="btn-ghost btn-sm">Connect</a>`, c.ClientID)
			} else {
				connected := false
				if a.WAConnector != nil {
					connected, _ = a.WAConnector.IsConnected(r.Context(), c.ClientID)
				}
				if connected {
					whatsappCell = fmt.Sprintf(`<span class="flex items-center gap-1.5"><span class="w-1.5 h-1.5 rounded-full bg-emerald-400"></span><span class="font-mono text-xs text-zinc-300">%s</span></span>`, htmlEscape(c.WhatsAppNumber))
				} else if c.WhatsAppConnected == 1 {
					whatsappCell = fmt.Sprintf(`<span class="flex items-center gap-1.5"><span class="w-1.5 h-1.5 rounded-full bg-rose-400"></span><span class="font-mono text-xs text-zinc-300">%s</span><a href="/leads/connect?client_id=%d" class="text-[10px] text-amber-400 hover:underline">reconnect</a></span>`, htmlEscape(c.WhatsAppNumber), c.ClientID)
				} else {
					whatsappCell = fmt.Sprintf(`<a href="/leads/connect?client_id=%d" class="btn-ghost btn-sm">Connect</a>`, c.ClientID)
				}
			}
			created := time.Unix(c.CreatedAt, 0).Format("02/01/2006")
			fmt.Fprintf(buf, `<tr>
                <td class="font-medium text-zinc-200">%s</td>
                <td class="font-mono text-xs">%s</td>
                <td>%s</td>
                <td class="text-xs text-zinc-500">%s</td>
                <td>
                    <div class="flex items-center gap-2">
                        <a href="/clients/%d" class="btn-ghost btn-sm">View</a>
                        <button type="button" onclick="document.getElementById('editForm%d').classList.toggle('hidden')" class="btn-ghost btn-sm">Edit</button>
                        <form hx-delete="/clients/%d" hx-target="closest tr" hx-swap="outerHTML" style="display:inline">
                            <button type="submit" class="btn-danger btn-sm" onclick="return confirm('Delete this client?')">Delete</button>
                        </form>
                    </div>
                </td>
            </tr>`, htmlEscape(c.Name), htmlEscape(c.Phone), whatsappCell, created, c.ClientID, c.ClientID, c.ClientID)
		}
		fmt.Fprint(buf, templates.TableEnd())
		fmt.Fprintf(buf, `</div></div>`)

		// Edit forms (rendered below table, toggled via JS)
		for _, c := range clients {
			fmt.Fprintf(buf, `
<div id="editForm%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-4">Edit %s</h3>
        <form hx-put="/clients/%d" hx-target="#clientList" hx-swap="innerHTML" class="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 gap-4">
            <input type="text" name="name" value="%s" class="input-industrial">
            <input type="tel" name="phone" value="%s" class="input-industrial">
            <input type="email" name="email" value="%s" class="input-industrial">
            <input type="text" name="address" value="%s" class="input-industrial">
            <textarea name="notes" class="input-industrial sm:col-span-2 lg:col-span-2" rows="2">%s</textarea>
            <div class="flex items-end gap-2">
                <button type="submit" class="btn-primary">Save</button>
                <button type="button" onclick="document.getElementById('editForm%d').classList.add('hidden')" class="btn-ghost">Cancel</button>
            </div>
        </form>
    </div>
</div>`, c.ClientID, htmlEscape(c.Name), c.ClientID, htmlEscape(c.Name), htmlEscape(c.Phone), htmlEscape(c.Email), htmlEscape(c.Address), htmlEscape(c.Notes), c.ClientID)
		}
	}

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

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

	r.ParseForm()
	client := db.Client{
		AccountID: accountID,
		Name:      r.FormValue("name"),
		Phone:     r.FormValue("phone"),
		Email:     r.FormValue("email"),
		Address:   r.FormValue("address"),
		Notes:     r.FormValue("notes"),
		CreatedAt: time.Now().Unix(),
	}

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

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

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

	id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
	client, err := db.GetClientByID(a.DB, accountID, id)
	if err != nil {
		http.Error(w, "Client not found", http.StatusNotFound)
		return
	}

	buf := templates.BufRender()
	fmt.Fprint(buf, templates.PageHeader(htmlEscape(client.Name), "Client details and WhatsApp connection"))

	waSection := ""
	if client.WhatsAppNumber != "" {
		connected := false
		if a.WAConnector != nil {
			connected, _ = a.WAConnector.IsConnected(r.Context(), client.ClientID)
		}
		statusPill := `<span class="pill pill-rose">Disconnected</span>`
		if connected {
			statusPill = `<span class="pill pill-emerald">Connected</span>`
		} else if client.WhatsAppConnected == 1 {
			statusPill = `<span class="pill pill-amber">Stale</span>`
		}
		waSection = fmt.Sprintf(`
<div class="card-industrial p-5 mb-6">
    <div class="flex items-center justify-between mb-4">
        <h3 class="text-sm font-semibold text-zinc-200">WhatsApp</h3>
        %s
    </div>
    <div class="font-mono text-sm text-zinc-300">%s</div>
    <div class="mt-4">
        <a href="/leads/connect?client_id=%d" class="btn-ghost btn-sm">%s</a>
    </div>
</div>`, statusPill, htmlEscape(client.WhatsAppNumber), client.ClientID, map[bool]string{true: "Reconnect", false: "Reconnect"}[true])
	} else {
		waSection = fmt.Sprintf(`
<div class="card-industrial p-5 mb-6">
    <h3 class="text-sm font-semibold text-zinc-200 mb-2">WhatsApp</h3>
    <p class="text-sm text-zinc-500 mb-4">No WhatsApp number configured for this client.</p>
    <a href="/leads/connect?client_id=%d" class="btn-primary btn-sm">Connect WhatsApp</a>
</div>`, client.ClientID)
	}

	fmt.Fprintf(buf, `
<div class="grid grid-cols-1 lg:grid-cols-3 gap-6 animate-slide-up">
    <div class="lg:col-span-2">
        <div class="card-industrial p-5">
            <h3 class="text-sm font-semibold text-zinc-200 mb-4">Details</h3>
            <div class="space-y-3">
                <div class="flex justify-between py-2 border-b border-white/[0.04]">
                    <span class="text-xs text-zinc-500 font-mono uppercase">Phone</span>
                    <span class="text-sm text-zinc-300 font-mono">%s</span>
                </div>
                <div class="flex justify-between py-2 border-b border-white/[0.04]">
                    <span class="text-xs text-zinc-500 font-mono uppercase">Email</span>
                    <span class="text-sm text-zinc-300">%s</span>
                </div>
                <div class="flex justify-between py-2 border-b border-white/[0.04]">
                    <span class="text-xs text-zinc-500 font-mono uppercase">Address</span>
                    <span class="text-sm text-zinc-300">%s</span>
                </div>
                <div class="flex justify-between py-2">
                    <span class="text-xs text-zinc-500 font-mono uppercase">Notes</span>
                    <span class="text-sm text-zinc-300">%s</span>
                </div>
            </div>
        </div>
    </div>
    <div>
        %s
    </div>
</div>
<div class="mt-4">
    <a href="/clients" class="btn-ghost btn-sm">Back to Clients</a>
</div>`, htmlEscape(client.Phone), htmlEscape(client.Email), htmlEscape(client.Address), htmlEscape(client.Notes), waSection)

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

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

	id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
	r.ParseForm()
	client := db.Client{
		ClientID:  id,
		AccountID: accountID,
		Name:      r.FormValue("name"),
		Phone:     r.FormValue("phone"),
		Email:     r.FormValue("email"),
		Address:   r.FormValue("address"),
		Notes:     r.FormValue("notes"),
	}

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

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

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

	id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
	client := &db.Client{ClientID: id, AccountID: accountID}
	if err := client.Delete(a.DB); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	w.Write([]byte(""))
}

// --- package-level shims kept for existing tests ---

func ListClients(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).ListClients(w, r)
}
func CreateClient(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).CreateClient(w, r)
}
func ViewClient(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).ViewClient(w, r)
}
func UpdateClient(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).UpdateClient(w, r)
}
func DeleteClient(w http.ResponseWriter, r *http.Request) {
	(&App{DB: DB, WAConnector: WAConnector}).DeleteClient(w, r)
}