'use client';

import { useState } from 'react';
import { Plus, Edit, Trash2, X, Check, AlertCircle, Zap } from 'lucide-react';
import { createPlan, updatePlan, deletePlan, grantMonthlyCredits, type SubscriptionPlan } from '@/services/subscription-service';

interface PlanManagementClientProps {
    initialPlans: SubscriptionPlan[];
}

export default function PlanManagementClient({ initialPlans }: PlanManagementClientProps) {
    const [plans, setPlans] = useState<SubscriptionPlan[]>(initialPlans);
    const [editingPlan, setEditingPlan] = useState<SubscriptionPlan | null>(null);
    const [isCreating, setIsCreating] = useState(false);
    const [formData, setFormData] = useState({
        name: '',
        display_name: '',
        monthly_credits: 0,
        price: 0,
        description: '',
        is_active: true,
        sort_order: 0
    });
    const [loading, setLoading] = useState(false);
    const [message, setMessage] = useState<{ type: 'success' | 'error'; text: string } | null>(null);

    const handleEdit = (plan: SubscriptionPlan) => {
        setEditingPlan(plan);
        setFormData({
            name: plan.name,
            display_name: plan.display_name,
            monthly_credits: plan.monthly_credits,
            price: plan.price,
            description: plan.description || '',
            is_active: plan.is_active,
            sort_order: plan.sort_order
        });
        setIsCreating(false);
        setMessage(null);
    };

    const handleCreate = () => {
        setEditingPlan(null);
        setFormData({
            name: '',
            display_name: '',
            monthly_credits: 0,
            price: 0,
            description: '',
            is_active: true,
            sort_order: plans.length + 1
        });
        setIsCreating(true);
        setMessage(null);
    };

    const handleSave = async () => {
        if (!formData.name || !formData.display_name || formData.monthly_credits <= 0) {
            setMessage({ type: 'error', text: 'Please fill in all required fields' });
            return;
        }

        setLoading(true);
        setMessage(null);

        if (isCreating) {
            const result = await createPlan(formData);
            if (result.success && result.plan) {
                setPlans([...plans, result.plan]);
                setMessage({ type: 'success', text: 'Plan created successfully' });
                setIsCreating(false);
            } else {
                setMessage({ type: 'error', text: result.error || 'Failed to create plan' });
            }
        } else if (editingPlan) {
            const result = await updatePlan(editingPlan.id, formData);
            if (result.success) {
                setPlans(plans.map(p => p.id === editingPlan.id ? { ...p, ...formData } : p));
                setMessage({ type: 'success', text: 'Plan updated successfully' });
                setEditingPlan(null);
            } else {
                setMessage({ type: 'error', text: result.error || 'Failed to update plan' });
            }
        }

        setLoading(false);
    };

    const handleDelete = async (planId: string) => {
        if (!confirm('Are you sure you want to delete this plan? Users on this plan will be unassigned.')) {
            return;
        }

        setLoading(true);
        const result = await deletePlan(planId);

        if (result.success) {
            setPlans(plans.filter(p => p.id !== planId));
            setMessage({ type: 'success', text: 'Plan deleted successfully' });
        } else {
            setMessage({ type: 'error', text: result.error || 'Failed to delete plan' });
        }

        setLoading(false);
    };

    const handleGrantCredits = async () => {
        if (!confirm('Grant monthly credits to all users based on their subscription plan?')) {
            return;
        }

        setLoading(true);
        setMessage(null);

        const result = await grantMonthlyCredits();

        if (result.success) {
            setMessage({
                type: 'success',
                text: `Credits granted! Processed: ${result.processed}, Failed: ${result.failed}`
            });
        } else {
            setMessage({ type: 'error', text: result.error || 'Failed to grant credits' });
        }

        setLoading(false);
    };

    return (
        <div className="space-y-6">
            {/* Actions Bar */}
            <div className="bg-white dark:bg-zinc-900 rounded-2xl p-6 border border-zinc-200 dark:border-zinc-800 shadow-sm">
                <div className="flex gap-3">
                    <button
                        onClick={handleCreate}
                        className="flex-1 py-3 bg-amber-600 hover:bg-amber-700 text-white font-bold rounded-xl transition-colors flex items-center justify-center gap-2"
                    >
                        <Plus size={18} />
                        Create New Plan
                    </button>
                    <button
                        onClick={handleGrantCredits}
                        disabled={loading}
                        className="flex-1 py-3 bg-green-600 hover:bg-green-700 text-white font-bold rounded-xl transition-colors flex items-center justify-center gap-2 disabled:opacity-50"
                    >
                        <Zap size={18} />
                        Grant Monthly Credits
                    </button>
                </div>
            </div>

            {message && (
                <div className={`p-4 rounded-xl flex items-center gap-3 ${message.type === 'success'
                        ? 'bg-green-100 dark:bg-green-900/30 text-green-700 dark:text-green-500'
                        : 'bg-red-100 dark:bg-red-900/30 text-red-700 dark:text-red-500'
                    }`}>
                    {message.type === 'success' ? <Check size={20} /> : <AlertCircle size={20} />}
                    {message.text}
                </div>
            )}

            {/* Plans Grid */}
            <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-4 gap-6">
                {plans.map((plan) => (
                    <div
                        key={plan.id}
                        className={`bg-white dark:bg-zinc-900 rounded-2xl p-6 border-2 ${plan.is_active
                                ? 'border-amber-200 dark:border-amber-800'
                                : 'border-zinc-200 dark:border-zinc-800 opacity-60'
                            } shadow-sm relative`}
                    >
                        {!plan.is_active && (
                            <div className="absolute top-4 right-4 px-2 py-1 bg-zinc-200 dark:bg-zinc-700 text-zinc-600 dark:text-zinc-400 text-xs font-bold rounded">
                                Inactive
                            </div>
                        )}
                        <div className="mb-4">
                            <h3 className="text-2xl font-black text-zinc-900 dark:text-white">{plan.display_name}</h3>
                            <p className="text-xs text-zinc-500 mt-1">{plan.name}</p>
                        </div>
                        <div className="mb-4">
                            <div className="text-3xl font-black text-amber-600">{plan.monthly_credits}</div>
                            <div className="text-xs text-zinc-500">Credits/Month</div>
                        </div>
                        <div className="mb-4">
                            <div className="text-2xl font-bold text-zinc-900 dark:text-white">€{plan.price.toFixed(2)}</div>
                            <div className="text-xs text-zinc-500">per month</div>
                        </div>
                        {plan.description && (
                            <p className="text-sm text-zinc-600 dark:text-zinc-400 mb-4">{plan.description}</p>
                        )}
                        <div className="flex gap-2">
                            <button
                                onClick={() => handleEdit(plan)}
                                className="flex-1 py-2 bg-zinc-900 dark:bg-zinc-100 text-white dark:text-zinc-900 font-bold rounded-lg text-sm transition-colors flex items-center justify-center gap-2"
                            >
                                <Edit size={14} />
                                Edit
                            </button>
                            <button
                                onClick={() => handleDelete(plan.id)}
                                className="px-3 py-2 bg-red-600 hover:bg-red-700 text-white font-bold rounded-lg text-sm transition-colors"
                            >
                                <Trash2 size={14} />
                            </button>
                        </div>
                    </div>
                ))}
            </div>

            {/* Edit/Create Modal */}
            {(editingPlan || isCreating) && (
                <div className="fixed inset-0 bg-black/50 flex items-center justify-center p-4 z-50">
                    <div className="bg-white dark:bg-zinc-900 rounded-2xl p-6 max-w-2xl w-full border border-zinc-200 dark:border-zinc-800">
                        <div className="flex items-center justify-between mb-6">
                            <h3 className="text-2xl font-black text-zinc-900 dark:text-white">
                                {isCreating ? 'Create Plan' : 'Edit Plan'}
                            </h3>
                            <button
                                onClick={() => { setEditingPlan(null); setIsCreating(false); }}
                                className="p-2 hover:bg-zinc-100 dark:hover:bg-zinc-800 rounded-lg transition-colors"
                            >
                                <X size={20} />
                            </button>
                        </div>

                        <div className="space-y-4">
                            <div className="grid grid-cols-2 gap-4">
                                <div>
                                    <label className="block text-xs font-bold text-zinc-400 uppercase mb-2">Name (ID)</label>
                                    <input
                                        type="text"
                                        value={formData.name}
                                        onChange={(e) => setFormData({ ...formData, name: e.target.value })}
                                        placeholder="e.g. starter"
                                        className="w-full px-4 py-2 bg-zinc-50 dark:bg-zinc-800 border border-zinc-200 dark:border-zinc-700 rounded-xl text-sm focus:outline-none focus:ring-2 focus:ring-amber-500/50"
                                    />
                                </div>
                                <div>
                                    <label className="block text-xs font-bold text-zinc-400 uppercase mb-2">Display Name</label>
                                    <input
                                        type="text"
                                        value={formData.display_name}
                                        onChange={(e) => setFormData({ ...formData, display_name: e.target.value })}
                                        placeholder="e.g. Starter"
                                        className="w-full px-4 py-2 bg-zinc-50 dark:bg-zinc-800 border border-zinc-200 dark:border-zinc-700 rounded-xl text-sm focus:outline-none focus:ring-2 focus:ring-amber-500/50"
                                    />
                                </div>
                            </div>

                            <div className="grid grid-cols-2 gap-4">
                                <div>
                                    <label className="block text-xs font-bold text-zinc-400 uppercase mb-2">Monthly Credits</label>
                                    <input
                                        type="number"
                                        value={formData.monthly_credits}
                                        onChange={(e) => setFormData({ ...formData, monthly_credits: parseInt(e.target.value) || 0 })}
                                        className="w-full px-4 py-2 bg-zinc-50 dark:bg-zinc-800 border border-zinc-200 dark:border-zinc-700 rounded-xl text-sm focus:outline-none focus:ring-2 focus:ring-amber-500/50"
                                    />
                                </div>
                                <div>
                                    <label className="block text-xs font-bold text-zinc-400 uppercase mb-2">Price (€)</label>
                                    <input
                                        type="number"
                                        step="0.01"
                                        value={formData.price}
                                        onChange={(e) => setFormData({ ...formData, price: parseFloat(e.target.value) || 0 })}
                                        className="w-full px-4 py-2 bg-zinc-50 dark:bg-zinc-800 border border-zinc-200 dark:border-zinc-700 rounded-xl text-sm focus:outline-none focus:ring-2 focus:ring-amber-500/50"
                                    />
                                </div>
                            </div>

                            <div>
                                <label className="block text-xs font-bold text-zinc-400 uppercase mb-2">Description</label>
                                <textarea
                                    value={formData.description}
                                    onChange={(e) => setFormData({ ...formData, description: e.target.value })}
                                    placeholder="Brief description of the plan"
                                    rows={3}
                                    className="w-full px-4 py-2 bg-zinc-50 dark:bg-zinc-800 border border-zinc-200 dark:border-zinc-700 rounded-xl text-sm focus:outline-none focus:ring-2 focus:ring-amber-500/50"
                                />
                            </div>

                            <div className="grid grid-cols-2 gap-4">
                                <div>
                                    <label className="block text-xs font-bold text-zinc-400 uppercase mb-2">Sort Order</label>
                                    <input
                                        type="number"
                                        value={formData.sort_order}
                                        onChange={(e) => setFormData({ ...formData, sort_order: parseInt(e.target.value) || 0 })}
                                        className="w-full px-4 py-2 bg-zinc-50 dark:bg-zinc-800 border border-zinc-200 dark:border-zinc-700 rounded-xl text-sm focus:outline-none focus:ring-2 focus:ring-amber-500/50"
                                    />
                                </div>
                                <div className="flex items-end">
                                    <label className="flex items-center gap-2 cursor-pointer">
                                        <input
                                            type="checkbox"
                                            checked={formData.is_active}
                                            onChange={(e) => setFormData({ ...formData, is_active: e.target.checked })}
                                            className="w-5 h-5 rounded border-zinc-300 text-amber-600 focus:ring-amber-500"
                                        />
                                        <span className="text-sm font-bold text-zinc-900 dark:text-white">Active</span>
                                    </label>
                                </div>
                            </div>

                            <button
                                onClick={handleSave}
                                disabled={loading}
                                className="w-full py-3 bg-amber-600 hover:bg-amber-700 text-white font-bold rounded-xl transition-colors disabled:opacity-50 flex items-center justify-center gap-2"
                            >
                                <Check size={18} />
                                {isCreating ? 'Create Plan' : 'Save Changes'}
                            </button>
                        </div>
                    </div>
                </div>
            )}
        </div>
    );
}