"use client";

import { useEffect, useState, useCallback } from "react";
import { useRouter } from "next/navigation";
import { useAuth } from "@/lib/auth";
import { useTranslation } from "@/lib/i18n";
import {
  getProjects,
  createProject,
  deleteProject,
  Project,
} from "@/lib/api";

export default function ProjectsPage() {
  const { token, user } = useAuth();
  const { t } = useTranslation();
  const router = useRouter();
  const [projects, setProjects] = useState<Project[]>([]);
  const [loading, setLoading] = useState(true);
  const [showForm, setShowForm] = useState(false);
  const [error, setError] = useState<string | null>(null);

  // Form state
  const [formName, setFormName] = useState("");
  const [formDesc, setFormDesc] = useState("");
  const [formColor, setFormColor] = useState("#3B82F6");
  const [formIcon, setFormIcon] = useState("\ud83d\udcc1");

  const COLORS = ["#3B82F6", "#EF4444", "#10B981", "#F59E0B", "#8B5CF6", "#EC4899", "#6366F1", "#14B8A6"];
  const ICONS = ["\ud83d\udcc1", "\ud83d\ude80", "\ud83d\udca1", "\ud83c\udfaf", "\ud83d\udee0\ufe0f", "\ud83c\udf1f", "\ud83d\udcca", "\ud83d\udd25"];

  const loadData = useCallback(async () => {
    if (!token) return;
    setLoading(true);
    try {
      const res = await getProjects(token);
      setProjects(res.data || []);
    } catch (err) {
      console.error("Load error:", err);
      setError(t("common.error"));
    } finally {
      setLoading(false);
    }
  }, [token, t]);

  useEffect(() => {
    if (!token) {
      router.replace("/login");
      return;
    }
    loadData();
  }, [token, router, loadData]);

  async function handleCreate(e: React.FormEvent) {
    e.preventDefault();
    if (!token || !formName.trim()) return;
    try {
      await createProject(token, {
        name: formName.trim(),
        description: formDesc,
        color: formColor,
        icon: formIcon,
        owner_id: user?.id,
      });
      setFormName("");
      setFormDesc("");
      setFormColor("#3B82F6");
      setFormIcon("\ud83d\udcc1");
      setShowForm(false);
      loadData();
    } catch (err) {
      console.error("Create error:", err);
      setError(t("common.error"));
    }
  }

  async function handleDelete(id: string) {
    if (!token) return;
    if (!confirm(t("tasks.confirmDelete"))) return;
    try {
      await deleteProject(token, id);
      loadData();
    } catch (err) {
      console.error("Delete error:", err);
      setError(t("common.error"));
    }
  }

  function formatDate(d: string) {
    return new Date(d).toLocaleDateString("cs-CZ", { day: "numeric", month: "short" });
  }

  if (!token) return null;

  return (
    <div className="space-y-4 pb-24 sm:pb-8 px-4 sm:px-0">
      {/* Header */}
      <div className="flex items-center justify-between">
        <h1 className="text-xl font-bold dark:text-white">{t("nav.projects")}</h1>
        <button
          onClick={() => setShowForm(!showForm)}
          className="px-4 py-2 bg-blue-600 hover:bg-blue-700 text-white rounded-lg text-sm font-medium transition-colors min-h-[44px]"
        >
          {showForm ? t("tasks.form.cancel") : `+ ${t("projects.add")}`}
        </button>
      </div>

      {/* Error */}
      {error && (
        <div className="bg-red-50 dark:bg-red-900/20 border border-red-200 dark:border-red-800 rounded-lg p-3 text-red-700 dark:text-red-300 text-sm">
          {error}
          <button onClick={() => setError(null)} className="ml-2 underline">{t("tasks.close")}</button>
        </div>
      )}

      {/* Create form */}
      {showForm && (
        <form onSubmit={handleCreate} className="bg-white dark:bg-gray-900 rounded-xl border border-gray-200 dark:border-gray-800 p-4 space-y-3">
          <div>
            <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">{t("tasks.form.title")}</label>
            <input
              type="text"
              value={formName}
              onChange={(e) => setFormName(e.target.value)}
              placeholder={t("projects.namePlaceholder")}
              className="w-full px-3 py-2 border rounded-lg dark:bg-gray-800 dark:border-gray-700 dark:text-white focus:ring-2 focus:ring-blue-500 focus:border-blue-500 min-h-[44px]"
              required
            />
          </div>
          <div>
            <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">{t("tasks.form.description")}</label>
            <textarea
              value={formDesc}
              onChange={(e) => setFormDesc(e.target.value)}
              placeholder={t("projects.descPlaceholder")}
              className="w-full px-3 py-2 border rounded-lg dark:bg-gray-800 dark:border-gray-700 dark:text-white focus:ring-2 focus:ring-blue-500 min-h-[80px] resize-none"
              rows={2}
            />
          </div>
          <div className="grid grid-cols-2 gap-3">
            <div>
              <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">{t("projects.color")}</label>
              <div className="flex gap-1.5 flex-wrap">
                {COLORS.map((c) => (
                  <button
                    key={c}
                    type="button"
                    onClick={() => setFormColor(c)}
                    className={`w-8 h-8 rounded-full border-2 transition-all ${formColor === c ? "border-gray-900 dark:border-white scale-110" : "border-transparent"}`}
                    style={{ backgroundColor: c }}
                  />
                ))}
              </div>
            </div>
            <div>
              <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">{t("projects.icon")}</label>
              <div className="flex gap-1.5 flex-wrap">
                {ICONS.map((ic) => (
                  <button
                    key={ic}
                    type="button"
                    onClick={() => setFormIcon(ic)}
                    className={`w-8 h-8 rounded-lg flex items-center justify-center text-lg border-2 transition-all ${formIcon === ic ? "border-blue-500 bg-blue-50 dark:bg-blue-900/20" : "border-gray-200 dark:border-gray-700"}`}
                  >
                    {ic}
                  </button>
                ))}
              </div>
            </div>
          </div>
          <button
            type="submit"
            className="w-full py-2.5 bg-blue-600 hover:bg-blue-700 text-white rounded-lg font-medium transition-colors min-h-[44px]"
          >
            {t("projects.add")}
          </button>
        </form>
      )}

      {/* Projects list */}
      {loading ? (
        <div className="flex justify-center py-12">
          <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-blue-600" />
        </div>
      ) : projects.length === 0 ? (
        <div className="text-center py-16">
          <div className="text-5xl mb-4 opacity-50">{"\ud83d\udcc2"}</div>
          <p className="text-gray-500 dark:text-gray-400 text-lg font-medium">{t("projects.empty")}</p>
          <p className="text-gray-400 dark:text-gray-500 text-sm mt-1">{t("projects.createFirst")}</p>
        </div>
      ) : (
        <div className="space-y-2">
          {projects.map((project) => (
            <div
              key={project.id}
              className="bg-white dark:bg-gray-900 rounded-xl border border-gray-200 dark:border-gray-800 p-4 transition-all hover:shadow-md"
            >
              <div className="flex items-start justify-between gap-3">
                <div className="flex items-start gap-3 flex-1 min-w-0">
                  <div
                    className="w-10 h-10 rounded-lg flex items-center justify-center text-xl flex-shrink-0"
                    style={{ backgroundColor: (project.color || "#3B82F6") + "15" }}
                  >
                    {project.icon || "\ud83d\udcc1"}
                  </div>
                  <div className="flex-1 min-w-0">
                    <h3 className="font-semibold text-gray-900 dark:text-white truncate">{project.name}</h3>
                    {project.description && (
                      <p className="text-sm text-gray-500 dark:text-gray-400 truncate mt-0.5">{project.description}</p>
                    )}
                    <div className="flex items-center gap-3 mt-1.5 text-xs text-gray-400 dark:text-gray-500">
                      <span>{t("projects.tasks")}: {project.task_count || 0}</span>
                      <span>{t("projects.members")}: {project.members?.length || 0}</span>
                      <span>{formatDate(project.created_at)}</span>
                    </div>
                  </div>
                </div>
                <div className="flex items-center gap-1 flex-shrink-0">
                  <div className="w-3 h-3 rounded-full" style={{ backgroundColor: project.color || "#3B82F6" }} />
                  <button
                    onClick={() => handleDelete(project.id)}
                    className="p-2 text-gray-400 hover:text-red-500 transition-colors min-h-[44px] min-w-[44px] flex items-center justify-center"
                    title={t("tasks.delete")}
                  >
                    <svg className="w-4 h-4" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={2}>
                      <path strokeLinecap="round" strokeLinejoin="round" d="M19 7l-.867 12.142A2 2 0 0116.138 21H7.862a2 2 0 01-1.995-1.858L5 7m5 4v6m4-6v6m1-10V4a1 1 0 00-1-1h-4a1 1 0 00-1 1v3M4 7h16" />
                    </svg>
                  </button>
                </div>
              </div>
            </div>
          ))}
        </div>
      )}
    </div>
  );
}