import { useState } from 'react';
import { Trash2, RefreshCw, GitBranch, Loader2, ServerCrash, ChevronRight } from 'lucide-react';
import { usePlugins } from '../../contexts/PluginsContext';
import PluginIcon from './PluginIcon';
import type { Plugin } from '../../contexts/PluginsContext';

/* ─── Toggle Switch ─────────────────────────────────────────────────────── */
function ToggleSwitch({ checked, onChange }: { checked: boolean; onChange: (v: boolean) => void }) {
  return (
    <label className="relative inline-flex items-center cursor-pointer select-none">
      <input
        type="checkbox"
        className="sr-only peer"
        checked={checked}
        onChange={(e) => onChange(e.target.checked)}
      />
      <div
        className={`
          relative w-9 h-5 rounded-full transition-colors duration-200
          bg-muted peer-checked:bg-emerald-500
          after:absolute after:content-[''] after:top-[2px] after:left-[2px]
          after:w-4 after:h-4 after:rounded-full after:bg-white after:shadow-sm
          after:transition-transform after:duration-200
          peer-checked:after:translate-x-4
        `}
      />
    </label>
  );
}

/* ─── Server Dot ────────────────────────────────────────────────────────── */
function ServerDot({ running }: { running: boolean }) {
  if (!running) return null;
  return (
    <span className="relative flex items-center gap-1.5">
      <span className="relative flex h-1.5 w-1.5">
        <span className="animate-ping absolute inline-flex h-full w-full rounded-full bg-emerald-400 opacity-75" />
        <span className="relative inline-flex rounded-full h-1.5 w-1.5 bg-emerald-500" />
      </span>
      <span className="text-[10px] font-mono text-emerald-600 dark:text-emerald-400 tracking-wide uppercase">
        running
      </span>
    </span>
  );
}

/* ─── Plugin Card ───────────────────────────────────────────────────────── */
type PluginCardProps = {
  plugin: Plugin;
  index: number;
  onToggle: (enabled: boolean) => void;
  onUpdate: () => void;
  onUninstall: () => void;
  updating: boolean;
  confirmingUninstall: boolean;
  onCancelUninstall: () => void;
  updateError: string | null;
};

function PluginCard({
  plugin,
  index,
  onToggle,
  onUpdate,
  onUninstall,
  updating,
  confirmingUninstall,
  onCancelUninstall,
  updateError,
}: PluginCardProps) {
  const accentColor = plugin.enabled
    ? 'bg-emerald-500'
    : 'bg-muted-foreground/20';

  return (
    <div
      className="relative flex rounded-md border border-border bg-card overflow-hidden transition-opacity duration-200"
      style={{
        opacity: plugin.enabled ? 1 : 0.65,
        animationDelay: `${index * 40}ms`,
      }}
    >
      {/* Left accent bar */}
      <div className={`w-[3px] flex-shrink-0 ${accentColor} transition-colors duration-300`} />

      <div className="flex-1 p-3.5 min-w-0">
        {/* Header row */}
        <div className="flex items-start justify-between gap-3">
          <div className="flex items-center gap-2.5 min-w-0">
            <div className="flex-shrink-0 w-4 h-4 text-foreground/80">
              <PluginIcon
                pluginName={plugin.name}
                iconFile={plugin.icon}
                className="w-4 h-4 [&>svg]:w-full [&>svg]:h-full"
              />
            </div>
            <div className="min-w-0">
              <div className="flex items-center gap-2 flex-wrap">
                <span className="font-semibold text-sm text-foreground leading-none">
                  {plugin.displayName}
                </span>
                <span className="font-mono text-[10px] text-muted-foreground bg-muted px-1.5 py-0.5 rounded">
                  v{plugin.version}
                </span>
                <span className="font-mono text-[10px] text-muted-foreground bg-muted px-1.5 py-0.5 rounded">
                  {plugin.type}
                </span>
                <ServerDot running={!!plugin.serverRunning} />
              </div>
              {plugin.description && (
                <p className="text-xs text-muted-foreground mt-1 leading-snug">
                  {plugin.description}
                </p>
              )}
              {plugin.author && (
                <p className="text-[10px] font-mono text-muted-foreground/60 mt-0.5">
                  {plugin.author}
                </p>
              )}
            </div>
          </div>

          {/* Controls */}
          <div className="flex items-center gap-2 flex-shrink-0">
            <button
              onClick={onUpdate}
              disabled={updating}
              title="Pull latest from git"
              className="p-1.5 rounded text-muted-foreground hover:text-foreground hover:bg-muted transition-colors disabled:opacity-40"
            >
              {updating ? (
                <Loader2 className="w-3.5 h-3.5 animate-spin" />
              ) : (
                <RefreshCw className="w-3.5 h-3.5" />
              )}
            </button>

            <button
              onClick={onUninstall}
              title={confirmingUninstall ? 'Click again to confirm' : 'Uninstall plugin'}
              className={`p-1.5 rounded transition-colors ${
                confirmingUninstall
                  ? 'text-red-500 bg-red-50 dark:bg-red-900/20 hover:bg-red-100 dark:hover:bg-red-900/30'
                  : 'text-muted-foreground hover:text-red-500 hover:bg-muted'
              }`}
            >
              <Trash2 className="w-3.5 h-3.5" />
            </button>

            <ToggleSwitch checked={plugin.enabled} onChange={onToggle} />
          </div>
        </div>

        {/* Confirm uninstall banner */}
        {confirmingUninstall && (
          <div className="mt-3 flex items-center justify-between gap-3 px-3 py-2 rounded bg-red-50 dark:bg-red-950/30 border border-red-200 dark:border-red-800/50">
            <span className="text-xs text-red-600 dark:text-red-400">
              Remove <span className="font-semibold">{plugin.displayName}</span>? This cannot be undone.
            </span>
            <div className="flex gap-1.5">
              <button
                onClick={onCancelUninstall}
                className="text-xs px-2.5 py-1 rounded border border-border text-muted-foreground hover:text-foreground hover:bg-muted transition-colors"
              >
                Cancel
              </button>
              <button
                onClick={onUninstall}
                className="text-xs px-2.5 py-1 rounded border border-red-300 dark:border-red-700 text-red-600 dark:text-red-400 hover:bg-red-100 dark:hover:bg-red-900/30 font-medium transition-colors"
              >
                Remove
              </button>
            </div>
          </div>
        )}

        {/* Update error */}
        {updateError && (
          <div className="mt-2 flex items-center gap-1.5 text-xs text-red-500">
            <ServerCrash className="w-3 h-3 flex-shrink-0" />
            <span>{updateError}</span>
          </div>
        )}
      </div>
    </div>
  );
}

/* ─── Empty State ───────────────────────────────────────────────────────── */
function EmptyState() {
  return (
    <div className="flex flex-col items-center justify-center py-12 text-center">
      <div className="font-mono text-muted-foreground/30 text-xs leading-relaxed mb-4 select-none">
        <div>~/.claude-code-ui/plugins/</div>
        <div className="flex items-center justify-center gap-1 mt-1">
          <ChevronRight className="w-3 h-3" />
          <span>(empty)</span>
        </div>
      </div>
      <p className="text-sm text-muted-foreground">No plugins installed</p>
      <p className="text-xs text-muted-foreground/60 mt-1">
        Install from git or drop a folder in the plugins directory
      </p>
    </div>
  );
}

/* ─── Main Component ────────────────────────────────────────────────────── */
export default function PluginSettingsTab() {
  const { plugins, loading, installPlugin, uninstallPlugin, updatePlugin, togglePlugin } =
    usePlugins();

  const [gitUrl, setGitUrl] = useState('');
  const [installing, setInstalling] = useState(false);
  const [installError, setInstallError] = useState<string | null>(null);
  const [confirmUninstall, setConfirmUninstall] = useState<string | null>(null);
  const [updatingPlugin, setUpdatingPlugin] = useState<string | null>(null);
  const [updateErrors, setUpdateErrors] = useState<Record<string, string>>({});

  const handleUpdate = async (name: string) => {
    setUpdatingPlugin(name);
    setUpdateErrors((prev) => { const next = { ...prev }; delete next[name]; return next; });
    const result = await updatePlugin(name);
    if (!result.success) {
      setUpdateErrors((prev) => ({ ...prev, [name]: result.error || 'Update failed' }));
    }
    setUpdatingPlugin(null);
  };

  const handleInstall = async () => {
    if (!gitUrl.trim()) return;
    setInstalling(true);
    setInstallError(null);
    const result = await installPlugin(gitUrl.trim());
    if (result.success) {
      setGitUrl('');
    } else {
      setInstallError(result.error || 'Installation failed');
    }
    setInstalling(false);
  };

  const handleUninstall = async (name: string) => {
    if (confirmUninstall !== name) {
      setConfirmUninstall(name);
      return;
    }
    await uninstallPlugin(name);
    setConfirmUninstall(null);
  };

  return (
    <div className="space-y-5">
      {/* Header */}
      <div className="flex items-baseline justify-between">
        <div>
          <h3 className="text-sm font-semibold uppercase tracking-widest text-muted-foreground/60 mb-1">
            Plugins
          </h3>
          <p className="text-xs text-muted-foreground">
            Extend the interface with custom tabs. Drop a folder in{' '}
            <code className="font-mono text-[10px] bg-muted px-1.5 py-0.5 rounded">
              ~/.claude-code-ui/plugins/
            </code>{' '}
            or install from git.
          </p>
        </div>
        {!loading && plugins.length > 0 && (
          <span className="font-mono text-xs text-muted-foreground/50 tabular-nums">
            {plugins.filter((p) => p.enabled).length}/{plugins.length}
          </span>
        )}
      </div>

      {/* Install from Git */}
      <div className="rounded-md border border-border bg-card p-3.5">
        <div className="flex items-center gap-2 mb-3">
          <GitBranch className="w-3.5 h-3.5 text-muted-foreground/60" />
          <span className="text-xs font-mono text-muted-foreground uppercase tracking-widest">
            Install from git
          </span>
        </div>

        <div className="flex items-center gap-0 rounded-md border border-border bg-background focus-within:ring-1 focus-within:ring-ring overflow-hidden">
          <span className="flex-shrink-0 pl-3 pr-1.5 font-mono text-xs text-muted-foreground/50 select-none">
            $
          </span>
          <input
            type="text"
            value={gitUrl}
            onChange={(e) => {
              setGitUrl(e.target.value);
              setInstallError(null);
            }}
            placeholder="git clone https://github.com/user/my-plugin"
            className="flex-1 px-1.5 py-2.5 text-xs font-mono bg-transparent text-foreground placeholder:text-muted-foreground/40 focus:outline-none"
            onKeyDown={(e) => {
              if (e.key === 'Enter') void handleInstall();
            }}
          />
          <button
            onClick={handleInstall}
            disabled={installing || !gitUrl.trim()}
            className="flex-shrink-0 px-4 py-2.5 text-xs font-medium bg-foreground text-background hover:opacity-90 disabled:opacity-30 transition-opacity border-l border-border"
          >
            {installing ? (
              <Loader2 className="w-3.5 h-3.5 animate-spin" />
            ) : (
              'Install'
            )}
          </button>
        </div>

        {installError && (
          <p className="mt-2 text-xs font-mono text-red-500">{installError}</p>
        )}
      </div>

      {/* Plugin List */}
      <div className="space-y-2">
        {loading ? (
          <div className="flex items-center gap-2 justify-center py-10 text-xs text-muted-foreground font-mono">
            <Loader2 className="w-3.5 h-3.5 animate-spin" />
            scanning plugins…
          </div>
        ) : plugins.length === 0 ? (
          <EmptyState />
        ) : (
          plugins.map((plugin, index) => (
            <PluginCard
              key={plugin.name}
              plugin={plugin}
              index={index}
              onToggle={(enabled) => void togglePlugin(plugin.name, enabled)}
              onUpdate={() => void handleUpdate(plugin.name)}
              onUninstall={() => void handleUninstall(plugin.name)}
              updating={updatingPlugin === plugin.name}
              confirmingUninstall={confirmUninstall === plugin.name}
              onCancelUninstall={() => setConfirmUninstall(null)}
              updateError={updateErrors[plugin.name] ?? null}
            />
          ))
        )}
      </div>
    </div>
  );
}