import { useState, useEffect } from 'react';
import { useNavigate } from 'react-router-dom';
import { validateCharacter } from '../lib/SchemaValidator';

const STORAGE_KEY = 'homeai_characters';
const ACTIVE_KEY = 'homeai_active_character';

function loadProfiles() {
  try {
    const raw = localStorage.getItem(STORAGE_KEY);
    return raw ? JSON.parse(raw) : [];
  } catch {
    return [];
  }
}

function saveProfiles(profiles) {
  localStorage.setItem(STORAGE_KEY, JSON.stringify(profiles));
}

function getActiveId() {
  return localStorage.getItem(ACTIVE_KEY) || null;
}

function setActiveId(id) {
  localStorage.setItem(ACTIVE_KEY, id);
}

export default function Characters() {
  const [profiles, setProfiles] = useState(loadProfiles);
  const [activeId, setActive] = useState(getActiveId);
  const [error, setError] = useState(null);
  const [dragOver, setDragOver] = useState(false);
  const navigate = useNavigate();

  useEffect(() => {
    saveProfiles(profiles);
  }, [profiles]);

  const handleImport = (e) => {
    const files = Array.from(e.target?.files || []);
    importFiles(files);
    if (e.target) e.target.value = '';
  };

  const importFiles = (files) => {
    files.forEach(file => {
      if (!file.name.endsWith('.json')) return;
      const reader = new FileReader();
      reader.onload = (ev) => {
        try {
          const data = JSON.parse(ev.target.result);
          validateCharacter(data);
          const id = data.name + '_' + Date.now();
          setProfiles(prev => [...prev, { id, data, image: null, addedAt: new Date().toISOString() }]);
          setError(null);
        } catch (err) {
          setError(`Import failed for ${file.name}: ${err.message}`);
        }
      };
      reader.readAsText(file);
    });
  };

  const handleDrop = (e) => {
    e.preventDefault();
    setDragOver(false);
    const files = Array.from(e.dataTransfer.files);
    importFiles(files);
  };

  const handleImageUpload = (profileId, e) => {
    const file = e.target.files[0];
    if (!file) return;
    const reader = new FileReader();
    reader.onload = (ev) => {
      setProfiles(prev =>
        prev.map(p => p.id === profileId ? { ...p, image: ev.target.result } : p)
      );
    };
    reader.readAsDataURL(file);
  };

  const removeProfile = (id) => {
    setProfiles(prev => prev.filter(p => p.id !== id));
    if (activeId === id) {
      setActive(null);
      localStorage.removeItem(ACTIVE_KEY);
    }
  };

  const activateProfile = (id) => {
    setActive(id);
    setActiveId(id);
  };

  const exportProfile = (profile) => {
    const dataStr = "data:text/json;charset=utf-8," + encodeURIComponent(JSON.stringify(profile.data, null, 2));
    const a = document.createElement('a');
    a.href = dataStr;
    a.download = `${profile.data.name || 'character'}.json`;
    a.click();
  };

  const editProfile = (profile) => {
    sessionStorage.setItem('edit_character', JSON.stringify(profile.data));
    sessionStorage.setItem('edit_character_profile_id', profile.id);
    navigate('/editor');
  };

  const activeProfile = profiles.find(p => p.id === activeId);

  return (
    <div className="space-y-8">
      {/* Header */}
      <div className="flex items-center justify-between">
        <div>
          <h1 className="text-3xl font-bold text-gray-100">Characters</h1>
          <p className="text-sm text-gray-500 mt-1">
            {profiles.length} profile{profiles.length !== 1 ? 's' : ''} stored
            {activeProfile && (
              <span className="ml-2 text-emerald-400">
                Active: {activeProfile.data.display_name || activeProfile.data.name}
              </span>
            )}
          </p>
        </div>
        <label className="flex items-center gap-2 px-4 py-2 bg-indigo-600 hover:bg-indigo-500 text-white rounded-lg cursor-pointer transition-colors">
          <svg className="w-4 h-4" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={2}>
            <path strokeLinecap="round" strokeLinejoin="round" d="M12 4.5v15m7.5-7.5h-15" />
          </svg>
          Import JSON
          <input type="file" accept=".json" multiple className="hidden" onChange={handleImport} />
        </label>
      </div>

      {error && (
        <div className="bg-red-900/30 border border-red-500/50 text-red-300 px-4 py-3 rounded-lg text-sm">
          {error}
        </div>
      )}

      {/* Drop zone */}
      <div
        onDragOver={(e) => { e.preventDefault(); setDragOver(true); }}
        onDragLeave={() => setDragOver(false)}
        onDrop={handleDrop}
        className={`border-2 border-dashed rounded-xl p-8 text-center transition-colors ${
          dragOver
            ? 'border-indigo-500 bg-indigo-500/10'
            : 'border-gray-700 hover:border-gray-600'
        }`}
      >
        <svg className="w-10 h-10 mx-auto text-gray-600 mb-3" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={1}>
          <path strokeLinecap="round" strokeLinejoin="round" d="M3 16.5v2.25A2.25 2.25 0 005.25 21h13.5A2.25 2.25 0 0021 18.75V16.5m-13.5-9L12 3m0 0l4.5 4.5M12 3v13.5" />
        </svg>
        <p className="text-gray-500 text-sm">Drop character JSON files here to import</p>
      </div>

      {/* Profile grid */}
      {profiles.length === 0 ? (
        <div className="text-center py-16">
          <svg className="w-16 h-16 mx-auto text-gray-700 mb-4" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={1}>
            <path strokeLinecap="round" strokeLinejoin="round" d="M15.75 6a3.75 3.75 0 11-7.5 0 3.75 3.75 0 017.5 0zM4.501 20.118a7.5 7.5 0 0114.998 0A17.933 17.933 0 0112 21.75c-2.676 0-5.216-.584-7.499-1.632z" />
          </svg>
          <p className="text-gray-500">No character profiles yet. Import a JSON file to get started.</p>
        </div>
      ) : (
        <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-6">
          {profiles.map(profile => {
            const isActive = profile.id === activeId;
            const char = profile.data;
            return (
              <div
                key={profile.id}
                className={`relative rounded-xl border overflow-hidden transition-all duration-200 ${
                  isActive
                    ? 'border-emerald-500/60 bg-emerald-500/5 ring-1 ring-emerald-500/30'
                    : 'border-gray-700 bg-gray-800/50 hover:border-gray-600'
                }`}
              >
                {/* Image area */}
                <div className="relative h-48 bg-gray-900 flex items-center justify-center overflow-hidden group">
                  {profile.image ? (
                    <img
                      src={profile.image}
                      alt={char.display_name || char.name}
                      className="w-full h-full object-cover"
                    />
                  ) : (
                    <div className="text-6xl font-bold text-gray-700 select-none">
                      {(char.display_name || char.name || '?')[0].toUpperCase()}
                    </div>
                  )}
                  <label className="absolute inset-0 flex items-center justify-center bg-black/50 opacity-0 group-hover:opacity-100 transition-opacity cursor-pointer">
                    <div className="text-center">
                      <svg className="w-8 h-8 mx-auto text-white/80 mb-1" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={1.5}>
                        <path strokeLinecap="round" strokeLinejoin="round" d="M6.827 6.175A2.31 2.31 0 015.186 7.23c-.38.054-.757.112-1.134.175C2.999 7.58 2.25 8.507 2.25 9.574V18a2.25 2.25 0 002.25 2.25h15A2.25 2.25 0 0021.75 18V9.574c0-1.067-.75-1.994-1.802-2.169a47.865 47.865 0 00-1.134-.175 2.31 2.31 0 01-1.64-1.055l-.822-1.316a2.192 2.192 0 00-1.736-1.039 48.774 48.774 0 00-5.232 0 2.192 2.192 0 00-1.736 1.039l-.821 1.316z" />
                        <path strokeLinecap="round" strokeLinejoin="round" d="M16.5 12.75a4.5 4.5 0 11-9 0 4.5 4.5 0 019 0z" />
                      </svg>
                      <span className="text-xs text-white/70">Change image</span>
                    </div>
                    <input
                      type="file"
                      accept="image/*"
                      className="hidden"
                      onChange={(e) => handleImageUpload(profile.id, e)}
                    />
                  </label>
                  {isActive && (
                    <span className="absolute top-2 right-2 px-2 py-0.5 bg-emerald-500 text-white text-xs font-medium rounded-full">
                      Active
                    </span>
                  )}
                </div>

                {/* Info */}
                <div className="p-4 space-y-3">
                  <div>
                    <h3 className="text-lg font-semibold text-gray-200">
                      {char.display_name || char.name}
                    </h3>
                    <p className="text-xs text-gray-500 mt-0.5">{char.description}</p>
                  </div>

                  <div className="flex flex-wrap gap-1.5">
                    <span className="px-2 py-0.5 bg-gray-700/70 text-gray-400 text-xs rounded-full">
                      {char.tts?.engine || 'kokoro'}
                    </span>
                    <span className="px-2 py-0.5 bg-gray-700/70 text-gray-400 text-xs rounded-full">
                      {char.model_overrides?.primary || 'default'}
                    </span>
                    {char.tts?.kokoro_voice && (
                      <span className="px-2 py-0.5 bg-gray-700/70 text-gray-400 text-xs rounded-full">
                        {char.tts.kokoro_voice}
                      </span>
                    )}
                  </div>

                  <div className="flex gap-2 pt-1">
                    {!isActive ? (
                      <button
                        onClick={() => activateProfile(profile.id)}
                        className="flex-1 px-3 py-1.5 bg-emerald-600 hover:bg-emerald-500 text-white text-sm rounded-lg transition-colors"
                      >
                        Activate
                      </button>
                    ) : (
                      <button
                        disabled
                        className="flex-1 px-3 py-1.5 bg-gray-700 text-gray-500 text-sm rounded-lg cursor-not-allowed"
                      >
                        Active
                      </button>
                    )}
                    <button
                      onClick={() => editProfile(profile)}
                      className="px-3 py-1.5 bg-gray-700 hover:bg-gray-600 text-gray-300 text-sm rounded-lg transition-colors"
                      title="Edit"
                    >
                      <svg className="w-4 h-4" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={2}>
                        <path strokeLinecap="round" strokeLinejoin="round" d="M16.862 4.487l1.687-1.688a1.875 1.875 0 112.652 2.652L10.582 16.07a4.5 4.5 0 01-1.897 1.13L6 18l.8-2.685a4.5 4.5 0 011.13-1.897l8.932-8.931zm0 0L19.5 7.125M18 14v4.75A2.25 2.25 0 0115.75 21H5.25A2.25 2.25 0 013 18.75V8.25A2.25 2.25 0 015.25 6H10" />
                      </svg>
                    </button>
                    <button
                      onClick={() => exportProfile(profile)}
                      className="px-3 py-1.5 bg-gray-700 hover:bg-gray-600 text-gray-300 text-sm rounded-lg transition-colors"
                      title="Export"
                    >
                      <svg className="w-4 h-4" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={2}>
                        <path strokeLinecap="round" strokeLinejoin="round" d="M3 16.5v2.25A2.25 2.25 0 005.25 21h13.5A2.25 2.25 0 0021 18.75V16.5M16.5 12L12 16.5m0 0L7.5 12m4.5 4.5V3" />
                      </svg>
                    </button>
                    <button
                      onClick={() => removeProfile(profile.id)}
                      className="px-3 py-1.5 bg-gray-700 hover:bg-red-600 text-gray-300 hover:text-white text-sm rounded-lg transition-colors"
                      title="Delete"
                    >
                      <svg className="w-4 h-4" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={2}>
                        <path strokeLinecap="round" strokeLinejoin="round" d="M14.74 9l-.346 9m-4.788 0L9.26 9m9.968-3.21c.342.052.682.107 1.022.166m-1.022-.165L18.16 19.673a2.25 2.25 0 01-2.244 2.077H8.084a2.25 2.25 0 01-2.244-2.077L4.772 5.79m14.456 0a48.108 48.108 0 00-3.478-.397m-12 .562c.34-.059.68-.114 1.022-.165m0 0a48.11 48.11 0 013.478-.397m7.5 0v-.916c0-1.18-.91-2.164-2.09-2.201a51.964 51.964 0 00-3.32 0c-1.18.037-2.09 1.022-2.09 2.201v.916m7.5 0a48.667 48.667 0 00-7.5 0" />
                      </svg>
                    </button>
                  </div>
                </div>
              </div>
            );
          })}
        </div>
      )}
    </div>
  );
}