import React, { useEffect, useRef, useState } from 'react';
import { createRoot } from 'react-dom/client';

// ─── Safe chrome storage wrapper ─────────────────────────────────────────────

function safeStorageGet(
  storage: chrome.storage.StorageArea,
  keys: string[],
  callback: (result: Record<string, string>) => void,
) {
  try {
    if (typeof chrome === 'undefined' || !chrome.runtime?.id) return;
    storage.get(keys, callback);
  } catch (err) {
    console.warn('LexAI: Extension context invalidated', err);
  }
}

function safeStorageSet(storage: chrome.storage.StorageArea, data: Record<string, string>) {
  try {
    if (typeof chrome === 'undefined' || !chrome.runtime?.id) return;
    storage.set(data);
  } catch (err) {
    console.warn('LexAI: Extension context invalidated', err);
  }
}

async function safeSendMessage(
  message: Record<string, unknown>,
): Promise<Record<string, string> | null> {
  try {
    if (typeof chrome === 'undefined' || !chrome.runtime?.id) return null;
    return await chrome.runtime.sendMessage(message);
  } catch (err) {
    console.warn('LexAI: sendMessage failed', err);
    return null;
  }
}

// ─── Types ───────────────────────────────────────────────────────────────────

type Action = 'fix' | 'rephrase' | 'shorten' | 'expand';

// ─── Styles ──────────────────────────────────────────────────────────────────

const S = {
  root: {
    fontFamily: 'system-ui, -apple-system, sans-serif',
    background: '#1e1e2e',
    color: '#cdd6f4',
    padding: '0',
    minWidth: '420px',
    maxHeight: '600px',
    overflowY: 'auto' as const,
  },
  header: {
    display: 'flex',
    alignItems: 'center',
    justifyContent: 'space-between',
    padding: '12px 16px',
    borderBottom: '1px solid rgba(205,214,244,0.1)',
  },
  headerLeft: {
    display: 'flex',
    alignItems: 'center',
    gap: '6px',
    fontSize: '16px',
    fontWeight: 700,
  },
  settingsBtn: {
    background: 'none',
    border: '1px solid rgba(205,214,244,0.2)',
    borderRadius: '6px',
    color: '#a6adc8',
    cursor: 'pointer',
    fontSize: '12px',
    padding: '4px 10px',
  },
  section: {
    padding: '14px 16px',
  },
  divider: {
    borderTop: '1px solid rgba(205,214,244,0.1)',
  },
  textarea: {
    width: '100%',
    minHeight: '100px',
    background: 'rgba(49,50,68,0.95)',
    border: '1px solid rgba(205,214,244,0.15)',
    borderRadius: '8px',
    color: '#cdd6f4',
    fontSize: '13px',
    lineHeight: '1.5',
    padding: '10px 12px',
    resize: 'vertical' as const,
    outline: 'none',
    boxSizing: 'border-box' as const,
    fontFamily: 'inherit',
  },
  actionsRow: {
    display: 'flex',
    flexWrap: 'wrap' as const,
    gap: '8px',
    marginTop: '10px',
  },
  actionBtn: {
    background: 'linear-gradient(135deg, #cba6f7, #89b4fa)',
    border: 'none',
    borderRadius: '6px',
    color: '#1e1e2e',
    cursor: 'pointer',
    fontSize: '12px',
    fontWeight: 600,
    padding: '6px 12px',
  },
  actionBtnDisabled: {
    background: 'rgba(203,166,247,0.3)',
    border: 'none',
    borderRadius: '6px',
    color: '#a6adc8',
    cursor: 'not-allowed',
    fontSize: '12px',
    fontWeight: 600,
    padding: '6px 12px',
  },
  processingBadge: {
    fontSize: '12px',
    color: '#a6adc8',
    marginTop: '8px',
  },
  resultSection: {
    padding: '0 16px 14px',
  },
  resultLabel: {
    fontSize: '12px',
    color: '#a6adc8',
    marginBottom: '6px',
    fontWeight: 600,
  },
  resultBox: {
    background: 'rgba(49,50,68,0.8)',
    border: '1px solid rgba(205,214,244,0.1)',
    borderRadius: '8px',
    color: '#cdd6f4',
    fontSize: '13px',
    lineHeight: '1.5',
    padding: '10px 12px',
    whiteSpace: 'pre-wrap' as const,
    wordBreak: 'break-word' as const,
  },
  copyBtn: {
    marginTop: '8px',
    background: 'rgba(137,180,250,0.15)',
    border: '1px solid rgba(137,180,250,0.3)',
    borderRadius: '6px',
    color: '#89b4fa',
    cursor: 'pointer',
    fontSize: '12px',
    fontWeight: 600,
    padding: '6px 14px',
  },
  warningBox: {
    background: 'rgba(243,139,168,0.1)',
    border: '1px solid rgba(243,139,168,0.3)',
    borderRadius: '8px',
    color: '#f38ba8',
    fontSize: '12px',
    padding: '10px 12px',
    marginBottom: '12px',
  },
  errorBox: {
    background: 'rgba(243,139,168,0.1)',
    border: '1px solid rgba(243,139,168,0.3)',
    borderRadius: '8px',
    color: '#f38ba8',
    fontSize: '12px',
    padding: '10px 12px',
    marginTop: '8px',
  },
};

// ─── Component ────────────────────────────────────────────────────────────────

function Popup() {
  const [configured, setConfigured] = useState(false);
  const [provider, setProvider] = useState('');
  const [model, setModel] = useState('');
  const [inputText, setInputText] = useState('');
  const [result, setResult] = useState('');
  const [error, setError] = useState('');
  const [processing, setProcessing] = useState(false);
  const [copied, setCopied] = useState(false);
  const sessionRestored = useRef(false);

  // Load config + restore session input
  useEffect(() => {
    safeStorageGet(chrome.storage.local, ['provider', 'apiKey', 'model'], (result) => {
      if (result.apiKey) {
        setConfigured(true);
        setProvider(result.provider || 'openai');
        setModel(result.model || '');
      }
    });

    if (!sessionRestored.current) {
      sessionRestored.current = true;
      safeStorageGet(chrome.storage.session, ['lexai_popup_input'], (res) => {
        if (res.lexai_popup_input) {
          setInputText(res.lexai_popup_input);
        }
      });
    }
  }, []);

  // Persist input to session storage on change
  const handleInputChange = (e: React.ChangeEvent<HTMLTextAreaElement>) => {
    const val = e.target.value;
    setInputText(val);
    safeStorageSet(chrome.storage.session, { lexai_popup_input: val });
  };

  const openSettings = () => {
    try {
      if (typeof chrome !== 'undefined' && chrome.runtime?.id) {
        chrome.runtime.openOptionsPage();
      }
    } catch (err) {
      console.warn('LexAI: Extension context invalidated', err);
    }
  };

  const runAction = async (action: Action) => {
    const text = inputText.trim();
    if (!text || processing) return;

    setProcessing(true);
    setResult('');
    setError('');

    const response = await safeSendMessage({
      type: 'lexai-action',
      action,
      text,
    });

    setProcessing(false);

    if (!response) {
      setError('No response from extension. Try reloading.');
      return;
    }
    if (response.error) {
      setError(response.error);
      return;
    }
    if (response.result) {
      setResult(response.result);
    }
  };

  const copyResult = async () => {
    if (!result) return;
    try {
      await navigator.clipboard.writeText(result);
      setCopied(true);
      setTimeout(() => setCopied(false), 1500);
    } catch {
      // fallback
    }
  };

  const actions: { label: string; id: Action }[] = [
    { label: 'Fix Grammar', id: 'fix' },
    { label: 'Rephrase', id: 'rephrase' },
    { label: 'Shorten', id: 'shorten' },
    { label: 'Expand', id: 'expand' },
  ];

  return (
    <div style={S.root}>
      {/* Header */}
      <div style={S.header}>
        <div style={S.headerLeft}>
          <span>⚡</span>
          <span>LexAI</span>
        </div>
        <button style={S.settingsBtn} onClick={openSettings}>
          ⚙ Settings
        </button>
      </div>

      {/* Not configured warning */}
      {!configured && (
        <div style={S.section}>
          <div style={S.warningBox}>
            <strong>⚠ Setup Required</strong>
            <br />
            Add your API key in Settings to use LexAI.
          </div>
          <button
            onClick={openSettings}
            style={{
              ...S.actionBtn,
              width: '100%',
              fontSize: '13px',
              padding: '8px',
            }}
          >
            ⚙ Open Settings
          </button>
        </div>
      )}

      {/* Main input area — only when configured */}
      {configured && (
        <>
          <div style={S.section}>
            {/* Provider badge */}
            <div style={{ fontSize: '11px', color: '#a6adc8', marginBottom: '8px' }}>
              ✓ {provider}
              {model ? ` / ${model}` : ''}
            </div>

            {/* Textarea */}
            <textarea
              style={S.textarea}
              placeholder="Paste your text here..."
              value={inputText}
              onChange={handleInputChange}
              disabled={processing}
              rows={4}
            />

            {/* Action buttons */}
            <div style={S.actionsRow}>
              {actions.map(({ label, id }) => (
                <button
                  key={id}
                  style={processing ? S.actionBtnDisabled : S.actionBtn}
                  disabled={processing || !inputText.trim()}
                  onClick={() => runAction(id)}
                >
                  {label}
                </button>
              ))}
            </div>

            {/* Processing state */}
            {processing && (
              <div style={S.processingBadge}>⏳ Processing...</div>
            )}

            {/* Error */}
            {error && <div style={S.errorBox}>⚠ {error}</div>}
          </div>

          {/* Result area */}
          {result && (
            <>
              <div style={S.divider} />
              <div style={S.resultSection}>
                <div style={S.resultLabel}>Result:</div>
                <div style={S.resultBox}>{result}</div>
                <button style={S.copyBtn} onClick={copyResult}>
                  {copied ? '✓ Copied!' : '⎘ Copy Result'}
                </button>
              </div>
            </>
          )}
        </>
      )}
    </div>
  );
}

createRoot(document.getElementById('app')!).render(<Popup />);