'use strict';
/**
 * paste_create.js — Logic for the paste creation page.
 * Depends on: crypto.js (PasteCrypto), app.js (clearDraft, window.PBCFG)
 */

document.addEventListener('DOMContentLoaded', function () {
    const textarea   = document.getElementById('content');
    const submitBtn  = document.getElementById('submitBtn');
    const langSelect = document.getElementById('language');

    // ── Password modal state ─────────────────────────────────────────────────
    let _pendingPassword = null; // set when user locks paste

    const passwordBtn    = document.getElementById('passwordBtn');
    const passwordModal  = document.getElementById('passwordModal');
    const ppInput        = document.getElementById('pastePassword');
    const ppConfirm      = document.getElementById('pastePasswordConfirm');
    const ppError        = document.getElementById('passwordModalError');
    const ppSave         = document.getElementById('passwordModalSave');
    const ppCancel       = document.getElementById('passwordModalCancel');
    const ppClear        = document.getElementById('passwordModalClear');

    function openPasswordModal() {
        ppInput.value   = '';
        ppConfirm.value = '';
        ppError.style.display = 'none';
        passwordModal.style.display = 'flex';
        ppInput.focus();
    }
    function closePasswordModal() {
        passwordModal.style.display = 'none';
    }
    function updatePasswordBtn() {
        if (_pendingPassword) {
            passwordBtn.textContent = '\uD83D\uDD13 Locked';
            passwordBtn.classList.add('nav-btn-locked');
        } else {
            passwordBtn.textContent = '\uD83D\uDD12 Lock';
            passwordBtn.classList.remove('nav-btn-locked');
        }
    }

    if (passwordBtn) passwordBtn.addEventListener('click', openPasswordModal);
    if (ppCancel)    ppCancel.addEventListener('click', closePasswordModal);
    if (ppClear) {
        ppClear.addEventListener('click', () => {
            _pendingPassword = null;
            updatePasswordBtn();
            closePasswordModal();
        });
    }
    if (ppSave) {
        ppSave.addEventListener('click', () => {
            const pw  = ppInput.value;
            const pw2 = ppConfirm.value;
            if (!pw) { ppError.textContent = 'Password cannot be empty.'; ppError.style.display = 'block'; return; }
            if (pw !== pw2) { ppError.textContent = 'Passwords do not match.'; ppError.style.display = 'block'; return; }
            _pendingPassword = pw;
            updatePasswordBtn();
            closePasswordModal();
        });
    }
    // Close modal on overlay click
    if (passwordModal) {
        passwordModal.addEventListener('click', (e) => { if (e.target === passwordModal) closePasswordModal(); });
    }
    // Allow Enter to confirm password modal
    [ppInput, ppConfirm].forEach(el => {
        if (el) el.addEventListener('keydown', e => { if (e.key === 'Enter') ppSave?.click(); });
    });

    // ── Load languages from API ──────────────────────────────────────────────
    fetch('/api/languages')
        .then(r => r.json())
        .then(langs => {
            langSelect.innerHTML = '';
            langs.forEach(l => {
                const o = document.createElement('option');
                o.value = l.value;
                o.textContent = l.name;
                langSelect.appendChild(o);
            });
            // Restore last-used language preference
            const saved = localStorage.getItem('preferred_language');
            if (saved) langSelect.value = saved;
        })
        .catch(() => {});

    langSelect.addEventListener('change', () =>
        localStorage.setItem('preferred_language', langSelect.value));

    // ── Restore expiry preference ────────────────────────────────────────────
    const expirySelect = document.getElementById('expires_in');
    const savedExpiry  = localStorage.getItem('preferred_expiry');
    if (savedExpiry) expirySelect.value = savedExpiry;
    expirySelect.addEventListener('change', () =>
        localStorage.setItem('preferred_expiry', expirySelect.value));

    // ── Restore discussions preference ───────────────────────────────────────
    const discussCheck = document.getElementById('allowDiscussions');
    if (discussCheck) {
        discussCheck.checked = localStorage.getItem('preferred_discussions') === 'true';
        discussCheck.addEventListener('change', () =>
            localStorage.setItem('preferred_discussions', discussCheck.checked));
    }

    // Burn-after-read — intentionally NOT persisted to localStorage.
    const burnCheck = document.getElementById('burnAfterRead');

    // ── Ctrl/Cmd+S shortcut ──────────────────────────────────────────────────
    document.addEventListener('keydown', e => {
        if ((e.ctrlKey || e.metaKey) && e.key === 's') {
            e.preventDefault();
            submitPaste();
        }
    });

    submitBtn.addEventListener('click', submitPaste);

    // ── Clear Draft ──────────────────────────────────────────────────────────
    const clearBtn = document.getElementById('clearBtn');
    if (clearBtn) {
        clearBtn.addEventListener('click', () => {
            console.log('[Clear] Manual clear requested.');
            
            // Clear the editor and title
            textarea.value = '';
            const title = document.getElementById('title');
            if (title) title.value = '';
            
            // Wipe the localStorage draft via the global helper in app.js
            if (typeof window.clearDraft === 'function') {
                window.clearDraft();
            } else {
                localStorage.removeItem('paste_draft');
            }
            
            textarea.focus();
            console.log('[Clear] Draft wiped.');
        });
    }

    // ── Submit ───────────────────────────────────────────────────────────────

    async function submitPaste() {
        const content    = textarea.value;
        const title      = document.getElementById('title').value || 'Untitled';
        const language   = langSelect.value;
        const expires_in = expirySelect.value;

        if (!content.trim()) { textarea.focus(); return; }

        // Read E2E flag from the already-loaded config (fetched by app.js at startup).
        // By the time the user clicks Save, window.PBCFG is guaranteed to be populated.
        const E2E = window.PBCFG?.features?.encrypt_pastes ?? true;
        const discussions    = document.getElementById('allowDiscussions')?.checked ?? false;
        const burn_after_read = burnCheck?.checked ?? false;

        submitBtn.disabled    = true;
        submitBtn.textContent = '…';

        try {
            let postBody, keyBase64 = null;
            if (E2E) {
                let key, fragmentValue;
                if (_pendingPassword) {
                    // Password-based: derive key from password via PBKDF2.
                    // Fragment is "p:<salt>" — no raw key in the URL.
                    const { key: derivedKey, saltBase64url } = await PasteCrypto.deriveKeyFromPassword(_pendingPassword);
                    key           = derivedKey;
                    fragmentValue = 'p:' + saltBase64url;
                } else {
                    // Normal: random key, fragment is the key itself.
                    const keyLen = window.PBCFG?.pastes?.encryption_key_bits ?? 128;
                    key           = await PasteCrypto.generateKey(keyLen);
                    keyBase64     = await PasteCrypto.exportKey(key);
                    fragmentValue = keyBase64;
                }
                const plain = JSON.stringify({ title, content, language, discussions, password_protected: !!_pendingPassword });
                postBody = { encrypted_data: await PasteCrypto.encrypt(plain, key), expires_in, discussions, burn_after_read };
                keyBase64 = fragmentValue;
            } else {
                postBody = { title, content, language, expires_in, discussions, burn_after_read };
            }

            const resp   = await fetch('/create', {
                method:  'POST',
                headers: { 'Content-Type': 'application/json' },
                body:    JSON.stringify(postBody),
            });
            const result = await resp.json();

            if (result.error) {
                alert('Error: ' + result.error);
                submitBtn.disabled    = false;
                submitBtn.textContent = 'Save';
            } else {
                if (typeof window.clearDraft === 'function') {
                    window.clearDraft();
                }
                if (result.deletion_token) {
                    localStorage.setItem('del_' + result.paste_id, result.deletion_token);
                }

                const shareUrl = window.location.origin + result.url + (keyBase64 ? '#' + keyBase64 : '');

                if (burn_after_read) {
                    // Don't navigate — creator must NOT open the paste or it burns.
                    // Show a share panel so they can copy the link and hand it to the recipient.
                    showBurnSharePanel(shareUrl);
                } else {
                    window.location.href = shareUrl;
                }
            }
        } catch (err) {
            console.error(err);
            alert('Failed to create paste. Try again.');
            submitBtn.disabled    = false;
            submitBtn.textContent = 'Save';
        }
    }

    function showBurnSharePanel(url) {
        // Hide the editor so the user can't accidentally re-submit
        const editorEl = document.getElementById('content');
        if (editorEl) editorEl.style.display = 'none';
        // Hide nav controls (keep theme toggle visible)
        document.querySelectorAll('.nav-links > *:not(.theme-toggle)').forEach(el => {
            el.style.visibility = 'hidden';
        });

        // Populate and show the panel
        const panel  = document.getElementById('burnSharePanel');
        const urlEl  = document.getElementById('burnShareUrl');
        const copyEl = document.getElementById('burnShareCopy');
        if (!panel || !urlEl || !copyEl) return;

        urlEl.value = url;
        panel.style.display = 'flex';

        // Auto-select the URL for easy manual copying
        urlEl.focus();
        urlEl.select();

        copyEl.addEventListener('click', async () => {
            const ok = typeof copyToClipboard === 'function'
                ? await copyToClipboard(url)
                : await navigator.clipboard?.writeText(url).then(() => true).catch(() => false);
            const prev = copyEl.textContent;
            copyEl.textContent = ok ? 'Copied!' : 'Failed';
            setTimeout(() => { copyEl.textContent = prev; }, 1800);
        });
    }
});