`;
const systemPrompt = "You are an expert email marketer and copywriter specializing in personalization. Your task is to generate 5 to 7 compelling, personalized email subject lines based on the user's base subject, target audience, and goal. Ensure the subject lines are concise and designed to maximize open rates. Respond only with a valid JSON object matching the provided schema.";
const userPrompt = `Base Subject: "${inputsData.baseSubject}", Target Audience: "${inputsData.audience}", Goal: "${inputsData.goal}"`;
const jsonSchema = {
type: "OBJECT",
properties: {
subject_lines: {
type: "ARRAY",
items: {
type: "OBJECT",
properties: {
subject: { type: "STRING" }
},
required: ["subject"]
}
}
},
required: ["subject_lines"]
};
const apiKey = "";
const apiUrl = `https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-preview-05-20:generateContent?key=${apiKey}`;
const payload = {
contents: [{ parts: [{ text: userPrompt }] }],
systemInstruction: { parts: [{ text: systemPrompt }] },
generationConfig: { responseMimeType: "application/json", responseSchema: jsonSchema }
};
try {
const response = await fetch(apiUrl, { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify(payload) });
if (!response.ok) throw new Error(`API Error: ${response.statusText}`);
const result = await response.json();
const aiResult = JSON.parse(result.candidates?.[0]?.content?.parts?.[0]?.text);
if (aiResult.subject_lines && aiResult.subject_lines.length > 0) {
generatedSubjects = aiResult.subject_lines.map(item => item.subject);
renderSubjects();
} else {
throw new Error("No subject lines were generated.");
}
} catch (error) {
console.error("Content generation error:", error);
resultsContainer.innerHTML = `
An error occurred: ${error.message}
`;
showNotification("Error generating content.");
} finally {
generateBtn.disabled = false;
generateBtn.textContent = 'Generate Subjects';
}
}
function renderSubjects() {
resultsContainer.innerHTML = generatedSubjects.map((subject, index) => `
`).join('');
}
// --- UTILITY FUNCTIONS ---
function showNotification(message) {
notification.textContent = message;
notification.classList.remove('opacity-0');
setTimeout(() => notification.classList.add('opacity-0'), 2000);
}
function copyToClipboard(text, message) {
navigator.clipboard.writeText(text).then(() => showNotification(message));
}
// --- PDF GENERATION ---
async function generatePdfReport() {
if (generatedSubjects.length === 0) {
showNotification("No subjects to export.");
return;
}
downloadPdfBtn.disabled = true;
downloadPdfBtn.textContent = '...';
const subjectCards = generatedSubjects.map((subject, index) => `
`).join('');
const reportHtml = `
Campaign Details
Base Subject: ${inputsData.baseSubject}
Goal: ${inputsData.goal}
Generated Subject Lines
${subjectCards}
`;
const pdfTemplate = document.getElementById('pdf-template');
pdfTemplate.innerHTML = reportHtml;
pdfTemplate.classList.remove('invisible');
try {
const { jsPDF } = window.jspdf;
const canvas = await html2canvas(pdfTemplate.querySelector('.pdf-page'), { scale: 2 });
const imgData = canvas.toDataURL('image/png');
const pdf = new jsPDF({ orientation: 'p', unit: 'pt', format: 'a4' });
const pdfWidth = pdf.internal.pageSize.getWidth(), pdfHeight = (canvas.height * pdfWidth) / canvas.width;
pdf.addImage(imgData, 'PNG', 0, 0, pdfWidth, pdfHeight);
pdf.save(`Email_Subjects_${inputsData.audience.replace(/\s+/g, '_').substring(0,20)}.pdf`);
} catch (e) { console.error('PDF Generation Error:', e); } finally {
downloadPdfBtn.disabled = false;
downloadPdfBtn.textContent = 'Download PDF';
pdfTemplate.classList.add('invisible');
pdfTemplate.innerHTML = '';
}
}
// --- EVENT LISTENERS ---
generateBtn.addEventListener('click', generateSubjects);
copyAllBtn.addEventListener('click', () => {
if (generatedSubjects.length > 0) {
const allText = generatedSubjects.join('\n');
copyToClipboard(allText, 'All subjects copied!');
}
});
resultsContainer.addEventListener('click', (e) => {
if (e.target.classList.contains('copy-subject-btn')) {
const text = generatedSubjects[e.target.dataset.index];
copyToClipboard(text, 'Subject copied!');
}
});
downloadPdfBtn.addEventListener('click', generatePdfReport);
});
