import gradio as gr
import pandas as pd
import tempfile
import csv

from translator import translate_english_text, enforce_formal_german
from templates import TEMPLATES


# ---------------- SINGLE EMAIL ----------------
def generate_and_translate(template_name, tone, name, sender, target_language):
    template_data = TEMPLATES[template_name][tone]

    subject_en = template_data["subject"]
    body_en = template_data["body"].format(
        name=name or "there",
        sender=sender or "Your Name"
    )

    subject_tr = translate_english_text(subject_en, target_language)
    body_tr = translate_english_text(body_en, target_language)

    if target_language == "German" and tone == "Formal":
        body_tr = enforce_formal_german(body_tr)

    final_email = f"Subject: {subject_tr}\n\n{body_tr}"

    tmp = tempfile.NamedTemporaryFile(
        delete=False, suffix=".txt", mode="w", encoding="utf-8"
    )
    tmp.write(final_email)
    tmp.close()

    return subject_tr, body_tr, final_email, tmp.name


# ---------------- BATCH CSV ----------------
def batch_translate_csv(csv_file):
    if csv_file is None:
        return None

    df = pd.read_csv(csv_file.name)

    rows = []
    for _, row in df.iterrows():
        template = row["template"].strip().replace(" ", "-")
        tone = row["tone"].strip()
        name = row["name"]
        sender = row["sender"]
        language = row["language"]

        tpl = TEMPLATES[template][tone]

        subject_tr = translate_english_text(tpl["subject"], language)
        body_tr = translate_english_text(
            tpl["body"].format(name=name, sender=sender),
            language
        )

        if language == "German" and tone == "Formal":
            body_tr = enforce_formal_german(body_tr)

        rows.append({
            "template": template,
            "tone": tone,
            "name": name,
            "language": language,
            "subject": subject_tr,
            "email_body": body_tr
        })

    out_df = pd.DataFrame(rows)

    tmp = tempfile.NamedTemporaryFile(
        delete=False, suffix=".csv", mode="w", encoding="utf-8", newline=""
    )
    out_df.to_csv(
        tmp.name,
        index=False,
        encoding="utf-8-sig",
        quoting=csv.QUOTE_ALL
    )
    tmp.close()

    return tmp.name


# ---------------- UI ----------------
with gr.Blocks(
    theme=gr.themes.Soft(primary_hue="orange"),
    css=".container {max-width:1200px; margin:auto}"
) as demo:

    gr.Markdown(
        """
        # 🌍 Cross-Border Sales Email Generator
        ### Tone-aware, multilingual, production-ready
        """
    )

    with gr.Tabs():

        # ---------- SINGLE EMAIL TAB ----------
        with gr.Tab("Single Email"):
            with gr.Row():

                with gr.Column(scale=1):
                    template = gr.Dropdown(
                        choices=list(TEMPLATES.keys()),
                        label="Email Template"
                    )
                    tone = gr.Radio(
                        ["Formal", "Casual"], label="Tone", value="Formal"
                    )
                    name = gr.Textbox(label="Recipient Name")
                    sender = gr.Textbox(label="Sender Name")
                    language = gr.Dropdown(
                        choices={
                            "🇩🇪 German": "German",
                            "🇷🇺 Russian": "Russian"
                        },
                        label="Customer Language"
                    )
                    submit_btn = gr.Button("Generate & Translate", variant="primary")

                with gr.Column(scale=1):
                    subject_out = gr.Textbox(label="Translated Subject")
                    body_out = gr.Textbox(label="Translated Email Body", lines=8)
                    final_out = gr.Textbox(label="Final Email", lines=10)
                    file_out = gr.File(label="Download Email (.txt)")

            submit_btn.click(
                fn=generate_and_translate,
                inputs=[template, tone, name, sender, language],
                outputs=[subject_out, body_out, final_out, file_out]
            )

        # ---------- BATCH CSV TAB ----------
        with gr.Tab("Batch CSV"):
            csv_in = gr.File(label="Upload CSV File")
            csv_out = gr.File(label="Download Translated CSV")
            batch_btn = gr.Button("Process CSV", variant="primary")

            batch_btn.click(
                fn=batch_translate_csv,
                inputs=csv_in,
                outputs=csv_out
            )

demo.launch()