"""
gradio_ui.py  —  inline-styles only, no CSS class dependencies
Works reliably on HF Spaces where Gradio scopes/blocks external CSS.
"""

import uuid
import requests
import gradio as gr

BASE_URL = "https://vinit006-emailagentwithmemory.hf.space"

# Colors as Python constants — used in inline styles throughout
C = {
    "bg":           "#0D1117",
    "surface":      "#161B22",
    "surface2":     "#1C2333",
    "border":       "#30363D",
    "accent":       "#58A6FF",
    "accent_dim":   "#1a2738",
    "success":      "#3FB950",
    "success_dim":  "#122a18",
    "warning":      "#D29922",
    "warning_dim":  "#2c2310",
    "danger":       "#F85149",
    "danger_dim":   "#2c1414",
    "text":         "#E6EDF3",
    "muted":        "#8B949E",
    "dim":          "#6E7681",
}

# ─── HTML builders (all inline styles) ──────────────────────────

def _pill(label: str, state: str) -> str:
    """state: 'idle' | 'active' | 'done'"""
    if state == "active":
        bg, border, color = C["accent_dim"], C["accent"], C["accent"]
    elif state == "done":
        bg, border, color = C["success_dim"], C["success"], C["success"]
    else:
        bg, border, color = C["surface2"], C["border"], C["dim"]

    return (
        f'<span style="'
        f'display:inline-block;padding:4px 14px;border-radius:20px;'
        f'font-family:monospace;font-size:11px;font-weight:700;'
        f'letter-spacing:0.06em;margin-right:8px;'
        f'border:1px solid {border};color:{color};background:{bg};">'
        f'{label}</span>'
    )


def _pipeline_html(active_step: str, done_steps=None) -> str:
    done_steps = done_steps or []
    steps = ["TRIAGE", "DRAFT", "REVIEW", "SEND"]
    pills = ""
    for s in steps:
        if s == active_step:
            pills += _pill(s, "active")
        elif s in done_steps:
            pills += _pill(s, "done")
        else:
            pills += _pill(s, "idle")
    return f'<div style="padding:10px 0 6px;">{pills}</div>'


def _triage_badge_html(label: str) -> str:
    if not label:
        return ""
    if label == "FOLLOW_UP_REQUIRED":
        bg, border, color = C["warning_dim"], C["warning"], C["warning"]
    elif label == "NO_ACTION":
        bg, border, color = C["success_dim"], C["success"], C["success"]
    else:
        bg, border, color = C["accent_dim"], C["accent"], C["accent"]

    return (
        f'<div style="margin-top:6px;">'
        f'<span style="display:inline-block;font-family:monospace;font-size:12px;'
        f'font-weight:700;letter-spacing:0.05em;padding:5px 14px;border-radius:6px;'
        f'background:{bg};color:{color};border:1px solid {border};">'
        f'{label}</span></div>'
    )


def _draft_card_html(to, subject, body) -> str:
    to      = to or "—"
    subject = subject or "—"
    body    = (body or "—").replace("\n", "<br>")
    return f"""
    <div style="background:{C['surface']};border:1px solid {C['border']};
                border-radius:12px;padding:20px;margin-top:8px;">
        <div style="display:flex;gap:40px;margin-bottom:14px;flex-wrap:wrap;">
            <div>
                <div style="font-family:monospace;font-size:10px;letter-spacing:0.1em;
                            color:{C['dim']};text-transform:uppercase;margin-bottom:4px;">TO</div>
                <div style="font-family:monospace;font-size:13px;color:{C['text']};">{to}</div>
            </div>
            <div>
                <div style="font-family:monospace;font-size:10px;letter-spacing:0.1em;
                            color:{C['dim']};text-transform:uppercase;margin-bottom:4px;">SUBJECT</div>
                <div style="font-size:13px;color:{C['text']};">{subject}</div>
            </div>
        </div>
        <div style="height:1px;background:{C['border']};margin-bottom:14px;"></div>
        <div style="font-size:13px;line-height:1.75;color:{C['muted']};">{body}</div>
    </div>
    """


def _result_card_html(icon: str, title: str, detail: str, badge_html: str = "") -> str:
    return f"""
    <div style="background:{C['surface']};border:1px solid {C['border']};
                border-radius:12px;padding:40px 32px;text-align:center;margin-top:8px;">
        <div style="font-size:44px;margin-bottom:14px;">{icon}</div>
        <div style="font-size:18px;font-weight:600;color:{C['text']};margin-bottom:8px;">{title}</div>
        <div style="font-size:13px;color:{C['muted']};margin-bottom:12px;">{detail}</div>
        {badge_html}
    </div>
    """


def _status_html(msg: str, ok: bool) -> str:
    color = C["success"] if ok else C["danger"]
    icon  = "✓" if ok else "✕"
    return (
        f'<div style="margin-top:6px;font-size:13px;color:{color};font-weight:500;">'
        f'{icon} {msg}</div>'
    )


# ─── API calls ──────────────────────────────────────────────────
def api_get_user_data(user_email):
    res = requests.post(f"{BASE_URL}/get-user-data", params={"user_email": user_email})
    res.raise_for_status()
    return res.json()

def api_process_email(token, thread_id, sender_email, subject, body):
    res = requests.post(
        f"{BASE_URL}/process-email",
        headers={"Authorization": f"Bearer {token}"},
        json={"thread_id": thread_id, "sender_email_id": sender_email,
              "sender_subject": subject, "sender_email_body": body},
    )
    res.raise_for_status()
    return res.json()

def api_review_action(token, thread_id, status, feedback=None):
    payload = {"thread_id": thread_id, "status": status}
    if feedback:
        payload["feedback"] = feedback
    res = requests.post(
        f"{BASE_URL}/review-action",
        headers={"Authorization": f"Bearer {token}"},
        json=payload,
    )
    res.raise_for_status()
    return res.json()

def api_send_email(token, thread_id, command_text):
    res = requests.post(
        f"{BASE_URL}/send_email",
        headers={"Authorization": f"Bearer {token}"},
        json={"thread_id": thread_id, "human_message": command_text or "Send now."},
    )
    res.raise_for_status()
    return res.json()


# ─── Build UI ────────────────────────────────────────────────────
def build_demo() -> gr.Blocks:
    with gr.Blocks(title="Email Agent — AI Triage & Reply") as demo:

        token_state  = gr.State(None)
        thread_state = gr.State(None)

        gr.Markdown("# ⚡ Email Agent\n_AI-powered triage, drafting & sending — with a human in the loop._")

        # ── Auth ─────────────────────────────────────────────────
        with gr.Group(visible=True) as auth_group:
            gr.Markdown("### Sign In")
            with gr.Row():
                email_input = gr.Textbox(label="Your Email", placeholder="you@example.com", scale=3)
                login_btn   = gr.Button("Sign In →", variant="primary", scale=1)
            auth_status = gr.HTML("")

        # ── Workspace ────────────────────────────────────────────
        with gr.Group(visible=False) as workspace_group:

            # Session bar
            with gr.Row():
                user_pill = gr.HTML("")
                with gr.Row():
                    thread_display  = gr.Textbox(label="Thread ID", interactive=True, scale=3)
                    new_thread_btn  = gr.Button("↺ New Thread", scale=1)

            pipeline_disp     = gr.HTML(_pipeline_html("TRIAGE"))
            triage_badge_disp = gr.HTML("")
            gr.Markdown("---")

            # Step 1
            with gr.Group(visible=True) as process_group:
                gr.Markdown("### 📥 Incoming Email")
                with gr.Row():
                    sender_email   = gr.Textbox(label="From (sender email)", placeholder="sender@company.com")
                    sender_subject = gr.Textbox(label="Subject", placeholder="Email subject line")
                sender_body    = gr.Textbox(label="Email Body", lines=8,
                                            placeholder="Paste the full email body here…")
                process_btn    = gr.Button("⚡ Process Email", variant="primary")
                process_status = gr.HTML("")

            # Step 2
            with gr.Group(visible=False) as review_group:
                gr.Markdown("### ✍️ Review Draft")
                draft_html = gr.HTML("")
                with gr.Row():
                    approve_btn = gr.Button("✓ Approve & Finalize", variant="primary")
                    changes_btn = gr.Button("↺ Request Changes")
                    reject_btn  = gr.Button("✕ Reject")
                with gr.Group(visible=False) as feedback_group:
                    feedback_text       = gr.Textbox(label="Feedback for agent", lines=4,
                                                     placeholder="Tell the agent what to change…")
                    submit_feedback_btn = gr.Button("Submit Feedback & Redraft")
                review_status = gr.HTML("")

            # Step 3
            with gr.Group(visible=False) as send_group:
                gr.Markdown(
                    "### 📨 Send Command\n"
                    "Draft saved in Gmail. Give the agent a send command.\n\n"
                    "> ℹ️ The agent can only **draft** and **send** — "
                    "it cannot edit content here. This is a timing command only."
                )
                send_command = gr.Textbox(
                    label="Send Command",
                    placeholder='"send now"  /  "send later today"  /  "hold off until tomorrow"',
                )
                send_btn    = gr.Button("📨 Execute Send Command", variant="primary")
                send_status = gr.HTML("")

            # Step 4
            with gr.Group(visible=False) as result_group:
                result_html   = gr.HTML("")
                new_email_btn = gr.Button("Process Another Email", variant="primary")

        # ── on_load: fresh thread ID per browser session ─────────
        def on_load():
            tid = str(uuid.uuid4())[:8]
            return tid, tid

        demo.load(on_load, outputs=[thread_state, thread_display])

        # ── Login ─────────────────────────────────────────────────
        def do_login(email):
            if not email or "@" not in email:
                return (gr.update(), gr.update(), None,
                        _status_html("Enter a valid email address.", False), "")
            try:
                data  = api_get_user_data(email)
                token = data["token"]
                pill  = (
                    f'<div style="background:{C["accent_dim"]};border:1px solid {C["accent"]};'
                    f'border-radius:20px;padding:5px 14px;display:inline-block;'
                    f'font-family:monospace;font-size:12px;color:{C["accent"]};">'
                    f'Signed in as: {data["email"]}</div>'
                )
                return (gr.update(visible=False), gr.update(visible=True),
                        token, "", pill)
            except Exception as e:
                return (gr.update(), gr.update(), None,
                        _status_html(f"Sign-in failed: {e}", False), "")

        login_btn.click(
            do_login, inputs=[email_input],
            outputs=[auth_group, workspace_group, token_state, auth_status, user_pill],
        )

        # ── Thread ────────────────────────────────────────────────
        def new_thread():
            tid = str(uuid.uuid4())[:8]
            return tid, tid

        new_thread_btn.click(new_thread, outputs=[thread_state, thread_display])
        thread_display.change(lambda v: v, inputs=[thread_display], outputs=[thread_state])

        # ── Process Email ─────────────────────────────────────────
        def do_process(token, thread_id, s_email, s_subject, s_body):
            if not (s_email and s_subject and s_body):
                return (
                    gr.update(), gr.update(), gr.update(), gr.update(),
                    _status_html("Fill in sender email, subject, and body.", False),
                    _pipeline_html("TRIAGE"), "", "",
                )
            try:
                data  = api_process_email(token, thread_id, s_email, s_subject, s_body)
                label = data.get("triage_label", "")
                badge = _triage_badge_html(label)

                if data.get("status") == "needs_review":
                    draft = data.get("email_draft", {})
                    return (
                        gr.update(visible=False),   # process_group
                        gr.update(visible=True),    # review_group
                        gr.update(visible=False),   # send_group
                        gr.update(visible=False),   # result_group
                        "",
                        _pipeline_html("REVIEW", ["TRIAGE", "DRAFT"]),
                        badge,
                        _draft_card_html(draft.get("to"), draft.get("subject"), draft.get("body")),
                    )
                else:
                    # No follow-up needed
                    if label == "NO_ACTION":
                        icon, title, detail = "✅", "No Action Needed", "The agent filed this email. No reply required."
                    else:
                        icon  = "🚫"
                        title = "Quarantined / No Reply"
                        detail = f"The agent decided no reply is needed for this email."

                    card = _result_card_html(icon, title, detail, badge)
                    return (
                        gr.update(visible=False),
                        gr.update(visible=False),
                        gr.update(visible=False),
                        gr.update(visible=True, value=card),
                        "",
                        _pipeline_html("TRIAGE", ["TRIAGE"]),
                        badge,
                        "",
                    )
            except Exception as e:
                return (
                    gr.update(), gr.update(), gr.update(), gr.update(),
                    _status_html(f"Error: {e}", False),
                    _pipeline_html("TRIAGE"), "", "",
                )

        process_btn.click(
            do_process,
            inputs=[token_state, thread_state, sender_email, sender_subject, sender_body],
            outputs=[process_group, review_group, send_group, result_group,
                     process_status, pipeline_disp, triage_badge_disp, draft_html],
        )

        # ── Review ────────────────────────────────────────────────
        changes_btn.click(lambda: gr.update(visible=True), outputs=[feedback_group])

        def do_review(token, thread_id, status, feedback):
            try:
                data = api_review_action(token, thread_id, status, feedback)
                if data.get("status") == "needs_review":
                    draft = data.get("email_draft", {})
                    return (
                        gr.update(visible=True), gr.update(visible=False),
                        _draft_card_html(draft.get("to"), draft.get("subject"), draft.get("body")),
                        gr.update(visible=False), "",
                        _status_html("Agent redrafted — review the new version.", True),
                        _pipeline_html("REVIEW", ["TRIAGE", "DRAFT"]),
                    )
                elif data.get("draft_id"):
                    return (
                        gr.update(visible=False), gr.update(visible=True),
                        gr.update(), gr.update(visible=False), "",
                        _status_html("Draft approved — now give a send command.", True),
                        _pipeline_html("SEND", ["TRIAGE", "DRAFT", "REVIEW"]),
                    )
                else:
                    return (
                        gr.update(visible=False), gr.update(visible=True),
                        gr.update(), gr.update(visible=False), "", "",
                        _pipeline_html("SEND", ["TRIAGE", "DRAFT", "REVIEW"]),
                    )
            except Exception as e:
                return (
                    gr.update(), gr.update(), gr.update(), gr.update(), gr.update(),
                    _status_html(f"Review failed: {e}", False), gr.update(),
                )

        _rev_out = [review_group, send_group, draft_html,
                    feedback_group, feedback_text, review_status, pipeline_disp]

        approve_btn.click(lambda t, tid: do_review(t, tid, "approved", None),
                          inputs=[token_state, thread_state], outputs=_rev_out)
        reject_btn.click(lambda t, tid: do_review(t, tid, "rejected", None),
                         inputs=[token_state, thread_state], outputs=_rev_out)
        submit_feedback_btn.click(lambda t, tid, fb: do_review(t, tid, "rejected", fb),
                                  inputs=[token_state, thread_state, feedback_text],
                                  outputs=_rev_out)

        # ── Send ──────────────────────────────────────────────────
        def do_send(token, thread_id, command_text):
            try:
                data   = api_send_email(token, thread_id, command_text)
                msg_id = data.get("sent_message_id", "")
                detail = f"Message ID: {msg_id}" if msg_id else "Email dispatched successfully."
                card   = _result_card_html("📨", "Email Sent!", detail)
                return (
                    gr.update(visible=False),
                    gr.update(visible=True, value=card),
                    "",
                    _pipeline_html("SEND", ["TRIAGE", "DRAFT", "REVIEW", "SEND"]),
                )
            except Exception as e:
                return (
                    gr.update(), gr.update(),
                    _status_html(f"Send failed: {e}", False), gr.update(),
                )

        send_btn.click(
            do_send,
            inputs=[token_state, thread_state, send_command],
            outputs=[send_group, result_group, send_status, pipeline_disp],
        )

        # ── Reset ─────────────────────────────────────────────────
        def start_new():
            tid = str(uuid.uuid4())[:8]
            return (
                tid, tid,
                gr.update(visible=True), gr.update(visible=False),
                gr.update(visible=False), gr.update(visible=False),
                "", "", "", "", "",
                gr.update(visible=False), "",
                _pipeline_html("TRIAGE"), "",
            )

        new_email_btn.click(
            start_new,
            outputs=[thread_state, thread_display,
                     process_group, review_group, send_group, result_group,
                     sender_email, sender_subject, sender_body,
                     send_command, draft_html,
                     feedback_group, feedback_text,
                     pipeline_disp, triage_badge_disp],
        )

    return demo