# app.py
# VisaTier — Immigration ROI Simulator (Gradio)
# • Header + Methodology + Notes (always visible)
# • Main simulator (inputs, KPI tiles, cashflow chart, CTA)
# • Country comparison block (Dubai / UK / USA / Spain / Ireland)
# • Footer
#
# Assumptions are illustrative; users can tweak via inputs.

import math
import numpy as np
import gradio as gr
import plotly.graph_objects as go

# =========================
# LOOK & FEEL
# =========================
CSS = """
:root { --vt-primary:#2563EB; --vt-accent:#10B981; --vt-danger:#EF4444; --vt-ink:#0F172A; --vt-muted:#64748B; --radius:16px; }
.gradio-container { max-width: 1160px !important; margin: 0 auto; }

/* HEADER + FOOTER */
.vt-header { background:#0F172A; color:#E2E8F0; padding:14px 18px; border-radius:12px; display:flex; align-items:center; justify-content:space-between; margin-bottom:14px; }
.vt-header .title { font-weight:800; font-size:18px; letter-spacing:0.2px; }
.vt-header .right { font-size:12px; color:#CBD5E1; }
.vt-footer { margin-top:24px; color:#94A3B8; font-size:12px; text-align:center; padding:12px; border-top:1px solid #E2E8F0; }

/* HERO / BADGES */
.vt-hero { border-radius: var(--radius); padding: 18px 20px; background: linear-gradient(135deg, rgba(37,99,235,.10), rgba(16,185,129,.10)); border: 1px solid #E2E8F0; margin-bottom:16px; }
.vt-badge { display:inline-block; font-size:12px; padding:4px 8px; border-radius:9999px; background:#E2E8F0; color:#334155; margin-right:6px; }

/* KPI */
.vt-kpi { border-radius: var(--radius); padding:16px; background:#FFFFFF; border:1px solid #E2E8F0; margin-bottom:10px; }
.vt-kpi .label { font-size:12px; color:#64748B; }
.vt-kpi .value { font-size:28px; font-weight:800; color:#0F172A; line-height:1.1; }
.vt-kpi.good .value { color: var(--vt-accent); }
.vt-kpi.warn .value { color: var(--vt-danger); }
.vt-note { font-size:12px; color:#64748B; }

/* METHOD block */
.vt-method { border-radius:12px; border:1px solid #E2E8F0; background:#FFFFFF; padding:12px 14px; margin-bottom:10px; }

/* CTA button as link */
.vt-cta { display:inline-block; background:#2563EB; color:#FFFFFF!important; padding:10px 14px; border-radius:10px; font-weight:700; text-decoration:none; margin-top:10px; }
.vt-cta:hover { background:#1D4ED8; }

.table-like { border:1px solid #E2E8F0; border-radius:12px; overflow:hidden; }
.table-like table { width:100%; border-collapse:collapse; font-size:14px; }
.table-like th, .table-like td { padding:10px 12px; border-bottom:1px solid #E2E8F0; text-align:left; }
.table-like th { background:#F8FAFC; color:#0F172A; font-weight:700; }
.table-like tr:last-child td { border-bottom: none; }
"""

THEME = gr.themes.Soft(
    primary_hue="blue",
    neutral_hue="slate"
).set(
    body_background_fill="#F8FAFC",
    body_text_color="#0F172A",
    button_primary_background_fill="#2563EB",
    button_primary_background_fill_hover="#1D4ED8",
)

BOOK_LINK = "https://calendly.com/your-team/diagnostic"  # <-- поставь свою ссылку

# =========================
# COUNTRY TEMPLATES (assumptions)
# =========================
COUNTRIES = ["UAE (Dubai)", "UK", "USA (FL/TX/NV)", "Spain", "Ireland"]

COUNTRY_CONFIG = {
    "UAE (Dubai)":   {"corp_tax": 0.09,  "pers_tax": 0.00, "rev_mult": 3.0, "margin_delta_pp": 5.0, "living_month": 9000.0, "ongoing_month": 1500.0, "setup_once": 35000.0},
    "UK":            {"corp_tax": 0.25,  "pers_tax": 0.27, "rev_mult": 1.5, "margin_delta_pp": 2.0, "living_month": 6200.0, "ongoing_month": 1100.0, "setup_once": 18000.0},
    "USA (FL/TX/NV)":{"corp_tax": 0.21,  "pers_tax": 0.22, "rev_mult": 1.8, "margin_delta_pp": 4.0, "living_month": 7000.0, "ongoing_month": 1300.0, "setup_once": 20000.0},
    "Spain":         {"corp_tax": 0.25,  "pers_tax": 0.24, "rev_mult": 1.4, "margin_delta_pp": 2.0, "living_month": 5000.0, "ongoing_month": 1000.0, "setup_once": 20000.0},
    "Ireland":       {"corp_tax": 0.125, "pers_tax": 0.22, "rev_mult": 1.6, "margin_delta_pp": 3.0, "living_month": 6500.0, "ongoing_month": 1200.0, "setup_once": 25000.0},
}

# =========================
# FINANCE HELPERS
# =========================
def clamp(x, lo, hi): return max(lo, min(hi, x))
def monthly_rate(annual_rate): return (1.0 + annual_rate) ** (1.0 / 12.0) - 1.0

def irr_bisection(cash, lo=-0.99, hi=5.0, iters=100, tol=1e-7):
    def npv(rate): return sum(cf / ((1 + rate) ** t) for t, cf in enumerate(cash))
    f_lo, f_hi = npv(lo), npv(hi)
    if f_lo * f_hi > 0: return None
    for _ in range(iters):
        mid = (lo + hi) / 2
        v = npv(mid)
        if abs(v) < tol: return mid
        if v > 0: lo = mid
        else: hi = mid
    return (lo + hi) / 2

def ramp_factor(m): return 0.6 if m <= 6 else (0.8 if m <= 12 else 1.0)

# =========================
# CORE MODEL (monthly)
# =========================
def compute_monthly_delta_cashflow(
    rev0, margin0_pct, corp0_pct, pers0_pct, living0, ongoing0,
    dest, rev_mult, margin_delta_pp, corp1_pct, pers1_pct, living1, ongoing1,
    capex_once, horizon_m, discount_annual_pct, success_pct
):
    m0 = clamp(margin0_pct / 100.0, 0.0, 0.9)
    ct0 = clamp(corp0_pct / 100.0, 0.0, 0.6)
    pt0 = clamp(pers0_pct / 100.0, 0.0, 0.6)

    mult = max(0.0, rev_mult)
    mdelta = margin_delta_pp / 100.0
    ct1 = clamp(corp1_pct / 100.0, 0.0, 0.6)
    pt1 = clamp(pers1_pct / 100.0, 0.0, 0.6)

    p = clamp(success_pct / 100.0, 0.01, 1.0)
    mr = monthly_rate(discount_annual_pct / 100.0)

    base_profit0 = rev0 * m0
    after_tax0 = base_profit0 * (1 - ct0) * (1 - pt0) - living0 - ongoing0

    rev1 = rev0 * mult
    m1 = clamp(m0 + mdelta, 0.01, 0.9)
    base_profit1 = rev1 * m1
    after_tax1 = base_profit1 * (1 - ct1) * (1 - pt1) - living1 - ongoing1

    delta_monthly = after_tax1 - after_tax0

    cash = [-capex_once]
    cum = -capex_once
    months = [0]
    cum_series = [cum]
    payback_m = math.inf

    for m in range(1, horizon_m + 1):
        cf = delta_monthly * ramp_factor(m) * p
        cash.append(cf)
        cum += cf
        months.append(m)
        cum_series.append(cum)
        if math.isinf(payback_m) and cum >= 0:
            payback_m = m

    npv = sum(cf / ((1 + mr) ** t) for t, cf in enumerate(cash))
    roi5y = (npv / capex_once * 100.0) if capex_once > 0 else (0.0 if npv <= 0 else math.inf)
    irr_m = irr_bisection(cash)
    irr_annual = ((1 + irr_m) ** 12 - 1) * 100.0 if irr_m is not None else 0.0

    return {
        "npv": npv,
        "total_5yr_roi": roi5y,
        "payback_months": payback_m,
        "payback_years": (payback_m / 12.0) if not math.isinf(payback_m) else float("inf"),
        "irr_annual_pct": irr_annual,
        "months": months,
        "cum_values": cum_series,
        "delta_monthly": delta_monthly,
    }

# =========================
# PLOTS
# =========================
def build_cashflow_chart(months, cum_values, payback_month=None):
    fig = go.Figure()
    fig.add_trace(go.Scatter(
        x=months, y=cum_values, mode="lines",
        line=dict(width=3, color="#2563EB"),
        fill='tozeroy', fillcolor="rgba(37,99,235,0.08)",
        name="Cumulative ΔCF"
    ))
    fig.add_hline(y=0, line_width=1, line_dash="dot", line_color="#94A3B8")
    if payback_month not in (None, float("inf")):
        fig.add_vline(
            x=payback_month, line_width=1, line_dash="dot", line_color="#2563EB",
            annotation_text="Break-even", annotation_position="top right"
        )
    fig.update_layout(
        margin=dict(l=20, r=20, t=30, b=20),
        xaxis_title="Month",
        yaxis_title="Cumulative €",
        plot_bgcolor="#FFFFFF",
        paper_bgcolor="#FFFFFF",
        showlegend=False,
        height=380
    )
    return fig

def build_comparison_bar(names, values, title, ytitle):
    fig = go.Figure()
    fig.add_bar(x=names, y=values, marker_color="#2563EB")
    fig.update_layout(
        title=title,
        xaxis_title="Destination",
        yaxis_title=ytitle,
        margin=dict(l=20, r=20, t=50, b=40),
        plot_bgcolor="#FFFFFF",
        paper_bgcolor="#FFFFFF",
        height=380
    )
    return fig

# =========================
# UI HELPERS
# =========================
def render_kpis(result):
    payback_years = "Never" if result["payback_years"] == float("inf") else f'{result["payback_years"]:.1f} years'
    roi_str = f'{result["total_5yr_roi"]:.1f}%'
    irr_str = f'{result["irr_annual_pct"]:.1f}%'
    npv_str = f'€{result["npv"]:,.0f}'
    k1 = f"""<div class="vt-kpi {'good' if result['payback_years']<=1.0 else ''}">
        <div class="label">Payback</div><div class="value">{payback_years}</div>
        <div class="vt-note">Time to break even</div></div>"""
    k2 = f"""<div class="vt-kpi {'good' if result['total_5yr_roi']>=100 else ''}">
        <div class="label">ROI (5y)</div><div class="value">{roi_str}</div>
        <div class="vt-note">Risk-adjusted</div></div>"""
    k3 = f"""<div class="vt-kpi">
        <div class="label">IRR (annual)</div><div class="value">{irr_str}</div>
        <div class="vt-note">From monthly cashflows</div></div>"""
    k4 = f"""<div class="vt-kpi">
        <div class="label">NPV</div><div class="value">{npv_str}</div>
        <div class="vt-note">Discounted at your rate</div></div>"""
    return k1, k2, k3, k4

# =========================
# APP LAYOUT
# =========================
def create_app():
    with gr.Blocks(css=CSS, theme=THEME) as demo:

        # HEADER
        gr.HTML("""
        <div class="vt-header">
          <div class="title">VisaTier — Immigration ROI Simulator</div>
          <div class="right">Built for founders • MVP</div>
        </div>
        """)

        # Methodology + Notes (always visible)
        gr.HTML("""
        <div class="vt-method">
          <b>Methodology</b><br/>
          How we calculate (simplified):<br/>
          • Baseline owner cashflow = after corporate & personal taxes – living – ongoing.<br/>
          • Scenario = revenue × multiplier, margin delta, destination taxes & living.<br/>
          • Monthly uplift ΔCF → cumulative cashflow → Payback, ROI, IRR, NPV.<br/>
          • Risk‑adjusted (success probability), discounted at your chosen rate.
        </div>
        """)
        gr.HTML("""
        <div class="vt-note"><b>Notes:</b> Illustrative model, not tax or legal advice. Results depend on execution and personal circumstances.</div>
        """)

        # HERO
        gr.HTML("""
        <div class="vt-hero">
          <h2 style="margin:0; font-size:22px; font-weight:800; color:#0F172A;">Model the financial impact of relocation</h2>
          <p style="margin:6px 0 10px; color:#334155;">Simulate revenue lift, taxes and living costs — get a risk‑adjusted payback date in minutes.</p>
          <span class="vt-badge">MVP</span>
          <span class="vt-badge">Founders</span>
          <span class="vt-badge">Free to try</span>
        </div>
        """)

        # ===== MAIN SIMULATOR =====
        with gr.Row():
            with gr.Column(scale=5):
                dest = gr.Dropdown(COUNTRIES, value="UAE (Dubai)", label="Destination template")

                with gr.Row():
                    rev0 = gr.Number(value=30000, label="Baseline revenue (€/month)")
                    margin0 = gr.Slider(value=25, minimum=1, maximum=70, step=1, label="Baseline EBITDA margin (%)")
                with gr.Row():
                    corp0 = gr.Slider(value=20, minimum=0, maximum=50, step=1, label="Baseline corporate tax (%)")
                    pers0 = gr.Slider(value=10, minimum=0, maximum=50, step=1, label="Baseline personal tax (%)")
                with gr.Row():
                    living0 = gr.Number(value=4000, label="Baseline living cost (€/month)")
                    ongoing0 = gr.Number(value=0, label="Other ongoing (€/month)")

                gr.Markdown("**Destination adjustments**")
                with gr.Row():
                    rev_mult = gr.Slider(value=3.0, minimum=0.5, maximum=5.0, step=0.1, label="Revenue multiplier (×)")
                    margin_delta = gr.Slider(value=5.0, minimum=-20, maximum=30, step=0.5, label="Margin delta (pp)")
                with gr.Row():
                    corp1 = gr.Slider(value=9, minimum=0, maximum=50, step=1, label="Destination corporate tax (%)")
                    pers1 = gr.Slider(value=0, minimum=0, maximum=50, step=1, label="Destination personal tax (%)")
                with gr.Row():
                    living1 = gr.Number(value=9000, label="Destination living cost (€/month)")
                    ongoing1 = gr.Number(value=1500, label="Other ongoing (€/month)")

                with gr.Accordion("Investments & risk", open=False):
                    with gr.Row():
                        capex_once = gr.Number(value=35000, label="One-time setup (€)")
                        horizon_m = gr.Slider(value=36, minimum=6, maximum=60, step=1, label="Horizon (months)")
                    with gr.Row():
                        discount_a = gr.Slider(value=12, minimum=0, maximum=40, step=1, label="Annual discount rate (%)")
                        success = gr.Slider(value=75, minimum=10, maximum=100, step=1, label="Success probability (%)")

                estimate_btn = gr.Button("Estimate", variant="primary")

            with gr.Column(scale=7):
                gr.Markdown("**Results (teaser)** — first 2 KPIs.")
                kpi1 = gr.HTML("<div class='vt-kpi'><div class='label'>Payback</div><div class='value'>—</div><div class='vt-note'>Time to break even</div></div>")
                kpi2 = gr.HTML("<div class='vt-kpi'><div class='label'>ROI (5y)</div><div class='value'>—</div><div class='vt-note'>Risk-adjusted</div></div>")
                kpi3 = gr.HTML("<div class='vt-kpi'><div class='label'>IRR (annual)</div><div class='value'>—</div><div class='vt-note'>From monthly cashflows</div></div>", visible=False)
                kpi4 = gr.HTML("<div class='vt-kpi'><div class='label'>NPV</div><div class='value'>—</div><div class='vt-note'>Discounted at your rate</div></div>", visible=False)

                chart = gr.Plot(visible=False)
                cta_btn = gr.HTML(f'<a class="vt-cta" href="{BOOK_LINK}" target="_blank">Book diagnostic</a>', visible=False)

                state_result = gr.State(value=None)
                state_unlocked = gr.State(value=False)

                def on_estimate(
                    dest, rev0, margin0, corp0, pers0, living0, ongoing0,
                    rev_mult, margin_delta, corp1, pers1, living1, ongoing1,
                    capex_once, horizon_m, discount_a, success
                ):
                    # Apply template defaults if user left UAE defaults
                    if dest in COUNTRY_CONFIG:
                        cfg = COUNTRY_CONFIG[dest]
                        # if user did not change from UAE defaults, swap to chosen
                        if dest != "UAE (Dubai)":
                            if rev_mult == 3.0: rev_mult = cfg["rev_mult"]
                            if margin_delta == 5.0: margin_delta = cfg["margin_delta_pp"]
                            if corp1 == 9: corp1 = cfg["corp_tax"] * 100.0
                            if pers1 == 0: pers1 = cfg["pers_tax"] * 100.0
                            if living1 == 9000: living1 = cfg["living_month"]
                            if ongoing1 == 1500: ongoing1 = cfg["ongoing_month"]
                            if capex_once == 35000: capex_once = cfg["setup_once"]

                    result = compute_monthly_delta_cashflow(
                        rev0, margin0, corp0, pers0, living0, ongoing0,
                        dest, rev_mult, margin_delta, corp1, pers1, living1, ongoing1,
                        capex_once, int(horizon_m), discount_a, success
                    )
                    k1, k2, k3, k4 = render_kpis(result)
                    return (
                        k1, k2, k3, k4,
                        build_cashflow_chart(result["months"], result["cum_values"], result["payback_months"]),
                        result, True
                    )

                estimate_btn.click(
                    on_estimate,
                    inputs=[dest, rev0, margin0, corp0, pers0, living0, ongoing0,
                            rev_mult, margin_delta, corp1, pers1, living1, ongoing1,
                            capex_once, horizon_m, discount_a, success],
                    outputs=[kpi1, kpi2, kpi3, kpi4, chart, state_result, cta_btn]
                )

        # ===== COMPARISON BLOCK =====
        gr.Markdown("## Compare destinations — Dubai / UK / USA / Spain / Ireland")

        with gr.Row():
            with gr.Column(scale=5):
                gr.Markdown("**Assumptions shared across comparison** (you can tweak):")
                rev0_c = gr.Number(value=30000, label="Baseline revenue (€/month)")
                margin0_c = gr.Slider(value=25, minimum=1, maximum=70, step=1, label="Baseline EBITDA margin (%)")
                corp0_c = gr.Slider(value=20, minimum=0, maximum=50, step=1, label="Baseline corporate tax (%)")
                pers0_c = gr.Slider(value=10, minimum=0, maximum=50, step=1, label="Baseline personal tax (%)")
                living0_c = gr.Number(value=4000, label="Baseline living cost (€/month)")
                ongoing0_c = gr.Number(value=0, label="Other ongoing (€/month)")
                with gr.Row():
                    capex_c = gr.Number(value=30000, label="One-time setup (€)")
                    horizon_c = gr.Slider(value=36, minimum=6, maximum=60, step=1, label="Horizon (months)")
                with gr.Row():
                    discount_c = gr.Slider(value=12, minimum=0, maximum=40, step=1, label="Annual discount rate (%)")
                    success_c = gr.Slider(value=75, minimum=10, maximum=100, step=1, label="Success probability (%)")

                compare_btn = gr.Button("Run comparison", variant="primary")

            with gr.Column(scale=7):
                comp_kpis = gr.HTML("<div class='table-like'><table><tr><th>Destination</th><th>Payback (yrs)</th><th>ROI (5y)</th><th>IRR (annual)</th><th>NPV (€)</th></tr></table></div>")
                comp_bar_roi = gr.Plot()
                comp_bar_payback = gr.Plot()

                def run_comparison(rev0, margin0, corp0, pers0, living0, ongoing0, capex, horizon, discount, success):
                    rows = []
                    roi_vals = []
                    payback_vals = []
                    for name in COUNTRIES:
                        cfg = COUNTRY_CONFIG[name]
                        res = compute_monthly_delta_cashflow(
                            rev0, margin0, corp0, pers0, living0, ongoing0,
                            name, cfg["rev_mult"], cfg["margin_delta_pp"], cfg["corp_tax"]*100.0, cfg["pers_tax"]*100.0,
                            cfg["living_month"], cfg["ongoing_month"],
                            cfg["setup_once"] if capex == 30000 else capex,  # если не трогали — можно оставить шаблонный setup
                            int(horizon), discount, success
                        )
                        pb = "Never" if res["payback_years"] == float("inf") else f"{res['payback_years']:.1f}"
                        rows.append(f"<tr><td><b>{name}</b></td><td>{pb}</td><td>{res['total_5yr_roi']:.1f}%</td><td>{res['irr_annual_pct']:.1f}%</td><td>€{res['npv']:,.0f}</td></tr>")
                        roi_vals.append(res["total_5yr_roi"])
                        payback_vals.append(res["payback_years"] if res["payback_years"] != float("inf") else None)

                    table_html = "<div class='table-like'><table><tr><th>Destination</th><th>Payback (yrs)</th><th>ROI (5y)</th><th>IRR (annual)</th><th>NPV (€)</th></tr>" + "".join(rows) + "</table></div>"
                    bar_roi = build_comparison_bar(COUNTRIES, roi_vals, "ROI (5y) by destination", "ROI %")
                    # For payback: set large number for None to visualize; but better leave None & Plotly will skip
                    pb_plot_vals = [v if v is not None else None for v in payback_vals]
                    bar_payback = build_comparison_bar(COUNTRIES, pb_plot_vals, "Payback (years) by destination", "Years")

                    return table_html, bar_roi, bar_payback

                compare_btn.click(
                    run_comparison,
                    inputs=[rev0_c, margin0_c, corp0_c, pers0_c, living0_c, ongoing0_c, capex_c, horizon_c, discount_c, success_c],
                    outputs=[comp_kpis, comp_bar_roi, comp_bar_payback]
                )

        # FOOTER
        gr.HTML("""<div class="vt-footer">© 2025 VisaTier — Immigration & Investment Advisory • <a href="https://visatier.com" target="_blank">visatier.com</a> • <a href='{}' target='_blank'>Book diagnostic</a></div>""".format(BOOK_LINK))

    return demo

# HF expects a global `demo`
demo = create_app()

if __name__ == "__main__":
    demo.launch()