from __future__ import annotations

import argparse
from pathlib import Path

from .economics import build_snapshot
from .load import (
    default_data_dir,
    load_costs,
    load_membership,
    load_pricing_models,
    load_product,
    load_revenue,
)
from .models import EconomicsSnapshot, PricingModel, Product


def render_dashboard(
    product: Product,
    models: list[PricingModel],
    snapshot: EconomicsSnapshot,
) -> str:
    active = next(m for m in models if m.id == product.active_pricing_model_id)
    registry_lines = "\n".join(
        f"| {model.id} | {model.name} | {model.model_type} | {model.status} |"
        for model in models
    )
    return f"""# Economics Dashboard v1 — {product.name}

**Period:** {snapshot.period}  
**Lifecycle phase:** {product.lifecycle_phase}  
**Active pricing model:** {active.name} ({active.access_fee_amount} {active.currency}/{active.access_fee_cadence})

## Key Metrics

| Metric | Value |
|--------|------:|
| Active members | {snapshot.active_members} |
| Monthly revenue | {snapshot.monthly_revenue} {snapshot.currency} |
| Monthly cost | {snapshot.monthly_cost} {snapshot.currency} |
| Cost per member | {snapshot.cost_per_member} {snapshot.currency} |
| Gross margin | {snapshot.gross_margin} {snapshot.currency} |
| Gross margin % | {snapshot.gross_margin_pct}% |

_Revenue source: {snapshot.revenue_source}_

## Pricing Model Registry

| ID | Name | Type | Status |
|----|------|------|--------|
{registry_lines}

## Registries Loaded

- Product model (`data/product.json`)
- Pricing model registry (`data/pricing-models.json`)
- Cost registry (`data/costs.json`)
- Revenue registry (`data/revenue.json`)
- Membership registry (`data/membership.json`)
"""


def generate_dashboard(data_dir: Path | None = None, period: str | None = None) -> str:
    root = data_dir or default_data_dir()
    product = load_product(root)
    models = load_pricing_models(root)
    members = load_membership(root)
    revenue = load_revenue(root)
    cost_period, costs, fx_rates = load_costs(root)
    target_period = period or cost_period

    snapshot = build_snapshot(
        target_period,
        product,
        models,
        members,
        revenue,
        costs,
        fx_rates,
    )
    return render_dashboard(product, models, snapshot)


def main(argv: list[str] | None = None) -> int:
    parser = argparse.ArgumentParser(description="Coulomb Social Economics Dashboard v1")
    parser.add_argument("--data-dir", type=Path, default=None, help="Registry data directory")
    parser.add_argument("--period", default=None, help="Reporting period (YYYY-MM)")
    parser.add_argument(
        "--output",
        type=Path,
        default=None,
        help="Write Markdown report to this path (default: stdout only)",
    )
    args = parser.parse_args(argv)

    report = generate_dashboard(args.data_dir, args.period)
    if args.output:
        args.output.parent.mkdir(parents=True, exist_ok=True)
        args.output.write_text(report, encoding="utf-8")
        print(f"Wrote {args.output}")
    else:
        print(report)
    return 0


if __name__ == "__main__":
    raise SystemExit(main())