"""Pricing post-processor computing costs per model and totals."""
from config import settings
from ..context import RunContext


class PricingProcessor:
    name = "pricing"

    def process(self, ctx: RunContext) -> None:
        currency = getattr(settings, "currency", "EUR")
        pricing_cfg = getattr(settings, "pricing", {})

        by_model = {}
        total_cost = 0.0

        for model_id, usage in ctx.usage_by_model.items():
            cfg = pricing_cfg.get(model_id) or {}
            # Prefer per-million token pricing; fallback to per-1k if provided
            in_rate_1m = cfg.get("input_per_1m")
            out_rate_1m = cfg.get("output_per_1m")
            if in_rate_1m is None and cfg.get("input_per_1k") is not None:
                in_rate_1m = float(cfg.get("input_per_1k")) * 1000.0
            if out_rate_1m is None and cfg.get("output_per_1k") is not None:
                out_rate_1m = float(cfg.get("output_per_1k")) * 1000.0

            in_rate_1m = float(in_rate_1m or 0)
            out_rate_1m = float(out_rate_1m or 0)

            cost_in = (usage.get("input_tokens", 0) / 1_000_000.0) * in_rate_1m
            cost_out = (usage.get("output_tokens", 0) / 1_000_000.0) * out_rate_1m
            model_total = cost_in + cost_out
            by_model[model_id] = {
                "input": round(cost_in, 6),
                "output": round(cost_out, 6),
                "total": round(model_total, 6),
            }
            total_cost += model_total

        ctx.metadata_out["pricing"] = {
            "currency": currency,
            "total_cost": round(total_cost, 6),
            "by_model": by_model,
        }