opencrabs 0.5.4

//! Pricing fallback ladder (#655) + conservative default floor (#1717).
//!
//! A model not in the pricing table must not silently cost $0 when its family
//! is recognizable. `estimate_cost` / `calculate_cost_with_cache` resolve via a
//! ladder: exact substring, then a version-agnostic tier match so a new release
//! inherits the last-known price of its tier, then a family-root flagship
//! fallback. The ladder's bottom rung (#1717) is a conservative default rate
//! (never $0), reported as [`CostOrigin::Estimated`] and marked ~ in /usage.

use crate::usage::pricing::{
    CostOrigin, DEFAULT_UNKNOWN_INPUT_PER_M, DEFAULT_UNKNOWN_OUTPUT_PER_M, PricingConfig,
    PricingEntry, ProviderBlock,
};
use std::collections::HashMap;

const TOK: i64 = 1_000_000;

fn entry(prefix: &str, input: f64, output: f64) -> PricingEntry {
    PricingEntry {
        prefix: prefix.to_string(),
        input_per_m: input,
        output_per_m: output,
        cache_write_per_m: None,
        cache_read_per_m: None,
    }
}

fn cfg() -> PricingConfig {
    let mut providers = HashMap::new();
    providers.insert(
        "anthropic".to_string(),
        ProviderBlock {
            entries: vec![
                entry("claude-opus-4", 5.0, 25.0),
                entry("claude-sonnet-4", 3.0, 15.0),
                entry("claude-haiku-4", 1.0, 5.0),
            ],
        },
    );
    providers.insert(
        "openai".to_string(),
        ProviderBlock {
            entries: vec![entry("gpt-5", 1.25, 10.0)],
        },
    );
    providers.insert(
        "qwen".to_string(),
        ProviderBlock {
            entries: vec![
                entry("qwen3.6-max-preview", 1.30, 7.80),
                entry("qwen-max-preview", 1.30, 7.80),
                entry("qwen-plus", 0.50, 3.0),
            ],
        },
    );
    providers.insert(
        "minimax".to_string(),
        ProviderBlock {
            entries: vec![
                entry("minimax-m3", 0.60, 2.40),
                entry("minimax", 0.30, 1.20),
            ],
        },
    );
    PricingConfig { providers }
}

#[test]
fn exact_match_is_unchanged() {
    let c = cfg();
    // A known model still resolves to its own rate.
    let cost = c.estimate_cost("qwen3.6-max-preview", TOK);
    let expected = (TOK as f64 * 0.80 / 1e6) * 1.30 + (TOK as f64 * 0.20 / 1e6) * 7.80;
    assert!((cost - expected).abs() < 1e-9);
}

#[test]
fn new_version_inherits_last_known_tier_not_zero() {
    let c = cfg();
    // qwen3.8-max-preview is absent: fall back to the max-preview tier, not $0.
    let new = c.estimate_cost("qwen3.8-max-preview", TOK);
    assert_eq!(new, c.estimate_cost("qwen-max-preview", TOK));
    assert!(new > 0.0);
    // ...and not the cheaper plus tier.
    assert_ne!(new, c.estimate_cost("qwen-plus", TOK));
}

#[test]
fn new_version_preserves_tier_distinction() {
    let c = cfg();
    assert_eq!(
        c.estimate_cost("qwen3.9-plus", TOK),
        c.estimate_cost("qwen-plus", TOK)
    );
    assert_ne!(
        c.estimate_cost("qwen3.9-plus", TOK),
        c.estimate_cost("qwen-max-preview", TOK)
    );
}

#[test]
fn new_opus_and_sonnet_inherit_their_own_tier() {
    let c = cfg();
    assert_eq!(
        c.estimate_cost("claude-opus-4-9", TOK),
        c.estimate_cost("claude-opus-4", TOK)
    );
    assert_eq!(
        c.estimate_cost("claude-sonnet-9-9", TOK),
        c.estimate_cost("claude-sonnet-4", TOK)
    );
    // opus tier is not sonnet tier.
    assert_ne!(
        c.estimate_cost("claude-opus-4-9", TOK),
        c.estimate_cost("claude-sonnet-4", TOK)
    );
}

#[test]
fn normalized_short_name_resolves_to_family() {
    let c = cfg();
    // "opus-4-9" dropped the vendor prefix; still resolves to the opus tier.
    assert_eq!(
        c.estimate_cost("opus-4-9", TOK),
        c.estimate_cost("claude-opus-4", TOK)
    );
}

#[test]
fn new_gpt_version_inherits_gpt_rate() {
    let c = cfg();
    assert_eq!(
        c.estimate_cost("gpt-5.3", TOK),
        c.estimate_cost("gpt-5", TOK)
    );
    assert!(c.estimate_cost("gpt-5.3", TOK) > 0.0);
}

#[test]
fn family_root_fallback_for_a_brand_new_tier() {
    let c = cfg();
    // "qwen-ultra-9" is a tier with no version-agnostic match, but the qwen
    // family flagship (most expensive = max-preview) prices it, never $0.
    let cost = c.estimate_cost("qwen-ultra-9", TOK);
    assert!(cost > 0.0);
    assert_eq!(cost, c.estimate_cost("qwen-max-preview", TOK));
}

// ── #1717: the bottom rung is a conservative default, never $0 ──────────────

#[test]
fn unrecognizable_family_bills_conservative_default_and_reports_estimated() {
    let c = cfg();
    let b = c.calculate_cost_with_cache_detailed("totally-unknown-family-xyz", 1_000, 500, 0, 0);
    assert!(b.total > 0.0, "unpriced model must never bill $0");
    assert_eq!(b.origin, CostOrigin::Estimated);
    // Pins the default rates exactly: plain input+output, no cache tokens.
    let expected = (1_000.0 / 1e6) * DEFAULT_UNKNOWN_INPUT_PER_M
        + (500.0 / 1e6) * DEFAULT_UNKNOWN_OUTPUT_PER_M;
    assert!((b.total - expected).abs() < 1e-12);

    // Same contract through the 80/20 estimator.
    let est = c.estimate_cost("totally-unknown-family-xyz", TOK);
    let expected = (TOK as f64 * 0.80 / 1e6) * DEFAULT_UNKNOWN_INPUT_PER_M
        + (TOK as f64 * 0.20 / 1e6) * DEFAULT_UNKNOWN_OUTPUT_PER_M;
    assert!((est - expected).abs() < 1e-9);
}

#[test]
fn unknown_model_cache_tokens_bill_default_cache_rates() {
    let c = cfg();
    let b = c.calculate_cost_with_cache_detailed(
        "totally-unknown-family-xyz",
        0,
        0,
        1_000_000,
        1_000_000,
    );
    assert_eq!(b.origin, CostOrigin::Estimated);
    // Cache write defaults to 1.25x input rate, cache read to 0.1x — the
    // same shape a priced entry gets, at the default input rate.
    let expected = DEFAULT_UNKNOWN_INPUT_PER_M * 1.25 + DEFAULT_UNKNOWN_INPUT_PER_M * 0.1;
    assert!((b.total - expected).abs() < 1e-12);
}

#[test]
fn cost_origin_splits_priced_from_estimated() {
    let c = cfg();
    assert_eq!(c.cost_origin("claude-sonnet-4"), CostOrigin::Priced);
    // A tier-ladder / family-flagship fallback is still a table price.
    assert_eq!(c.cost_origin("qwen3.8-max-preview"), CostOrigin::Priced);
    assert_eq!(c.cost_origin("qwen-ultra-9"), CostOrigin::Priced);
    assert_eq!(
        c.cost_origin("totally-unknown-family-xyz"),
        CostOrigin::Estimated
    );
}

#[test]
fn known_model_resolves_exactly_and_reports_priced() {
    let c = cfg();
    let b = c.calculate_cost_with_cache_detailed("claude-sonnet-4", 1_000_000, 1_000_000, 0, 0);
    assert_eq!(b.origin, CostOrigin::Priced);
    assert!((b.total - (3.0 + 15.0)).abs() < 1e-9);
}

#[test]
fn calculate_cost_with_cache_nonzero_for_new_version() {
    let c = cfg();
    let new = c.calculate_cost_with_cache("qwen3.8-max-preview", 1_000_000, 1_000_000, 0, 0);
    let known = c.calculate_cost_with_cache("qwen-max-preview", 1_000_000, 1_000_000, 0, 0);
    assert!(new > 0.0);
    assert!((new - known).abs() < 1e-9);
}