// Claude 辅助函数
// JSON Schema 清理、签名处理等

// 已移除未使用的 Value 导入

/// 将 JSON Schema 中的类型名称转为大写 (Gemini 要求)
/// 例如: "string" -> "STRING", "integer" -> "INTEGER"
// 已移除未使用的 uppercase_schema_types 函数

/// 根据模型名称获取上下文 Token 限制
pub fn get_context_limit_for_model(model: &str) -> u32 {
    if model.contains("pro") {
        2_097_152 // 2M for Pro
    } else if model.contains("flash") {
        1_048_576 // 1M for Flash
    } else {
        1_048_576 // Default 1M
    }
}

pub fn to_claude_usage(usage_metadata: &super::models::UsageMetadata, scaling_enabled: bool, context_limit: u32) -> super::models::Usage {
    let prompt_tokens = usage_metadata.prompt_token_count.unwrap_or(0);
    let cached_tokens = usage_metadata.cached_content_token_count.unwrap_or(0);

    // 【改进的智能阈值回归算法】
    // 目标：既利用 Gemini 大窗口，又能在高用量时让 Claude Code 正确触发 compact 提示
    //
    // 分阶段策略：
    // - 0-50%:  激进压缩，享受大上下文
    // - 50-70%: 开始加速回升
    // - 70-85%: 快速回升到显示 70%+
    // - 85%+:   接近 1:1 显示，确保触发 Claude Code 的 compact 提示
    let total_raw = prompt_tokens;

    // [FIX] Restore low token threshold - don't scale if under 30k tokens
    const SCALING_THRESHOLD: u32 = 30_000;

    let scaled_total = if scaling_enabled && total_raw > SCALING_THRESHOLD {
        const TARGET_MAX: f64 = 195_000.0; // 接近 Claude 的 200k 限制

        let ratio = total_raw as f64 / context_limit as f64;

        if ratio <= 0.5 {
            // 阶段1 (0-50%): 激进压缩，享受大上下文
            // 真实 50% → 显示 ~30%
            let display_ratio = ratio * 0.6;
            (display_ratio * TARGET_MAX) as u32
        } else if ratio <= 0.7 {
            // 阶段2 (50-70%): 开始加速回升
            // 线性从 30% 回升到 50%
            let progress = (ratio - 0.5) / 0.2;
            let display_ratio = 0.3 + progress * 0.2;
            (display_ratio * TARGET_MAX) as u32
        } else if ratio <= 0.85 {
            // 阶段3 (70-85%): 快速回升到显示 70%
            // 这个阶段让用户开始注意到上下文在增长
            let progress = (ratio - 0.7) / 0.15;
            let display_ratio = 0.5 + progress * 0.2;
            (display_ratio * TARGET_MAX) as u32
        } else {
            // 阶段4 (85%+): 接近 1:1 显示，触发 Claude Code 的 compact 提示
            // 85% 真实 → 70% 显示
            // 100% 真实 → 97% 显示
            let progress = (ratio - 0.85) / 0.15;
            let display_ratio = 0.7 + progress * 0.27;
            (display_ratio.min(0.97) * TARGET_MAX) as u32
        }
    } else {
        total_raw
    };

    // 【调试日志】方便手动验证
    if scaling_enabled && total_raw > 30_000 {
        let ratio = total_raw as f64 / context_limit as f64;
        let display_ratio = scaled_total as f64 / 195_000.0;
        tracing::debug!(
            "[Claude-Scaling] Raw: {} ({:.1}%), Display: {} ({:.1}%), Compression: {:.1}x",
            total_raw, ratio * 100.0, scaled_total, display_ratio * 100.0,
            total_raw as f64 / scaled_total as f64
        );
    }
    
    // 按比例分配缩放后的总量到 input 和 cache_read
    let (reported_input, reported_cache) = if total_raw > 0 {
        let cache_ratio = (cached_tokens as f64) / (total_raw as f64);
        let sc_cache = (scaled_total as f64 * cache_ratio) as u32;
        (scaled_total.saturating_sub(sc_cache), Some(sc_cache))
    } else {
        (scaled_total, None)
    };
    
    super::models::Usage {
        input_tokens: reported_input,
        output_tokens: usage_metadata.candidates_token_count.unwrap_or(0),
        cache_read_input_tokens: reported_cache,
        cache_creation_input_tokens: Some(0),
        server_tool_use: None,
    }
}

/// 提取 thoughtSignature
// 已移除未使用的 extract_thought_signature 函数

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_to_claude_usage() {
        use super::super::models::UsageMetadata;

        let usage = UsageMetadata {
            prompt_token_count: Some(100),
            candidates_token_count: Some(50),
            total_token_count: Some(150),
            cached_content_token_count: None,
        };

        let claude_usage = to_claude_usage(&usage, true, 1_000_000);
        // 100 tokens is < 30k, minimal scaling
        assert!(claude_usage.input_tokens < 200);
        assert_eq!(claude_usage.output_tokens, 50);

        // 测试 50% 负载 (500k) - 应该显示 ~30%
        let usage_50 = UsageMetadata {
            prompt_token_count: Some(500_000),
            candidates_token_count: Some(10),
            total_token_count: Some(500_010),
            cached_content_token_count: None,
        };
        let res_50 = to_claude_usage(&usage_50, true, 1_000_000);
        // 50% * 0.6 = 30% of 195k = 58,500
        assert!(res_50.input_tokens > 55_000 && res_50.input_tokens < 62_000);

        // 测试 70% 负载 (700k) - 应该显示 ~50%
        let usage_70 = UsageMetadata {
            prompt_token_count: Some(700_000),
            candidates_token_count: Some(10),
            total_token_count: Some(700_010),
            cached_content_token_count: None,
        };
        let res_70 = to_claude_usage(&usage_70, true, 1_000_000);
        // 50% of 195k = 97,500
        assert!(res_70.input_tokens > 90_000 && res_70.input_tokens < 105_000);

        // 测试 85% 负载 (850k) - 应该显示 ~70%
        let usage_85 = UsageMetadata {
            prompt_token_count: Some(850_000),
            candidates_token_count: Some(10),
            total_token_count: Some(850_010),
            cached_content_token_count: None,
        };
        let res_85 = to_claude_usage(&usage_85, true, 1_000_000);
        // 70% of 195k = 136,500
        assert!(res_85.input_tokens > 130_000 && res_85.input_tokens < 145_000);

        // 测试 100% 负载 (1M) - 应该显示 ~97%
        let usage_100 = UsageMetadata {
            prompt_token_count: Some(1_000_000),
            candidates_token_count: Some(10),
            total_token_count: Some(1_000_010),
            cached_content_token_count: None,
        };
        let res_100 = to_claude_usage(&usage_100, true, 1_000_000);
        // 97% of 195k = 189,150
        assert!(res_100.input_tokens > 185_000 && res_100.input_tokens <= 190_000);
    }
}