// 代码优化
// 提供性能优化建议和热点分析

use std::collections::HashMap;

/// 优化建议类型
#[derive(Debug, Clone, PartialEq)]
pub enum OptimizationType {
    CachingImprovement,    // 缓存改进
    AlgorithmOptimization, // 算法优化
    ConcurrencyEnhancement,// 并发增强
    MemoryOptimization,    // 内存优化
    IOOptimization,        // I/O优化
}

/// 优化建议
#[derive(Debug, Clone)]
pub struct OptimizationSuggestion {
    pub optimization_type: OptimizationType,
    pub description: String,
    pub priority: u8, // 1-10, 10最高
    pub estimated_improvement: f64, // 预期改进百分比
}

/// 热点分析结果
#[derive(Debug, Clone)]
pub struct HotspotAnalysis {
    pub function_name: String,
    pub execution_count: u64,
    pub total_time_ms: f64,
    pub avg_time_ms: f64,
}

/// 代码优化系统
pub struct CodeOptimizer {
    suggestions: Vec<OptimizationSuggestion>,
    hotspots: Vec<HotspotAnalysis>,
}

impl CodeOptimizer {
    pub fn new() -> Self {
        Self {
            suggestions: Vec::new(),
            hotspots: Vec::new(),
        }
    }

    /// 分析热点
    pub fn analyze_hotspots(&mut self, function_name: String, execution_count: u64, total_time_ms: f64) {
        let hotspot = HotspotAnalysis {
            function_name,
            execution_count,
            total_time_ms,
            avg_time_ms: total_time_ms / execution_count as f64,
        };
        
        self.hotspots.push(hotspot);
    }

    /// 添加优化建议
    pub fn add_suggestion(&mut self, suggestion: OptimizationSuggestion) {
        self.suggestions.push(suggestion);
    }

    /// 生成优化报告
    pub fn generate_optimization_report(&self) -> String {
        let mut report = String::from("=== 代码优化报告 ===\n\n");
        
        // 热点分析
        report.push_str("热点函数分析:\n");
        let mut sorted_hotspots = self.hotspots.clone();
        sorted_hotspots.sort_by(|a, b| b.total_time_ms.partial_cmp(&a.total_time_ms).unwrap());
        
        for (i, hotspot) in sorted_hotspots.iter().take(5).enumerate() {
            report.push_str(&format!("{}. {} - 执行{}次, 总耗时{:.2}ms, 平均{:.2}ms\n",
                i + 1,
                hotspot.function_name,
                hotspot.execution_count,
                hotspot.total_time_ms,
                hotspot.avg_time_ms
            ));
        }
        
        // 优化建议
        report.push_str("\n优化建议:\n");
        let mut sorted_suggestions = self.suggestions.clone();
        sorted_suggestions.sort_by(|a, b| b.priority.cmp(&a.priority));
        
        for (i, suggestion) in sorted_suggestions.iter().enumerate() {
            report.push_str(&format!("{}. [优先级{}] {:?}: {}\n   预期改进: {:.1}%\n",
                i + 1,
                suggestion.priority,
                suggestion.optimization_type,
                suggestion.description,
                suggestion.estimated_improvement
            ));
        }
        
        report
    }

    /// 获取热点列表
    pub fn get_hotspots(&self) -> &[HotspotAnalysis] {
        &self.hotspots
    }

    /// 获取优化建议
    pub fn get_suggestions(&self) -> &[OptimizationSuggestion] {
        &self.suggestions
    }
}

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

    #[test]
    fn test_hotspot_analysis() {
        let mut optimizer = CodeOptimizer::new();
        
        optimizer.analyze_hotspots("validate_transaction".to_string(), 1000, 500.0);
        optimizer.analyze_hotspots("execute_contract".to_string(), 500, 1000.0);
        
        let hotspots = optimizer.get_hotspots();
        assert_eq!(hotspots.len(), 2);
        assert_eq!(hotspots[0].avg_time_ms, 0.5);
    }

    #[test]
    fn test_optimization_suggestions() {
        let mut optimizer = CodeOptimizer::new();
        
        optimizer.add_suggestion(OptimizationSuggestion {
            optimization_type: OptimizationType::CachingImprovement,
            description: "添加LRU缓存".to_string(),
            priority: 8,
            estimated_improvement: 30.0,
        });
        
        let suggestions = optimizer.get_suggestions();
        assert_eq!(suggestions.len(), 1);
        assert_eq!(suggestions[0].priority, 8);
    }

    #[test]
    fn test_generate_report() {
        let mut optimizer = CodeOptimizer::new();
        
        optimizer.analyze_hotspots("test_function".to_string(), 100, 100.0);
        optimizer.add_suggestion(OptimizationSuggestion {
            optimization_type: OptimizationType::AlgorithmOptimization,
            description: "使用更高效的算法".to_string(),
            priority: 9,
            estimated_improvement: 50.0,
        });
        
        let report = optimizer.generate_optimization_report();
        assert!(report.contains("代码优化报告"));
        assert!(report.contains("test_function"));
    }
}