#!/usr/bin/env python3
"""Phase 1: Baseline Comparison - 7 methods compared fairly"""
import sys, os, json
sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))

from src.gatekeeper import ContextGatekeeper

TOPICS = ['Redis', 'asyncio', 'PostgreSQL', 'Git']

def estimate_tokens(text):
    if not text: return 0
    chinese = sum(1 for c in text if '\u4e00' <= c <= '\u9fff')
    english = len([w for w in text.split() if w.isascii()])
    return int(chinese * 0.4 + english * 1.3 + len(text) * 0.05)

def measure_prompt_tokens(selected, query):
    ctx = ""
    for item in selected:
        ctx += f"用户: {item['user']}\n助手: {item['assistant']}\n\n"
    context_tok = estimate_tokens(ctx)
    query_tok = estimate_tokens(query)
    fmt_overhead = int(context_tok * 0.08)
    return context_tok + fmt_overhead + query_tok

def evaluate_contamination(selected, target):
    text = " ".join(item['user'] + item['assistant'] for item in selected)
    found = [t for t in TOPICS if t.lower() in text.lower() and t.lower() != target.lower()]
    return len(found) > 0, found

# 100轮对话
redis_qa = [
    ("Redis 分布式锁和 RedLock 算法有什么区别？", "RedLock是..."),
    ("Redis 集群环境下怎么做分布式锁？", "集群下..."),
    ("Redis 惰性删除和定期删除有什么区别？", "惰性删除..."),
    ("Redis 的过期 key 对 RDB 快照有什么影响？", "过期key..."),
    ("Redis 主从复制断线后如何增量同步？", "PSYNC..."),
]
asyncio_qa = [
    ("asyncio.Task 的 cancel 方法怎么工作的？", "cancel..."),
    ("asyncio.gather 和 asyncio.wait 的返回结果有什么区别？", "gather..."),
    ("asyncio 的事件循环怎么启动和停止？", "事件循环..."),
    ("asyncio.sleep 和 time.sleep 的区别是什么？", "sleep..."),
    ("asyncio 的 Future 对象怎么获取结果？", "Future..."),
]
pg_qa = [
    ("PostgreSQL 的 MVCC 机制是怎么保证读不阻塞写的？", "MVCC..."),
    ("PostgreSQL 的 VACUUM 为什么要定期运行？", "VACUUM..."),
    ("PostgreSQL 的 EXPLAIN ANALYZE 怎么看执行计划？", "EXPLAIN..."),
    ("PostgreSQL B-tree 索引和 Hash 索引的区别是什么？", "B-tree..."),
    ("PostgreSQL 的 TOAST 机制是什么？", "TOAST..."),
]
git_qa = [
    ("Git 的 rebase 和 merge 的区别是什么？", "rebase..."),
    ("Git reset 的 --soft、--mixed、--hard 有什么区别？", "reset..."),
    ("Git stash 暂存区和工作目录的区别是什么？", "stash..."),
    ("Git 的 bisect 怎么用来快速定位 bug？", "bisect..."),
    ("Git 的 reflog 怎么用来恢复误删的提交？", "reflog..."),
]

# 测试序列
TEST_SEQ = [
    ("问PG", "EXPLAIN ANALYZE 怎么看执行计划？", "PostgreSQL"),
    ("问Git", "Git 的 rebase 和 merge 有什么区别？", "Git"),
    ("问Redis", "Redis 惰性删除和定期删除有什么区别？", "Redis"),
    ("问asyncio", "asyncio.Task 的 cancel 方法怎么工作的？", "asyncio"),
    ("再问Git", "Git 的 reset 和 revert 的应用场景有什么区别？", "Git"),
]

def build_full_conv():
    g = ContextGatekeeper(token_budget=4000)
    for i in range(5):
        g.add_turn(redis_qa[i][0], redis_qa[i][1])
        g.add_turn(asyncio_qa[i][0], asyncio_qa[i][1])
        g.add_turn(pg_qa[i][0], pg_qa[i][1])
        g.add_turn(git_qa[i][0], git_qa[i][1])
    return g

def build_conv_list():
    conv = []
    for i in range(5):
        conv.append({'user': redis_qa[i][0], 'assistant': redis_qa[i][1]})
        conv.append({'user': asyncio_qa[i][0], 'assistant': asyncio_qa[i][1]})
        conv.append({'user': pg_qa[i][0], 'assistant': pg_qa[i][1]})
        conv.append({'user': git_qa[i][0], 'assistant': git_qa[i][1]})
    return conv

def last_n_select(conv, n, query):
    return conv[-n:]

def bm25_select(conv, top_k, query):
    qw = set(query.lower().split())
    scored = []
    for i, t in enumerate(conv):
        txt = (t['user'] + ' ' + t['assistant']).lower()
        sc = sum(1 for w in qw if w in txt)
        recency = (i + 1) / len(conv)
        scored.append((i, t, sc + recency * 0.2))
    scored.sort(key=lambda x: x[2], reverse=True)
    return [s[1] for s in scored[:top_k]]

def main():
    gate = build_full_conv()
    conv = build_conv_list()

    methods = {
        'Last-3': lambda q: last_n_select(conv, 3, q),
        'Last-5': lambda q: last_n_select(conv, 5, q),
        'Last-10': lambda q: last_n_select(conv, 10, q),
        'BM25-5': lambda q: bm25_select(conv, 5, q),
        'Full CGK': lambda q: gate.select(q),
    }

    results = {k: [] for k in methods}
    cgk_prompt_tokens_list = []

    print("=" * 70)
    print("Phase 1: Baseline Comparison")
    print("=" * 70)

    for label, query, target in TEST_SEQ:
        # CGK
        sel = gate.select(query)
        pt = measure_prompt_tokens(sel, query)
        cont, _ = evaluate_contamination(sel, target)
        results['Full CGK'].append({'label': label, 'pt': pt, 'cont': cont})
        cgk_prompt_tokens_list.append(pt)

        # Baselines
        for name in ['Last-3', 'Last-5', 'Last-10', 'BM25-5']:
            sel = methods[name](query)
            pt = measure_prompt_tokens(sel, query)
            cont, _ = evaluate_contamination(sel, target)
            results[name].append({'label': label, 'pt': pt, 'cont': cont})

        print(f"\n[{label}] {query[:45]}...")
        for name, data in results.items():
            r = data[-1]
            print(f"  {name:10s}: {r['pt']:6.0f} tokens, 污染={r['cont']}")

    # Summary
    print("\n" + "=" * 70)
    print("Summary (avg over {} queries)".format(len(TEST_SEQ)))
    print("=" * 70)

    for name, data in results.items():
        avg_pt = sum(d['pt'] for d in data) / len(data)
        cont_rate = sum(1 for d in data if d['cont']) / len(data) * 100
        print(f"{name:10s}: avg {avg_pt:6.1f} prompt tokens, 污染率 {cont_rate:5.1f}%")

    # CGK vs baselines
    cgk_avg = sum(cgk_prompt_tokens_list) / len(cgk_prompt_tokens_list)
    print(f"\nFull CGK avg prompt tokens: {cgk_avg:.1f}")

    # Save
    out = {}
    for name, data in results.items():
        out[name] = {'avg_tokens': sum(d['pt'] for d in data)/len(data),
                     'contamination_rate': sum(1 for d in data if d['cont'])/len(data)*100,
                     'raw': data}

    out_path = os.path.join(os.path.dirname(__file__), 'phase1_baseline_results.json')
    with open(out_path, 'w') as f:
        json.dump(out, f, indent=2, ensure_ascii=False)
    print(f"\nSaved to: {out_path}")

if __name__ == '__main__':
    main()