#!/usr/bin/env python3
"""
Scan router.go for Gin radix tree param name conflicts.
Gin requires all routes at the same URL position to use the same param name.

Strategy: Build a prefix tree, find all positions where multiple param names are used.
"""
import re

with open('/home/yanghao05/Workspace/gochat/internal/router/router.go') as f:
    lines = f.readlines()

# Track Group nesting to build full paths
group_stack = []  # list of (var_name, prefix_path)
routes = []

# Parse the file line by line
for i, line in enumerate(lines):
    stripped = line.strip()
    if stripped.startswith('//') or not stripped:
        continue
    
    # Detect Group definition: varName := parent.Group("/path")
    gmatch = re.match(r'(\w+)\s*:?=\s*(\w+)\.Group\("([^"]+)"\)', stripped)
    if gmatch:
        var_name = gmatch.group(1)
        parent = gmatch.group(2)
        path = gmatch.group(3)
        # Find parent prefix
        parent_prefix = ''
        for name, prefix in group_stack:
            if name == parent:
                parent_prefix = prefix
                break
        full_prefix = parent_prefix + path
        group_stack.append((var_name, full_prefix))
        continue
    
    # Detect route registration: var.Method("/path", handler)
    for method in ['GET', 'POST', 'PUT', 'PATCH', 'DELETE']:
        pattern = rf'^(\w+)\.{method}\("([^"]+)"\s*,'
        rmatch = re.match(pattern, stripped)
        if rmatch:
            var_name = rmatch.group(1)
            path = rmatch.group(2)
            # Find prefix for this group variable
            prefix = ''
            for name, p in group_stack:
                if name == var_name:
                    prefix = p
                    break
            full_path = prefix + path
            routes.append((method, full_path, i+1))
            break

# Now build a radix-tree-like structure to find conflicts
# At each path segment position, track all param names seen
tree = {}  # key: tuple of segments up to a position -> set of param names at that position

for method, path, linenum in routes:
    segments = [s for s in path.split('/') if s]  # skip empty segments
    for pos, seg in enumerate(segments):
        if seg.startswith(':'):
            param_name = seg[1:]
            prefix_key = '/'.join(segments[:pos])
            if prefix_key not in tree:
                tree[prefix_key] = {}
            if pos not in tree[prefix_key]:
                tree[prefix_key][pos] = {}
            if param_name not in tree[prefix_key][pos]:
                tree[prefix_key][pos][param_name] = []
            tree[prefix_key][pos][param_name].append((method, path, linenum))

# Find conflicts
print("=== Gin路由参数名冲突检测 ===\n")
conflicts_found = 0
for prefix, positions in sorted(tree.items()):
    for pos, names_dict in positions.items():
        if len(names_dict) > 1:
            names = sorted(names_dict.keys())
            conflicts_found += 1
            print(f"冲突 #{conflicts_found}: 前缀 '{prefix}' 位置 {pos}")
            print(f"  参数名: {names}")
            for name, refs in names_dict.items():
                print(f"  :{name} 的使用:")
                for method, path, linenum in refs[:3]:
                    print(f"    Line {linenum}: {method} {path}")
                if len(refs) > 3:
                    print(f"    ... (还有 {len(refs)-3} 条)")
            print()

print(f"总计冲突: {conflicts_found}")