#!/usr/bin/python3

import sys
import re

c_keywords = set([
    'auto', 'break', 'case', 'char', 'const', 'continue', 'default', 'do',
    'double', 'else', 'enum', 'extern', 'float', 'for', 'goto', 'if',
    'int', 'long', 'register', 'return', 'short', 'signed', 'sizeof', 'static',
    'struct', 'switch', 'typedef', 'union', 'unsigned', 'void', 'volatile', 'while',
    '_Alignas', '_Alignof', '_Atomic', '_Bool', '_Complex', '_Generic', '_Imaginary',
    '_Noreturn', '_Static_assert', '_Thread_local'
])

def read_filelist(filename='filelist.txt'):
    with open(filename, 'r') as f:
        return [line.strip() for line in f if line.strip()]

def load_files(files):
    contents = {}
    for f in files:
        with open(f, 'r') as fd:
            contents[f] = fd.read().splitlines()
    return contents

def extract_functions_and_structs(lines):
    functions = []
    structs = []
    enums = []
    i = 0
    n = len(lines)
    multi_comment = False
    extern_c_level = 0  # Track extern "C" nesting level
    pre_lines = []

    def skip_multi_comment(line):
        nonlocal multi_comment
        if multi_comment:
            if '*/' in line:
                multi_comment = False
            return True
        if '/*' in line and '*/' not in line:
            multi_comment = True
            return True
        return False

    while i < n:
        line = lines[i]
        stripped = line.strip()

        if skip_multi_comment(line):
            pre_lines.append(line)
            i += 1
            continue

        if stripped.startswith('//') or not stripped or stripped.startswith('#'):
            pre_lines.append(line)
            i += 1
            continue

        # Skip closing braces
        if stripped.startswith('}'):
            pre_lines = []
            i += 1
            continue

        # Check for struct/enum/union declarations
        is_typedef = stripped.startswith('typedef ')
        is_struct = stripped.startswith('struct ')
        is_enum = stripped.startswith('enum ')
        is_union = stripped.startswith('union ')
        is_typedef_struct = stripped.startswith('typedef struct')
        is_typedef_enum = stripped.startswith('typedef enum')
        is_typedef_union = stripped.startswith('typedef union')

        if is_typedef_struct or is_typedef_enum or is_typedef_union or is_struct or is_enum or is_union:
            decl_lines = [line]
            start_line = i
            already_processed = False  # Flag to skip brace counting if already processed
            i += 1

            # Collect declaration until we find { or ;
            while i < n:
                line = lines[i]
                stripped_cont = line.strip()

                if skip_multi_comment(line):
                    decl_lines.append(line)
                    i += 1
                    continue

                if stripped_cont.startswith('//') or stripped_cont.startswith('#'):
                    break

                decl_lines.append(line)

                # Check if we hit the opening brace
                if '{' in stripped_cont:
                    break

                # Check if it's a forward declaration or end of typedef
                # Forward declaration: "typedef enum name;" - no { before
                # End of typedef: "} name;" - has { before and } in current line
                if stripped_cont.endswith(';'):
                    has_brace = any('{' in l for l in decl_lines)
                    if not has_brace:
                        # Forward declaration, skip
                        pre_lines = []
                        i += 1
                        break
                    elif '}' in stripped_cont:
                        # End of typedef (e.g., "} debug_level_t;")
                        # Don't need to count braces, already have the complete declaration
                        end_line = i
                        decl_text = ' '.join([l.strip() for l in decl_lines])
                        
                        # Extract name
                        close_brace = decl_text.rfind('}')
                        semi = decl_text.find(';', close_brace)
                        if semi > close_brace:
                            name = decl_text[close_brace + 1:semi].strip()
                        else:
                            name = decl_text[close_brace + 1:].strip()
                        
                        if is_typedef_enum:
                            enums.append({'name': name, 'pre': pre_lines[:], 'start': start_line, 'end': end_line, 'line_count': end_line - start_line + 1})
                        elif is_typedef_struct or is_typedef_union:
                            structs.append({'name': name, 'pre': pre_lines[:], 'start': start_line, 'end': end_line, 'line_count': end_line - start_line + 1})
                        
                        pre_lines = []
                        i += 1
                        already_processed = True
                        break

                i += 1

            # Skip brace counting if we already processed this typedef (found "} name;")
            if already_processed:
                pre_lines = []
                continue

            if i >= n or not any('{' in l for l in decl_lines):
                pre_lines = []
                continue

            # Now we're inside the struct/enum/union body, find the closing }
            brace_level = 1
            while i < n and brace_level > 0:
                i += 1
                if i >= n:
                    break
                line = lines[i]
                decl_lines.append(line)
                stripped_line = line.strip()

                if skip_multi_comment(line):
                    continue

                # Skip preprocessor directives when counting braces
                # Check for # after stripping leading whitespace (handles indented #define)
                if stripped_line.startswith('#'):
                    continue
                
                # Skip extern "C" { blocks (C++ linkage)
                if 'extern "C"' in stripped_line or stripped_line.startswith('extern'):
                    if '{' in stripped_line:
                        extern_c_level += 1
                    continue
                
                # Skip closing brace of extern "C" block
                if extern_c_level > 0 and stripped_line == '}':
                    extern_c_level -= 1
                    continue
                
                # If we're inside extern "C", skip counting braces
                if extern_c_level > 0:
                    continue
                
                # Skip do { ... } while(0) patterns in macros
                if stripped_line.startswith('do {'):
                    continue
                if stripped_line.startswith('}') and 'while(0)' in stripped_line:
                    continue

                brace_level += line.count('{') - line.count('}')

            # Check if there's a name after } (for typedef) or if it's a simple struct
            end_line = i
            decl_text = ' '.join([l.strip() for l in decl_lines])

            # Extract name and determine type
            if is_typedef_struct or is_typedef_enum or is_typedef_union:
                # Name is after the closing brace and before ;
                # Format: typedef struct { ... } name;
                close_brace = decl_text.rfind('}')
                semi = decl_text.find(';', close_brace)
                if semi > close_brace:
                    name = decl_text[close_brace + 1:semi].strip()
                else:
                    name = decl_text[close_brace + 1:].strip()

                if is_typedef_enum:
                    item_type = 'enum'
                    enums.append({'name': name, 'pre': pre_lines[:], 'start': start_line, 'end': end_line, 'line_count': end_line - start_line + 1})
                else:
                    item_type = 'struct'
                    structs.append({'name': name, 'pre': pre_lines[:], 'start': start_line, 'end': end_line, 'line_count': end_line - start_line + 1})
            else:
                # Simple struct/enum/union name { ... };
                # Name is between keyword and {
                keyword = 'struct' if is_struct else ('enum' if is_enum else 'union')
                keyword_pos = decl_text.find(keyword)
                brace_pos = decl_text.find('{', keyword_pos)
                name = decl_text[keyword_pos + len(keyword):brace_pos].strip()

                # Skip anonymous structs (no name) - they are local variables, not declarations
                if not name:
                    pre_lines = []
                    continue

                if is_enum:
                    enums.append({'name': name, 'pre': pre_lines[:], 'start': start_line, 'end': end_line, 'line_count': end_line - start_line + 1})
                else:
                    structs.append({'name': name, 'pre': pre_lines[:], 'start': start_line, 'end': end_line, 'line_count': end_line - start_line + 1})

            pre_lines = []
            continue

        # Handle function declarations
        if '(' in stripped and not stripped.startswith('typedef'):
            decl_lines = [line]
            start_line = i
            i += 1
            paren_level = stripped.count('(') - stripped.count(')')

            while i < n and paren_level > 0:
                line = lines[i]
                stripped_cont = line.strip()

                if skip_multi_comment(line):
                    decl_lines.append(line)
                    i += 1
                    continue

                if stripped_cont.startswith('//') or stripped_cont.startswith('#'):
                    break

                decl_lines.append(line)
                paren_level += stripped_cont.count('(') - stripped_cont.count(')')
                
                # Check if we closed all parens and found opening brace on same line
                if paren_level == 0 and '{' in stripped_cont:
                    break
                    
                i += 1

            # Check if current or next line starts with {
            has_brace = False
            if i < n:
                current_line = lines[i].strip()
                if '{' in current_line:
                    has_brace = True
                elif i + 1 < n and lines[i + 1].strip().startswith('{'):
                    i += 1
                    has_brace = True
                    decl_lines.append(lines[i])
                    i += 1
            
            if has_brace:
                decl_lines.append(lines[i])
                i += 1

                # Find function end
                brace_level = 1
                while i < n and brace_level > 0:
                    line = lines[i]
                    decl_lines.append(line)

                    if skip_multi_comment(line):
                        i += 1
                        continue

                    brace_level += line.count('{') - line.count('}')
                    i += 1

                end_line = i - 1

                # Parse function signature
                decl_text = ' '.join([l.strip() for l in decl_lines])
                paren_start = decl_text.find('(')
                paren_end = decl_text.rfind(')', 0, decl_text.find('{'))

                if paren_start > 0 and paren_end > paren_start:
                    args = decl_text[paren_start + 1:paren_end].strip()
                    before_paren = decl_text[:paren_start].strip()
                    parts = before_paren.rsplit(maxsplit=1)

                    if len(parts) == 2:
                        ret_type = parts[0]
                        name = parts[1]
                    else:
                        ret_type = 'void'
                        name = parts[0] if parts else 'unknown'

                    if name not in c_keywords and name.isidentifier():
                        functions.append({
                            'type': 'function',
                            'name': name,
                            'args': args,
                            'ret': ret_type,
                            'pre': pre_lines[:],
                            'start': start_line,
                            'end': end_line,
                            'line_count': end_line - start_line + 1
                        })

            pre_lines = []
            continue

        # Not a declaration we care about
        pre_lines = []
        i += 1

    return functions, structs, enums

if __name__ == "__main__":
    files = read_filelist()
    contents = load_files(files)
    project_functions = {}
    project_structs = {}
    project_enums = {}
    for f, lines in contents.items():
        funcs, strs, enums = extract_functions_and_structs(lines)
        project_functions[f] = funcs
        project_structs[f] = strs
        project_enums[f] = enums
    if len(sys.argv) < 2:
        print("Usage: python script.py toc | func <file> <funcname> | struct <file> <structname> | enum <file> <enumname>")
        sys.exit(1)
    cmd = sys.argv[1]
    if cmd == 'toc':
        for f in files:
            print(f"File: {f}")
            funcs = project_functions.get(f, [])
            strs = project_structs.get(f, [])
            enums = project_enums.get(f, [])
            if funcs:
                for func in funcs:
                    print(f"Function: {func['ret']} {func['name']}({func['args']}) - {func['line_count']} lines")
            if strs:
                for s in strs:
                    print(f"Struct: {s['name']} - {s['line_count']} lines")
            if enums:
                for e in enums:
                    print(f"Enum: {e['name']} - {e['line_count']} lines")
    elif cmd == 'func':
        if len(sys.argv) < 4:
            print("Usage: python script.py func <file> <funcname>")
            sys.exit(1)
        file = sys.argv[2]
        funcname = sys.argv[3]
        found = False
        if file in project_functions:
            for func in project_functions[file]:
                if func['name'] == funcname:
                    lines = contents[file]
                    pre = func['pre']
                    body = lines[func['start']:func['end'] + 1]
                    print('\n'.join(pre + body))
                    found = True
                    break
        if not found:
            print("Function not found")
    elif cmd == 'struct':
        if len(sys.argv) < 4:
            print("Usage: python script.py struct <file> <structname>")
            sys.exit(1)
        file = sys.argv[2]
        structname = sys.argv[3]
        found = False
        if file in project_structs:
            for strct in project_structs[file]:
                if strct['name'] == structname:
                    lines = contents[file]
                    pre = strct['pre']
                    body = lines[strct['start']:strct['end'] + 1]
                    print('\n'.join(pre + body))
                    found = True
                    break
        if not found:
            print("Struct not found")
    elif cmd == 'enum':
        if len(sys.argv) < 4:
            print("Usage: python script.py enum <file> <enumname>")
            sys.exit(1)
        file = sys.argv[2]
        enumname = sys.argv[3]
        found = False
        if file in project_enums:
            for enm in project_enums[file]:
                if enm['name'] == enumname:
                    lines = contents[file]
                    pre = enm['pre']
                    body = lines[enm['start']:enm['end'] + 1]
                    print('\n'.join(pre + body))
                    found = True
                    break
        if not found:
            print("Enum not found")
    else:
        print("Unknown command")