"""
Behavioral tests for API client patterns.

These tests verify the logic of API client patterns like request building,
response parsing, header management, authentication, and error handling
without making actual HTTP requests.
"""

import base64
import hashlib
import hmac
import json
import time
import urllib.parse
from dataclasses import dataclass


class TestRequestBuilding:
    """Tests for building HTTP requests."""

    def test_build_get_request(self):
        """Test building a GET request."""

        def build_request(method, url, params=None):
            request = {"method": method, "url": url}
            if params:
                query = urllib.parse.urlencode(params)
                request["url"] = f"{url}?{query}"
            return request

        request = build_request(
            "GET", "https://api.example.com/users", {"page": 1}
        )
        assert request["method"] == "GET"
        assert "page=1" in request["url"]

    def test_build_post_request_with_json_body(self):
        """Test building a POST request with JSON body."""

        def build_request(
            method, url, body=None, content_type="application/json"
        ):
            request = {"method": method, "url": url, "headers": {}}
            if body:
                request["body"] = json.dumps(body)
                request["headers"]["Content-Type"] = content_type
            return request

        request = build_request(
            "POST",
            "https://api.example.com/users",
            {"name": "John", "email": "j@x.com"},
        )
        assert request["method"] == "POST"
        assert request["headers"]["Content-Type"] == "application/json"
        body = json.loads(request["body"])
        assert body["name"] == "John"

    def test_build_request_with_path_params(self):
        """Test building request with path parameters."""

        def build_url(template, path_params):
            url = template
            for key, value in path_params.items():
                url = url.replace(f"{{{key}}}", str(value))
            return url

        url = build_url(
            "https://api.example.com/users/{user_id}/posts/{post_id}",
            {"user_id": 123, "post_id": 456},
        )
        assert url == "https://api.example.com/users/123/posts/456"

    def test_encode_query_params(self):
        """Test encoding query parameters."""

        def encode_params(params):
            return urllib.parse.urlencode(params, doseq=True)

        # Simple params
        assert encode_params({"a": 1, "b": 2}) == "a=1&b=2"

        # Special characters
        encoded = encode_params({"query": "hello world"})
        assert "hello+world" in encoded or "hello%20world" in encoded

        # List values
        encoded = encode_params({"tags": ["a", "b", "c"]})
        assert "tags=a" in encoded and "tags=b" in encoded

    def test_build_multipart_form_data(self):
        """Test building multipart form data."""

        def build_multipart(fields, boundary="----boundary"):
            parts = []
            for name, value in fields.items():
                part = f'--{boundary}\r\nContent-Disposition: form-data; name="{name}"\r\n\r\n{value}\r\n'
                parts.append(part)
            parts.append(f"--{boundary}--\r\n")
            return "".join(parts)

        result = build_multipart({"name": "John", "age": "30"})
        assert 'name="name"' in result
        assert "John" in result
        assert 'name="age"' in result
        assert "30" in result


class TestResponseParsing:
    """Tests for parsing HTTP responses."""

    def test_parse_json_response(self):
        """Test parsing JSON response."""

        def parse_response(body, content_type):
            if "application/json" in content_type:
                return json.loads(body)
            return body

        result = parse_response('{"id": 1, "name": "John"}', "application/json")
        assert result["id"] == 1
        assert result["name"] == "John"

    def test_parse_paginated_response(self):
        """Test parsing paginated response."""

        @dataclass
        class PaginatedResponse:
            data: list
            page: int
            total_pages: int
            total_items: int
            has_next: bool
            has_prev: bool

        def parse_paginated(response):
            return PaginatedResponse(
                data=response.get("data", []),
                page=response.get("page", 1),
                total_pages=response.get("total_pages", 1),
                total_items=response.get("total", 0),
                has_next=response.get("page", 1)
                < response.get("total_pages", 1),
                has_prev=response.get("page", 1) > 1,
            )

        result = parse_paginated(
            {"data": [1, 2, 3], "page": 2, "total_pages": 5, "total": 50}
        )
        assert result.data == [1, 2, 3]
        assert result.page == 2
        assert result.has_next is True
        assert result.has_prev is True

    def test_extract_links_from_response(self):
        """Test extracting links from response headers."""

        def parse_link_header(header):
            links = {}
            if not header:
                return links
            for part in header.split(","):
                match = part.strip()
                if "<" in match and ">" in match:
                    url = match[match.index("<") + 1 : match.index(">")]
                    if 'rel="' in match:
                        rel_start = match.index('rel="') + 5
                        rel_end = match.index('"', rel_start)
                        rel = match[rel_start:rel_end]
                        links[rel] = url
            return links

        header = '<https://api.example.com/users?page=2>; rel="next", <https://api.example.com/users?page=10>; rel="last"'
        links = parse_link_header(header)
        assert links["next"] == "https://api.example.com/users?page=2"
        assert links["last"] == "https://api.example.com/users?page=10"

    def test_handle_empty_response(self):
        """Test handling empty response."""

        def parse_response(body, status_code):
            if status_code == 204 or not body:
                return None
            return json.loads(body)

        assert parse_response("", 204) is None
        assert parse_response("", 200) is None
        assert parse_response('{"ok": true}', 200) == {"ok": True}

    def test_parse_error_response(self):
        """Test parsing error response."""

        @dataclass
        class APIError:
            status: int
            code: str
            message: str
            details: dict

        def parse_error(body, status_code):
            try:
                data = json.loads(body)
                return APIError(
                    status=status_code,
                    code=data.get("error", {}).get("code", "unknown"),
                    message=data.get("error", {}).get(
                        "message", "Unknown error"
                    ),
                    details=data.get("error", {}).get("details", {}),
                )
            except json.JSONDecodeError:
                return APIError(
                    status=status_code,
                    code="parse_error",
                    message=body,
                    details={},
                )

        error = parse_error(
            '{"error": {"code": "not_found", "message": "User not found"}}', 404
        )
        assert error.status == 404
        assert error.code == "not_found"
        assert error.message == "User not found"


class TestHeaderManagement:
    """Tests for HTTP header management."""

    def test_set_default_headers(self):
        """Test setting default headers."""

        def get_default_headers(api_key=None, user_agent="MyClient/1.0"):
            headers = {
                "Accept": "application/json",
                "User-Agent": user_agent,
            }
            if api_key:
                headers["Authorization"] = f"Bearer {api_key}"
            return headers

        headers = get_default_headers("secret123")
        assert headers["Accept"] == "application/json"
        assert headers["Authorization"] == "Bearer secret123"
        assert headers["User-Agent"] == "MyClient/1.0"

    def test_merge_headers(self):
        """Test merging headers with precedence."""

        def merge_headers(default_headers, custom_headers):
            result = default_headers.copy()
            result.update(custom_headers)
            return result

        default = {"Accept": "application/json", "User-Agent": "Client/1.0"}
        custom = {"Accept": "text/html", "X-Custom": "value"}
        merged = merge_headers(default, custom)
        assert merged["Accept"] == "text/html"  # Custom overrides
        assert merged["User-Agent"] == "Client/1.0"  # Default preserved
        assert merged["X-Custom"] == "value"  # Custom added

    def test_parse_response_headers(self):
        """Test parsing response headers."""

        def get_rate_limit_info(headers):
            return {
                "limit": int(headers.get("X-RateLimit-Limit", 0)),
                "remaining": int(headers.get("X-RateLimit-Remaining", 0)),
                "reset": int(headers.get("X-RateLimit-Reset", 0)),
            }

        headers = {
            "X-RateLimit-Limit": "100",
            "X-RateLimit-Remaining": "95",
            "X-RateLimit-Reset": "1609459200",
        }
        info = get_rate_limit_info(headers)
        assert info["limit"] == 100
        assert info["remaining"] == 95

    def test_content_type_detection(self):
        """Test content type detection."""

        def get_content_type(body):
            if isinstance(body, dict) or isinstance(body, list):
                return "application/json"
            if isinstance(body, str) and body.startswith("<?xml"):
                return "application/xml"
            if isinstance(body, bytes):
                return "application/octet-stream"
            return "text/plain"

        assert get_content_type({"key": "value"}) == "application/json"
        assert get_content_type('<?xml version="1.0"?>') == "application/xml"
        assert get_content_type(b"binary") == "application/octet-stream"
        assert get_content_type("hello") == "text/plain"

    def test_accept_header_negotiation(self):
        """Test Accept header content negotiation."""

        def negotiate_content_type(accept_header, available_types):
            # Parse Accept header and return best match
            if not accept_header or accept_header == "*/*":
                return available_types[0] if available_types else None

            preferences = []
            for part in accept_header.split(","):
                part = part.strip()
                quality = 1.0
                if ";q=" in part:
                    type_part, q_part = part.split(";q=")
                    quality = float(q_part)
                    part = type_part.strip()
                preferences.append((part, quality))

            preferences.sort(key=lambda x: x[1], reverse=True)

            for pref_type, _ in preferences:
                if pref_type in available_types:
                    return pref_type
            return None

        available = ["application/json", "application/xml", "text/html"]
        assert (
            negotiate_content_type("application/json", available)
            == "application/json"
        )
        assert (
            negotiate_content_type(
                "application/xml;q=0.9, application/json;q=1.0", available
            )
            == "application/json"
        )


class TestAuthentication:
    """Tests for API authentication patterns."""

    def test_basic_auth_header(self):
        """Test Basic authentication header generation."""

        def basic_auth_header(username, password):
            credentials = f"{username}:{password}"
            encoded = base64.b64encode(credentials.encode()).decode()
            return f"Basic {encoded}"

        header = basic_auth_header("user", "pass")
        assert header.startswith("Basic ")
        decoded = base64.b64decode(header.split(" ")[1]).decode()
        assert decoded == "user:pass"

    def test_bearer_token_header(self):
        """Test Bearer token header generation."""

        def bearer_auth_header(token):
            return f"Bearer {token}"

        header = bearer_auth_header("eyJhbGciOiJIUzI1NiIs...")
        assert header == "Bearer eyJhbGciOiJIUzI1NiIs..."

    def test_api_key_auth(self):
        """Test API key authentication."""

        def api_key_auth(api_key, location="header", param_name="X-API-Key"):
            if location == "header":
                return {"headers": {param_name: api_key}}
            if location == "query":
                return {"params": {param_name: api_key}}
            return {}

        header_auth = api_key_auth("secret123", "header")
        assert header_auth["headers"]["X-API-Key"] == "secret123"

        query_auth = api_key_auth("secret123", "query", "api_key")
        assert query_auth["params"]["api_key"] == "secret123"

    def test_hmac_signature(self):
        """Test HMAC signature generation."""

        def generate_signature(secret, message):
            key = secret.encode()
            msg = message.encode()
            return hmac.new(key, msg, hashlib.sha256).hexdigest()

        sig1 = generate_signature(
            "secret", "message"
        )  # DevSkim: ignore DS126858 - uses SHA-256
        sig2 = generate_signature(
            "secret", "message"
        )  # DevSkim: ignore DS126858 - uses SHA-256
        sig3 = generate_signature("other", "message")
        assert sig1 == sig2  # Same input = same signature
        assert sig1 != sig3  # Different secret = different signature
        assert len(sig1) == 64  # SHA256 hex = 64 chars

    def test_oauth_token_refresh_check(self):
        """Test OAuth token refresh check."""

        def should_refresh_token(expires_at, buffer_seconds=300):
            if not expires_at:
                return False
            now = time.time()
            return now >= (expires_at - buffer_seconds)

        # Token expires in 10 seconds - should refresh
        assert should_refresh_token(time.time() + 10) is True

        # Token expires in 10 minutes - no need to refresh
        assert should_refresh_token(time.time() + 600) is False

        # Token already expired - should refresh
        assert should_refresh_token(time.time() - 10) is True


class TestRetryLogic:
    """Tests for API retry logic."""

    def test_should_retry_status_code(self):
        """Test determining if status code should trigger retry."""

        def should_retry(status_code, retry_codes=None):
            if retry_codes is None:
                retry_codes = {408, 429, 500, 502, 503, 504}
            return status_code in retry_codes

        assert should_retry(429) is True  # Rate limited
        assert should_retry(503) is True  # Service unavailable
        assert should_retry(404) is False  # Not found - no retry
        assert should_retry(400) is False  # Bad request - no retry

    def test_calculate_retry_delay(self):
        """Test calculating retry delay with backoff."""

        def calculate_delay(
            attempt, base_delay=1.0, max_delay=60.0, multiplier=2.0
        ):
            delay = base_delay * (multiplier ** (attempt - 1))
            return min(delay, max_delay)

        assert calculate_delay(1) == 1.0
        assert calculate_delay(2) == 2.0
        assert calculate_delay(3) == 4.0
        assert calculate_delay(10) == 60.0  # Capped at max

    def test_respect_retry_after_header(self):
        """Test respecting Retry-After header."""

        def get_retry_delay(headers, default_delay=1.0):
            retry_after = headers.get("Retry-After")
            if retry_after:
                try:
                    return float(retry_after)
                except ValueError:
                    # Could be HTTP date format, use default
                    pass
            return default_delay

        assert get_retry_delay({"Retry-After": "30"}) == 30.0
        assert get_retry_delay({}) == 1.0
        assert get_retry_delay({"Retry-After": "invalid"}) == 1.0

    def test_max_retries_exceeded(self):
        """Test max retries check."""

        def can_retry(attempt, max_retries=3):
            return attempt < max_retries

        assert can_retry(1, max_retries=3) is True
        assert can_retry(2, max_retries=3) is True
        assert can_retry(3, max_retries=3) is False
        assert can_retry(4, max_retries=3) is False

    def test_idempotent_method_check(self):
        """Test checking if method is idempotent for retry."""

        def is_idempotent(method):
            return method.upper() in {"GET", "HEAD", "PUT", "DELETE", "OPTIONS"}

        assert is_idempotent("GET") is True
        assert is_idempotent("PUT") is True
        assert is_idempotent("POST") is False  # Not idempotent by default


class TestURLBuilding:
    """Tests for URL building and manipulation."""

    def test_join_url_parts(self):
        """Test joining URL parts."""

        def join_url(base, *parts):
            url = base.rstrip("/")
            for part in parts:
                url = f"{url}/{part.strip('/')}"
            return url

        assert (
            join_url("https://api.example.com", "users", "123")
            == "https://api.example.com/users/123"
        )
        assert (
            join_url("https://api.example.com/", "/users/", "/123/")
            == "https://api.example.com/users/123"
        )

    def test_add_query_params(self):
        """Test adding query parameters to URL."""

        def add_params(url, params):
            if not params:
                return url
            query = urllib.parse.urlencode(params)
            separator = "&" if "?" in url else "?"
            return f"{url}{separator}{query}"

        assert (
            add_params("https://api.example.com/users", {"page": 1})
            == "https://api.example.com/users?page=1"
        )
        assert (
            add_params(
                "https://api.example.com/users?status=active", {"page": 1}
            )
            == "https://api.example.com/users?status=active&page=1"
        )

    def test_parse_url_components(self):
        """Test parsing URL components."""

        def parse_url(url):
            parsed = urllib.parse.urlparse(url)
            return {
                "scheme": parsed.scheme,
                "host": parsed.netloc,
                "path": parsed.path,
                "query": dict(urllib.parse.parse_qsl(parsed.query)),
            }

        result = parse_url("https://api.example.com/users?page=1&limit=10")
        assert result["scheme"] == "https"
        assert result["host"] == "api.example.com"
        assert result["path"] == "/users"
        assert result["query"]["page"] == "1"
        assert result["query"]["limit"] == "10"

    def test_url_template_expansion(self):
        """Test URL template expansion."""

        def expand_template(template, variables):
            result = template
            for key, value in variables.items():
                result = result.replace(
                    f"{{{key}}}", urllib.parse.quote(str(value))
                )
            return result

        template = "https://api.example.com/users/{id}/posts/{post_id}"
        result = expand_template(template, {"id": 123, "post_id": 456})
        assert result == "https://api.example.com/users/123/posts/456"

    def test_encode_special_characters(self):
        """Test encoding special characters in URL."""

        def safe_encode(value):
            return urllib.parse.quote(str(value), safe="")

        assert safe_encode("hello world") == "hello%20world"
        assert safe_encode("a+b") == "a%2Bb"
        assert safe_encode("a/b") == "a%2Fb"


class TestRequestValidation:
    """Tests for request validation."""

    def test_validate_required_params(self):
        """Test validating required parameters."""

        def validate_required(params, required_fields):
            missing = [
                f
                for f in required_fields
                if f not in params or params[f] is None
            ]
            return missing

        missing = validate_required({"name": "John"}, ["name", "email"])
        assert missing == ["email"]

        missing = validate_required(
            {"name": "John", "email": "j@x.com"}, ["name", "email"]
        )
        assert missing == []

    def test_validate_param_types(self):
        """Test validating parameter types."""

        def validate_types(params, type_spec):
            errors = []
            for field, expected_type in type_spec.items():
                if field in params:
                    value = params[field]
                    if not isinstance(value, expected_type):
                        errors.append(
                            f"{field}: expected {expected_type.__name__}"
                        )
            return errors

        errors = validate_types(
            {"name": "John", "age": "thirty"}, {"name": str, "age": int}
        )
        assert len(errors) == 1
        assert "age" in errors[0]

    def test_validate_param_range(self):
        """Test validating parameter value range."""

        def validate_range(value, min_val=None, max_val=None):
            if min_val is not None and value < min_val:
                return f"Value must be >= {min_val}"
            if max_val is not None and value > max_val:
                return f"Value must be <= {max_val}"
            return None

        assert validate_range(5, min_val=1, max_val=10) is None
        assert validate_range(0, min_val=1) == "Value must be >= 1"
        assert validate_range(15, max_val=10) == "Value must be <= 10"

    def test_sanitize_request_params(self):
        """Test sanitizing request parameters."""

        def sanitize_params(params, strip_none=True, trim_strings=True):
            result = {}
            for key, value in params.items():
                if strip_none and value is None:
                    continue
                if trim_strings and isinstance(value, str):
                    value = value.strip()
                result[key] = value
            return result

        params = {"name": "  John  ", "email": None, "age": 30}
        sanitized = sanitize_params(params)
        assert sanitized == {"name": "John", "age": 30}

    def test_validate_content_length(self):
        """Test validating content length."""

        def validate_content_length(body, max_size=1024 * 1024):
            if body is None:
                return None
            size = len(body.encode() if isinstance(body, str) else body)
            if size > max_size:
                return f"Content too large: {size} > {max_size}"
            return None

        assert validate_content_length("small body") is None
        assert validate_content_length("x" * 2_000_000) is not None


class TestResponseCaching:
    """Tests for response caching logic."""

    def test_is_cacheable_response(self):
        """Test determining if response is cacheable."""

        def is_cacheable(status_code, method, cache_control=None):
            if method not in {"GET", "HEAD"}:
                return False
            if status_code not in {200, 203, 204, 206, 300, 301, 404, 410}:
                return False
            if cache_control:
                if "no-store" in cache_control or "no-cache" in cache_control:
                    return False
            return True

        assert is_cacheable(200, "GET") is True
        assert is_cacheable(200, "POST") is False
        assert is_cacheable(500, "GET") is False
        assert is_cacheable(200, "GET", "no-store") is False

    def test_parse_cache_control_header(self):
        """Test parsing Cache-Control header."""

        def parse_cache_control(header):
            directives = {}
            for part in header.split(","):
                part = part.strip()
                if "=" in part:
                    key, value = part.split("=", 1)
                    directives[key.strip()] = value.strip()
                else:
                    directives[part] = True
            return directives

        result = parse_cache_control("max-age=3600, public, no-transform")
        assert result["max-age"] == "3600"
        assert result["public"] is True
        assert result["no-transform"] is True

    def test_calculate_cache_expiry(self):
        """Test calculating cache expiry time."""

        def calculate_expiry(headers, default_ttl=300):
            cache_control = headers.get("Cache-Control", "")
            if "max-age=" in cache_control:
                for part in cache_control.split(","):
                    if "max-age=" in part:
                        max_age = int(part.split("=")[1].strip())
                        return time.time() + max_age
            return time.time() + default_ttl

        headers = {"Cache-Control": "max-age=3600"}
        expiry = calculate_expiry(headers)
        assert expiry > time.time() + 3500

    def test_generate_cache_key(self):
        """Test generating cache key."""

        def generate_cache_key(method, url, params=None, vary_headers=None):
            parts = [method.upper(), url]
            if params:
                parts.append(json.dumps(params, sort_keys=True))
            if vary_headers:
                parts.append(json.dumps(vary_headers, sort_keys=True))
            key_string = "|".join(parts)
            return hashlib.sha256(key_string.encode()).hexdigest()

        key1 = generate_cache_key("GET", "/api/users", {"page": 1})
        key2 = generate_cache_key("GET", "/api/users", {"page": 1})
        key3 = generate_cache_key(
            "GET", "/api/users", {"page": 2}
        )  # DevSkim: ignore DS126858
        assert key1 == key2  # Same request = same key
        assert key1 != key3  # Different params = different key

    def test_should_revalidate(self):
        """Test checking if cache should be revalidated."""

        def should_revalidate(cached_at, max_age, stale_while_revalidate=0):
            age = time.time() - cached_at
            if age <= max_age:
                return False  # Still fresh
            if age <= max_age + stale_while_revalidate:
                return True  # Stale but can serve while revalidating
            return True  # Must revalidate

        now = time.time()
        # Fresh - no revalidation needed
        assert should_revalidate(now - 100, 300) is False
        # Expired - revalidation needed
        assert should_revalidate(now - 400, 300) is True


class TestTimeoutHandling:
    """Tests for timeout handling."""

    def test_calculate_timeout(self):
        """Test calculating request timeout."""

        def calculate_timeout(operation, default_timeout=30):
            timeouts = {
                "read": 30,
                "write": 60,
                "upload": 300,
                "download": 300,
            }
            return timeouts.get(operation, default_timeout)

        assert calculate_timeout("read") == 30
        assert calculate_timeout("upload") == 300
        assert calculate_timeout("unknown") == 30

    def test_adjust_timeout_for_content_size(self):
        """Test adjusting timeout based on content size."""

        def adjust_timeout(base_timeout, content_size, bytes_per_second=50000):
            if content_size <= 0:
                return base_timeout
            estimated_time = content_size / bytes_per_second
            return max(base_timeout, estimated_time * 1.5)

        # Small content - use base timeout
        assert adjust_timeout(30, 1000) == 30

        # Large content - increase timeout
        timeout = adjust_timeout(30, 5_000_000)
        assert timeout > 30

    def test_timeout_budget(self):
        """Test timeout budget tracking."""

        @dataclass
        class TimeoutBudget:
            total: float
            started_at: float
            spent: float = 0.0

            def remaining(self):
                elapsed = time.time() - self.started_at
                return max(0, self.total - elapsed - self.spent)

            def spend(self, amount):
                self.spent += amount

        budget = TimeoutBudget(total=30.0, started_at=time.time())
        assert budget.remaining() > 25  # Should have most time remaining
        budget.spend(10.0)
        assert budget.remaining() < 20


class TestWebhookHandling:
    """Tests for webhook handling patterns."""

    def test_verify_webhook_signature(self):
        """Test verifying webhook signature."""

        def verify_signature(payload, signature, secret, algorithm="sha256"):
            if algorithm == "sha256":
                expected = hmac.new(
                    secret.encode(), payload.encode(), hashlib.sha256
                ).hexdigest()
            else:
                return False
            return hmac.compare_digest(signature, expected)

        payload = '{"event": "test"}'
        secret = "webhook_secret"
        valid_sig = hmac.new(
            secret.encode(), payload.encode(), hashlib.sha256
        ).hexdigest()

        assert verify_signature(payload, valid_sig, secret) is True
        assert verify_signature(payload, "invalid", secret) is False

    def test_parse_webhook_event(self):
        """Test parsing webhook event."""

        @dataclass
        class WebhookEvent:
            event_type: str
            timestamp: str
            payload: dict

        def parse_webhook(body):
            data = json.loads(body)
            return WebhookEvent(
                event_type=data.get("type", "unknown"),
                timestamp=data.get("timestamp", ""),
                payload=data.get("data", {}),
            )

        body = '{"type": "user.created", "timestamp": "2024-01-01T00:00:00Z", "data": {"id": 123}}'
        event = parse_webhook(body)
        assert event.event_type == "user.created"
        assert event.payload["id"] == 123

    def test_deduplicate_webhook(self):
        """Test webhook deduplication."""

        class WebhookDeduplicator:
            def __init__(self):
                self.processed_ids = set()

            def is_duplicate(self, event_id):
                if event_id in self.processed_ids:
                    return True
                self.processed_ids.add(event_id)
                return False

        dedup = WebhookDeduplicator()
        assert dedup.is_duplicate("event_1") is False
        assert dedup.is_duplicate("event_1") is True  # Duplicate
        assert dedup.is_duplicate("event_2") is False


class TestBatchRequests:
    """Tests for batch request patterns."""

    def test_chunk_requests(self):
        """Test chunking requests into batches."""

        def chunk_requests(items, batch_size=100):
            return [
                items[i : i + batch_size]
                for i in range(0, len(items), batch_size)
            ]

        items = list(range(250))
        batches = chunk_requests(items, 100)
        assert len(batches) == 3
        assert len(batches[0]) == 100
        assert len(batches[1]) == 100
        assert len(batches[2]) == 50

    def test_build_batch_request(self):
        """Test building a batch request."""

        def build_batch_request(requests):
            return {
                "batch": [
                    {"id": str(i), "method": r["method"], "url": r["url"]}
                    for i, r in enumerate(requests)
                ]
            }

        requests = [
            {"method": "GET", "url": "/users/1"},
            {"method": "GET", "url": "/users/2"},
        ]
        batch = build_batch_request(requests)
        assert len(batch["batch"]) == 2
        assert batch["batch"][0]["id"] == "0"

    def test_parse_batch_response(self):
        """Test parsing batch response."""

        def parse_batch_response(response):
            results = {}
            for item in response.get("responses", []):
                results[item["id"]] = {
                    "status": item["status"],
                    "body": item.get("body"),
                }
            return results

        response = {
            "responses": [
                {"id": "0", "status": 200, "body": {"name": "John"}},
                {"id": "1", "status": 404, "body": None},
            ]
        }
        results = parse_batch_response(response)
        assert results["0"]["status"] == 200
        assert results["1"]["status"] == 404

    def test_aggregate_batch_errors(self):
        """Test aggregating batch errors."""

        def aggregate_errors(results):
            errors = []
            for request_id, result in results.items():
                if result["status"] >= 400:
                    errors.append(
                        {
                            "request_id": request_id,
                            "status": result["status"],
                            "message": result.get("body", {}).get(
                                "error", "Unknown"
                            ),
                        }
                    )
            return errors

        results = {
            "0": {"status": 200, "body": {}},
            "1": {"status": 404, "body": {"error": "Not found"}},
            "2": {"status": 500, "body": {"error": "Server error"}},
        }
        errors = aggregate_errors(results)
        assert len(errors) == 2
        assert errors[0]["status"] == 404
