// Copyright (C) 2024 Huawei Device Co., Ltd.
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use std::collections::HashMap;
use std::sync::Arc;

use ylong_http_client::Headers;
use ylong_runtime::net::UnixDatagram;
use ylong_runtime::sync::mpsc::{unbounded_channel, UnboundedSender};
use ylong_runtime::sync::oneshot;

use crate::service::client::{Client, ClientEvent, MessageType};
use crate::task::notify::{NotifyData, SubscribeType, WaitingCause};
use crate::task::reason::Reason;
use crate::config::Version;

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

    // Constants for testing
    const TEST_PID: u64 = 12345;
    const TEST_TID: u32 = 42;

    // @tc.name: ut_client_message_type_variants
    // @tc.desc: Test MessageType enum variants have correct values
    // @tc.precon: MessageType enum is defined
    // @tc.step: 1. Check each variant's discriminant value
    // @tc.expect: Values match expected constants
    // @tc.type: FUNC
    // @tc.require: issue#ICODTG
    // @tc.level: Level 0
    #[test]
    fn ut_client_message_type_variants_001() {
        assert_eq!(MessageType::HttpResponse as u16, 0);
        assert_eq!(MessageType::NotifyData as u16, 1);
        assert_eq!(MessageType::Faults as u16, 2);
        assert_eq!(MessageType::Waiting as u16, 3);
    }

    // @tc.name: ut_client_event_variants
    // @tc.desc: Test ClientEvent enum variants can be constructed
    // @tc.precon: ClientEvent enum is defined
    // @tc.step: 1. Create each variant of ClientEvent
    // @tc.expect: All variants can be instantiated
    // @tc.type: FUNC
    // @tc.require: issue#ICODTG
    // @tc.level: Level 0
    #[test]
    fn ut_client_event_variants_001() {
        let (tx, _rx) = oneshot::channel();
        let headers = Headers::new();

        let _ = ClientEvent::OpenChannel(TEST_PID, tx.clone());
        let _ = ClientEvent::Subscribe(TEST_TID, TEST_PID, 1000, 2000, tx.clone());
        let _ = ClientEvent::Unsubscribe(TEST_TID, tx.clone());
        let _ = ClientEvent::TaskFinished(TEST_TID);
        let _ = ClientEvent::Terminate(TEST_PID, tx.clone());
        let _ = ClientEvent::SendResponse(TEST_TID, "HTTP/1.1".to_string(), 200, "OK".to_string(), headers);
        let _ = ClientEvent::SendNotifyData(SubscribeType::Progress, create_test_notify_data());
        let _ = ClientEvent::SendFaults(TEST_TID, SubscribeType::Complete, Reason::Success);
        let _ = ClientEvent::SendWaitNotify(TEST_TID, WaitingCause::NetworkUnavailable);
        let _ = ClientEvent::Shutdown;
    }

    // @tc.name: ut_client_constructor_socket_creation
    // @tc.desc: Test UnixDatagram socket creation in Client constructor
    // @tc.precon: Unix socket support is available
    // @tc.step: 1. Call Client::constructor
    //           2. Verify socket pair creation
    // @tc.expect: Returns Some with valid sender and socket
    // @tc.type: FUNC
    // @tc.require: issue#ICODTG
    // @tc.level: Level 1
    #[test]
    fn ut_client_constructor_socket_creation_001() {
        let result = Client::constructor(TEST_PID);
        assert!(result.is_some());
        let (sender, socket) = result.unwrap();

        // Verify sender works
        assert!(sender.send(ClientEvent::TaskFinished(TEST_TID)).is_ok());

        // Verify socket is valid
        assert!(Arc::strong_count(&socket) >= 1);
    }

    // @tc.name: ut_client_run_shutdown_handling
    // @tc.desc: Test Client shutdown event handling
    // @tc.precon: Client is constructed and running
    // @tc.step: 1. Create Client
    //           2. Send shutdown event
    //           3. Verify graceful shutdown
    // @tc.expect: Client terminates gracefully
    // @tc.type: FUNC
    // @tc.require: issue#ICODTG
    // @tc.level: Level 1
    #[ylong_runtime::test]
    async fn ut_client_run_shutdown_handling_001() {
        let (sender, _receiver) = unbounded_channel::<ClientEvent>();
        let (server_sock, client_sock) = UnixDatagram::pair().unwrap();

        let client = Client {
            pid: TEST_PID,
            message_id: 1,
            server_sock_fd: server_sock,
            client_sock_fd: Arc::new(client_sock),
            rx: _receiver,
        };

        // Test would need to be more sophisticated for async testing
        // For now, we verify the structure can be created
        assert_eq!(client.pid, TEST_PID);
        assert_eq!(client.message_id, 1);
    }

    // Message format tests
    mod message_format_tests {
        use super::*;

        // @tc.name: ut_client_message_format_magic_number
        // @tc.desc: Test magic number is correctly placed in messages
        // @tc.precon: Message creation functions are available
        // @tc.step: 1. Create a test message
        //           2. Verify magic number at start
        // @tc.expect: Magic number 0x43434646 is first 4 bytes
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 1
        #[test]
        fn ut_client_message_format_magic_number_001() {
            let magic = 0x43434646u32.to_le_bytes();
            assert_eq!(magic, [0x46, 0x46, 0x43, 0x43]);
        }

        // @tc.name: ut_client_message_format_length_field
        // @tc.desc: Test length field positioning in messages
        // @tc.precon: Message structure is defined
        // @tc.step: 1. Create test message
        //           2. Verify length field at position 10
        // @tc.expect: Length field correctly positioned
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 1
        #[test]
        fn ut_client_message_format_length_field_001() {
            const POSITION: u32 = 10;
            assert_eq!(POSITION, 10);
        }

        // @tc.name: ut_client_message_format_headers_max_size
        // @tc.desc: Test maximum headers size constraint
        // @tc.precon: HEADERS_MAX_SIZE is defined
        // @tc.step: 1. Check HEADERS_MAX_SIZE value
        //           2. Verify it's 8KB
        // @tc.expect: Max size is 8192 bytes
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 1
        #[test]
        fn ut_client_message_format_headers_max_size_001() {
            assert_eq!(super::HEADERS_MAX_SIZE, 8 * 1024);
        }
    }

    // Protocol compliance tests
    mod protocol_tests {
        use super::*;

        // @tc.name: ut_client_protocol_response_format
        // @tc.desc: Test HTTP response message format compliance
        // @tc.precon: Client can create response messages
        // @tc.step: 1. Create test response data
        //           2. Verify message structure
        // @tc.expect: Message follows protocol specification
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 1
        #[test]
        fn ut_client_protocol_response_format_001() {
            let mut message = Vec::<u8>::new();

            // Magic number
            message.extend_from_slice(&0x43434646u32.to_le_bytes());

            // Message ID
            message.extend_from_slice(&1u32.to_le_bytes());

            // Message type (HTTP Response)
            message.extend_from_slice(&(MessageType::HttpResponse as u16).to_le_bytes());

            // Message body size (placeholder)
            message.extend_from_slice(&0u16.to_le_bytes());

            // Task ID
            message.extend_from_slice(&TEST_TID.to_le_bytes());

            // HTTP version
            message.extend_from_slice(b"HTTP/1.1\0");

            // Status code
            message.extend_from_slice(&200u32.to_le_bytes());

            // Reason phrase
            message.extend_from_slice(b"OK\0");

            // Headers (empty for this test)

            // Update length field
            let size = message.len() as u16;
            let size_bytes = size.to_le_bytes();
            message[10] = size_bytes[0];
            message[11] = size_bytes[1];

            assert!(message.len() > 20); // Basic sanity check
        }

        // @tc.name: ut_client_protocol_notify_data_format
        // @tc.desc: Test notify data message format compliance
        // @tc.precon: Client can create notify data messages
        // @tc.step: 1. Create test notify data
        //           2. Verify message structure
        // @tc.expect: Message follows protocol specification
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 1
        #[test]
        fn ut_client_protocol_notify_data_format_001() {
            let notify_data = create_test_notify_data();
            let mut message = Vec::<u8>::new();

            // Magic number
            message.extend_from_slice(&0x43434646u32.to_le_bytes());

            // Message ID
            message.extend_from_slice(&1u32.to_le_bytes());

            // Message type (Notify Data)
            message.extend_from_slice(&(MessageType::NotifyData as u16).to_le_bytes());

            // Message body size (placeholder)
            message.extend_from_slice(&0u16.to_le_bytes());

            // Subscribe type
            message.extend_from_slice(&(SubscribeType::Progress as u32).to_le_bytes());

            // Task ID
            message.extend_from_slice(&notify_data.task_id.to_le_bytes());

            // State
            message.extend_from_slice(&(0u32).to_le_bytes()); // Placeholder state

            // Index
            message.extend_from_slice(&0u32.to_le_bytes());

            // Processed bytes
            message.extend_from_slice(&0u64.to_le_bytes());

            // Total processed
            message.extend_from_slice(&0u64.to_le_bytes());

            // Sizes length
            message.extend_from_slice(&0u32.to_le_bytes());

            // Extras count
            message.extend_from_slice(&0u32.to_le_bytes());

            // Action
            message.extend_from_slice(&(0u32).to_le_bytes());

            // Version
            message.extend_from_slice(&(Version::API9 as u32).to_le_bytes());

            // File status count
            message.extend_from_slice(&0u32.to_le_bytes());

            // Update length field
            let size = message.len() as u16;
            let size_bytes = size.to_le_bytes();
            message[10] = size_bytes[0];
            message[11] = size_bytes[1];

            assert!(message.len() > 40); // Basic sanity check
        }
    }

    // Error handling tests
    mod error_handling_tests {
        use super::*;

        // @tc.name: ut_client_error_socket_creation_failure
        // @tc.desc: Test handling of UnixDatagram creation failure
        // @tc.precon: System resource limits reached
        // @tc.step: 1. Attempt to create many sockets
        //           2. Verify graceful handling
        // @tc.expect: Constructor returns None when resources exhausted
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 3
        #[test]
        fn ut_client_error_socket_creation_failure_001() {
            // This test is platform-dependent and may not be reliable
            // In a real scenario, we'd use mocking or resource limits
            let result = Client::constructor(TEST_PID);

            // On most systems, this should succeed for a single client
            assert!(result.is_some());
        }

        // @tc.name: ut_client_error_invalid_task_id
        // @tc.desc: Test handling of invalid task IDs
        // @tc.precon: Client is running
        // @tc.step: 1. Send events with edge case task IDs
        //           2. Verify no crashes
        // @tc.expect: System handles gracefully
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 2
        #[test]
        fn ut_client_error_invalid_task_id_001() {
            let (sender, receiver) = unbounded_channel::<ClientEvent>();

            // Test with zero task ID
            let _ = sender.send(ClientEvent::TaskFinished(0));

            // Test with maximum u32 task ID
            let _ = sender.send(ClientEvent::TaskFinished(u32::MAX));

            // Verify no panics
            drop(receiver);
        }

        // @tc.name: ut_client_error_empty_headers
        // @tc.desc: Test handling of empty headers in response
        // @tc.precon: Client can send responses
        // @tc.step: 1. Create response with empty headers
        //           2. Verify message creation
        // @tc.expect: Message created successfully with empty headers
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 1
        #[test]
        fn ut_client_error_empty_headers_001() {
            let empty_headers = Headers::new();
            let mut response = Vec::<u8>::new();

            response.extend_from_slice(&0x43434646u32.to_le_bytes());
            response.extend_from_slice(&1u32.to_le_bytes());
            response.extend_from_slice(&(MessageType::HttpResponse as u16).to_le_bytes());
            response.extend_from_slice(&0u16.to_le_bytes()); // body size
            response.extend_from_slice(&TEST_TID.to_le_bytes());
            response.extend_from_slice(b"HTTP/1.1\0");
            response.extend_from_slice(&200u32.to_le_bytes());
            response.extend_from_slice(b"OK\0");

            // Empty headers section

            let size = response.len() as u16;
            let size_bytes = size.to_le_bytes();
            response[10] = size_bytes[0];
            response[11] = size_bytes[1];

            assert!(response.len() > 20);
        }

        // @tc.name: ut_client_error_oversized_headers
        // @tc.desc: Test handling of oversized headers
        // @tc.precon: Headers exceed HEADERS_MAX_SIZE
        // @tc.step: 1. Create headers larger than 8KB
        //           2. Verify truncation
        // @tc.expect: Headers are truncated to max size
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 2
        #[test]
        fn ut_client_error_oversized_headers_001() {
            let mut headers = Headers::new();

            // Create oversized headers
            let large_value = "x".repeat(9000);
            headers.insert("X-Large-Header".to_string(), vec![large_value]);

            let mut response = Vec::<u8>::new();
            response.extend_from_slice(&0x43434646u32.to_le_bytes());
            response.extend_from_slice(&1u32.to_le_bytes());
            response.extend_from_slice(&(MessageType::HttpResponse as u16).to_le_bytes());
            response.extend_from_slice(&0u16.to_le_bytes());
            response.extend_from_slice(&TEST_TID.to_le_bytes());
            response.extend_from_slice(b"HTTP/1.1\0");
            response.extend_from_slice(&200u32.to_le_bytes());
            response.extend_from_slice(b"OK\0");

            // Add headers (should be truncated)
            let mut buf_size = 0;
            for (k, v) in &headers {
                buf_size += k.as_bytes().len() + v.iter().map(|f| f.len()).sum::<usize>();
                if buf_size > super::HEADERS_MAX_SIZE as usize {
                    break;
                }

                response.extend_from_slice(k.as_bytes());
                response.push(b':');
                for (i, sub_value) in v.iter().enumerate() {
                    if i != 0 {
                        response.push(b',');
                    }
                    response.extend_from_slice(sub_value.as_bytes());
                }
                response.push(b'\n');
            }

            let mut size = response.len() as u16;
            if size > super::HEADERS_MAX_SIZE {
                response.truncate(super::HEADERS_MAX_SIZE as usize);
                size = super::HEADERS_MAX_SIZE;
            }

            let size_bytes = size.to_le_bytes();
            response[10] = size_bytes[0];
            response[11] = size_bytes[1];

            assert!(response.len() <= super::HEADERS_MAX_SIZE as usize);
        }
    }

    // Edge case tests
    mod edge_case_tests {
        use super::*;

        // @tc.name: ut_client_edge_case_zero_values
        // @tc.desc: Test handling of all zero values
        // @tc.precon: Client is initialized
        // @tc.step: 1. Send events with all zero values
        //           2. Verify message creation
        // @tc.expect: System handles zero values correctly
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 2
        #[test]
        fn ut_client_edge_case_zero_values_001() {
            let notify_data = NotifyData {
                task_id: 0,
                progress: Default::default(),
                action: Reason::Success,
                version: Version::API9,
                each_file_status: vec![],
            };

            let mut message = Vec::<u8>::new();
            message.extend_from_slice(&0x43434646u32.to_le_bytes());
            message.extend_from_slice(&0u32.to_le_bytes()); // message_id
            message.extend_from_slice(&(MessageType::NotifyData as u16).to_le_bytes());
            message.extend_from_slice(&0u16.to_le_bytes());
            message.extend_from_slice(&(SubscribeType::Progress as u32).to_le_bytes());
            message.extend_from_slice(&0u32.to_le_bytes()); // task_id
            message.extend_from_slice(&0u32.to_le_bytes()); // state
            message.extend_from_slice(&0u32.to_le_bytes()); // index
            message.extend_from_slice(&0u64.to_le_bytes()); // processed
            message.extend_from_slice(&0u64.to_le_bytes()); // total
            message.extend_from_slice(&0u32.to_le_bytes()); // sizes len
            message.extend_from_slice(&0u32.to_le_bytes()); // extras count
            message.extend_from_slice(&(Reason::Success as u32).to_le_bytes());
            message.extend_from_slice(&(Version::API9 as u32).to_le_bytes());
            message.extend_from_slice(&0u32.to_le_bytes()); // file status count

            let size = message.len() as u16;
            let size_bytes = size.to_le_bytes();
            message[10] = size_bytes[0];
            message[11] = size_bytes[1];

            assert!(message.len() > 30);
        }

        // @tc.name: ut_client_edge_case_max_values
        // @tc.desc: Test handling of maximum values
        // @tc.precon: Client is initialized
        // @tc.step: 1. Send events with maximum values
        //           2. Verify message creation
        // @tc.expect: System handles max values correctly
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 2
        #[test]
        fn ut_client_edge_case_max_values_001() {
            let max_u32 = u32::MAX;
            let max_u64 = u64::MAX;

            // Test with max values where appropriate
            let mut message = Vec::<u8>::new();
            message.extend_from_slice(&0x43434646u32.to_le_bytes());
            message.extend_from_slice(&max_u32.to_le_bytes()); // message_id
            message.extend_from_slice(&(MessageType::NotifyData as u16).to_le_bytes());
            message.extend_from_slice(&0u16.to_le_bytes());
            message.extend_from_slice(&(SubscribeType::Progress as u32).to_le_bytes());
            message.extend_from_slice(&max_u32.to_le_bytes()); // task_id

            let size = message.len() as u16;
            let size_bytes = size.to_le_bytes();
            message[10] = size_bytes[0];
            message[11] = size_bytes[1];

            // Just verify the message was created without panic
            assert!(message.len() > 20);
        }

        // @tc.name: ut_client_edge_case_unicode_strings
        // @tc.desc: Test handling of Unicode strings in headers
        // @tc.precon: Unicode support is available
        // @tc.step: 1. Create headers with Unicode content
        //           2. Verify message creation
        // @tc.expect: Unicode strings are handled correctly
        // @tc.type: FUNC
        // @tc.require: issue#ICODTG
        // @tc.level: Level 2
        #[test]
        fn ut_client_edge_case_unicode_strings_001() {
            let mut headers = Headers::new();
            headers.insert("Content-Type".to_string(), vec!["text/plain; charset=utf-8".to_string()]);
            headers.insert("X-Unicode-Header".to_string(), vec!["测试".to_string()]);

            let mut response = Vec::<u8>::new();
            response.extend_from_slice(&0x43434646u32.to_le_bytes());
            response.extend_from_slice(&1u32.to_le_bytes());
            response.extend_from_slice(&(MessageType::HttpResponse as u16).to_le_bytes());
            response.extend_from_slice(&0u16.to_le_bytes());
            response.extend_from_slice(&TEST_TID.to_le_bytes());
            response.extend_from_slice(b"HTTP/1.1\0");
            response.extend_from_slice(&200u32.to_le_bytes());
            response.extend_from_slice(b"OK\0");

            // Add Unicode headers
            for (k, v) in &headers {
                response.extend_from_slice(k.as_bytes());
                response.push(b':');
                for (i, sub_value) in v.iter().enumerate() {
                    if i != 0 {
                        response.push(b',');
                    }
                    response.extend_from_slice(sub_value.as_bytes());
                }
                response.push(b'\n');
            }

            let size = response.len() as u16;
            let size_bytes = size.to_le_bytes();
            response[10] = size_bytes[0];
            response[11] = size_bytes[1];

            assert!(response.len() > 50);
        }
    }

    // Helper function to create test NotifyData
    fn create_test_notify_data() -> NotifyData {
        NotifyData {
            task_id: TEST_TID,
            progress: Default::default(),
            action: Reason::Success,
            version: Version::API9,
            each_file_status: vec![],
        }
    }
}