toast-api 0.1.9

use log::{debug, warn, error, info, trace};
use anyhow::{anyhow, Result};
use base64::{engine::general_purpose::STANDARD, Engine as _};
use futures::StreamExt;
use rquest::header::{HeaderMap, HeaderValue};
use rquest::Client;
use rquest_util::Emulation;
use serde::{Deserialize, Serialize};
use serde_json::{json, Value};
use std::fs;
use std::path::Path;
use std::time::{Duration, Instant};
use rand::Rng;
use crate::sha3;


// Constants
const BASE_URL: &str = "https://chat.deepseek.com/api/v0";

// Define the types for thinking and search modes
#[derive(Clone, Copy)]
pub enum ThinkingMode {
    Detailed,
    Simple,
    Disabled,
}

impl ThinkingMode {
    fn as_bool(&self) -> bool {
        !matches!(self, ThinkingMode::Disabled)
    }
}

#[derive(Clone, Copy)]
pub enum SearchMode {
    Enabled,
    Disabled,
}

impl SearchMode {
    fn as_bool(&self) -> bool {
        matches!(self, SearchMode::Enabled)
    }
}

// Session data for DeepSeek API
#[derive(Clone)]
pub struct Session {
    pub auth_token: String,
    pub cookies: serde_json::Value,
}

// Challenge from DeepSeek for proof-of-work
#[derive(Debug, Deserialize, Serialize)]
pub struct PowChallenge {
    pub algorithm: String,
    pub challenge: String,
    pub salt: String,
    pub difficulty: f64,
    pub expire_at: u64,
    pub signature: String,
    pub target_path: String,
}

// Proof-of-Work solver using WebAssembly with fallback
pub struct DeepSeekPOW {}

impl DeepSeekPOW {
    pub fn new() -> Result<Self> {
        debug!("Initializing native SHA3 POW solver");
        Ok(Self {})
    }
    
    fn solve_with_wasm(&self, config: &PowChallenge) -> Result<i64> {
        debug!("Attempting POW solve with WASM implementation");
        use crate::sha3::WasmInstance;
        
        match WasmInstance::new() {
            Ok(mut instance) => {
                let prefix = format!("{}_{}_", config.salt, config.expire_at);
                
                match instance.calculate_hash(&config.challenge, &prefix, config.difficulty) {
                    Ok(Some(nonce)) => {
                        Ok(nonce as i64)
                    }
                    Ok(None) => {
                        Err(anyhow!("WASM did not find solution"))
                    }
                    Err(e) => {
                        Err(anyhow!("WASM error: {}", e))
                    }
                }
            }
            Err(e) => {
                Err(anyhow!("Failed to create WASM instance: {}", e))
            }
        }
    }

        fn solve_with_native(&self, config: &PowChallenge) -> Result<i64> {
        debug!("Solving POW with native SHA3 implementation");
        let challenge_str = &config.challenge;
        let prefix = format!("{}_{}_", config.salt, config.expire_at);
        
        // Use the sha3 module to solve the challenge
        let prefix_bytes = prefix.as_bytes();
        let challenge_bytes = challenge_str.as_bytes();
        
        debug!("Solving with prefix: '{}', challenge: '{}', difficulty: {}", 
               prefix, challenge_str, config.difficulty);
        
        let (success, nonce) = sha3::solve(challenge_bytes, prefix_bytes, config.difficulty);
        if success {
            info!("Native POW solver found solution: nonce = {nonce}");
            Ok(nonce as i64)
        } else {
            Err(anyhow!("Failed to find POW solution within attempt limit"))
        }
    }

    
    pub fn solve_challenge(&self, config: &PowChallenge) -> Result<String> {
        debug!("Processing verification: algorithm={}, difficulty={}", config.algorithm, config.difficulty);
        
        let _solve_start = std::time::Instant::now();
        
        // Try WASM first
        let answer = match self.solve_with_wasm(config) {
            Ok(nonce) => {
                nonce
            }
            Err(_wasm_err) => {
                
                self.solve_with_native(config)?
            }
        };
        
        let result = json!({
            "algorithm": config.algorithm,
            "challenge": config.challenge,
            "salt": config.salt,
            "answer": answer,
            "signature": config.signature,
            "target_path": config.target_path
        });
        
        let encoded = STANDARD.encode(result.to_string());
        debug!("POW response encoded: {encoded}");
        Ok(encoded)
    }
}

/// DeepSeek API client
pub struct DeepSeek {
    http: Client,
    session: Session,
    pow_solver: DeepSeekPOW,
    cookies_refreshed: bool,
    last_request_time: Instant,
    message_counter: i32,
    message_history: Vec<ChatMessage>,
}

#[derive(Clone, Debug, Serialize)]
struct ChatMessage {
    role: String,
    content: String,
}

impl DeepSeek {
    /// Create a new DeepSeek client
    pub fn new(session: Session) -> Result<Self> {
        info!("Creating DeepSeek client");
        
                let http = Client::builder()
            .emulation(Emulation::Chrome131)
            .timeout(Duration::from_secs(600))
            .connect_timeout(Duration::from_secs(15))
            .gzip(true)
            .brotli(true)
            .deflate(true)
            .build()?;
            
        let pow_solver = DeepSeekPOW::new()?;
        
        debug!("DeepSeek client initialized successfully");
        Ok(Self {
            http,
            session,
            pow_solver,
            cookies_refreshed: false,
            last_request_time: Instant::now(),
            message_counter: 0,
            message_history: Vec::new(),
        })
    }

    fn default_headers(&self, pow_response: Option<&str>) -> HeaderMap {
        let mut headers = HeaderMap::new();
        headers.insert("accept", HeaderValue::from_static("*/*"));
        headers.insert(
            "accept-encoding", 
            HeaderValue::from_static("gzip, deflate, br, zstd")
        );
        headers.insert(
            "accept-language", 
            HeaderValue::from_static("en-US,en;q=0.9")
        );
        headers.insert(
            "authorization", 
            HeaderValue::from_str(&format!("Bearer {}", self.session.auth_token)).unwrap()
        );
        headers.insert(
            "cache-control", 
            HeaderValue::from_static("no-cache")
        );
        headers.insert(
            "content-type", 
            HeaderValue::from_static("application/json")
        );
        headers.insert(
            "dnt", 
            HeaderValue::from_static("1")
        );
        headers.insert(
            "origin", 
            HeaderValue::from_static("https://chat.deepseek.com")
        );
        headers.insert(
            "pragma", 
            HeaderValue::from_static("no-cache")
        );
        headers.insert(
            "priority", 
            HeaderValue::from_static("u=1, i")
        );
        headers.insert(
            "referer", 
            HeaderValue::from_static("https://chat.deepseek.com/")
        );
        headers.insert(
            "sec-ch-ua", 
            HeaderValue::from_static("\"Google Chrome\";v=\"131\", \"Chromium\";v=\"131\", \"Not_A Brand\";v=\"24\"")
        );
        headers.insert(
            "sec-ch-ua-mobile", 
            HeaderValue::from_static("?0")
        );
        headers.insert(
            "sec-ch-ua-platform", 
            HeaderValue::from_static("\"Windows\"")
        );
        headers.insert(
            "sec-fetch-dest", 
            HeaderValue::from_static("empty")
        );
        headers.insert(
            "sec-fetch-mode", 
            HeaderValue::from_static("cors")
        );
        headers.insert(
            "sec-fetch-site", 
            HeaderValue::from_static("same-origin")
        );
        headers.insert(
            "user-agent", 
            HeaderValue::from_static("Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36")
        );
        headers.insert(
            "x-app-version", 
            HeaderValue::from_static("20241201.0")
        );
        headers.insert(
            "x-client-locale", 
            HeaderValue::from_static("en_US")
        );
        headers.insert(
            "x-client-platform", 
            HeaderValue::from_static("web")
        );
        headers.insert(
            "x-client-version", 
            HeaderValue::from_static("1.0.0")
        );
        
        if let Some(pow_res) = pow_response {
            headers.insert(
                "x-ds-pow-response", 
                HeaderValue::from_str(pow_res).unwrap()
            );
        }
        
        headers
    }
    
    /// Refresh cookies by running the bypass.py script
    async fn refresh_cookies(&mut self) -> Result<()> {
        warn!("Attempting to refresh cookies");
        // Only attempt to refresh once per session to avoid excessive attempts
        if self.cookies_refreshed {
            return Err(anyhow!("Already attempted to refresh cookies once this session"));
        }
        
        // This is where we'd typically run bypass.py
        // For now we just mark as refreshed to avoid repeated attempts
        self.cookies_refreshed = true;
        
        // In a full implementation, we would start the Python server and fetch the cookies
        // For now, return an error suggesting manual cookie retrieval
        Err(anyhow!(
            "Cookie refresh needed. Please run the Python bypass script manually and update the cookie file"
        ))
    }
    
    /// Make a request to the DeepSeek API
    async fn make_request<T: for<'de> Deserialize<'de>>(
        &mut self, 
        method: &str, 
        endpoint: &str, 
        json_data: Value,
        pow_required: bool
    ) -> Result<T> {
        let url = format!("{BASE_URL}{endpoint}");
        debug!("Making {method} request to: {url}");
        let mut retry_count = 0;
        trace!("Request JSON data: {json_data}");
        let max_retries = 2;
        
        while retry_count < max_retries {
            debug!("Request attempt {} of {}", retry_count + 1, max_retries);
            let mut headers = self.default_headers(None);
            
            if pow_required {
                let challenge = self.get_pow_challenge().await?;
                let pow_response = self.pow_solver.solve_challenge(&challenge)?;
                headers = self.default_headers(Some(&pow_response));
            }
            
            let request_builder = match method {
                "GET" => self.http.get(&url),
                "POST" => self.http.post(&url),
                "DELETE" => self.http.delete(&url),
                "PUT" => self.http.put(&url),
                _ => return Err(anyhow!("Unsupported HTTP method: {}", method)),
            };
            
            // Add cookies from session
            let cookies_map = match &self.session.cookies {
                Value::Object(obj) => obj,
                _ => return Err(anyhow!("Invalid cookies format in session")),
            };
            
            let mut cookie_str = String::new();
            for (key, value) in cookies_map {
                if let Value::String(val) = value {
                    if !cookie_str.is_empty() {
                        cookie_str.push_str("; ");
                    }
                    cookie_str.push_str(&format!("{key}={val}"));
                }
            }
            
            if !cookie_str.is_empty() {
                headers.insert("Cookie", HeaderValue::from_str(&cookie_str)?);
                debug!("Added cookies: {} characters", cookie_str.len());
            } else {
                warn!("No cookies available for request");
            }
            
                    // Add human-like delay between requests to avoid detection
        let elapsed = self.last_request_time.elapsed();
        if elapsed < Duration::from_millis(200) {
            let mut rng = rand::thread_rng();
            let delay_ms = rng.gen_range(200..800);
            tokio::time::sleep(Duration::from_millis(delay_ms)).await;
        }
        self.last_request_time = Instant::now();
        
        let response = match request_builder
                .headers(headers)
                .json(&json_data)
                .send()
                .await
            {
                Ok(resp) => resp,
                Err(e) => {
                    error!("Network error on attempt {}: {}", retry_count + 1, e);
                    return Err(anyhow!("Network error: {}", e));
                }
            };
            
            // Check for Cloudflare protection
            let status = response.status();
            let text = response.text().await?;
            debug!("Response received - Status: {}, Content length: {}", status, text.len());
            trace!("Response body preview: {}", &text[..std::cmp::min(200, text.len())]);
            
            if text.contains("<!DOCTYPE html>") && text.contains("Just a moment") {
                debug!("Page verification required on attempt {}", retry_count + 1);
                debug!("Response text snippet: {}", &text[..std::cmp::min(200, text.len())]);
                if retry_count < max_retries - 1 {
                    self.refresh_cookies().await.ok(); // Try to refresh, ignore errors
                    retry_count += 1;
                    continue;
                } else {
                    return Err(anyhow!("Request verification failed"));
                }
            }
            
            // Handle response codes
            match status.as_u16() {
                200 => {
                    debug!("Successful response received, parsing JSON");
                    // Parse JSON response
                    match serde_json::from_str(&text) {
                        Ok(parsed) => return Ok(parsed),
                        Err(e) => {
                            error!("Failed to parse JSON response: {e}");
                            debug!("Response text: {text}");
                            return Err(anyhow!("Failed to parse API response: {}", e));
                        }
                    }
                }
                401 => {
                    error!("Authentication error (401): {text}");
                    return Err(anyhow!("Authentication error: Invalid or expired authentication token"));
                }
                429 => {
                    warn!("Rate limit exceeded (429): {text}"); 
                    return Err(anyhow!("Rate limit exceeded"));
                }
                _ => {
                    warn!("HTTP error {} on attempt {}: {}", status, retry_count + 1, text);
                    if retry_count < max_retries - 1 {
                        retry_count += 1;
                        tokio::time::sleep(Duration::from_secs(1)).await;
                        continue;
                    }
                    error!("API request failed after {max_retries} attempts with status {status}: {text}");
                    return Err(anyhow!("API request failed with status {}: {}", status, text));
                }
            }
        }
        
        Err(anyhow!("Failed to get a valid response after {} attempts", max_retries))
    }
    
    /// Get a proof-of-work challenge from the API
    async fn get_pow_challenge(&mut self) -> Result<PowChallenge> {
        debug!("Requesting verification token");
        let url = format!("{BASE_URL}/chat/create_pow_challenge");
        debug!("POW challenge URL: {url}");
        
        let request_body = json!({"target_path": "/api/v0/chat/completion"}).to_string();
        debug!("POW request body: {request_body}");
        
        let mut headers = self.default_headers(None);
        debug!("Prepared {} headers for POW request", headers.len());
        
        // Add cookies
        let cookies_map = match &self.session.cookies {
            Value::Object(obj) => {
                debug!("Found {} cookie entries for POW request", obj.len());
                obj
            },
            _ => {
                error!("Invalid cookies format in session for POW request");
                return Err(anyhow!("Invalid cookies format in session"));
            }
        };
        
        let mut cookie_str = String::new();
        let mut cookie_count = 0;
        for (key, value) in cookies_map {
            if let Value::String(val) = value {
                if !cookie_str.is_empty() {
                    cookie_str.push_str("; ");
                }
                cookie_str.push_str(&format!("{key}={val}"));
                cookie_count += 1;
            }
        }
        
        if !cookie_str.is_empty() {
            headers.insert("Cookie", HeaderValue::from_str(&cookie_str)?);
            debug!("Added {} cookies to POW request ({} chars)", cookie_count, cookie_str.len());
        } else {
            warn!("No cookies available for POW challenge request");
        }
        
        // Make the request
        debug!("Sending POW challenge HTTP request...");
        let response = match self.http.post(&url)
            .headers(headers)
            .body(request_body)
            .send()
            .await {
                Ok(r) => {
                    debug!("POW challenge request completed, status: {}", r.status());
                    r
                },
                Err(e) => {
                    error!("POW challenge HTTP request failed: {e}");
                    return Err(anyhow!("POW challenge request failed: {}", e));
                }
            };
        
        let status = response.status();
        debug!("POW challenge response status: {status}");
        
        if !status.is_success() {
            let error_text = response.text().await?;
            error!("POW challenge request failed: HTTP {status} - {error_text}");
            return Err(anyhow!(
                "Failed to get challenge: HTTP {} - {}", 
                status,
                error_text
            ));
        }
        
        // Parse the response
        debug!("POW challenge request successful, parsing response...");
        let response_json: Value = match response.json().await {
            Ok(json) => {
                debug!("Successfully parsed POW challenge response JSON");
                trace!("POW challenge response: {json:?}");
                json
            },
            Err(e) => {
                error!("Failed to parse POW challenge response as JSON: {e}");
                return Err(anyhow!("Failed to parse POW response: {}", e));
            }
        };
        
        // Extract the challenge from the response
        match response_json.get("data").and_then(|d| d.get("biz_data")).and_then(|b| b.get("challenge")) {
            Some(challenge) => {
                let challenge_value = challenge.clone();
                debug!("Received POW challenge: {challenge_value:?}");
                match serde_json::from_value::<PowChallenge>(challenge_value) {
                    Ok(c) => Ok(c),
                    Err(e) => {
                        error!("Failed to parse POW challenge: {e}");
                        Err(anyhow!("Failed to parse challenge: {}", e))
                    }
                }
            },
            None => {
                error!("Invalid challenge response format. Full response: {response_json:?}");
                Err(anyhow!("Invalid challenge response format from server"))
            }
        }
    }
    
    /// Get a fresh POW response
    async fn get_fresh_pow_response(&mut self) -> Result<String> {
        debug!("Requesting new POW challenge");
        let challenge = self.get_pow_challenge().await?;
        
        debug!("Solving POW challenge with difficulty: {}", challenge.difficulty);
        let pow_response = self.pow_solver.solve_challenge(&challenge)?;
        
        
        Ok(pow_response)
    }
    
    /// Create a new chat session
    pub async fn create_chat_session(&mut self) -> Result<String> {
        debug!("Creating new chat session");
        let response: Value = self.make_request(
            "POST",
            "/chat_session/create",
            json!({"character_id": null}),
            false
        ).await?;
        
        debug!("Chat session creation response: {response:?}");
        
        // Extract the session ID from the response
        match &response.get("data").and_then(|d| d.get("biz_data")).and_then(|b| b.get("id")) {
            Some(Value::String(id)) => {
                info!("Created chat session with ID: {id}");
                Ok(id.clone())
            },
            _ => {
                error!("Invalid session creation response format. Response: {response:?}");
                Err(anyhow!("Invalid session creation response format from server"))
            }
        }
    }
    
    /// Send a message and get a streaming response
    pub async fn chat_completion(
        &mut self,
        chat_session_id: &str,
        prompt: &str,
        parent_message_id: Option<&str>,
        thinking_mode: ThinkingMode,
        search_mode: SearchMode,
        system_prompt: Option<&str>,
    ) -> Result<String> {
        info!("Starting chat completion for session: {chat_session_id}");
        debug!("Prompt length: {} chars", prompt.len());
        trace!("Parent message ID: {parent_message_id:?}");
        trace!("Thinking mode enabled: {}, Search mode enabled: {}", thinking_mode.as_bool(), search_mode.as_bool());
        
        if prompt.is_empty() {
            return Err(anyhow!("Prompt must be a non-empty string"));
        }
        
        if chat_session_id.is_empty() {
            return Err(anyhow!("Chat session ID must be a non-empty string"));
        }
        
        // Build the full prompt including conversation history and system prompt
        let mut full_prompt = String::new();
        
        // Add system prompt if provided
        if self.message_counter == 0 {
            if let Some(sys_prompt) = system_prompt {
                full_prompt.push_str("System: ");
                full_prompt.push_str(sys_prompt);
                full_prompt.push_str("\n\n");
            }
        }
        
        // Add conversation history
        
        // Add current user message
        full_prompt.push_str("User: ");
        full_prompt.push_str(prompt);
        self.message_history.push(ChatMessage {
            role: "user".to_string(),
            content: prompt.to_string(),
        });
        
        // Set parent_message_id: first request is null, then increment from 2
        let parent_id = if self.message_counter == 0 { None } else { Some(format!("{}", self.message_counter * 2)) };
        self.message_counter += 1;
        
        let json_data = json!({
            "chat_session_id": chat_session_id,
            "parent_message_id": parent_id,
            "prompt": full_prompt,
            "ref_file_ids": [],
            "thinking_enabled": thinking_mode.as_bool(),
            "search_enabled": search_mode.as_bool(),
        });
        
        debug!("Chat completion request data prepared");
        trace!("Request JSON: {json_data}");
        
        // Get POW response (use cached if available, or get fresh one)
        let pow_response = self.get_fresh_pow_response().await?;
        
        // Prepare headers with POW response
        debug!("Preparing request headers with verification...");
        let mut headers = self.default_headers(Some(&pow_response));
        
        // Add cookies
        debug!("Processing session cookies...");
        let cookies_map = match &self.session.cookies {
            Value::Object(obj) => {
                debug!("Found {} cookie entries in session", obj.len());
                obj
            },
            _ => {
                error!("Invalid cookies format in session - not an object");
                return Err(anyhow!("Invalid cookies format in session"));
            }
        };
        
        let mut cookie_str = String::new();
        let mut cookie_count = 0;
        for (key, value) in cookies_map {
            if let Value::String(val) = value {
                if !cookie_str.is_empty() {
                    cookie_str.push_str("; ");
                }
                cookie_str.push_str(&format!("{key}={val}"));
                cookie_count += 1;
            }
        }
        
        if !cookie_str.is_empty() {
            headers.insert("Cookie", HeaderValue::from_str(&cookie_str)?);
            debug!("Added {} cookies to request headers ({} chars total)", cookie_count, cookie_str.len());
        } else {
            warn!("No valid cookies found for chat completion request");
        }
        
        // Make streaming request
        debug!("About to send HTTP POST request to chat completion endpoint...");
        let url = format!("{BASE_URL}/chat/completion");
        debug!("Target URL: {url}");
        debug!("Request headers count: {}", headers.len());
        let response = match self.http
            .post(&url)
            .headers(headers)
            .json(&json_data)
            .send()
            .await
        {
            Ok(resp) => {
                debug!("HTTP request completed successfully");
                debug!("Response status: {}", resp.status());
                debug!("Response headers count: {}", resp.headers().len());
                
                // Log all response headers for debugging
                for (name, value) in resp.headers() {
                    debug!("Response header: {name}: {value:?}");
                }
                
                if !resp.status().is_success() {
                    let status = resp.status();
                    warn!("HTTP request failed with status: {status}");
                    let error_text = match resp.text().await {
                        Ok(text) => {
                            debug!("Error response body length: {}", text.len());
                            trace!("Error response body: {text}");
                            text
                        },
                        Err(e) => {
                            error!("Failed to read error response body: {e}");
                            format!("Failed to read response: {e}")
                        }
                    };
                    
                    error!("Chat completion failed: {status} - {error_text}");
                    match status.as_u16() {
                        401 => return Err(anyhow!("Authentication error: Invalid or expired token. Please check your auth_token file.")),
                        403 => return Err(anyhow!("Forbidden: Invalid cookies or IP blocked. Please refresh your cookies.")),
                        429 => return Err(anyhow!("Rate limit exceeded. Please wait and try again.")),
                        _ => return Err(anyhow!("API request failed: HTTP {} - {}", status, error_text)),
                    }
                }
                
                debug!("HTTP response is successful, proceeding to process stream...");
                resp
            },
            Err(e) => {
                error!("Network error during HTTP request: {e}");
                error!("Error type: {e:?}");
                return Err(anyhow!("Network error occurred during streaming: {}", e));
            }
        };
        
        // Process the SSE stream properly
        debug!("Processing SSE stream...");
        let mut result = String::new();
        let mut stream = response.bytes_stream();
        let mut buffer = String::new();
        let mut finished = false;
        let mut chunk_count = 0;
        
        while let Some(chunk_result) = stream.next().await {
            let chunk_bytes = match chunk_result {
                Ok(c) => c,
                Err(e) => {
                    error!("Error reading stream chunk: {e}");
                    break;
                }
            };
            
            chunk_count += 1;
            let chunk_str = String::from_utf8_lossy(&chunk_bytes);
            buffer.push_str(&chunk_str);
            
            trace!("Received chunk #{}, buffer length: {}", chunk_count, buffer.len());
            
            // Process complete lines from the buffer
            while let Some(newline_pos) = buffer.find('\n') {
                let line = buffer[..newline_pos].to_string();
                buffer = buffer[newline_pos + 1..].to_string();
                let line = line.trim();
                
                if line.is_empty() {
                    continue;
                }
                
                trace!("SSE line: {line}");
                
                // Handle different SSE event types
                if let Some(event_str) = line.strip_prefix("event: ") {
                    match event_str {
                        "finish" => {
                            debug!("Received finish event, stream completed");
                            finished = true;
                            break;
                        }
                        "close" => {
                            debug!("Received close event");
                            finished = true;
                            break;
                        }
                        _ => {
                            trace!("SSE event: {event_str}");
                        }
                    }
                    continue;
                }
                
                if let Some(data_str) = line.strip_prefix("data: ") {
                    if data_str == "[DONE]" {
                        debug!("Received stream completion marker [DONE]");
                        finished = true;
                        break;
                    }
                    
                    match serde_json::from_str::<Value>(data_str) {
                        Ok(data) => {
                            debug!("Parsed SSE data: {data:?}");
                            
                            // Handle DeepSeek's streaming format
                            if let Some(value) = data.get("v") {
                                let mut content_added = false;
                                
                                // Check for the specific streaming format with path/operation first
                                if let Some(path) = data.get("p").and_then(|p| p.as_str()) {
                                    if let Some(operation) = data.get("o").and_then(|o| o.as_str()) {
                                        if path == "response/content" && operation == "APPEND" {
                                            if let Some(text) = value.as_str() {
                                                result.push_str(text);
                                                trace!("Appended response content: {text}");
                                                content_added = true;
                                            }
                                        }
                                    }
                                }
                                
                                // If no content was added via streaming format, check if this is thinking content
                                // Thinking content comes as just {"v": "text"} without path/operation
                                if !content_added {
                                    // Check if this is thinking content (no path/operation fields)
                                    if data.get("p").is_none() && data.get("o").is_none() {
                                        if let Some(text) = value.as_str() {
                                            result.push_str(text);
                                            trace!("Appended thinking content: {text}");
                                            content_added = true;
                                        }
                                    }
                                }
                                
                                // If still no content was added, try fallback extraction
                                if !content_added {
                                    if let Some(content) = extract_content_from_response(&data) {
                                        result.push_str(&content);
                                        trace!("Added fallback content: {content}");
                                    }
                                }
                            }
                            
                            // Check for completion signals
                            if let Some(status) = data.get("status") {
                                if status.as_str() == Some("completed") || status.as_str() == Some("FINISHED") {
                                    debug!("Stream finished with completed status");
                                    finished = true;
                                    break;
                                }
                            }
                        },
                        Err(e) => {
                            warn!("Error parsing SSE JSON: {e} - Data: {data_str}");
                        }
                    }
                }
            }
            
            if finished {
                break;
            }
        }
        
        info!("Chat completion finished, processed {} chunks, result length: {}", chunk_count, result.len());
        if result.is_empty() {
            warn!("Empty result from SSE stream, buffer content: {:?}", buffer);
        }
        
        // Add assistant response to message history for context retention
        if !result.is_empty() {
            self.message_history.push(ChatMessage {
                role: "assistant".to_string(),
                content: result.clone(),
            });
            debug!("Added assistant response to message history");
        }
        
        Ok(result)
    }
    
    /// Get conversation history for a chat session
    pub async fn get_chat_history(&mut self, chat_session_id: &str) -> Result<Value> {
        debug!("Getting chat history for session: {chat_session_id}");
        
        let url = format!("{BASE_URL}/chat/history_messages?chat_session_id={chat_session_id}&cache_version=8");
        debug!("History URL: {url}");
        
        let response: Value = self.make_request(
            "GET",
            &format!("/chat/history_messages?chat_session_id={chat_session_id}&cache_version=8"),
            json!(null),
            false
        ).await?;
        
        debug!("Chat history response received");
        Ok(response)
    }
}

// Extract content from DeepSeek response format
fn extract_content_from_response(data: &Value) -> Option<String> {
    // Try direct content field
    if let Some(content) = data.get("content") {
        if let Some(text) = content.as_str() {
            return Some(text.to_string());
        }
    }
    
    // Try v.response.content format
    if let Some(response) = data.get("v").and_then(|v| v.get("response")) {
        if let Some(content) = response.get("content") {
            if let Some(text) = content.as_str() {
                return Some(text.to_string());
            }
        }
    }
    
    // Try OpenAI format as fallback
    if let Some(choices) = data.get("choices").and_then(|c| c.as_array()) {
        if let Some(choice) = choices.first() {
            if let Some(delta) = choice.get("delta") {
                if let Some(content) = delta.get("content") {
                    if let Some(text) = content.as_str() {
                        return Some(text.to_string());
                    }
                }
            }
        }
    }
    
    None
}

// Helper function to load cookies from file
pub fn load_cookies(cookie_file: &Path) -> Result<serde_json::Value> {
    debug!("Loading cookies from file: {cookie_file:?}");
    
    if !cookie_file.exists() {
        return Err(anyhow!("Cookie file does not exist at {:?}", cookie_file));
    }
    
    let cookie_data = fs::read_to_string(cookie_file)?;
    let cookies: Value = serde_json::from_str(&cookie_data)?;
    
    debug!("Successfully loaded cookies file, {} bytes", cookie_data.len());
    Ok(cookies.get("cookies").cloned().unwrap_or(json!({})))
}

// Helper function to extract configuration help text
pub fn get_config_help(file_name: &str) -> String {
    match file_name {
        "deepseek_auth_token" => "To get your DeepSeek auth token:
1. Go to chat.deepseek.com in your browser
2. Open Developer Tools (F12 or right-click and select 'Inspect')
3. Go to the Network tab
4. Refresh the page or make a request
5. Look for requests to the DeepSeek API
6. In the 'Headers' tab, find 'Request Headers'
7. Look for the 'Authorization' header with format 'Bearer {token}'
8. Copy the token part (without 'Bearer ') and save it to this folder with filename: deepseek_auth_token".to_string(),
        
        "deepseek_cookies" => "The DeepSeek API requires Cloudflare cookies.
Please run the Python bypass script from deepseek4free to generate these cookies:
1. Run the bypass.py script from deepseek4free/dsk/
2. Copy the resulting cookies.json file to this folder with filename: deepseek_cookies".to_string(),
        
        _ => format!("Configuration file {file_name} is missing."),
    }
}