#include "ShellExportHandler.h"
#include <algorithm>
#include <regex>
#include <stdexcept>

HttpResponse ShellExportHandler::HandleShrinkwrapShellRequest(const HttpRequest& request) {
    std::string validation_error;
    if (!ValidateHttpRequest(request, validation_error)) {
        return FormatErrorResponse(400, validation_error);
    }
    
    try {
        ShrinkwrapShellRequest shrinkwrap_request = ParseShrinkwrapRequest(request.body);
        ShrinkwrapShellResult result = ShrinkwrapManager::Instance().ExecuteShrinkwrapShell(shrinkwrap_request);
        
        if (result.success) {
            return FormatSuccessResponse(result);
        } else {
            return FormatErrorResponse(500, result.error_message);
        }
        
    } catch (const std::exception& e) {
        return FormatErrorResponse(500, "Request processing error: " + std::string(e.what()));
    } catch (...) {
        return FormatErrorResponse(500, "Unknown error during shrinkwrap shell export");
    }
}

std::string ShellExportHandler::ExtractJsonValue(const std::string& json, const std::string& key) {
    try {
        std::string search_pattern = "\\\"" + key + "\\\"\\s*:\\s*\\\"([^\\\"]*?)\\\"";
        std::regex pattern(search_pattern);
        std::smatch match;
        
        if (std::regex_search(json, match, pattern)) {
            return match[1].str();
        }
        
        std::string search_pattern2 = "\\\"" + key + "\\\"\\s*:\\s*([^,}\\s]+)";
        std::regex pattern2(search_pattern2);
        
        if (std::regex_search(json, match, pattern2)) {
            std::string value = match[1].str();
            if (value.front() == '\"' && value.back() == '\"') {
                value = value.substr(1, value.length() - 2);
            }
            return value;
        }
        
    } catch (...) {
        // Error handling
    }
    
    return "";
}

bool ShellExportHandler::ExtractJsonBoolValue(const std::string& json, const std::string& key, bool default_value) {
    std::string value = ExtractJsonValue(json, key);
    if (value.empty()) {
        return default_value;
    }
    
    std::string lower_value = value;
    std::transform(lower_value.begin(), lower_value.end(), lower_value.begin(), ::tolower);
    
    return (lower_value == "true" || lower_value == "1");
}

int ShellExportHandler::ExtractJsonIntValue(const std::string& json, const std::string& key, int default_value) {
    std::string value = ExtractJsonValue(json, key);
    if (value.empty()) {
        return default_value;
    }
    
    try {
        return std::stoi(value);
    } catch (...) {
        return default_value;
    }
}

double ShellExportHandler::ExtractJsonDoubleValue(const std::string& json, const std::string& key, double default_value) {
    std::string value = ExtractJsonValue(json, key);
    if (value.empty()) {
        return default_value;
    }
    
    try {
        return std::stod(value);
    } catch (...) {
        return default_value;
    }
}

std::string ShellExportHandler::EscapeJsonString(const std::string& input) {
    std::string output;
    output.reserve(input.length() * 2);
    
    for (char c : input) {
        switch (c) {
            case '\"': output += "\\\""; break;
            case '\\': output += "\\\\"; break;
            case '\b': output += "\\b"; break;
            case '\f': output += "\\f"; break;
            case '\n': output += "\\n"; break;
            case '\r': output += "\\r"; break;
            case '\t': output += "\\t"; break;
            default:
                if (c < 0x20) {
                    char buffer[7];
                    snprintf(buffer, sizeof(buffer), "\\u%04x", static_cast<unsigned char>(c));
                    output += buffer;
                } else {
                    output += c;
                }
                break;
        }
    }
    
    return output;
}

bool ShellExportHandler::ValidateHttpRequest(const HttpRequest& request, std::string& error_message) {
    if (request.method != "POST") {
        error_message = "Method not allowed. Only POST requests are supported.";
        return false;
    }
    
    if (request.body.empty()) {
        error_message = "Request body is empty";
        return false;
    }
    
    std::string trimmed_body = Trim(request.body);
    if (!StartsWith(trimmed_body, "{") || !EndsWith(trimmed_body, "}")) {
        error_message = "Invalid JSON format";
        return false;
    }
    
    return true;
}

ShrinkwrapShellRequest ShellExportHandler::ParseShrinkwrapRequest(const std::string& json_body) {
    ShrinkwrapShellRequest request;
    
    request.software_type = ExtractJsonValue(json_body, "software_type");
    if (request.software_type.empty()) {
        request.software_type = "creo";
    }
    
    std::string project_name = ExtractJsonValue(json_body, "project_name");
    if (!project_name.empty()) {
        request.project_name = project_name;
    }
    
    std::string method = ExtractJsonValue(json_body, "method");
    if (!method.empty()) {
        request.method = method;
    }
    
    // 解析 component_path 参数（可选，用于指定子装配体）
    request.component_path = ExtractJsonValue(json_body, "component_path");
    
    request.quality = ExtractJsonIntValue(json_body, "quality", 8);
    request.chord_height = ExtractJsonDoubleValue(json_body, "chord_height", 0.1);
    request.fill_holes = ExtractJsonBoolValue(json_body, "fill_holes", true);
    request.ignore_small_surfaces = ExtractJsonBoolValue(json_body, "ignore_small_surfaces", true);
    request.small_surface_percentage = ExtractJsonDoubleValue(json_body, "small_surface_percentage", 0.5);
    request.ignore_quilts = ExtractJsonBoolValue(json_body, "ignore_quilts", true);
    request.ignore_skeleton = ExtractJsonBoolValue(json_body, "ignore_skeleton", true);
    request.assign_mass_properties = ExtractJsonBoolValue(json_body, "assign_mass_properties", false);
    
    request.output_file_path = ExtractJsonValue(json_body, "output_file_path");
    request.output_type = ExtractJsonValue(json_body, "output_type");
    if (request.output_type.empty()) {
        request.output_type = "solid_surface";
    }
    request.preset = ExtractJsonValue(json_body, "preset");
    
    // 解析超时参数，默认30秒，最大300秒
    request.timeout_seconds = ExtractJsonIntValue(json_body, "timeout_seconds", 30);
    if (request.timeout_seconds < 10) {
        request.timeout_seconds = 10;  // 最小10秒
    }
    if (request.timeout_seconds > 300) {
        request.timeout_seconds = 300; // 最大300秒
    }
    
    return request;
}

HttpResponse ShellExportHandler::FormatSuccessResponse(const ShrinkwrapShellResult& result) {
    HttpResponse response;
    response.status_code = 200;
    
    std::ostringstream json;
    json << "{"
         << "\"success\": true,"
         << "\"message\": \"" << EscapeJsonString(result.message) << "\","
         << "\"data\": {"
         << "\"output_file\": \"" << EscapeJsonString(result.parameters.output_file_path) << "\","
         << "\"file_size\": \"" << EscapeJsonString(result.parameters.output_file_size) << "\","
         << "\"export_time\": \"" << EscapeJsonString(result.parameters.shrinkwrap_time) << "\","
         << "\"parameters_used\": {"
         << "\"method\": \"" << EscapeJsonString(result.parameters.method) << "\","
         << "\"quality\": " << result.parameters.quality << ","
         << "\"fill_holes\": " << (result.parameters.fill_holes ? "true" : "false") << ","
         << "\"ignore_small_surfaces\": " << (result.parameters.ignore_small_surfaces ? "true" : "false") << ","
         << "\"small_surface_percentage\": " << result.parameters.small_surface_percentage << ","
         << "\"ignore_quilts\": " << (result.parameters.ignore_quilts ? "true" : "false") << ","
         << "\"ignore_skeleton\": " << (result.parameters.ignore_skeleton ? "true" : "false") << ","
         << "\"assign_mass_properties\": " << (result.parameters.assign_mass_properties ? "true" : "false")
         << "}"
         << "},"
         << "\"error\": null"
         << "}";
    
    response.body = json.str();
    return response;
}

HttpResponse ShellExportHandler::FormatErrorResponse(int status_code, const std::string& error_message) {
    HttpResponse response;
    response.status_code = status_code;
    
    std::ostringstream json;
    json << "{"
         << "\"success\": false,"
         << "\"message\": null,"
         << "\"data\": null,"
         << "\"error\": \"" << EscapeJsonString(error_message) << "\""
         << "}";
    
    response.body = json.str();
    return response;
}

std::string ShellExportHandler::Trim(const std::string& str) {
    size_t start = str.find_first_not_of(" \t\n\r");
    if (start == std::string::npos) {
        return "";
    }
    
    size_t end = str.find_last_not_of(" \t\n\r");
    return str.substr(start, end - start + 1);
}

bool ShellExportHandler::StartsWith(const std::string& str, const std::string& prefix) {
    return str.length() >= prefix.length() && 
           str.compare(0, prefix.length(), prefix) == 0;
}

bool ShellExportHandler::EndsWith(const std::string& str, const std::string& suffix) {
    return str.length() >= suffix.length() && 
           str.compare(str.length() - suffix.length(), suffix.length(), suffix) == 0;
}