// backend.cpp (Corrected)
#include "httplib.h"
#include "wren.h"
#include <iostream>
#include <string>

// A struct to hold the response data for our foreign object
struct ResponseData {
    bool isError;
    int statusCode;
    std::string body;
};

// --- Response Class Foreign Methods ---

void responseAllocate(WrenVM* vm) {
    // This is the constructor for the Response class.
    ResponseData* data = (ResponseData*)wrenSetSlotNewForeign(vm, 0, 0, sizeof(ResponseData));
    data->isError = false;
    data->statusCode = 0;
}

void responseIsError(WrenVM* vm) {
    ResponseData* data = (ResponseData*)wrenGetSlotForeign(vm, 0);
    wrenSetSlotBool(vm, 0, data->isError);
}

void responseStatusCode(WrenVM* vm) {
    ResponseData* data = (ResponseData*)wrenGetSlotForeign(vm, 0);
    wrenSetSlotDouble(vm, 0, data->statusCode);
}

void responseBody(WrenVM* vm) {
    ResponseData* data = (ResponseData*)wrenGetSlotForeign(vm, 0);
    wrenSetSlotBytes(vm, 0, data->body.c_str(), data->body.length());
}

void responseJson(WrenVM* vm) {
    // For a real implementation, you would use a JSON library here.
    // For this example, we just return the body text.
    ResponseData* data = (ResponseData*)wrenGetSlotForeign(vm, 0);
    wrenSetSlotBytes(vm, 0, data->body.c_str(), data->body.length());
}

// --- Requests Class Foreign Methods ---

void requestsGet(WrenVM* vm) {
    const char* url = wrenGetSlotString(vm, 1);
    // TODO: Handle headers from slot 2.

    httplib::Client cli("jsonplaceholder.typicode.com");
    auto res = cli.Get("/posts/1");

    // CHANGED: We need two slots: one for the Response class, one for the new instance.
    wrenEnsureSlots(vm, 2);

    // CHANGED: Get the 'Response' class from the 'requests' module and put it in slot 1.
    wrenGetVariable(vm, "requests", "Response", 1);

    // CHANGED: Create a new foreign object instance of the class in slot 1.
    // The new instance is placed in slot 0, which becomes the return value.
    ResponseData* data = (ResponseData*)wrenSetSlotNewForeign(vm, 0, 1, sizeof(ResponseData));

    if (res) {
        data->isError = false;
        data->statusCode = res->status;
        data->body = res->body;
    } else {
        data->isError = true;
        data->statusCode = -1;
        data->body = "GET request failed.";
    }
}

void requestsPost(WrenVM* vm) {
    const char* url = wrenGetSlotString(vm, 1);
    const char* body = wrenGetSlotString(vm, 2);
    const char* contentType = wrenGetSlotString(vm, 3);
    // TODO: Handle headers from slot 4.

    httplib::Client cli("jsonplaceholder.typicode.com");
    auto res = cli.Post("/posts", body, contentType);

    // CHANGED: We need two slots: one for the Response class, one for the new instance.
    wrenEnsureSlots(vm, 2);

    // CHANGED: Get the 'Response' class from the 'requests' module and put it in slot 1.
    wrenGetVariable(vm, "requests", "Response", 1);

    // CHANGED: Create a new foreign object instance of the class in slot 1.
    // The new instance is placed in slot 0, which becomes the return value.
    ResponseData* data = (ResponseData*)wrenSetSlotNewForeign(vm, 0, 1, sizeof(ResponseData));
    
    if (res) {
        data->isError = false;
        data->statusCode = res->status;
        data->body = res->body;
    } else {
        data->isError = true;
        data->statusCode = -1;
        data->body = "POST request failed.";
    }
}


// --- FFI Binding Functions ---

WrenForeignMethodFn bindForeignMethod(WrenVM* vm, const char* module,
    const char* className, bool isStatic, const char* signature) {
    if (strcmp(module, "requests") != 0) return NULL;

    if (strcmp(className, "Requests") == 0 && isStatic) {
        if (strcmp(signature, "get_(_,_)") == 0) return requestsGet;
        if (strcmp(signature, "post_(_,_,_,_)") == 0) return requestsPost;
    }

    if (strcmp(className, "Response") == 0 && !isStatic) {
        if (strcmp(signature, "isError") == 0) return responseIsError;
        if (strcmp(signature, "statusCode") == 0) return responseStatusCode;
        if (strcmp(signature, "body") == 0) return responseBody;
        if (strcmp(signature, "json()") == 0) return responseJson;
    }

    return NULL;
}

WrenForeignClassMethods bindForeignClass(WrenVM* vm, const char* module, const char* className) {
    WrenForeignClassMethods methods = {0};
    if (strcmp(module, "requests") == 0) {
        if (strcmp(className, "Response") == 0) {
            methods.allocate = responseAllocate;
        }
    }
    return methods;
}