import { readFile, mkdir, writeFile } from "fs/promises";
import { existsSync } from "fs";
import { join } from "path";
import { homedir } from "os";
import type {
DrawThingsConfig,
Txt2ImgRequest,
Img2ImgRequest,
GenerationResponse,
} from "../types.js";
/**
* Draw Things HTTP API Client
* Communicates with the Draw Things app running on localhost
*/
export class DrawThingsClient {
private baseUrl: string;
private outputDir: string;
constructor() {
const host = process.env.DRAWTHINGS_HOST || "localhost";
const port = process.env.DRAWTHINGS_PORT || "7860";
this.baseUrl = `http://${host}:${port}`;
this.outputDir =
process.env.DRAWTHINGS_OUTPUT_DIR ||
join(homedir(), "Pictures", "drawthings-mcp");
}
/**
* Check if the Draw Things API server is running
*/
async checkStatus(): Promise<{ running: boolean; message: string }> {
try {
const response = await fetch(this.baseUrl);
if (response.ok) {
return {
running: true,
message: `Draw Things API server is running at ${this.baseUrl}`,
};
}
return {
running: false,
message: `Draw Things API server returned status ${response.status}`,
};
} catch (error) {
return {
running: false,
message: `Cannot connect to Draw Things API at ${this.baseUrl}. Make sure Draw Things is running and the API Server is enabled in settings.`,
};
}
}
/**
* Get the current Draw Things configuration
*/
async getConfig(): Promise<DrawThingsConfig> {
const response = await fetch(this.baseUrl);
if (!response.ok) {
throw new Error(
`Failed to get config: ${response.status} ${response.statusText}`
);
}
return (await response.json()) as DrawThingsConfig;
}
/**
* Generate an image from a text prompt (txt2img)
*/
async txt2img(request: Txt2ImgRequest): Promise<GenerationResponse> {
const response = await fetch(`${this.baseUrl}/sdapi/v1/txt2img`, {
method: "POST",
headers: {
"Content-Type": "application/json",
},
body: JSON.stringify({
prompt: request.prompt,
negative_prompt: request.negative_prompt || "",
width: request.width || 512,
height: request.height || 512,
steps: request.steps || 20,
cfg_scale: request.cfg_scale || 7.5,
seed: request.seed ?? -1,
sampler: request.sampler,
batch_size: request.batch_size || 1,
...(request.model && { model: request.model }),
}),
});
if (!response.ok) {
const errorText = await response.text();
throw new Error(
`txt2img failed: ${response.status} ${response.statusText} - ${errorText}`
);
}
return (await response.json()) as GenerationResponse;
}
/**
* Transform an image using a prompt (img2img)
*/
async img2img(request: Img2ImgRequest): Promise<GenerationResponse> {
const response = await fetch(`${this.baseUrl}/sdapi/v1/img2img`, {
method: "POST",
headers: {
"Content-Type": "application/json",
},
body: JSON.stringify({
prompt: request.prompt,
init_images: request.init_images,
negative_prompt: request.negative_prompt || "",
denoising_strength: request.denoising_strength ?? 0.75,
steps: request.steps || 20,
cfg_scale: request.cfg_scale || 7.5,
seed: request.seed ?? -1,
sampler: request.sampler,
batch_size: request.batch_size || 1,
}),
});
if (!response.ok) {
const errorText = await response.text();
throw new Error(
`img2img failed: ${response.status} ${response.statusText} - ${errorText}`
);
}
return (await response.json()) as GenerationResponse;
}
/**
* Read an image file and return as base64
*/
async readImageAsBase64(imagePath: string): Promise<string> {
const absolutePath = imagePath.startsWith("~")
? join(homedir(), imagePath.slice(1))
: imagePath;
const buffer = await readFile(absolutePath);
return buffer.toString("base64");
}
/**
* Save a base64 image to disk
*/
async saveImage(
base64Data: string,
customPath?: string
): Promise<string> {
const outputDir = customPath
? join(customPath, "..")
: this.outputDir;
// Ensure output directory exists
if (!existsSync(outputDir)) {
await mkdir(outputDir, { recursive: true });
}
const filename =
customPath ||
join(this.outputDir, `image_${Date.now()}.png`);
// Remove data URL prefix if present
const base64Clean = base64Data.replace(/^data:image\/\w+;base64,/, "");
const buffer = Buffer.from(base64Clean, "base64");
await writeFile(filename, buffer);
return filename;
}
}
