import type { IncomingMessage, ServerResponse } from "node:http";
import { dispatchSlashCommand } from "../slash/dispatch.ts";
import { normalizeChatImages } from "../services/chat-images.ts";
import type { WebUiContext } from "../types/context.ts";
import { json, readBody } from "../http/request.ts";

async function trySlashDispatch(
	msg: string,
	imgs: ReturnType<typeof normalizeChatImages>,
	sendCmd: WebUiContext["rpc"]["sendCmd"],
): Promise<Awaited<ReturnType<typeof dispatchSlashCommand>> | null> {
	const trimmed = msg.trim();
	if (!trimmed.startsWith("/")) return null;
	const slash = await dispatchSlashCommand(trimmed, sendCmd);
	return slash?.handled ? slash : null;
}

export function handleChatRoute(
	req: IncomingMessage,
	res: ServerResponse,
	ctx: WebUiContext,
	pathname: string,
): boolean {
	const { sendCmd, submitPrompt } = ctx.rpc;

	if (req.method === "POST" && pathname === "/api/chat") {
		void readBody(req)
			.then(async ({ message, images, streamingBehavior }) => {
				const msg = typeof message === "string" ? message : "";
				const imgs = normalizeChatImages(images);
				if (!msg.trim() && !imgs?.length) throw new Error("消息不能为空");
				if (imgs?.length) console.log(`[webui] chat: ${imgs.length} image(s), message=${msg.length} chars`);

				const slash = await trySlashDispatch(msg, imgs, sendCmd);
				if (slash) {
					return json(res, { ok: true, slash: true, ...slash });
				}

				const behavior =
					streamingBehavior === "steer" || streamingBehavior === "followUp"
						? streamingBehavior
						: undefined;
				submitPrompt({ message: msg, images: imgs, streamingBehavior: behavior });
				return json(res, { ok: true, accepted: true }, 202);
			})
			.catch((err) => json(res, { error: err.message }, 500));
		return true;
	}

	if (req.method === "POST" && pathname === "/api/steer") {
		void readBody(req)
			.then(async ({ message, images }) => {
				const msg = typeof message === "string" ? message.trim() : "";
				const imgs = normalizeChatImages(images);
				if (!msg && !imgs?.length) throw new Error("消息不能为空");
				const result = await sendCmd({ type: "steer", message: msg, images: imgs });
				if (!result.success) throw new Error(result.error || "steer 失败");
				json(res, { ok: true });
			})
			.catch((err) => json(res, { error: err.message }, 500));
		return true;
	}

	if (req.method === "POST" && pathname === "/api/follow-up") {
		void readBody(req)
			.then(async ({ message, images }) => {
				const msg = typeof message === "string" ? message.trim() : "";
				const imgs = normalizeChatImages(images);
				if (!msg && !imgs?.length) throw new Error("消息不能为空");
				const result = await sendCmd({ type: "follow_up", message: msg, images: imgs });
				if (!result.success) throw new Error(result.error || "follow_up 失败");
				json(res, { ok: true });
			})
			.catch((err) => json(res, { error: err.message }, 500));
		return true;
	}

	if (req.method === "POST" && pathname === "/api/bash") {
		void readBody(req)
			.then(async ({ command, excludeFromContext }) => {
				const cmd = typeof command === "string" ? command.trim() : "";
				if (!cmd) throw new Error("命令不能为空");
				const result = await sendCmd({
					type: "bash",
					command: cmd,
					excludeFromContext: excludeFromContext === true,
				});
				if (!result.success) throw new Error(result.error || "命令执行失败");
				json(res, result.data);
			})
			.catch((err) => json(res, { error: err.message }, 500));
		return true;
	}

	if (req.method === "GET" && pathname === "/api/events") {
		res.writeHead(200, {
			"Content-Type": "text/event-stream",
			"Cache-Control": "no-cache",
			Connection: "keep-alive",
		});
		ctx.rpc.connectSseClient(res);
		req.on("close", () => ctx.rpc.removeSseClient(res));
		return true;
	}

	if (req.method === "POST" && pathname === "/api/messages") {
		void sendCmd({ type: "get_messages" })
			.then((r: any) => (r.success ? json(res, r.data) : json(res, { error: r.error }, 500)))
			.catch((err) => json(res, { error: err.message }, 500));
		return true;
	}

	if (req.method === "POST" && pathname === "/api/abort") {
		void sendCmd({ type: "abort" })
			.then(() => json(res, { ok: true }))
			.catch((err) => json(res, { error: err.message }, 500));
		return true;
	}

	if (req.method === "POST" && pathname === "/api/abort-retry") {
		void sendCmd({ type: "abort_retry" })
			.then(() => json(res, { ok: true }))
			.catch((err) => json(res, { error: err.message }, 500));
		return true;
	}

	return false;
}