/**
 * HTTP transport layer for the Huskies API client.
 * Provides the low-level `requestJson` helper, the `callMcpTool` function
 * for MCP JSON-RPC calls, the `resolveWsHost` utility, and the `api`
 * object exposing all REST endpoints.
 */

import type {
	AllTokenUsageResponse,
	AnthropicModelInfo,
	CommandOutput,
	FileEntry,
	OAuthStatus,
	SearchResult,
	TestResultsResponse,
	TokenCostResponse,
	WorkItemContent,
} from "./types";

/** Base URL prefix for all REST API requests in production. */
export const DEFAULT_API_BASE = "/api";

/**
 * Resolve the WebSocket host to connect to.
 * In development, uses the injected port (or 3001); in production, uses the
 * current page's host so the socket connects to the same origin.
 */
export function resolveWsHost(
	isDev: boolean,
	envPort: string | undefined,
	locationHost: string,
): string {
	return isDev ? `127.0.0.1:${envPort || "3001"}` : locationHost;
}

function buildApiUrl(path: string, baseUrl = DEFAULT_API_BASE): string {
	return `${baseUrl}${path}`;
}

async function requestJson<T>(
	path: string,
	options: RequestInit = {},
	baseUrl = DEFAULT_API_BASE,
): Promise<T> {
	const res = await fetch(buildApiUrl(path, baseUrl), {
		headers: {
			"Content-Type": "application/json",
			...(options.headers ?? {}),
		},
		...options,
	});

	if (!res.ok) {
		const text = await res.text();
		throw new Error(text || `Request failed (${res.status})`);
	}

	return res.json() as Promise<T>;
}

/**
 * Invoke an MCP tool via the server's JSON-RPC `/mcp` endpoint.
 * Returns the first text content block from the tool result, or an empty
 * string if the result has no content.
 */
export async function callMcpTool(
	toolName: string,
	args: Record<string, unknown>,
): Promise<string> {
	const res = await fetch("/mcp", {
		method: "POST",
		headers: { "Content-Type": "application/json" },
		body: JSON.stringify({
			jsonrpc: "2.0",
			id: 1,
			method: "tools/call",
			params: { name: toolName, arguments: args },
		}),
	});
	const json = await res.json();
	if (json.error) {
		throw new Error(json.error.message);
	}
	const text = json.result?.content?.[0]?.text ?? "";
	return text;
}

/** Typed REST and MCP wrappers for all Huskies server endpoints. */
export const api = {
	getCurrentProject(baseUrl?: string) {
		return requestJson<string | null>("/project", {}, baseUrl);
	},
	getKnownProjects(baseUrl?: string) {
		return requestJson<string[]>("/projects", {}, baseUrl);
	},
	forgetKnownProject(path: string, baseUrl?: string) {
		return requestJson<boolean>(
			"/projects/forget",
			{ method: "POST", body: JSON.stringify({ path }) },
			baseUrl,
		);
	},
	openProject(path: string, baseUrl?: string) {
		return requestJson<string>(
			"/project",
			{ method: "POST", body: JSON.stringify({ path }) },
			baseUrl,
		);
	},
	closeProject(baseUrl?: string) {
		return requestJson<boolean>("/project", { method: "DELETE" }, baseUrl);
	},
	getModelPreference(baseUrl?: string) {
		return requestJson<string | null>("/model", {}, baseUrl);
	},
	setModelPreference(model: string, baseUrl?: string) {
		return requestJson<boolean>(
			"/model",
			{ method: "POST", body: JSON.stringify({ model }) },
			baseUrl,
		);
	},
	getOllamaModels(baseUrlParam?: string, baseUrl?: string) {
		const url = new URL(
			buildApiUrl("/ollama/models", baseUrl),
			window.location.origin,
		);
		if (baseUrlParam) {
			url.searchParams.set("base_url", baseUrlParam);
		}
		return requestJson<string[]>(url.pathname + url.search, {}, "");
	},
	getAnthropicApiKeyExists(baseUrl?: string) {
		return requestJson<boolean>("/anthropic/key/exists", {}, baseUrl);
	},
	getAnthropicModels(baseUrl?: string) {
		return requestJson<AnthropicModelInfo[]>("/anthropic/models", {}, baseUrl);
	},
	setAnthropicApiKey(api_key: string, baseUrl?: string) {
		return requestJson<boolean>(
			"/anthropic/key",
			{ method: "POST", body: JSON.stringify({ api_key }) },
			baseUrl,
		);
	},
	readFile(path: string, baseUrl?: string) {
		return requestJson<string>(
			"/fs/read",
			{ method: "POST", body: JSON.stringify({ path }) },
			baseUrl,
		);
	},
	writeFile(path: string, content: string, baseUrl?: string) {
		return requestJson<boolean>(
			"/fs/write",
			{ method: "POST", body: JSON.stringify({ path, content }) },
			baseUrl,
		);
	},
	listDirectory(path: string, baseUrl?: string) {
		return requestJson<FileEntry[]>(
			"/fs/list",
			{ method: "POST", body: JSON.stringify({ path }) },
			baseUrl,
		);
	},
	listDirectoryAbsolute(path: string, baseUrl?: string) {
		return requestJson<FileEntry[]>(
			"/io/fs/list/absolute",
			{ method: "POST", body: JSON.stringify({ path }) },
			baseUrl,
		);
	},
	createDirectoryAbsolute(path: string, baseUrl?: string) {
		return requestJson<boolean>(
			"/io/fs/create/absolute",
			{ method: "POST", body: JSON.stringify({ path }) },
			baseUrl,
		);
	},
	getHomeDirectory(baseUrl?: string) {
		return requestJson<string>("/io/fs/home", {}, baseUrl);
	},
	listProjectFiles(baseUrl?: string) {
		return requestJson<string[]>("/io/fs/files", {}, baseUrl);
	},
	searchFiles(query: string, baseUrl?: string) {
		return requestJson<SearchResult[]>(
			"/fs/search",
			{ method: "POST", body: JSON.stringify({ query }) },
			baseUrl,
		);
	},
	execShell(command: string, args: string[], baseUrl?: string) {
		return requestJson<CommandOutput>(
			"/shell/exec",
			{ method: "POST", body: JSON.stringify({ command, args }) },
			baseUrl,
		);
	},
	cancelChat(baseUrl?: string) {
		return requestJson<boolean>("/chat/cancel", { method: "POST" }, baseUrl);
	},
	getWorkItemContent(storyId: string, baseUrl?: string) {
		return requestJson<WorkItemContent>(
			`/work-items/${encodeURIComponent(storyId)}`,
			{},
			baseUrl,
		);
	},
	getTestResults(storyId: string, baseUrl?: string) {
		return requestJson<TestResultsResponse | null>(
			`/work-items/${encodeURIComponent(storyId)}/test-results`,
			{},
			baseUrl,
		);
	},
	getTokenCost(storyId: string, baseUrl?: string) {
		return requestJson<TokenCostResponse>(
			`/work-items/${encodeURIComponent(storyId)}/token-cost`,
			{},
			baseUrl,
		);
	},
	getAllTokenUsage(baseUrl?: string) {
		return requestJson<AllTokenUsageResponse>("/token-usage", {}, baseUrl);
	},
	/** Trigger a server rebuild and restart. */
	rebuildAndRestart() {
		return callMcpTool("rebuild_and_restart", {});
	},
	/** Approve a story in QA, moving it to merge. */
	approveQa(storyId: string) {
		return callMcpTool("approve_qa", { story_id: storyId });
	},
	/** Reject a story in QA, moving it back to current with notes. */
	rejectQa(storyId: string, notes: string) {
		return callMcpTool("reject_qa", { story_id: storyId, notes });
	},
	/** Launch the QA app for a story's worktree. */
	launchQaApp(storyId: string) {
		return callMcpTool("launch_qa_app", { story_id: storyId });
	},
	/** Delete a story from the pipeline, stopping any running agent and removing the worktree. */
	deleteStory(storyId: string) {
		return callMcpTool("delete_story", { story_id: storyId });
	},
	/** Fetch OAuth status from the server. */
	getOAuthStatus() {
		return requestJson<OAuthStatus>("/oauth/status", {}, "");
	},
	/** Execute a bot slash command without LLM invocation. Returns markdown response text. */
	botCommand(command: string, args: string, baseUrl?: string) {
		return requestJson<{ response: string }>(
			"/bot/command",
			{ method: "POST", body: JSON.stringify({ command, args }) },
			baseUrl,
		);
	},
};