/**
 * Ask Mode Extension
 *
 * Read-only mode for safe code analysis.
 * When enabled, only read-only tools are available.
 *
 * Features:
 * - /ask command to toggle
 * - Bash restricted to allowlisted read-only commands
 */

import type { AgentMessage } from "@earendil-works/pi-agent-core";
import type { ExtensionAPI, ExtensionContext } from "@earendil-works/pi-coding-agent";
import { isSafeCommand } from "./utils.js";

// Tools to block in ask mode (file modification tools)
const BLOCKED_TOOLS = ["edit", "write"];

export default function askModeExtension(pi: ExtensionAPI): void {
	let askModeEnabled = false;
	let originalTools: string[] = [];

	// Dynamically get all tools except blocked ones (edit, write)
	function getAskModeTools(): string[] {
		const allTools = pi.getAllTools();
		return allTools
			.filter(t => !BLOCKED_TOOLS.includes(t.name))
			.map(t => t.name);
	}

	// Get default normal mode tools (all available minus blocked)
	function getNormalModeTools(): string[] {
		const allTools = pi.getAllTools();
		return allTools.map(t => t.name);
	}

	function updateStatus(ctx: ExtensionContext): void {
		// Footer status
		if (askModeEnabled) {
			ctx.ui.setStatus("ask-mode", ctx.ui.theme.fg("warning", "❓ ask"));
		} else {
			ctx.ui.setStatus("ask-mode", undefined);
		}

		// Clear widget
		ctx.ui.setWidget("ask-mode", undefined);
	}

	function toggleAskMode(ctx: ExtensionContext): void {
		askModeEnabled = !askModeEnabled;

		if (askModeEnabled) {
			// Save original tools before switching to ask mode
			originalTools = pi.getActiveTools();
			const askModeTools = getAskModeTools();
			pi.setActiveTools(askModeTools);
			ctx.ui.notify(`Ask mode enabled. Tools: ${askModeTools.join(", ")}`);
		} else {
			// Restore original tools (or default to all tools if not set)
			const normalModeTools = originalTools.length > 0 ? originalTools : getNormalModeTools();
			pi.setActiveTools(normalModeTools);
			ctx.ui.notify("Ask mode disabled. Full access restored. All tools available.");
		}
		updateStatus(ctx);
	}

	pi.registerCommand("ask", {
		description: "Toggle ask mode or ask a question in ask mode",
		handler: async (args, ctx) => {
			const question = args.trim();

			if (question) {
				// /ask with a question - enable ask mode and ask the question
				if (!askModeEnabled) {
					// Enable ask mode first
					askModeEnabled = true;
					// Save original tools before switching to ask mode
					originalTools = pi.getActiveTools();
					const askModeTools = getAskModeTools();
					pi.setActiveTools(askModeTools);
					updateStatus(ctx);
					ctx.ui.notify(`Ask mode enabled. Tools: ${askModeTools.join(", ")}`);
				}

				// Send the question to the agent
				pi.sendUserMessage(question);
			} else {
				// /ask without a message - just toggle
				toggleAskMode(ctx);
			}
		},
	});

	// Block destructive bash commands in ask mode
	pi.on("tool_call", async (event) => {
		if (!askModeEnabled || event.toolName !== "bash") return;

		const command = event.input.command as string;
		if (!isSafeCommand(command)) {
			return {
				block: true,
				reason: `Ask mode: command blocked (not allowlisted). Use /ask to disable ask mode first.\nCommand: ${command}`,
			};
		}
	});

	// Filter out stale ask mode context when not in ask mode
	pi.on("context", async (event) => {
		if (askModeEnabled) return;

		return {
			messages: event.messages.filter((m) => {
				const msg = m as AgentMessage & { customType?: string };
				if (msg.customType === "ask-mode-context") return false;
				if (msg.role !== "user") return true;

				const content = msg.content;
				if (typeof content === "string") {
					return !content.includes("[ASK MODE ACTIVE]");
				}
				if (Array.isArray(content)) {
					return !content.some(
						(c) => c.type === "text" && "text" in c && c.text?.includes("[ASK MODE ACTIVE]"),
					);
				}
				return true;
			}),
		};
	});

	// Inject ask mode context before agent starts
	// v0.65.0: before_agent_start returns systemPromptAppend instead of message
	pi.on("before_agent_start", async (_event) => {
		if (!askModeEnabled) return;

		const askModeTools = getAskModeTools();
		const blockedTools = BLOCKED_TOOLS.join(", ");

		const askModeContext = `
[ASK MODE ACTIVE]
You are in ask mode - a read-only Q&A mode for safe code analysis.

Restrictions:
- You can only use: ${askModeTools.join(", ")}
- You CANNOT use: ${blockedTools} (file modifications are disabled)
- Bash is restricted to an allowlist of read-only commands

Answer the user's question. Do NOT attempt to make any changes.`;

		return { systemPromptAppend: askModeContext };
	});
}