import type { ThinkingLevel } from "@mariozechner/pi-agent-core";
import {
	Container,
	getCapabilities,
	type SelectItem,
	SelectList,
	type SettingItem,
	SettingsList,
	Spacer,
	Text,
} from "@mariozechner/pi-tui";
import { getSelectListTheme, getSettingsListTheme, theme } from "../theme/theme.js";
import { DynamicBorder } from "./dynamic-border.js";

const THINKING_DESCRIPTIONS: Record<ThinkingLevel, string> = {
	off: "No reasoning",
	minimal: "Very brief reasoning (~1k tokens)",
	low: "Light reasoning (~2k tokens)",
	medium: "Moderate reasoning (~8k tokens)",
	high: "Deep reasoning (~16k tokens)",
	xhigh: "Maximum reasoning (~32k tokens)",
};

export interface SettingsConfig {
	autoCompact: boolean;
	showImages: boolean;
	autoResizeImages: boolean;
	steeringMode: "all" | "one-at-a-time";
	followUpMode: "all" | "one-at-a-time";
	thinkingLevel: ThinkingLevel;
	availableThinkingLevels: ThinkingLevel[];
	currentTheme: string;
	availableThemes: string[];
	hideThinkingBlock: boolean;
	collapseChangelog: boolean;
}

export interface SettingsCallbacks {
	onAutoCompactChange: (enabled: boolean) => void;
	onShowImagesChange: (enabled: boolean) => void;
	onAutoResizeImagesChange: (enabled: boolean) => void;
	onSteeringModeChange: (mode: "all" | "one-at-a-time") => void;
	onFollowUpModeChange: (mode: "all" | "one-at-a-time") => void;
	onThinkingLevelChange: (level: ThinkingLevel) => void;
	onThemeChange: (theme: string) => void;
	onThemePreview?: (theme: string) => void;
	onHideThinkingBlockChange: (hidden: boolean) => void;
	onCollapseChangelogChange: (collapsed: boolean) => void;
	onCancel: () => void;
}

/**
 * A submenu component for selecting from a list of options.
 */
class SelectSubmenu extends Container {
	private selectList: SelectList;

	constructor(
		title: string,
		description: string,
		options: SelectItem[],
		currentValue: string,
		onSelect: (value: string) => void,
		onCancel: () => void,
		onSelectionChange?: (value: string) => void,
	) {
		super();

		// Title
		this.addChild(new Text(theme.bold(theme.fg("accent", title)), 0, 0));

		// Description
		if (description) {
			this.addChild(new Spacer(1));
			this.addChild(new Text(theme.fg("muted", description), 0, 0));
		}

		// Spacer
		this.addChild(new Spacer(1));

		// Select list
		this.selectList = new SelectList(options, Math.min(options.length, 10), getSelectListTheme());

		// Pre-select current value
		const currentIndex = options.findIndex((o) => o.value === currentValue);
		if (currentIndex !== -1) {
			this.selectList.setSelectedIndex(currentIndex);
		}

		this.selectList.onSelect = (item) => {
			onSelect(item.value);
		};

		this.selectList.onCancel = onCancel;

		if (onSelectionChange) {
			this.selectList.onSelectionChange = (item) => {
				onSelectionChange(item.value);
			};
		}

		this.addChild(this.selectList);

		// Hint
		this.addChild(new Spacer(1));
		this.addChild(new Text(theme.fg("dim", "  Enter to select · Esc to go back"), 0, 0));
	}

	handleInput(data: string): void {
		this.selectList.handleInput(data);
	}
}

/**
 * Main settings selector component.
 */
export class SettingsSelectorComponent extends Container {
	private settingsList: SettingsList;

	constructor(config: SettingsConfig, callbacks: SettingsCallbacks) {
		super();

		const supportsImages = getCapabilities().images;

		const items: SettingItem[] = [
			{
				id: "autocompact",
				label: "Auto-compact",
				description: "Automatically compact context when it gets too large",
				currentValue: config.autoCompact ? "true" : "false",
				values: ["true", "false"],
			},
			{
				id: "steering-mode",
				label: "Steering mode",
				description:
					"Enter while streaming queues steering messages. 'one-at-a-time': deliver one, wait for response. 'all': deliver all at once.",
				currentValue: config.steeringMode,
				values: ["one-at-a-time", "all"],
			},
			{
				id: "follow-up-mode",
				label: "Follow-up mode",
				description:
					"Alt+Enter queues follow-up messages until agent stops. 'one-at-a-time': deliver one, wait for response. 'all': deliver all at once.",
				currentValue: config.followUpMode,
				values: ["one-at-a-time", "all"],
			},
			{
				id: "hide-thinking",
				label: "Hide thinking",
				description: "Hide thinking blocks in assistant responses",
				currentValue: config.hideThinkingBlock ? "true" : "false",
				values: ["true", "false"],
			},
			{
				id: "collapse-changelog",
				label: "Collapse changelog",
				description: "Show condensed changelog after updates",
				currentValue: config.collapseChangelog ? "true" : "false",
				values: ["true", "false"],
			},
			{
				id: "thinking",
				label: "Thinking level",
				description: "Reasoning depth for thinking-capable models",
				currentValue: config.thinkingLevel,
				submenu: (currentValue, done) =>
					new SelectSubmenu(
						"Thinking Level",
						"Select reasoning depth for thinking-capable models",
						config.availableThinkingLevels.map((level) => ({
							value: level,
							label: level,
							description: THINKING_DESCRIPTIONS[level],
						})),
						currentValue,
						(value) => {
							callbacks.onThinkingLevelChange(value as ThinkingLevel);
							done(value);
						},
						() => done(),
					),
			},
			{
				id: "theme",
				label: "Theme",
				description: "Color theme for the interface",
				currentValue: config.currentTheme,
				submenu: (currentValue, done) =>
					new SelectSubmenu(
						"Theme",
						"Select color theme",
						config.availableThemes.map((t) => ({
							value: t,
							label: t,
						})),
						currentValue,
						(value) => {
							callbacks.onThemeChange(value);
							done(value);
						},
						() => {
							// Restore original theme on cancel
							callbacks.onThemePreview?.(currentValue);
							done();
						},
						(value) => {
							// Preview theme on selection change
							callbacks.onThemePreview?.(value);
						},
					),
			},
		];

		// Only show image toggle if terminal supports it
		if (supportsImages) {
			// Insert after autocompact
			items.splice(1, 0, {
				id: "show-images",
				label: "Show images",
				description: "Render images inline in terminal",
				currentValue: config.showImages ? "true" : "false",
				values: ["true", "false"],
			});
		}

		// Image auto-resize toggle (always available, affects both attached and read images)
		items.splice(supportsImages ? 2 : 1, 0, {
			id: "auto-resize-images",
			label: "Auto-resize images",
			description: "Resize large images to 2000x2000 max for better model compatibility",
			currentValue: config.autoResizeImages ? "true" : "false",
			values: ["true", "false"],
		});

		// Add borders
		this.addChild(new DynamicBorder());

		this.settingsList = new SettingsList(
			items,
			10,
			getSettingsListTheme(),
			(id, newValue) => {
				switch (id) {
					case "autocompact":
						callbacks.onAutoCompactChange(newValue === "true");
						break;
					case "show-images":
						callbacks.onShowImagesChange(newValue === "true");
						break;
					case "auto-resize-images":
						callbacks.onAutoResizeImagesChange(newValue === "true");
						break;
					case "steering-mode":
						callbacks.onSteeringModeChange(newValue as "all" | "one-at-a-time");
						break;
					case "follow-up-mode":
						callbacks.onFollowUpModeChange(newValue as "all" | "one-at-a-time");
						break;
					case "hide-thinking":
						callbacks.onHideThinkingBlockChange(newValue === "true");
						break;
					case "collapse-changelog":
						callbacks.onCollapseChangelogChange(newValue === "true");
						break;
				}
			},
			callbacks.onCancel,
		);

		this.addChild(this.settingsList);
		this.addChild(new DynamicBorder());
	}

	getSettingsList(): SettingsList {
		return this.settingsList;
	}
}