/**
 * Chain Clarification TUI Component
 *
 * Shows templates and resolved behaviors for each step in a chain.
 * Supports editing templates, output paths, reads lists, and progress toggle.
 */

import type { Theme } from "@earendil-works/pi-coding-agent";
import type { Component, TUI } from "@earendil-works/pi-tui";

import { matchesKey, truncateToWidth, visibleWidth } from "@earendil-works/pi-tui";
import * as fs from "node:fs";
import * as path from "node:path";

import type { AgentConfig, ChainConfig, ChainStepConfig } from "./agents.js";
import type { ResolvedStepBehavior } from "./settings.js";
import type { TextEditorState } from "./text-editor.js";

import { updateFrontmatterField } from "./agent-serializer.js";
import { serializeChain } from "./chain-serializer.js";
import { getUserAgentsDir } from "./paths.js";
import {
	createEditorState,
	ensureCursorVisible,
	getCursorDisplayPos,
	handleEditorInput,
	renderEditor,
	wrapText,
} from "./text-editor.js";

/** Clarify TUI mode */
export type ClarifyMode = "single" | "parallel" | "chain";

/** Model info for display */
export interface ModelInfo {
	provider: string;
	id: string;
	fullId: string; // "provider/id"
}

/** Modified behavior overrides from TUI editing */
export interface BehaviorOverride {
	output?: string | false;
	reads?: string[] | false;
	progress?: boolean;
	model?: string; // Override agent's default model (format: "provider/id")
	skills?: string[] | false;
}

export interface ChainClarifyResult {
	confirmed: boolean;
	templates: string[];
	/** User-modified behavior overrides per step (undefined = no changes) */
	behaviorOverrides: (BehaviorOverride | undefined)[];
	/** User requested background/async execution */
	runInBackground?: boolean;
}

type EditMode = "template" | "output" | "reads" | "model" | "thinking" | "skills";

/** Valid thinking levels */
const THINKING_LEVELS = ["off", "minimal", "low", "medium", "high", "xhigh"] as const;
type ThinkingLevel = (typeof THINKING_LEVELS)[number];

/**
 * TUI component for chain clarification.
 * Factory signature matches ctx.ui.custom: (tui, theme, kb, done) => Component
 */
export class ChainClarifyComponent implements Component {
	readonly width = 84;

	private selectedStep = 0;
	private editingStep: number | null = null;
	private editMode: EditMode = "template";
	private editState: TextEditorState = createEditorState();

	/** Lines visible in full edit mode */
	private readonly EDIT_VIEWPORT_HEIGHT = 12;

	/** Track user modifications to behaviors (sparse - only stores changes) */
	private behaviorOverrides = new Map<number, BehaviorOverride>();

	/** Model selector state */
	private modelSearchQuery: string = "";
	private modelSelectedIndex: number = 0;
	private filteredModels: ModelInfo[] = [];

	/** Max models visible in selector */
	private readonly MODEL_SELECTOR_HEIGHT = 10;

	/** Thinking level selector state */
	private thinkingSelectedIndex: number = 0;

	/** Skill selector state */
	private skillSearchQuery: string = "";
	private skillSelectedNames = new Set<string>();
	private skillCursorIndex: number = 0;
	private filteredSkills: {
		name: string;
		source: string;
		description?: string;
	}[] = [];
	private saveMessage: { text: string; type: "info" | "error" } | null = null;
	private saveMessageTimer: ReturnType<typeof setTimeout> | null = null;
	private saveChainNameState: TextEditorState = createEditorState();
	private savingChain = false;
	/** Run in background (async) mode */
	private runInBackground = false;

	constructor(
		private tui: TUI,
		private theme: Theme,
		private agentConfigs: AgentConfig[],
		private templates: string[],
		private originalTask: string,
		private chainDir: string | undefined, // Undefined for single/parallel modes
		private resolvedBehaviors: ResolvedStepBehavior[],
		private availableModels: ModelInfo[],
		private availableSkills: {
			name: string;
			source: string;
			description?: string;
		}[],
		private done: (result: ChainClarifyResult) => void,
		private mode: ClarifyMode = "chain", // Mode: 'single', 'parallel', or 'chain'
	) {
		// Initialize filtered models
		this.filteredModels = [...availableModels];
		this.filteredSkills = [...availableSkills];
	}

	// ─────────────────────────────────────────────────────────────────────────────
	// Helper methods for rendering
	// ─────────────────────────────────────────────────────────────────────────────

	/** Pad string to specified visible width */
	private pad(s: string, len: number): string {
		const vis = visibleWidth(s);
		return s + " ".repeat(Math.max(0, len - vis));
	}

	/** Create a row with border characters */
	private row(content: string): string {
		const innerW = this.width - 2;
		return this.theme.fg("border", "│") + this.pad(content, innerW) + this.theme.fg("border", "│");
	}

	/** Render centered header line with border */
	private renderHeader(text: string): string {
		const innerW = this.width - 2;
		const padLen = Math.max(0, innerW - visibleWidth(text));
		const padLeft = Math.floor(padLen / 2);
		const padRight = padLen - padLeft;
		return (
			this.theme.fg("border", "╭" + "─".repeat(padLeft)) +
			this.theme.fg("accent", text) +
			this.theme.fg("border", "─".repeat(padRight) + "╮")
		);
	}

	/** Render centered footer line with border */
	private renderFooter(text: string): string {
		const innerW = this.width - 2;
		const padLen = Math.max(0, innerW - visibleWidth(text));
		const padLeft = Math.floor(padLen / 2);
		const padRight = padLen - padLeft;
		return (
			this.theme.fg("border", "╰" + "─".repeat(padLeft)) +
			this.theme.fg("dim", text) +
			this.theme.fg("border", "─".repeat(padRight) + "╯")
		);
	}

	/** Exit edit mode and reset state */
	private exitEditMode(): void {
		this.editingStep = null;
		this.editState = createEditorState();
		this.tui.requestRender();
	}

	// ─────────────────────────────────────────────────────────────────────────────
	// Full edit mode methods
	// ─────────────────────────────────────────────────────────────────────────────

	/** Render the full-edit takeover view */
	private renderFullEditMode(): string[] {
		const innerW = this.width - 2;
		const textWidth = innerW - 2; // 1 char padding on each side
		const lines: string[] = [];

		const { lines: wrapped, starts } = wrapText(this.editState.buffer, textWidth);
		const cursorPos = getCursorDisplayPos(this.editState.cursor, starts);
		this.editState = {
			...this.editState,
			viewportOffset: ensureCursorVisible(cursorPos.line, this.EDIT_VIEWPORT_HEIGHT, this.editState.viewportOffset),
		};

		// Header (truncate agent name to prevent overflow)
		const fieldName = this.editMode === "template" ? "task" : this.editMode;
		const rawAgentName = this.agentConfigs[this.editingStep!]?.name ?? "unknown";
		const maxAgentLen = innerW - 30; // Reserve space for " Editing X (Step/Task N: ) "
		const agentName = rawAgentName.length > maxAgentLen ? `${rawAgentName.slice(0, maxAgentLen - 1)}…` : rawAgentName;
		// Use mode-appropriate terminology
		const stepLabel =
			this.mode === "single"
				? agentName
				: this.mode === "parallel"
					? `Task ${this.editingStep! + 1}: ${agentName}`
					: `Step ${this.editingStep! + 1}: ${agentName}`;
		const headerText = ` Editing ${fieldName} (${stepLabel}) `;
		lines.push(this.renderHeader(headerText));
		lines.push(this.row(""));

		const editorLines = renderEditor(this.editState, textWidth, this.EDIT_VIEWPORT_HEIGHT);
		for (const line of editorLines) {
			lines.push(this.row(` ${line}`));
		}

		// Scroll indicators
		const linesBelow = wrapped.length - this.editState.viewportOffset - this.EDIT_VIEWPORT_HEIGHT;
		const hasMore = linesBelow > 0;
		const hasLess = this.editState.viewportOffset > 0;
		let scrollInfo = "";
		if (hasLess) {
			scrollInfo += "↑";
		}
		if (hasMore) {
			scrollInfo += `↓ ${linesBelow}+`;
		}

		lines.push(this.row(""));

		// Footer with scroll indicators if applicable
		const footerText = scrollInfo
			? ` [Esc] Done • [Ctrl+C] Discard • ${scrollInfo} `
			: " [Esc] Done • [Ctrl+C] Discard ";
		lines.push(this.renderFooter(footerText));

		return lines;
	}

	// ─────────────────────────────────────────────────────────────────────────────
	// Behavior helpers
	// ─────────────────────────────────────────────────────────────────────────────

	/** Get effective behavior for a step (with user overrides applied) */
	private getEffectiveBehavior(stepIndex: number): ResolvedStepBehavior {
		const base = this.resolvedBehaviors[stepIndex]!;
		const override = this.behaviorOverrides.get(stepIndex);
		if (!override) {
			return base;
		}

		return {
			model: override.model !== undefined ? override.model : base.model,
			output: override.output !== undefined ? override.output : base.output,
			progress: override.progress !== undefined ? override.progress : base.progress,
			reads: override.reads !== undefined ? override.reads : base.reads,
			skills: override.skills !== undefined ? override.skills : base.skills,
		};
	}

	/** Get the effective model for a step (override or agent default) */
	private getEffectiveModel(stepIndex: number): string {
		const override = this.behaviorOverrides.get(stepIndex);
		if (override?.model) {
			return override.model;
		} // Override is already in provider/model format

		const baseModel = this.resolvedBehaviors[stepIndex]?.model;
		if (baseModel) {
			return this.resolveModelFullId(baseModel);
		}
		return "default";
	}

	/** Resolve a model name to its full provider/model format */
	private resolveModelFullId(modelName: string): string {
		// If already in provider/model format, return as-is
		if (modelName.includes("/")) {
			return modelName;
		}

		// Handle thinking level suffixes (e.g., "claude-sonnet-4-5:high")
		// Strip the suffix for lookup, then add it back
		const colonIdx = modelName.lastIndexOf(":");
		const baseModel = colonIdx !== -1 ? modelName.substring(0, colonIdx) : modelName;
		const thinkingSuffix = colonIdx !== -1 ? modelName.substring(colonIdx) : "";

		// Look up base model in available models to find provider
		const match = this.availableModels.find((m) => m.id === baseModel);
		if (match) {
			return thinkingSuffix ? `${match.fullId}${thinkingSuffix}` : match.fullId;
		}

		// Fallback to just the model name if not found
		return modelName;
	}

	/** Update a behavior override for a step */
	private updateBehavior(
		stepIndex: number,
		field: keyof BehaviorOverride,
		value: string | boolean | string[] | false,
	): void {
		const existing = this.behaviorOverrides.get(stepIndex) ?? {};
		this.behaviorOverrides.set(stepIndex, { ...existing, [field]: value });
	}

	private buildChainConfig(name: string): ChainConfig {
		const steps: ChainStepConfig[] = [];
		for (let i = 0; i < this.agentConfigs.length; i++) {
			const agent = this.agentConfigs[i]!;
			const behavior = this.getEffectiveBehavior(i);
			const override = this.behaviorOverrides.get(i);
			const template = this.templates[i] ?? "";
			const step: ChainStepConfig = { agent: agent.name, task: template };
			if (override?.output !== undefined) {
				step.output = behavior.output;
			}
			if (override?.reads !== undefined) {
				step.reads = behavior.reads;
			}
			if (override?.model !== undefined) {
				step.model = behavior.model;
			}
			if (override?.skills !== undefined) {
				step.skills = behavior.skills;
			}
			if (override?.progress !== undefined) {
				step.progress = behavior.progress;
			}
			steps.push(step);
		}
		return {
			description: `Chain: ${steps.map((s) => s.agent).join(" → ")}`,
			filePath: "",
			name,
			source: "user",
			steps,
		};
	}

	private enterSaveChainName(): void {
		this.savingChain = true;
		this.saveChainNameState = createEditorState();
		this.tui.requestRender();
	}

	private handleSaveChainNameInput(data: string): void {
		if (matchesKey(data, "tab")) {
			return;
		}
		const innerW = this.width - 2;
		const boxInnerWidth = Math.max(10, innerW - 4);
		const nextState = handleEditorInput(this.saveChainNameState, data, boxInnerWidth);
		if (nextState) {
			this.saveChainNameState = nextState;
			this.tui.requestRender();
			return;
		}
		if (matchesKey(data, "escape") || matchesKey(data, "ctrl+c")) {
			this.savingChain = false;
			this.saveChainNameState = createEditorState();
			this.tui.requestRender();
			return;
		}
		if (matchesKey(data, "return")) {
			const name = this.saveChainNameState.buffer.trim();
			if (!name) {
				this.showSaveMessage("Name is required", "error");
				this.savingChain = false;
				this.saveChainNameState = createEditorState();
				return;
			}
			try {
				const dir = getUserAgentsDir();
				fs.mkdirSync(dir, { recursive: true });
				const filePath = path.join(dir, `${name}.chain.md`);
				const config = this.buildChainConfig(name);
				config.filePath = filePath;
				fs.writeFileSync(filePath, serializeChain(config), "utf8");
				this.showSaveMessage(`Saved ${name}.chain.md`, "info");
			} catch (error) {
				this.showSaveMessage(error instanceof Error ? error.message : "Failed to save chain", "error");
			}
			this.savingChain = false;
			this.saveChainNameState = createEditorState();
		}
	}

	private showSaveMessage(text: string, type: "info" | "error"): void {
		this.saveMessage = { text, type };
		if (this.saveMessageTimer) {
			clearTimeout(this.saveMessageTimer);
		}
		this.saveMessageTimer = setTimeout(() => {
			this.saveMessage = null;
			this.saveMessageTimer = null;
			this.tui.requestRender();
		}, 2000);
		this.tui.requestRender();
	}

	private arraysEqual(a: string[] | false, b: string[] | false): boolean {
		if (a === b) {
			return true;
		}
		if (a === false || b === false) {
			return false;
		}
		if (a.length !== b.length) {
			return false;
		}
		for (let i = 0; i < a.length; i++) {
			if (a[i] !== b[i]) {
				return false;
			}
		}
		return true;
	}

	private saveOverridesToAgent(): void {
		const stepIndex = this.selectedStep;
		const agent = this.agentConfigs[stepIndex];
		if (!agent?.filePath) {
			this.showSaveMessage("Agent file not found", "error");
			return;
		}

		const override = this.behaviorOverrides.get(stepIndex);
		if (!override) {
			this.showSaveMessage("No changes to save", "info");
			return;
		}

		const base = this.resolvedBehaviors[stepIndex]!;
		const updates: { field: string; value: string | undefined }[] = [];

		if (override.output !== undefined && override.output !== base.output) {
			updates.push({
				field: "output",
				value: override.output === false ? undefined : override.output,
			});
		}

		if (override.reads !== undefined && !this.arraysEqual(override.reads, base.reads)) {
			updates.push({
				field: "defaultReads",
				value: override.reads === false ? undefined : override.reads.join(", "),
			});
		}

		if (override.progress !== undefined && override.progress !== base.progress) {
			updates.push({
				field: "defaultProgress",
				value: override.progress ? "true" : undefined,
			});
		}

		if (override.skills !== undefined && !this.arraysEqual(override.skills, base.skills)) {
			updates.push({
				field: "skills",
				value: override.skills === false || override.skills.length === 0 ? undefined : override.skills.join(", "),
			});
		}

		if (override.model !== undefined) {
			const baseModel = agent.model ? this.resolveModelFullId(agent.model) : undefined;
			if (override.model !== baseModel) {
				updates.push({ field: "model", value: override.model });
			}
		}

		if (updates.length === 0) {
			this.showSaveMessage("No changes to save", "info");
			return;
		}

		try {
			for (const update of updates) {
				updateFrontmatterField(agent.filePath, update.field, update.value);
			}
			this.showSaveMessage("Saved agent settings", "info");
		} catch (error) {
			this.showSaveMessage(error instanceof Error ? error.message : "Failed to save agent settings", "error");
		}
	}

	handleInput(data: string): void {
		if (this.savingChain) {
			this.handleSaveChainNameInput(data);
			return;
		}

		if (this.editingStep !== null) {
			if (this.editMode === "model") {
				this.handleModelSelectorInput(data);
			} else if (this.editMode === "thinking") {
				this.handleThinkingSelectorInput(data);
			} else if (this.editMode === "skills") {
				this.handleSkillSelectorInput(data);
			} else {
				this.handleEditInput(data);
			}
			return;
		}

		// Navigation mode
		if (matchesKey(data, "escape") || matchesKey(data, "ctrl+c")) {
			this.done({ behaviorOverrides: [], confirmed: false, templates: [] });
			return;
		}

		if (matchesKey(data, "return")) {
			// Build behavior overrides array
			const overrides: (BehaviorOverride | undefined)[] = [];
			for (let i = 0; i < this.agentConfigs.length; i++) {
				overrides.push(this.behaviorOverrides.get(i));
			}
			this.done({
				behaviorOverrides: overrides,
				confirmed: true,
				runInBackground: this.runInBackground,
				templates: this.templates,
			});
			return;
		}

		if (matchesKey(data, "up")) {
			this.selectedStep = Math.max(0, this.selectedStep - 1);
			this.tui.requestRender();
			return;
		}

		if (matchesKey(data, "down")) {
			const maxStep = Math.max(0, this.agentConfigs.length - 1);
			this.selectedStep = Math.min(maxStep, this.selectedStep + 1);
			this.tui.requestRender();
			return;
		}

		// 'e' to edit template (all modes)
		if (data === "e") {
			this.enterEditMode("template");
			return;
		}

		// 'm' to select model (all modes)
		if (data === "m") {
			this.enterModelSelector();
			return;
		}

		// 't' to select thinking level (all modes)
		if (data === "t") {
			this.enterThinkingSelector();
			return;
		}

		// 's' to select skills (all modes)
		if (data === "s") {
			this.editingStep = this.selectedStep;
			this.editMode = "skills";
			this.skillSearchQuery = "";
			this.skillCursorIndex = 0;
			this.filteredSkills = [...this.availableSkills];
			const current = this.getEffectiveBehavior(this.selectedStep).skills;
			this.skillSelectedNames.clear();
			if (current !== false && current.length > 0) {
				current.forEach((skillName) => this.skillSelectedNames.add(skillName));
			}
			this.tui.requestRender();
			return;
		}

		// 'w' to edit writes (single and chain only - not parallel)
		if (data === "w" && this.mode !== "parallel") {
			this.enterEditMode("output");
			return;
		}

		// 'r' to edit reads (chain only)
		if (data === "r" && this.mode === "chain") {
			this.enterEditMode("reads");
			return;
		}

		// 'p' to toggle progress for ALL steps (chain only - chains share a single progress.md)
		if (data === "p" && this.mode === "chain") {
			// Check if any step has progress enabled
			const anyEnabled = this.agentConfigs.some((_, i) => this.getEffectiveBehavior(i).progress);
			// Toggle all steps to the opposite state
			const newState = !anyEnabled;
			for (let i = 0; i < this.agentConfigs.length; i++) {
				this.updateBehavior(i, "progress", newState);
			}
			this.tui.requestRender();
			return;
		}

		// 'b' to toggle background/async execution (all modes)
		if (data === "b") {
			this.runInBackground = !this.runInBackground;
			this.tui.requestRender();
			return;
		}

		if (data === "S") {
			this.saveOverridesToAgent();
			return;
		}

		if (data === "W" && this.mode === "chain") {
			this.enterSaveChainName();
			return;
		}
	}

	private enterEditMode(mode: EditMode): void {
		this.editingStep = this.selectedStep;
		this.editMode = mode;
		let buffer = "";

		if (mode === "template") {
			const template = this.templates[this.selectedStep] ?? "";
			buffer = template.split("\n")[0] ?? "";
		} else if (mode === "output") {
			const behavior = this.getEffectiveBehavior(this.selectedStep);
			buffer = behavior.output === false ? "" : behavior.output || "";
		} else if (mode === "reads") {
			const behavior = this.getEffectiveBehavior(this.selectedStep);
			buffer = behavior.reads === false ? "" : behavior.reads?.join(", ") || "";
		}

		this.editState = createEditorState(buffer);
		this.tui.requestRender();
	}

	/** Enter model selector mode */
	private enterModelSelector(): void {
		this.editingStep = this.selectedStep;
		this.editMode = "model";
		this.modelSearchQuery = "";
		this.modelSelectedIndex = 0;
		this.filteredModels = [...this.availableModels];

		// Pre-select current model if it exists in the list
		const currentModel = this.getEffectiveModel(this.selectedStep);
		const currentIndex = this.filteredModels.findIndex((m) => m.fullId === currentModel || m.id === currentModel);
		if (currentIndex !== -1) {
			this.modelSelectedIndex = currentIndex;
		}

		this.tui.requestRender();
	}

	/** Filter models based on search query (fuzzy match) */
	private filterModels(): void {
		const query = this.modelSearchQuery.toLowerCase();
		if (!query) {
			this.filteredModels = [...this.availableModels];
		} else {
			this.filteredModels = this.availableModels.filter(
				(m) =>
					m.fullId.toLowerCase().includes(query) ||
					m.id.toLowerCase().includes(query) ||
					m.provider.toLowerCase().includes(query),
			);
		}
		// Clamp selected index
		this.modelSelectedIndex = Math.min(this.modelSelectedIndex, Math.max(0, this.filteredModels.length - 1));
	}

	/** Handle input in model selector mode */
	private handleModelSelectorInput(data: string): void {
		// Escape or Ctrl+C - cancel and exit
		if (matchesKey(data, "escape") || matchesKey(data, "ctrl+c")) {
			this.exitEditMode();
			return;
		}

		// Enter - select current model
		if (matchesKey(data, "return")) {
			const selected = this.filteredModels[this.modelSelectedIndex];
			if (selected) {
				this.updateBehavior(this.editingStep!, "model", selected.fullId);
			}
			this.exitEditMode();
			return;
		}

		// Up arrow - move selection up
		if (matchesKey(data, "up")) {
			if (this.filteredModels.length > 0) {
				this.modelSelectedIndex =
					this.modelSelectedIndex === 0 ? this.filteredModels.length - 1 : this.modelSelectedIndex - 1;
			}
			this.tui.requestRender();
			return;
		}

		// Down arrow - move selection down
		if (matchesKey(data, "down")) {
			if (this.filteredModels.length > 0) {
				this.modelSelectedIndex =
					this.modelSelectedIndex === this.filteredModels.length - 1 ? 0 : this.modelSelectedIndex + 1;
			}
			this.tui.requestRender();
			return;
		}

		// Backspace - delete last character from search
		if (matchesKey(data, "backspace")) {
			if (this.modelSearchQuery.length > 0) {
				this.modelSearchQuery = this.modelSearchQuery.slice(0, -1);
				this.filterModels();
			}
			this.tui.requestRender();
			return;
		}

		// Printable character - add to search query
		if (data.length === 1 && data.codePointAt(0) >= 32) {
			this.modelSearchQuery += data;
			this.filterModels();
			this.tui.requestRender();
			return;
		}
	}

	/** Enter thinking level selector mode */
	private enterThinkingSelector(): void {
		this.editingStep = this.selectedStep;
		this.editMode = "thinking";

		// Pre-select current thinking level if set
		const currentModel = this.getEffectiveModel(this.selectedStep);
		const colonIdx = currentModel.lastIndexOf(":");
		if (colonIdx !== -1) {
			const suffix = currentModel.substring(colonIdx + 1);
			const levelIdx = THINKING_LEVELS.indexOf(suffix as ThinkingLevel);
			this.thinkingSelectedIndex = Math.max(levelIdx, 0);
		} else {
			this.thinkingSelectedIndex = 0; // Default to "off"
		}

		this.tui.requestRender();
	}

	/** Handle input in thinking level selector mode */
	private handleThinkingSelectorInput(data: string): void {
		// Escape or Ctrl+C - cancel and exit
		if (matchesKey(data, "escape") || matchesKey(data, "ctrl+c")) {
			this.exitEditMode();
			return;
		}

		// Enter - select current thinking level
		if (matchesKey(data, "return")) {
			const selectedLevel = THINKING_LEVELS[this.thinkingSelectedIndex];
			this.applyThinkingLevel(selectedLevel);
			this.exitEditMode();
			return;
		}

		// Up arrow - move selection up
		if (matchesKey(data, "up")) {
			this.thinkingSelectedIndex =
				this.thinkingSelectedIndex === 0 ? THINKING_LEVELS.length - 1 : this.thinkingSelectedIndex - 1;
			this.tui.requestRender();
			return;
		}

		// Down arrow - move selection down
		if (matchesKey(data, "down")) {
			this.thinkingSelectedIndex =
				this.thinkingSelectedIndex === THINKING_LEVELS.length - 1 ? 0 : this.thinkingSelectedIndex + 1;
			this.tui.requestRender();
			return;
		}
	}

	/** Apply thinking level to the current step's model */
	private applyThinkingLevel(level: ThinkingLevel): void {
		const stepIndex = this.editingStep!;
		const currentModel = this.getEffectiveModel(stepIndex);

		// Strip any existing thinking level suffix
		const colonIdx = currentModel.lastIndexOf(":");
		let baseModel = currentModel;
		if (colonIdx !== -1) {
			const suffix = currentModel.substring(colonIdx + 1);
			if (THINKING_LEVELS.includes(suffix as ThinkingLevel)) {
				baseModel = currentModel.substring(0, colonIdx);
			}
		}

		// Apply new thinking level (don't add suffix for "off")
		const newModel = level === "off" ? baseModel : `${baseModel}:${level}`;
		this.updateBehavior(stepIndex, "model", newModel);
	}

	private filterSkills(): void {
		const query = this.skillSearchQuery.toLowerCase();
		if (!query) {
			this.filteredSkills = [...this.availableSkills];
		} else {
			this.filteredSkills = this.availableSkills.filter(
				(s) => s.name.toLowerCase().includes(query) || (s.description?.toLowerCase().includes(query) ?? false),
			);
		}
		this.skillCursorIndex = Math.min(this.skillCursorIndex, Math.max(0, this.filteredSkills.length - 1));
	}

	private handleSkillSelectorInput(data: string): void {
		if (matchesKey(data, "escape") || matchesKey(data, "ctrl+c")) {
			this.exitEditMode();
			return;
		}

		if (matchesKey(data, "return")) {
			const selected = [...this.skillSelectedNames];
			this.updateBehavior(this.editingStep!, "skills", selected);
			this.exitEditMode();
			return;
		}

		if (data === " ") {
			if (this.filteredSkills.length > 0) {
				const skill = this.filteredSkills[this.skillCursorIndex];
				if (skill) {
					if (this.skillSelectedNames.has(skill.name)) {
						this.skillSelectedNames.delete(skill.name);
					} else {
						this.skillSelectedNames.add(skill.name);
					}
				}
			}
			this.tui.requestRender();
			return;
		}

		if (matchesKey(data, "up")) {
			if (this.filteredSkills.length > 0) {
				this.skillCursorIndex =
					this.skillCursorIndex === 0 ? this.filteredSkills.length - 1 : this.skillCursorIndex - 1;
			}
			this.tui.requestRender();
			return;
		}

		if (matchesKey(data, "down")) {
			if (this.filteredSkills.length > 0) {
				this.skillCursorIndex =
					this.skillCursorIndex === this.filteredSkills.length - 1 ? 0 : this.skillCursorIndex + 1;
			}
			this.tui.requestRender();
			return;
		}

		if (matchesKey(data, "backspace")) {
			if (this.skillSearchQuery.length > 0) {
				this.skillSearchQuery = this.skillSearchQuery.slice(0, -1);
				this.filterSkills();
			}
			this.tui.requestRender();
			return;
		}

		if (data.length === 1 && data.codePointAt(0) >= 32) {
			this.skillSearchQuery += data;
			this.filterSkills();
			this.tui.requestRender();
			return;
		}
	}

	private handleEditInput(data: string): void {
		const textWidth = this.width - 4; // Must match render: innerW - 2 = (width - 2) - 2
		if (matchesKey(data, "shift+up") || matchesKey(data, "pageup")) {
			const { lines: wrapped, starts } = wrapText(this.editState.buffer, textWidth);
			const cursorPos = getCursorDisplayPos(this.editState.cursor, starts);
			const targetLine = Math.max(0, cursorPos.line - this.EDIT_VIEWPORT_HEIGHT);
			const targetCol = Math.min(cursorPos.col, wrapped[targetLine]?.length ?? 0);
			this.editState = {
				...this.editState,
				cursor: starts[targetLine] + targetCol,
			};
			this.tui.requestRender();
			return;
		}

		if (matchesKey(data, "shift+down") || matchesKey(data, "pagedown")) {
			const { lines: wrapped, starts } = wrapText(this.editState.buffer, textWidth);
			const cursorPos = getCursorDisplayPos(this.editState.cursor, starts);
			const targetLine = Math.min(wrapped.length - 1, cursorPos.line + this.EDIT_VIEWPORT_HEIGHT);
			const targetCol = Math.min(cursorPos.col, wrapped[targetLine]?.length ?? 0);
			this.editState = {
				...this.editState,
				cursor: starts[targetLine] + targetCol,
			};
			this.tui.requestRender();
			return;
		}

		if (matchesKey(data, "tab")) {
			return;
		}

		const nextState = handleEditorInput(this.editState, data, textWidth);
		if (nextState) {
			this.editState = nextState;
			this.tui.requestRender();
			return;
		}

		if (matchesKey(data, "escape")) {
			this.saveEdit();
			this.exitEditMode();
			return;
		}

		if (matchesKey(data, "ctrl+c")) {
			this.exitEditMode();
			return;
		}
	}

	private saveEdit(): void {
		const stepIndex = this.editingStep!;

		if (this.editMode === "template") {
			// For template, preserve other lines if they existed
			const original = this.templates[stepIndex] ?? "";
			const originalLines = original.split("\n");
			originalLines[0] = this.editState.buffer;
			this.templates[stepIndex] = originalLines.join("\n");
		} else if (this.editMode === "output") {
			// Capture OLD output before updating (for downstream propagation)
			const oldBehavior = this.getEffectiveBehavior(stepIndex);
			const oldOutput = typeof oldBehavior.output === "string" ? oldBehavior.output : null;

			// Empty string or whitespace means disable output
			const trimmed = this.editState.buffer.trim();
			const newOutput = trimmed === "" ? false : trimmed;
			this.updateBehavior(stepIndex, "output", newOutput);

			// Propagate output filename change to downstream steps' reads
			if (oldOutput && typeof newOutput === "string" && oldOutput !== newOutput) {
				this.propagateOutputChange(stepIndex, oldOutput, newOutput);
			}
		} else if (this.editMode === "reads") {
			// Parse comma-separated list, empty means disable reads
			const trimmed = this.editState.buffer.trim();
			if (trimmed === "") {
				this.updateBehavior(stepIndex, "reads", false);
			} else {
				const files = trimmed
					.split(",")
					.map((f) => f.trim())
					.filter((f) => f !== "");
				this.updateBehavior(stepIndex, "reads", files.length > 0 ? files : false);
			}
		}
	}

	/**
	 * When a step's output filename changes, update downstream steps that read from it.
	 * This maintains the chain dependency automatically.
	 */
	private propagateOutputChange(changedStepIndex: number, oldOutput: string, newOutput: string): void {
		// Check all downstream steps (steps that come after the changed step)
		for (let i = changedStepIndex + 1; i < this.agentConfigs.length; i++) {
			const behavior = this.getEffectiveBehavior(i);

			// Skip if reads is disabled or empty
			if (behavior.reads === false || !behavior.reads || behavior.reads.length === 0) {
				continue;
			}

			// Check if this step reads the old output file
			const readsArray = behavior.reads;
			const oldIndex = readsArray.indexOf(oldOutput);

			if (oldIndex !== -1) {
				// Replace old filename with new filename in reads
				const newReads = [...readsArray];
				newReads[oldIndex] = newOutput;
				this.updateBehavior(i, "reads", newReads);
			}
		}
	}

	private renderSaveChainName(): string[] {
		const lines: string[] = [];
		const innerW = this.width - 2;
		const boxInnerWidth = Math.max(10, innerW - 4);
		lines.push(this.renderHeader(" Save Chain "));
		lines.push(this.row(""));
		lines.push(this.row(` ${this.theme.fg("dim", "Name:")}`));
		const top = `┌${"─".repeat(boxInnerWidth)}┐`;
		const bottom = `└${"─".repeat(boxInnerWidth)}┘`;
		lines.push(this.row(` ${top}`));
		const editorState = { ...this.saveChainNameState };
		const wrapped = wrapText(editorState.buffer, boxInnerWidth);
		const cursorPos = getCursorDisplayPos(editorState.cursor, wrapped.starts);
		editorState.viewportOffset = ensureCursorVisible(cursorPos.line, 1, editorState.viewportOffset);
		const editorLine = renderEditor(editorState, boxInnerWidth, 1)[0] ?? "";
		lines.push(this.row(` │${this.pad(editorLine, boxInnerWidth)}│`));
		lines.push(this.row(` ${bottom}`));
		lines.push(this.row(""));
		lines.push(this.renderFooter(" [Enter] Save • [Esc] Cancel "));
		return lines;
	}

	render(_width: number): string[] {
		if (this.savingChain) {
			return this.renderSaveChainName();
		}
		if (this.editingStep !== null) {
			if (this.editMode === "model") {
				return this.renderModelSelector();
			}
			if (this.editMode === "thinking") {
				return this.renderThinkingSelector();
			}
			if (this.editMode === "skills") {
				return this.renderSkillSelector();
			}
			return this.renderFullEditMode();
		}
		// Mode-based navigation rendering
		switch (this.mode) {
			case "single": {
				return this.renderSingleMode();
			}
			case "parallel": {
				return this.renderParallelMode();
			}
			case "chain": {
				return this.renderChainMode();
			}
		}
	}

	/** Render the model selector view */
	private renderModelSelector(): string[] {
		const th = this.theme;
		const lines: string[] = [];

		// Header (mode-aware terminology)
		const agentName = this.agentConfigs[this.editingStep!]?.name ?? "unknown";
		const stepLabel =
			this.mode === "single"
				? agentName
				: this.mode === "parallel"
					? `Task ${this.editingStep! + 1}: ${agentName}`
					: `Step ${this.editingStep! + 1}: ${agentName}`;
		const headerText = ` Select Model (${stepLabel}) `;
		lines.push(this.renderHeader(headerText));
		lines.push(this.row(""));

		// Search input
		const searchPrefix = th.fg("dim", "Search: ");
		const cursor = "\x1B[7m \x1B[27m"; // Reverse video space for cursor
		const searchDisplay = this.modelSearchQuery + cursor;
		lines.push(this.row(` ${searchPrefix}${searchDisplay}`));
		lines.push(this.row(""));

		// Current model info
		const currentModel = this.getEffectiveModel(this.editingStep!);
		const currentLabel = th.fg("dim", "Current: ");
		lines.push(this.row(` ${currentLabel}${th.fg("warning", currentModel)}`));
		lines.push(this.row(""));

		// Model list with scroll
		if (this.filteredModels.length === 0) {
			lines.push(this.row(` ${th.fg("dim", "No matching models")}`));
		} else {
			// Calculate visible range (scroll to keep selection visible)
			const maxVisible = this.MODEL_SELECTOR_HEIGHT;
			let startIdx = 0;

			// Keep selection centered if possible
			if (this.filteredModels.length > maxVisible) {
				startIdx = Math.max(0, this.modelSelectedIndex - Math.floor(maxVisible / 2));
				startIdx = Math.min(startIdx, this.filteredModels.length - maxVisible);
			}

			const endIdx = Math.min(startIdx + maxVisible, this.filteredModels.length);

			// Show scroll indicator if needed
			if (startIdx > 0) {
				lines.push(this.row(` ${th.fg("dim", `  ↑ ${startIdx} more`)}`));
			}

			for (let i = startIdx; i < endIdx; i++) {
				const model = this.filteredModels[i]!;
				const isSelected = i === this.modelSelectedIndex;
				const isCurrent = model.fullId === currentModel || model.id === currentModel;

				const prefix = isSelected ? th.fg("accent", "→ ") : "  ";
				const modelText = isSelected ? th.fg("accent", model.id) : model.id;
				const providerBadge = th.fg("dim", ` [${model.provider}]`);
				const currentBadge = isCurrent ? th.fg("success", " +") : "";

				lines.push(this.row(` ${prefix}${modelText}${providerBadge}${currentBadge}`));
			}

			// Show scroll indicator if needed
			const remaining = this.filteredModels.length - endIdx;
			if (remaining > 0) {
				lines.push(this.row(` ${th.fg("dim", `  ↓ ${remaining} more`)}`));
			}
		}

		// Pad to consistent height
		const contentLines = lines.length;
		const targetHeight = 18; // Consistent height
		for (let i = contentLines; i < targetHeight; i++) {
			lines.push(this.row(""));
		}

		// Footer
		const footerText = " [Enter] Select • [Esc] Cancel • Type to search ";
		lines.push(this.renderFooter(footerText));

		return lines;
	}

	/** Render the thinking level selector view */
	private renderThinkingSelector(): string[] {
		const th = this.theme;
		const lines: string[] = [];

		// Header (mode-aware terminology)
		const agentName = this.agentConfigs[this.editingStep!]?.name ?? "unknown";
		const stepLabel =
			this.mode === "single"
				? agentName
				: this.mode === "parallel"
					? `Task ${this.editingStep! + 1}: ${agentName}`
					: `Step ${this.editingStep! + 1}: ${agentName}`;
		const headerText = ` Thinking Level (${stepLabel}) `;
		lines.push(this.renderHeader(headerText));
		lines.push(this.row(""));

		// Current model info
		const currentModel = this.getEffectiveModel(this.editingStep!);
		const currentLabel = th.fg("dim", "Model: ");
		lines.push(this.row(` ${currentLabel}${th.fg("accent", currentModel)}`));
		lines.push(this.row(""));

		// Description
		lines.push(this.row(` ${th.fg("dim", "Select thinking level (extended thinking budget):")}`));
		lines.push(this.row(""));

		// Thinking level options
		const levelDescriptions: Record<ThinkingLevel, string> = {
			high: "Deep reasoning",
			low: "Light reasoning",
			medium: "Moderate reasoning",
			minimal: "Brief reasoning",
			off: "No extended thinking",
			xhigh: "Maximum reasoning (ultrathink)",
		};

		for (let i = 0; i < THINKING_LEVELS.length; i++) {
			const level = THINKING_LEVELS[i];
			const isSelected = i === this.thinkingSelectedIndex;
			const prefix = isSelected ? th.fg("accent", "→ ") : "  ";
			const levelText = isSelected ? th.fg("accent", level) : level;
			const desc = th.fg("dim", ` - ${levelDescriptions[level]}`);
			lines.push(this.row(` ${prefix}${levelText}${desc}`));
		}

		// Pad to consistent height
		const contentLines = lines.length;
		const targetHeight = 16;
		for (let i = contentLines; i < targetHeight; i++) {
			lines.push(this.row(""));
		}

		// Footer
		const footerText = " [Enter] Select • [Esc] Cancel • ↑↓ Navigate ";
		lines.push(this.renderFooter(footerText));

		return lines;
	}

	private renderSkillSelector(): string[] {
		const innerW = this.width - 2;
		const th = this.theme;
		const lines: string[] = [];

		const agentName = this.agentConfigs[this.editingStep!]?.name ?? "unknown";
		const stepLabel =
			this.mode === "single"
				? agentName
				: this.mode === "parallel"
					? `Task ${this.editingStep! + 1}: ${agentName}`
					: `Step ${this.editingStep! + 1}: ${agentName}`;
		lines.push(this.renderHeader(` Select Skills (${stepLabel}) `));
		lines.push(this.row(""));

		const cursor = "\x1B[7m \x1B[27m";
		lines.push(this.row(` ${th.fg("dim", "Search: ")}${this.skillSearchQuery}${cursor}`));
		lines.push(this.row(""));

		const selected = [...this.skillSelectedNames].join(", ") || th.fg("dim", "(none)");
		lines.push(this.row(` ${th.fg("dim", "Selected: ")}${truncateToWidth(selected, innerW - 12)}`));
		lines.push(this.row(""));

		const selectorHeight = 10;
		if (this.filteredSkills.length === 0) {
			lines.push(this.row(` ${th.fg("dim", "No matching skills")}`));
		} else {
			let startIdx = 0;
			if (this.filteredSkills.length > selectorHeight) {
				startIdx = Math.max(0, this.skillCursorIndex - Math.floor(selectorHeight / 2));
				startIdx = Math.min(startIdx, this.filteredSkills.length - selectorHeight);
			}
			const endIdx = Math.min(startIdx + selectorHeight, this.filteredSkills.length);

			if (startIdx > 0) {
				lines.push(this.row(` ${th.fg("dim", `  ↑ ${startIdx} more`)}`));
			}

			for (let i = startIdx; i < endIdx; i++) {
				const skill = this.filteredSkills[i]!;
				const isCursor = i === this.skillCursorIndex;
				const isSelected = this.skillSelectedNames.has(skill.name);

				const prefix = isCursor ? th.fg("accent", "→ ") : "  ";
				const checkbox = isSelected ? th.fg("success", "[x]") : "[ ]";
				const nameText = isCursor ? th.fg("accent", skill.name) : skill.name;
				const sourceBadge = th.fg("dim", ` [${skill.source}]`);
				const desc = skill.description ? th.fg("dim", ` - ${truncateToWidth(skill.description, 25)}`) : "";

				lines.push(this.row(` ${prefix}${checkbox} ${nameText}${sourceBadge}${desc}`));
			}

			const remaining = this.filteredSkills.length - endIdx;
			if (remaining > 0) {
				lines.push(this.row(` ${th.fg("dim", `  ↓ ${remaining} more`)}`));
			}
		}

		const targetHeight = 18;
		for (let i = lines.length; i < targetHeight; i++) {
			lines.push(this.row(""));
		}

		lines.push(this.renderFooter(" [Enter] Confirm • [Space] Toggle • [Esc] Cancel "));
		return lines;
	}

	/** Get footer text based on mode */
	private getFooterText(): string {
		const bgLabel = this.runInBackground ? "[b]g:ON" : "[b]g";
		switch (this.mode) {
			case "single": {
				return ` [Enter] Run • [Esc] Cancel • e m t w s ${bgLabel} S `;
			}
			case "parallel": {
				return ` [Enter] Run • [Esc] Cancel • e m t s ${bgLabel} S • ↑↓ Nav `;
			}
			case "chain": {
				return ` [Enter] Run • [Esc] Cancel • e m t w r p s ${bgLabel} S W • ↑↓ Nav `;
			}
		}
	}

	private appendSaveMessage(lines: string[]): void {
		if (!this.saveMessage) {
			return;
		}
		const color = this.saveMessage.type === "error" ? "error" : "success";
		lines.push(this.row(` ${this.theme.fg(color, this.saveMessage.text)}`));
	}

	/** Render single agent mode (simplified view) */
	private renderSingleMode(): string[] {
		const innerW = this.width - 2;
		const th = this.theme;
		const lines: string[] = [];

		// Header with agent name
		const agentName = this.agentConfigs[0]?.name ?? "unknown";
		const maxHeaderLen = innerW - 4;
		const headerText = ` Agent: ${truncateToWidth(agentName, maxHeaderLen - 9)} `;
		lines.push(this.renderHeader(headerText));
		lines.push(this.row(""));

		// Single step - always index 0, always selected
		const config = this.agentConfigs[0]!;
		const behavior = this.getEffectiveBehavior(0);

		// Agent name with selection indicator
		const stepLabel = config.name;
		lines.push(this.row(` ${th.fg("accent", `▶ ${stepLabel}`)}`));

		// Task line
		const template = (this.templates[0] ?? "").split("\n")[0] ?? "";
		const taskLabel = th.fg("dim", "task: ");
		lines.push(this.row(`     ${taskLabel}${truncateToWidth(template, innerW - 12)}`));

		// Model line
		const effectiveModel = this.getEffectiveModel(0);
		const override = this.behaviorOverrides.get(0);
		const isOverridden = override?.model !== undefined;
		const modelValue = isOverridden ? th.fg("warning", effectiveModel) + th.fg("dim", " ✎") : effectiveModel;
		const modelLabel = th.fg("dim", "model: ");
		lines.push(this.row(`     ${modelLabel}${truncateToWidth(modelValue, innerW - 13)}`));

		// Writes line (output file)
		const writesValue =
			behavior.output === false ? th.fg("dim", "(disabled)") : behavior.output || th.fg("dim", "(none)");
		const writesLabel = th.fg("dim", "writes: ");
		lines.push(this.row(`     ${writesLabel}${truncateToWidth(writesValue, innerW - 14)}`));

		const skillsValue =
			behavior.skills === false
				? th.fg("dim", "(disabled)")
				: behavior.skills?.length
					? behavior.skills.join(", ")
					: th.fg("dim", "(none)");
		const skillsLabel = th.fg("dim", "skills: ");
		lines.push(this.row(`     ${skillsLabel}${truncateToWidth(skillsValue, innerW - 14)}`));

		lines.push(this.row(""));

		// Footer
		this.appendSaveMessage(lines);
		lines.push(this.renderFooter(this.getFooterText()));

		return lines;
	}

	/** Render parallel mode (multi-task view without chain features) */
	private renderParallelMode(): string[] {
		const innerW = this.width - 2;
		const th = this.theme;
		const lines: string[] = [];

		// Header with task count
		const headerText = ` Parallel Tasks (${this.agentConfigs.length}) `;
		lines.push(this.renderHeader(headerText));
		lines.push(this.row(""));

		// Each task
		for (let i = 0; i < this.agentConfigs.length; i++) {
			const config = this.agentConfigs[i]!;
			const isSelected = i === this.selectedStep;

			// Task header (truncate agent name to prevent overflow)
			const color = isSelected ? "accent" : "dim";
			const prefix = isSelected ? "▶ " : "  ";
			const taskPrefix = `Task ${i + 1}: `;
			const maxNameLen = innerW - 4 - prefix.length - taskPrefix.length;
			const agentName = config.name.length > maxNameLen ? `${config.name.slice(0, maxNameLen - 1)}…` : config.name;
			const taskLabel = `${taskPrefix}${agentName}`;
			lines.push(this.row(` ${th.fg(color, prefix + taskLabel)}`));

			// Task line
			const template = (this.templates[i] ?? "").split("\n")[0] ?? "";
			const taskTextLabel = th.fg("dim", "task: ");
			lines.push(this.row(`     ${taskTextLabel}${truncateToWidth(template, innerW - 12)}`));

			// Model line
			const effectiveModel = this.getEffectiveModel(i);
			const override = this.behaviorOverrides.get(i);
			const isOverridden = override?.model !== undefined;
			const modelValue = isOverridden ? th.fg("warning", effectiveModel) + th.fg("dim", " ✎") : effectiveModel;
			const modelLabel = th.fg("dim", "model: ");
			lines.push(this.row(`     ${modelLabel}${truncateToWidth(modelValue, innerW - 13)}`));

			const behavior = this.getEffectiveBehavior(i);
			const skillsValue =
				behavior.skills === false
					? th.fg("dim", "(disabled)")
					: behavior.skills?.length
						? behavior.skills.join(", ")
						: th.fg("dim", "(none)");
			const skillsLabel = th.fg("dim", "skills: ");
			lines.push(this.row(`     ${skillsLabel}${truncateToWidth(skillsValue, innerW - 14)}`));

			lines.push(this.row(""));
		}

		// Footer
		this.appendSaveMessage(lines);
		lines.push(this.renderFooter(this.getFooterText()));

		return lines;
	}

	/** Render chain mode (step selection, preview) */
	private renderChainMode(): string[] {
		const innerW = this.width - 2;
		const th = this.theme;
		const lines: string[] = [];

		// Header with chain name (truncate if too long)
		const chainLabel = this.agentConfigs.map((c) => c.name).join(" → ");
		const maxHeaderLen = innerW - 4;
		const headerText = ` Chain: ${truncateToWidth(chainLabel, maxHeaderLen - 9)} `;
		lines.push(this.renderHeader(headerText));

		lines.push(this.row(""));

		// Original task (truncated) and chain dir
		const taskPreview = truncateToWidth(this.originalTask, innerW - 16);
		lines.push(this.row(` Original Task: ${taskPreview}`));
		// ChainDir is guaranteed to be defined in chain mode
		const chainDirPreview = truncateToWidth(this.chainDir ?? "", innerW - 12);
		lines.push(this.row(` Chain Dir: ${th.fg("dim", chainDirPreview)}`));

		// Chain-wide progress setting
		const progressEnabled = this.agentConfigs.some((_, i) => this.getEffectiveBehavior(i).progress);
		const progressValue = progressEnabled ? th.fg("success", "+ enabled") : th.fg("dim", "- disabled");
		lines.push(this.row(` Progress: ${progressValue} ${th.fg("dim", "(press [p] to toggle)")}`));
		lines.push(this.row(""));

		// Each step
		for (let i = 0; i < this.agentConfigs.length; i++) {
			const config = this.agentConfigs[i]!;
			const isSelected = i === this.selectedStep;
			const behavior = this.getEffectiveBehavior(i);

			// Step header (truncate agent name to prevent overflow)
			const color = isSelected ? "accent" : "dim";
			const prefix = isSelected ? "▶ " : "  ";
			const stepPrefix = `Step ${i + 1}: `;
			const maxNameLen = innerW - 4 - prefix.length - stepPrefix.length; // 4 for " " prefix and padding
			const agentName = config.name.length > maxNameLen ? `${config.name.slice(0, maxNameLen - 1)}…` : config.name;
			const stepLabel = `${stepPrefix}${agentName}`;
			lines.push(this.row(` ${th.fg(color, prefix + stepLabel)}`));

			// Template line (with syntax highlighting for variables)
			const template = (this.templates[i] ?? "").split("\n")[0] ?? "";
			const highlighted = template
				.replaceAll(/\{task\}/g, th.fg("success", "{task}"))
				.replaceAll(/\{previous\}/g, th.fg("warning", "{previous}"))
				.replaceAll(/\{chain_dir\}/g, th.fg("accent", "{chain_dir}"));

			const templateLabel = th.fg("dim", "task: ");
			lines.push(this.row(`     ${templateLabel}${truncateToWidth(highlighted, innerW - 12)}`));

			// Model line (show override indicator if modified)
			const effectiveModel = this.getEffectiveModel(i);
			const override = this.behaviorOverrides.get(i);
			const isOverridden = override?.model !== undefined;
			const modelValue = isOverridden ? th.fg("warning", effectiveModel) + th.fg("dim", " ✎") : effectiveModel;
			const modelLabel = th.fg("dim", "model: ");
			lines.push(this.row(`     ${modelLabel}${truncateToWidth(modelValue, innerW - 13)}`));

			// Writes line (output file) - renamed from "output" for clarity
			const writesValue =
				behavior.output === false ? th.fg("dim", "(disabled)") : behavior.output || th.fg("dim", "(none)");
			const writesLabel = th.fg("dim", "writes: ");
			lines.push(this.row(`     ${writesLabel}${truncateToWidth(writesValue, innerW - 14)}`));

			// Reads line
			const readsValue =
				behavior.reads === false
					? th.fg("dim", "(disabled)")
					: behavior.reads && behavior.reads.length > 0
						? behavior.reads.join(", ")
						: th.fg("dim", "(none)");
			const readsLabel = th.fg("dim", "reads: ");
			lines.push(this.row(`     ${readsLabel}${truncateToWidth(readsValue, innerW - 13)}`));

			const skillsValue =
				behavior.skills === false
					? th.fg("dim", "(disabled)")
					: behavior.skills?.length
						? behavior.skills.join(", ")
						: th.fg("dim", "(none)");
			const skillsLabel = th.fg("dim", "skills: ");
			lines.push(this.row(`     ${skillsLabel}${truncateToWidth(skillsValue, innerW - 14)}`));

			// Progress line - show when chain-wide progress is enabled
			// First step creates & updates, subsequent steps read & update
			if (progressEnabled) {
				const isFirstStep = i === 0;
				const progressAction = isFirstStep
					? th.fg("success", "●") + th.fg("dim", " creates & updates progress.md")
					: th.fg("accent", "↔") + th.fg("dim", " reads & updates progress.md");
				const progressLabel = th.fg("dim", "progress: ");
				lines.push(this.row(`     ${progressLabel}${progressAction}`));
			}

			// Show {previous} indicator for all steps except the last
			// This shows that this step's text response becomes {previous} for the next step
			if (i < this.agentConfigs.length - 1) {
				const nextStepUsePrevious = (this.templates[i + 1] ?? "").includes("{previous}");
				if (nextStepUsePrevious) {
					const indicator = th.fg("dim", "     ↳ response → ") + th.fg("warning", "{previous}");
					lines.push(this.row(indicator));
				}
			}

			lines.push(this.row(""));
		}

		// Footer with keybindings
		this.appendSaveMessage(lines);
		lines.push(this.renderFooter(this.getFooterText()));

		return lines;
	}

	invalidate(): void {}
	dispose(): void {
		if (this.saveMessageTimer) {
			clearTimeout(this.saveMessageTimer);
		}
		this.saveMessageTimer = null;
	}
}