/**
 * Copyright (c) 2026, Salesforce, Inc.,
 * All rights reserved.
 * For full license text, see the LICENSE.txt file
 */

import { COMMANDS, type CommandDef } from "./command-registry.js";
import type { QuerySession } from "./session.js";
import type { WalkerResult } from "./walker.js";

// ── Interactive mode flag ─────────────────────────────────────────────────────

let _interactiveMode = false;

export function setInteractiveMode(on: boolean): void {
	_interactiveMode = on;
}

export function isInteractiveMode(): boolean {
	return _interactiveMode;
}

// ── Backward-compatible re-export ─────────────────────────────────────────────
// QUERY_COMMANDS was the original registry. It now delegates to the canonical
// COMMANDS array in command-registry.ts so there is a single source of truth.
export { COMMANDS as QUERY_COMMANDS };

// ── Formatting helpers ───────────────────────────────────────────────────────

export function formatHelp(topic?: string): string {
	const lines: string[] = [];

	if (topic) {
		const spec: CommandDef | undefined = COMMANDS.find((c) => c.name === topic);
		if (!spec) {
			return `Unknown help topic: "${topic}". Run \`help\` with no arguments for a full list.`;
		}
		lines.push(`${spec.name} — ${spec.summary}`);
		lines.push("");
		const usagePrefix = _interactiveMode ? "" : "graphiti ";
		const usageStr = spec.usage.startsWith("graphiti ")
			? spec.usage
			: `${usagePrefix}${spec.usage}`;
		lines.push(`Usage: ${usageStr}`);
		if (spec.subcommands && spec.subcommands.length > 0) {
			lines.push("");
			lines.push("Subcommands:");
			for (const sub of spec.subcommands) {
				lines.push(`  ${sub.usage.padEnd(32)} ${sub.description}`);
			}
		}

		if (topic === "ls") {
			lines.push("");
			lines.push("Search behavior (--search):");
			lines.push('  Multiple terms are OR-matched: --search "Name Id" matches fields');
			lines.push('  containing either "Name" or "Id". Each term is prefix-matched');
			lines.push('  against CamelCase word segments, so "Id" matches "AccountId"');
			lines.push('  but not "Hide".');
		}

		if (topic === "alias" || topic === "mkdir") {
			lines.push("");
			lines.push("Multi-query composition:");
			lines.push("  Use alias to create multiple named instances of the same field,");
			lines.push("  each with different arguments. This lets you combine several queries");
			lines.push("  into a single GraphQL request (e.g. dashboard tiles + lists).");
			lines.push("");
			lines.push("  # Full end-to-end example (from /query/uiapi/query):");
			lines.push("  alias newCases Case");
			lines.push('  set newCases/@args/where \'{"Status":{"eq":"New"}}\'');
			lines.push("  set newCases/@args/first 10");
			lines.push("  select newCases/edges/node/Id newCases/edges/node/Subject/value");
			lines.push("");
			lines.push("  alias myCases Case");
			lines.push("  set myCases/@args/scope MINE");
			lines.push("  set myCases/@args/first 20");
			lines.push("  select myCases/edges/node/Id myCases/edges/node/Status/value");
			lines.push("");
			lines.push("  show   # see the combined query");
		}

		if (topic === "chain") {
			lines.push("");
			lines.push("Note: session management commands (new, use, connect, describe,");
			lines.push("interactive) must be run as separate commands before chaining.");
			lines.push("Only session-scoped commands (cd, ls, select, set, var, etc.)");
			lines.push("can be used inside a chain.");
		}

		if (topic === "set" || topic === "assign") {
			lines.push("");
			lines.push("Inline key=value syntax (preferred):");
			lines.push("  set first=10                              # set on current field");
			lines.push("  set uiapi/query/Case first=10 scope=MINE  # with absolute field path");
			lines.push('  set where=\'{"Status":{"eq":"New"}}\'       # JSON value');
			lines.push("");
			lines.push("Legacy pair syntax:");
			lines.push("  set @args/first 10");
			lines.push('  set @args/where/Name/like "Acme%"');
		}

		lines.push("");
		lines.push("Examples:");
		for (const ex of spec.examples) {
			const exPrefix = _interactiveMode ? "  " : "  ";
			lines.push(`${exPrefix}${ex}`);
		}
		return lines.join("\n");
	}

	lines.push("Graphiti CLI — Progressive GraphQL query builder for Salesforce");
	lines.push("");
	lines.push(
		"Session resolution: --session / -s flag > GRAPHITI_SESSION env var > ~/.graphiti/active",
	);
	lines.push("JSON output: --json flag or GRAPHITI_AGENT=1 env var");
	lines.push("");
	lines.push("Setup:");
	for (const name of ["new", "use", "connect"]) {
		const spec = COMMANDS.find((c) => c.name === name);
		if (spec) lines.push(`  ${spec.name.padEnd(12)} ${spec.summary}`);
	}
	lines.push("");
	lines.push("Navigation:");
	for (const name of ["pwd", "ls", "cd"]) {
		const spec = COMMANDS.find((c) => c.name === name)!;
		lines.push(`  ${spec.name.padEnd(12)} ${spec.summary}`);
	}
	lines.push("");
	lines.push("Query Building:");
	for (const name of ["select", "drop", "alias", "optional", "undo"]) {
		const spec = COMMANDS.find((c) => c.name === name)!;
		lines.push(`  ${spec.name.padEnd(12)} ${spec.summary}`);
	}
	lines.push("");
	lines.push("Arguments & Variables:");
	for (const name of ["set", "unset", "var"]) {
		const spec = COMMANDS.find((c) => c.name === name)!;
		lines.push(`  ${spec.name.padEnd(12)} ${spec.summary}`);
	}
	lines.push("");
	lines.push("Review & Execute:");
	for (const name of ["show", "check", "run", "describe", "codegen"]) {
		const spec = COMMANDS.find((c) => c.name === name)!;
		lines.push(`  ${spec.name.padEnd(12)} ${spec.summary}`);
	}
	lines.push("");
	lines.push("Session Management:");
	for (const name of ["sessions", "clone", "reset"]) {
		const spec = COMMANDS.find((c) => c.name === name)!;
		lines.push(`  ${spec.name.padEnd(12)} ${spec.summary}`);
	}
	lines.push("");
	lines.push("Other:");
	const otherCommands = _interactiveMode ? ["chain", "help"] : ["chain", "help", "interactive"];
	for (const name of otherCommands) {
		const spec = COMMANDS.find((c) => c.name === name);
		if (spec) lines.push(`  ${spec.name.padEnd(12)} ${spec.summary}`);
	}
	lines.push("");
	lines.push("Run `help <subcommand>` for detailed usage and examples.");
	return lines.join("\n");
}

// ── Next-steps hints ─────────────────────────────────────────────────────────

export interface NextStepsContext {
	sessionId: string;
	command: string;
	walkerResult?: WalkerResult;
	session?: QuerySession;
}

export function formatNextSteps(ctx: NextStepsContext): string {
	const { sessionId: sid, command, walkerResult: wr, session } = ctx;
	const lines: string[] = [];
	const p = (cmd: string, desc: string) => {
		if (_interactiveMode) {
			lines.push(`  ${cmd.padEnd(36)} # ${desc}`);
		} else {
			lines.push(`  graphiti query ${sid} ${cmd.padEnd(36)} # ${desc}`);
		}
	};

	const isRoot = !session || session.navigationPath.length === 0;
	const hasSelections = session ? session.nodes.length > 0 : false;
	const hasArgs = wr && wr.args.length > 0;
	const isLeaf = wr?.isLeaf ?? false;
	const _hasFragments = wr && wr.possibleTypes.length > 0;
	const hasFields = wr && !wr.isLeaf && wr.fields.length > 0;

	lines.push("");
	lines.push("Next steps:");

	switch (command) {
		case "new": {
			p("cd query", "navigate into the query tree");
			p("ls", "see available root fields");
			p("interactive", "start an interactive session");
			break;
		}

		case "ls": {
			if (isLeaf) {
				if (!isRoot && session) {
					const leaf = session.navigationPath[session.navigationPath.length - 1];
					p(`cd ..`, "go up to parent directory");
					p(`select ${leaf}`, "select this leaf field");
				}
			} else {
				if (hasFields) {
					const firstDir = wr!.fields.find((f) => f.typeKind !== "SCALAR" && f.typeKind !== "ENUM");
					const firstLeaf = wr!.fields.find(
						(f) => f.typeKind === "SCALAR" || f.typeKind === "ENUM",
					);
					if (firstDir) p(`cd ${firstDir.name}`, `navigate into ${firstDir.name}/`);
					if (firstLeaf) p(`select ${firstLeaf.name}`, `add ${firstLeaf.name} to projection`);
					const hasConnections = wr!.fields.some((f) => f.typeName.includes("Connection"));
					if (hasConnections && firstDir)
						p(`alias myAlias ${firstDir.name}`, "compose multiple queries via aliases");
				}
				if (hasArgs) p(`cd @args`, "navigate into arguments");
				if (!isRoot) p(`cd ..`, "go up one level");
			}
			break;
		}

		case "cd": {
			p(`ls`, "see contents at this path");
			if (hasArgs) p(`cd @args`, "configure field arguments");
			if (hasFields) {
				const firstLeaf = wr!.fields.find((f) => f.typeKind === "SCALAR" || f.typeKind === "ENUM");
				if (firstLeaf) p(`select ${firstLeaf.name}`, `add ${firstLeaf.name} to projection`);
			}
			break;
		}

		case "select": {
			p(`ls`, "see more available fields");
			if (!isRoot) p(`cd ..`, "go up to parent");
			if (hasSelections) {
				p(`show`, "preview the current query string");
				p(`check`, "validate the query");
			}
			break;
		}

		case "assign":
		case "set": {
			p(`show`, "preview query with arguments");
			p(`ls`, "see other fields to set");
			if (hasSelections) p(`check`, "validate the query");
			break;
		}

		case "define":
		case "var": {
			p(`cd /variables/$varName`, "navigate into the variable to set values");
			p(`show`, "preview the query signature");
			break;
		}

		case "show": {
			p(`check`, "validate the query");
			if (hasSelections) p(`run`, "execute the query against the org");
			break;
		}

		case "validate":
		case "check": {
			if (hasSelections) p(`run`, "execute the validated query");
			p(`show`, "preview the query string");
			break;
		}

		default: {
			p(`ls`, "list contents at current path");
			p(`show`, "preview the current query");
			if (hasSelections) p(`check`, "validate the query");
			break;
		}
	}

	if (lines.length <= 2) {
		p(`help`, "show all available commands");
	}

	return lines.join("\n");
}