import type {
	AbsSingularQuery,
	JsonPathQuery,
	RelQuery,
	RelSingularQuery,
} from "../../parser/ast.ts";
import { Stack } from "../../utils/stack.ts";
import { getInitialPath, joinPathWithKey } from "../path.ts";
import type { JsonValue } from "../results.ts";
import type { Callback, Context, StackItem } from "../types.ts";
import { visitSegment } from "./segment.ts";

export default function visitQuery(
	ctx: Context,
	root: JsonValue,
	input: JsonValue,
	node: JsonPathQuery | RelQuery | RelSingularQuery | AbsSingularQuery,
	cb: Callback,
): void {
	const stack = new Stack<StackItem>();
	stack.push({
		root,
		path: getInitialPath(ctx.capturePaths),
		value: input,
		index: 0,
	});
	const context: Context = {
		cache: ctx.cache,
		capturePaths: false,
		functions: ctx.functions,
		regexp: ctx.regexp,
		stack,
	};

	while (stack.size > 0) {
		// biome-ignore lint/style/noNonNullAssertion: size is guaranteed to be > 0
		const item = stack.pop()!;
		if (item.index === node.segments.length) {
			cb(item.value, item.path);
			continue;
		}

		const { path, value, index } = item;
		const segment = node.segments[index];
		visitSegment(context, item, segment.node);

		if (segment.type === "DescendantSegment") {
			if (Array.isArray(value)) {
				for (let i = 0; i < value.length; i++) {
					stack.push({
						root,
						path: joinPathWithKey(path, i),
						value: value[i],
						index,
					});
				}
			} else if (value !== null && typeof value === "object") {
				for (const key of Object.keys(value) as (keyof typeof value)[]) {
					stack.push({
						root,
						path: joinPathWithKey(path, key),
						value: value[key],
						index,
					});
				}
			}
		}
	}
}