/* eslint-disable no-console */
import { hasImportDeclaration, isDecendantOfType } from '@hypermod/utils';
import type { API, Collection, FileInfo, JSCodeshift, TemplateElement } from 'jscodeshift';

import CSSTransformer from '../css-to-design-tokens/transform';
import { activeTokens } from '../utils/active-tokens';

import { cleanMeta } from './utils/clean-meta';
import { includesHardCodedColor, isHardCodedColor } from './utils/color';
import { containsReplaceableCSSDeclarations } from './utils/contains-replaceable-css-declarations';
import { findEndIndexOfCSSExpression } from './utils/find-end-index-of-css-expression';
import { findFirstNonspaceIndexAfter } from './utils/find-first-nonspace-index-after';
import Search from './utils/fuzzy-search';
import { getMetaFromAncestors } from './utils/get-meta-from-ancestors';
import { isBoldColor } from './utils/is-bold-color';
import { isDecendantOfToken } from './utils/is-decendant-of-token';
import { isLegacyColor } from './utils/is-legacy-color';
import { isLegacyNamedColor } from './utils/is-legacy-named-color';
import { isParentOfToken } from './utils/is-parent-of-token';
import { kebabize } from './utils/kebabize';
import { legacyColorMetaMap } from './utils/legacy-color-meta-map';
import { splitAtIndex } from './utils/split-at-index';

function insertTokenImport(j: JSCodeshift, source: Collection<any>) {
	if (hasImportDeclaration(j, source, '@atlaskit/tokens')) {
		return;
	}

	const newImport = j.importDeclaration(
		[j.importSpecifier(j.identifier('token'))],
		j.stringLiteral('@atlaskit/tokens'),
	);

	source.get().node.program.body.unshift(newImport);
}

function buildToken(j: JSCodeshift, tokenId: string, node: any) {
	const callExpr = j.callExpression(
		j.identifier('token'),
		[j.stringLiteral(tokenId), node].filter(Boolean),
	);

	return callExpr;
}

// Wrap over the j.templateElement builder to provide a more convenient API.
function buildTemplateElement(
	j: JSCodeshift,
	text: string,
	options: { tail?: boolean; fromNode?: TemplateElement | null } = {
		tail: false,
		fromNode: null,
	},
) {
	let tail;
	if (options.fromNode) {
		tail = options.fromNode.tail;
	} else {
		tail = !!options.tail;
	}

	return j.templateElement({ raw: text, cooked: null }, tail);
}

function getColorFromIdentifier(expression: any) {
	let value = '';

	if (expression.type === 'Identifier') {
		value = expression.name;
	}

	if (expression.type === 'StringLiteral') {
		value = expression.value;
	}

	if (
		expression.type === 'MemberExpression' &&
		expression.object.name === 'colors' &&
		isLegacyColor(expression.property.name)
	) {
		value = expression.property.name;
	}

	return value;
}

function getTokenFromNode(j: JSCodeshift, path: any, value: string, propertyName: string): string {
	const valueMeta = cleanMeta(legacyColorMetaMap[value!] || []);
	const ancestorMeta = cleanMeta(
		// @ts-ignore - TS2872 TypeScript 5.9.2 upgrade
		[...getMetaFromAncestors(j, path), ...kebabize(propertyName).split('-')] || [],
	);

	let property = cleanMeta([kebabize(propertyName)])[0];

	// Attempt to find a property from ancestors if one is not found
	if (!property || !['border', 'icon', 'background', 'text'].includes(property)) {
		if (ancestorMeta.includes('border')) {
			property = 'border';
		}

		if (ancestorMeta.includes('icon')) {
			property = 'icon';
		}

		if (ancestorMeta.includes('background')) {
			property = 'background';
		}

		if (ancestorMeta.includes('color')) {
			property = 'text';
		}
	}

	let meta: string[] = [];
	let possibleTokens = activeTokens;

	if (property === 'text') {
		possibleTokens = activeTokens.filter((token) => token.includes('.text'));

		if (valueMeta.includes('neutral')) {
			meta.push('color', 'text');
		}

		if (valueMeta.includes('neutral') && (value === 'N400' || value === 'N500')) {
			meta.push('color', 'text', 'subtle');
		}

		if (
			valueMeta.includes('neutral') &&
			(value === 'N80' ||
				value === 'N100' ||
				value === 'N200' ||
				value === 'N300' ||
				value === 'N400')
		) {
			meta.push('color', 'text', 'subtlest');
		}

		// handle non-neutrals
		if (!valueMeta.includes('neutral')) {
			meta.push('color', ...ancestorMeta, ...valueMeta);
		}
	}

	if (property === 'background' || property === 'background-color') {
		if (ancestorMeta.includes('disabled')) {
			// disabled backgrounds
			meta.push(property, ...ancestorMeta);
		} else if (
			// Surfaces
			valueMeta.includes('neutral') &&
			value !== 'N100' &&
			value !== 'N200' &&
			value !== 'N300' &&
			value !== 'N400' &&
			value !== 'N500' &&
			value !== 'N600' &&
			value !== 'N700' &&
			value !== 'N800'
		) {
			meta.push('surface', ...ancestorMeta);
		} else if (value.includes('N0')) {
			// default surface
			meta.push('elevation', 'surface');
		} else if (valueMeta.includes('neutral') && isBoldColor(value)) {
			// bold netural backgrounds
			meta.push('background', 'neutral', 'bold');
		} else if (valueMeta.includes('neutral')) {
			// netural backgrounds
			meta.push('background', 'neutral');
		}
	}

	if (
		property === 'border' ||
		property === 'border-color' ||
		property === 'border-left' ||
		property === 'border-right' ||
		property === 'border-top' ||
		property === 'border-bottom' ||
		property === 'outline' ||
		property === 'outline-color'
	) {
		possibleTokens = activeTokens.filter(
			(token) => token.includes('.border') || token.includes('.focus'),
		);

		if (valueMeta.includes('neutral')) {
			// standard netural boarder
			meta.push('color', 'border', ...ancestorMeta);
		} else {
			meta.push('border', ...valueMeta, ...ancestorMeta);
		}
	}

	if (ancestorMeta.includes('icon')) {
		possibleTokens = activeTokens.filter((token) => token.includes('.icon'));

		if (ancestorMeta.includes('disabled')) {
			// disabled backgrounds
			meta.push('disabled');
		}

		meta.push('color', 'icon', ...valueMeta);
	}

	// Fallback if guided behavior yields nothing
	if (meta.length === 0) {
		meta.push(property, ...valueMeta, ...ancestorMeta);
	}

	const search = Search(possibleTokens, false);
	const results: [number, string][] = search.get(meta.join(' '));

	let tokenId = ['MISSING_TOKEN'];

	if (results) {
		tokenId = results.map((result) => result[1]) as any;
	}

	return tokenId[0];
}

function parseCSSPropertyName(cssString: string) {
	const lastColonIndex = cssString.lastIndexOf(':');
	if (lastColonIndex === -1) {
		return { colonIndex: null, cssPropertyName: null };
	}

	const propertyNameEndIndex = Math.max(
		cssString.lastIndexOf(';', lastColonIndex),
		cssString.lastIndexOf(' ', lastColonIndex),
		-1,
	);

	const startIndex = propertyNameEndIndex + 1;
	return {
		cssPropertyName: cssString.slice(startIndex, lastColonIndex).trim(),
		colonIndex: lastColonIndex,
	};
}

export default async function transformer(
	file: FileInfo,
	api: API,
	_debug = false,
): Promise<string> {
	const j = api.jscodeshift;
	const source = j(file.source);
	let transformed = false;

	// Objects
	source.find(j.ObjectProperty).forEach((path) => {
		if (path.value.value.type === 'ObjectExpression') {
			return;
		}

		// Avoid transforming objects that are default arguments
		if (
			path.parent.parent.value.type === 'ArrowFunctionExpression' ||
			path.parent.parent.value.type === 'FunctionDeclaration'
		) {
			return;
		}

		if (isParentOfToken(j, path.value.value)) {
			return;
		}

		const value = getColorFromIdentifier(path.value.value);

		if (
			!value ||
			(!includesHardCodedColor(value) &&
				!isHardCodedColor(value) &&
				!isLegacyColor(value) &&
				!isLegacyNamedColor(value))
		) {
			return;
		}

		let key;

		if (path.value.key.type === 'NumericLiteral' || path.value.key.type === 'StringLiteral') {
			key = path.value.key.value.toString();
		}

		if (path.value.key.type === 'Identifier') {
			key = path.value.key.name;
		}

		// Key is a node type we do not support
		if (!key) {
			return;
		}

		const tokenId = getTokenFromNode(j, path, value, key);

		insertTokenImport(j, source);

		j(path).replaceWith(j.objectProperty(path.value.key, buildToken(j, tokenId, path.value.value)));

		transformed = true;
	});

	// JSX props
	source.find(j.JSXAttribute).forEach((path) => {
		if (path.value?.value?.type !== 'JSXExpressionContainer') {
			return;
		}

		if (isParentOfToken(j, path)) {
			return;
		}

		const expression = path.value.value.expression;
		const value = getColorFromIdentifier(expression);

		if (
			!value ||
			(!includesHardCodedColor(value) &&
				!isHardCodedColor(value) &&
				!isLegacyColor(value) &&
				!isLegacyNamedColor(value))
		) {
			return;
		}

		const tokenId = getTokenFromNode(j, path, value, path.value.name.name as string);
		insertTokenImport(j, source);

		j(path)
			.find(j.JSXExpressionContainer)
			.forEach((path) => {
				const tokenNode = buildToken(j, tokenId, path.value.expression);
				j(path).replaceWith(j.jsxExpressionContainer(tokenNode));
			});

		transformed = true;
	});

	// Strings
	source.find(j.StringLiteral).forEach((path) => {
		j(path)
			.filter((expression) => !isDecendantOfType(j, expression, j.ObjectExpression))
			.forEach((path) => {
				const value = path.value.value;

				if (replaceStringLiteralIfItConsistsOnlyOfColor(j, path, value)) {
					transformed = true;
				}
			});
	});

	const templateLiteralPaths = source.find(j.TemplateLiteral).paths();

	for (const path of templateLiteralPaths) {
		// Background: a 'type: TemplateLiteral' Node has quasis and expressions
		// (see ast-types/src/gen/namedTypes.ts), and invariant holds that
		// quasis.length === expression.length + 1.
		//
		// eg `${foo}bar` has quasis [Node(''), Node('bar')] and expressions
		// [Node('foo')]. Each quasi has type: 'TemplateElement'; expressions are
		// probably safe to treat as subtypes of Expression, though ast-types
		// codebase has a more involved definition.
		if (path.value.expressions.length === 0) {
			// A single-quasi (equivalently, no-expression) template literal is
			// basically just a string literal, possibly multi-line. We handle the
			// simple `#ababab` case here, and the multi-line case after.
			const text = path.value.quasis[0].value.raw;

			if (replaceStringLiteralIfItConsistsOnlyOfColor(j, path, text)) {
				transformed = true;
			}
		} else {
			j(path)
				.find(j.Expression)
				.filter((expressionPath) => {
					// jscodeshift walks over the whole tree; we are interested only in
					// the direct children: i.e. top-level expressions appearing in ${}.
					return expressionPath.parent === path;
				})
				.forEach((expressionPath, expressionIndex) => {
					if (replaceTemplateLiteralExpression(j, path, expressionPath, expressionIndex)) {
						transformed = true;
					}
				});
		}

		// No matter if we have one big quasi or many small chunks between
		// expressions (which potentially have been transformed), try to pass them
		// through the CSS transformer; it's robust enough to understand malformed
		// CSS that would result if we split e.g. this template:
		//
		// `${gridSize}px; color: red;`, giving `px; color: red;` as input; or
		// `@media ${mobile} { color: red }`, giving `{ color: red }`.
		const quasiPaths = j(path)
			.find(j.TemplateElement)
			.filter((quasiPath) => {
				return quasiPath.parent === path;
			})
			.paths();

		for (const quasiPath of quasiPaths) {
			const text = quasiPath.value.value.raw;
			if (includesHardCodedColor(text) && containsReplaceableCSSDeclarations(text)) {
				const newCSS = await CSSTransformer(text);

				j(quasiPath).replaceWith(buildTemplateElement(j, newCSS));
				transformed = true;
			}
		}
	}

	function replaceStringLiteralIfItConsistsOnlyOfColor(j: any, path: any, value: string) {
		if (isDecendantOfToken(j, path)) {
			return false;
		}

		if (isHardCodedColor(value) && !isLegacyColor(value) && !isLegacyNamedColor(value)) {
			const parent = path.parent.value;
			let key = '';

			if (parent.type === 'VariableDeclarator') {
				key = parent.id.name;
			}

			const tokenId = getTokenFromNode(j, path, value, key);

			insertTokenImport(j, source);

			j(path).replaceWith(buildToken(j, tokenId, path.value));

			return true;
		}

		return false;
	}

	function replaceTemplateLiteralExpression(
		j: any,
		mainPath: any,
		expressionPath: any,
		expressionIndex: any,
	) {
		const expression = expressionPath.value;
		if (!(expression.type === 'MemberExpression' || expression.type === 'Identifier')) {
			return false;
		}

		if (isDecendantOfToken(j, expressionPath)) {
			return false;
		}

		const value = getColorFromIdentifier(expression);

		if (
			!value ||
			(!includesHardCodedColor(value) &&
				!isHardCodedColor(value) &&
				!isLegacyColor(value) &&
				!isLegacyNamedColor(value))
		) {
			return false;
		}

		const precedingQuasi = mainPath.value.quasis[expressionIndex];
		const precedingQuasiText = precedingQuasi.value.raw;
		const { cssPropertyName, colonIndex } = parseCSSPropertyName(precedingQuasiText);

		if (!cssPropertyName) {
			return false;
		}

		const tokenId = getTokenFromNode(j, expressionPath, value, cssPropertyName);

		insertTokenImport(j, source);

		const newQuasis = [...mainPath.value.quasis];
		const newExpressions = [...mainPath.value.expressions];

		if (cssPropertyName !== 'box-shadow') {
			const tokenExpression = buildToken(j, tokenId, expressionPath.value);

			newExpressions[expressionIndex] = tokenExpression;
		} else {
			// box-shadow is a multi-part property where the color can appear at any
			// part position (even though the standard suggests that color comes
			// last, browsers' CSS parsers are more lax). If we get here, then the
			// color part is replaceable.  Textually, it's something like:
			//
			// <rules before>; box-shadow: 0 1px ${colors.N50} 2rem; <rules after>
			//
			// the fallback value will be multipart, i.e. the token call is
			//
			// token(<replacedValue>, `0 1px ${colors.N50} 2rem`)
			//
			// and it's wrapped in a substitution like this:
			//
			// <rules before>; box-shadow: ${token(<...>)}; <rules after>
			//
			// We stich the fallback from the last part of preceding quasi (after
			// colon) and the first part of the following quasi (before ';' or '}').
			//
			// If multiple box-shadows are comma-separated but only one of them has a
			// replaceable color and others are hard-coded, this logic would still
			// work. When multiple shadows have expressions, it's unfortunately not
			// possible to proceed because we cannot find where the value ends from a
			// single following quasi.
			const valueStartIndex = findFirstNonspaceIndexAfter(precedingQuasiText, colonIndex);

			const [newPrecedingQuasiText, partialValueBeginning] = splitAtIndex(
				precedingQuasiText,
				valueStartIndex,
			);

			const followingQuasi = mainPath.value.quasis[expressionIndex + 1];
			const followingQuasiText = followingQuasi.value.raw;

			const valueEndIndex = findEndIndexOfCSSExpression(followingQuasiText, followingQuasi.tail);
			if (!valueEndIndex) {
				console.warn('cannot find end of box-shadow value, please check manually');
				return false;
			}
			const [partialValueEnd, newFollowingQuasiText] = splitAtIndex(
				followingQuasiText,
				valueEndIndex + 1,
			);

			const internalQuasis = [
				buildTemplateElement(j, partialValueBeginning, { tail: false }),
				buildTemplateElement(j, partialValueEnd, { tail: true }),
			];
			const internalExpressions = [expressionPath.value];
			const newFallback = j.templateLiteral(internalQuasis, internalExpressions);
			const newExpression = buildToken(j, tokenId, newFallback);

			newQuasis[expressionIndex] = buildTemplateElement(j, newPrecedingQuasiText, {
				fromNode: newQuasis[expressionIndex],
			});
			newExpressions[expressionIndex] = newExpression;
			newQuasis[expressionIndex + 1] = buildTemplateElement(j, newFollowingQuasiText, {
				fromNode: newQuasis[expressionIndex],
			});
		}
		mainPath.replace(j.templateLiteral(newQuasis, newExpressions));
		return true;
	}

	return transformed ? source.toSource() : file.source;
}