import ts from "typescript";

import { IdentifierFactory } from "../../factories/IdentifierFactory";
import { StatementFactory } from "../../factories/StatementFactory";
import { TypeFactory } from "../../factories/TypeFactory";

import { Escaper } from "../../utils/Escaper";

import { metadata_to_pattern } from "../internal/metadata_to_pattern";
import { IExpressionEntry } from "./IExpressionEntry";

export namespace CloneJoiner {
  export const object = (
    input: ts.Expression,
    entries: IExpressionEntry<ts.Expression>[],
  ): ts.ConciseBody => {
    if (entries.length === 0) return ts.factory.createIdentifier("{}");

    const regular = entries.filter((e) => e.key.isSoleLiteral());
    const dynamic = entries.filter((e) => !e.key.isSoleLiteral());
    const literal = ts.factory.createObjectLiteralExpression(
      regular.map((entry) => {
        const str: string = entry.key.getSoleLiteral()!;
        return ts.factory.createPropertyAssignment(
          Escaper.variable(str) ? str : ts.factory.createStringLiteral(str),
          entry.expression,
        );
      }),
      true,
    );
    if (dynamic.length === 0) return literal;

    const key = ts.factory.createIdentifier("key");
    const output = ts.factory.createIdentifier("output");

    const statements: ts.Statement[] = [];
    if (regular.length !== 0)
      statements.push(
        ts.factory.createIfStatement(
          ts.factory.createCallExpression(
            IdentifierFactory.access(
              ts.factory.createArrayLiteralExpression(
                regular.map((r) =>
                  ts.factory.createStringLiteral(r.key.getSoleLiteral()!),
                ),
              ),
            )("some"),
            undefined,
            [
              ts.factory.createArrowFunction(
                undefined,
                undefined,
                [IdentifierFactory.parameter("regular")],
                undefined,
                undefined,
                ts.factory.createStrictEquality(
                  ts.factory.createIdentifier("regular"),
                  ts.factory.createIdentifier("key"),
                ),
              ),
            ],
          ),
          ts.factory.createContinueStatement(),
        ),
      );
    statements.push(
      ...dynamic.map((entry) =>
        ts.factory.createIfStatement(
          ts.factory.createCallExpression(
            ts.factory.createIdentifier(
              `RegExp(/${metadata_to_pattern(true)(entry.key)}/).test`,
            ),
            undefined,
            [key],
          ),
          ts.factory.createBlock([
            ts.factory.createExpressionStatement(
              ts.factory.createBinaryExpression(
                ts.factory.createElementAccessExpression(output, key),
                ts.factory.createToken(ts.SyntaxKind.EqualsToken),
                entry.expression,
              ),
            ),
            ts.factory.createContinueStatement(),
          ]),
        ),
      ),
    );

    return ts.factory.createBlock([
      StatementFactory.constant(
        "output",
        ts.factory.createAsExpression(literal, TypeFactory.keyword("any")),
      ),
      ts.factory.createForOfStatement(
        undefined,
        StatementFactory.entry("key")("value"),
        ts.factory.createCallExpression(
          ts.factory.createIdentifier("Object.entries"),
          undefined,
          [input],
        ),
        ts.factory.createBlock(statements),
      ),
      ts.factory.createReturnStatement(output),
    ]);
  };

  export const tuple = (
    children: ts.Expression[],
    rest: ts.Expression | null,
  ): ts.Expression => {
    return ts.factory.createAsExpression(
      ts.factory.createArrayLiteralExpression(
        rest === null
          ? children
          : [...children, ts.factory.createSpreadElement(rest)],
        true,
      ),
      TypeFactory.keyword("any"),
    );
  };

  export const array = (input: ts.Expression, arrow: ts.Expression) =>
    ts.factory.createCallExpression(
      ts.factory.createPropertyAccessExpression(input, "map"),
      undefined,
      [arrow],
    );
}