import { SourceUnit } from 'solidity-ast';
import { findAll } from 'solidity-ast/utils';
import { getNodeBounds } from '../solc/ast-utils';
import { hasConstructorOverride, hasOverride } from '../utils/upgrades-overrides';

import { Transformation } from './type';

export function* removeStateVarInits(sourceUnit: SourceUnit): Generator<Transformation> {
  for (const contractNode of findAll('ContractDefinition', sourceUnit)) {
    if (hasConstructorOverride(contractNode)) {
      continue;
    }

    for (const varDecl of findAll('VariableDeclaration', contractNode)) {
      if (varDecl.stateVariable && varDecl.value && !varDecl.constant) {
        if (hasOverride(varDecl, 'state-variable-assignment')) {
          continue;
        }

        yield {
          ...getNodeBounds(varDecl),
          kind: 'purge-var-inits',
          transform: source => source.replace(/\s*=.*/s, ''),
        };
      }
    }
  }
}