// p4rse, Copyright 2026, Will Hawkins
//
// This file is part of p4rse.
//
// This file is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.

import Common
import SwiftTreeSitter
import TreeSitterExtensions
import TreeSitterP4

let p4lang = Language(tree_sitter_p4())

public func ConfigureP4Parser() -> Result<SwiftTreeSitter.Parser> {
  let p = SwiftTreeSitter.Parser.init()

  do {
    try p.setLanguage(p4lang)
  } catch {
    return Result.Error(Error(withMessage: "Could not configure the P4 parser"))
  }

  return .Ok(p)
}

public func compile(_ s: String) -> Result<CST.Program> {
  let maybe_parser = ConfigureP4Parser()
  guard case .Ok(let p) = maybe_parser else {
    return .Error(maybe_parser.error()!)
  }

  let result = p.parse(s)
  guard let tree = result,
    !tree.isError(lang: p4lang),
    !tree.containsMissing(lang: p4lang)
  else {
    return Result.Error(Error(withMessage: "Could not parse the P4 program"))
  }

  guard let root = tree.rootNode else {
    return Result.Error(Error(withMessage: "No P4 program compiled"))
  }

  let compilation_context = CSTCompilerContext()
  return CST.Program.Parse(node: root, withContext: compilation_context)
}