import CommandClient
import ConfigurationClient
import Dependencies
import DependenciesMacros
import Foundation

public extension DependencyValues {

  /// Represents interactions with the `pandoc` command line application.
  ///
  /// The `pandoc` command line application is used to generate the final output
  /// documents from a home performance assessment project.
  ///
  var pandocClient: PandocClient {
    get { self[PandocClient.self] }
    set { self[PandocClient.self] = newValue }
  }
}

@DependencyClient
public struct PandocClient: Sendable {

  /// Run a pandoc command.
  public var run: Run

  /// Represents the pandoc commands that we can run.
  @DependencyClient
  public struct Run: Sendable {

    /// Generate a latex file from the given options, returning the path the
    /// generated file was written to.
    public var generateLatex: @Sendable (RunOptions) async throws -> String

    /// Generate an html file from the given options, returning the path the
    /// generated file was written to.
    public var generateHtml: @Sendable (RunOptions) async throws -> String

    /// Generate a pdf file from the given options, returning the path the
    /// generated file was written to.
    public var generatePdf: @Sendable (RunOptions, String?) async throws -> String

    /// Generate a pdf file from the given options, returning the path the
    /// generated file was written to.
    ///
    /// - Parameters:
    ///   - options: The shared run options.
    ///   - pdfEngine: The pdf-engine to use to generate the pdf file.
    public func generatePdf(
      _ options: RunOptions,
      pdfEngine: String? = nil
    ) async throws -> String {
      try await generatePdf(options, pdfEngine)
    }

  }

  /// Represents the shared options used to run a `pandoc` command.
  ///
  ///
  public struct RunOptions: Equatable, Sendable {

    let buildDirectory: String?
    let extraOptions: [String]?
    let files: [String]?
    let loggingOptions: LoggingOptions
    let includeInHeader: [String]?
    let outputDirectory: String?
    let outputFileName: String?
    let projectDirectory: String?
    let quiet: Bool
    let shell: String?
    let shouldBuildProject: Bool

    /// Create the shared run options.
    ///
    /// - Parameters:
    ///   - buildDirectory: Specify the build directory of the project.
    ///   - extraOptions: Extra arguments / options passed to the `pandoc` command.
    ///   - file: Files used to build the final output.
    ///   - loggingOptions: The logging options used when running the command.
    ///   - includeInHeader: Files to include in the header of the final output document.
    ///   - outputDirectory: Optional output directory for the output file, defaults to current working directory.
    ///   - projectDirectory: Optional project directory, defaults to current working directory.
    ///   - outputFileName: Override the output file name.
    ///   - quiet: Don't log output from the command.
    ///   - shell: Optional shell to use when calling the pandoc command.
    ///   - shouldBuildProject: Build the project prior to generating the output file.
    public init(
      buildDirectory: String? = nil,
      extraOptions: [String]? = nil,
      files: [String]? = nil,
      loggingOptions: LoggingOptions,
      includeInHeader: [String]? = nil,
      outputDirectory: String? = nil,
      projectDirectory: String? = nil,
      outputFileName: String? = nil,
      quiet: Bool = false,
      shell: String? = nil,
      shouldBuild shouldBuildProject: Bool = true
    ) {
      self.buildDirectory = buildDirectory
      self.extraOptions = extraOptions
      self.files = files
      self.loggingOptions = loggingOptions
      self.includeInHeader = includeInHeader
      self.outputDirectory = outputDirectory
      self.outputFileName = outputFileName
      self.projectDirectory = projectDirectory
      self.quiet = quiet
      self.shell = shell
      self.shouldBuildProject = shouldBuildProject
    }

  }

  /// Represents the file types that we can generate output files for.
  @_spi(Internal)
  public enum FileType: Equatable, Sendable {
    case html
    case latex
    case pdf(engine: String?)
  }
}

extension PandocClient: DependencyKey {
  public static let testValue: PandocClient = Self(run: Run())

  public static func live(environment: [String: String]) -> PandocClient {
    .init(
      run: Run(
        generateLatex: { try await $0.run(.latex, environment) },
        generateHtml: { try await $0.run(.html, environment) },
        generatePdf: { try await $0.run(.pdf(engine: $1), environment) }
      )
    )
  }

  public static var liveValue: PandocClient {
    .live(environment: ProcessInfo.processInfo.environment)
  }
}