import Fluent
import Vapor

struct VendorViewController: RouteCollection {
  private let api = VendorApiController()

  func boot(routes: any RoutesBuilder) throws {
    let vendors = routes.protected.grouped("vendors")

    vendors.get(use: index(req:))
    vendors.post(use: create(req:))
    vendors.group(":vendorID") {
      $0.delete(use: delete(req:))
      $0.put(use: update(req:))
    }
  }

  @Sendable
  func index(req: Request) async throws -> View {
    return try await req.view.render("vendors/index", makeCtx(req: req))
  }

  @Sendable
  func create(req: Request) async throws -> View {
    let ctx = try req.content.decode(CreateVendorCTX.self)
    req.logger.debug("CTX: \(ctx)")
    let vendor = Vendor.Create(name: ctx.name).toModel()
    try await vendor.save(on: req.db)

    if let branchString = ctx.branches {
      let branches = branchString.split(separator: ",")
        .map { $0.trimmingCharacters(in: .whitespacesAndNewlines) }

      for branch in branches {
        try await vendor.$branches.create(
          VendorBranch(name: String(branch), vendorId: vendor.requireID()),
          on: req.db
        )
      }
    }

    return try await req.view.render("vendors/table", makeCtx(req: req))
  }

  @Sendable
  func delete(req: Request) async throws -> HTTPStatus {
    try await api.delete(req: req)
  }

  @Sendable
  func update(req: Request) async throws -> View {
    _ = try await api.update(req: req)
    return try await req.view.render("vendors/table", makeCtx(req: req, oob: true))
  }

  private func makeCtx(req: Request, vendor: Vendor? = nil, oob: Bool = false) async throws -> VendorsCTX {
    let vendors = try await Vendor.query(on: req.db)
      .with(\.$branches)
      .sort(\.$name, .ascending)
      .all()
      .map { $0.toDTO() }

    return .init(
      vendors: vendors,
      form: .init(vendor: vendor, oob: oob)
    )
  }
}

struct VendorFormCTX: Content {
  let htmxForm: HtmxFormCTX<Context>

  init(vendor: Vendor? = nil, oob: Bool = false) {
    self.htmxForm = .init(
      formClass: "vendor-form",
      formId: "vendor-form",
      htmxTargetUrl: vendor == nil ? .post("/vendors") : .put("/vendors"),
      htmxTarget: "#vendor-table",
      htmxPushUrl: false,
      htmxResetAfterRequest: true,
      htmxSwapOob: oob ? .outerHTML : nil,
      htmxSwap: oob ? nil : .outerHTML,
      context: .init(vendor: vendor)
    )
  }

  struct Context: Content {
    let vendor: Vendor?
    let branches: String?
    let buttonLabel: String

    init(vendor: Vendor? = nil) {
      self.vendor = vendor
      self.branches = vendor?.branches.map(\.name).joined(separator: ", ")
      self.buttonLabel = vendor == nil ? "Create" : "Update"
    }
  }
}

private struct VendorsCTX: Content {
  let vendors: [Vendor.DTO]
  let form: VendorFormCTX
}

private struct CreateVendorCTX: Content {
  let name: String
  let branches: String?
}