import DatabaseClientLive
import Dependencies
import Elementary
import SharedModels
import Vapor

private let viewProtectedMiddleware: [any Middleware] = [
  UserPasswordAuthenticator(),
  UserSessionAuthenticator(),
  User.redirectMiddleware { req in
    "/login?next=\(req.url.string)"
  }
]

// TODO: Return `any HTML` instead to make testing the rendered documents easier.
extension SharedModels.ViewRoute {

  var middleware: [any Middleware]? {
    switch self {
    case .index: return viewProtectedMiddleware
    case let .employee(route): return route.middleware
    case .login: return nil
    case let .purchaseOrder(route): return route.middleware
    case let .user(route): return route.middleware
    case let .vendor(route): return route.middleware
    case let .vendorBranch(route): return route.middleware
    }
  }

  func handle(request: Request) async throws -> any AsyncResponseEncodable {
    @Dependency(\.database.users) var users
    switch self {
    case .index:
      return request.redirect(to: Self.router.path(for: .purchaseOrder(.index)))

    case let .employee(route):
      return try await route.handle(request: request)

    case let .login(route):
      switch route {
      case let .index(next: next):
        return await request.render {
          MainPage(displayNav: false, route: .login) {
            UserForm(context: .login(next: next))
          }
        }
      case let .post(login):
        let token = try await users.login(.init(username: login.username, password: login.password))
        let user = try await users.get(token.userID)!
        request.session.authenticate(user)
        request.logger.info("Logged in next: \(login.next ?? "N/A")")
        return await request.render {
          MainPage.loggedIn(next: login.next)
        }
      }

    case let .purchaseOrder(route):
      return try await route.handle(request: request)

    case let .user(route):
      return try await route.handle(request: request)

    case let .vendor(route):
      return try await route.handle(request: request)

    case let .vendorBranch(route):
      return try await route.handle(request: request)
    }
  }
}

extension SharedModels.ViewRoute.EmployeeRoute {

  private func mainPage<C: HTML>(
    _ html: C
  ) async throws -> some SendableHTMLDocument where C: Sendable {
    @Dependency(\.database) var database
    let employees = try await database.employees.fetchAll()
    return MainPage(displayNav: true, route: .employees) {
      div(.class("container")) {
        html
        EmployeeTable(employees: employees)
      }
    }
  }

  var middleware: [any Middleware]? { viewProtectedMiddleware }

  func handle(request: Request) async throws -> any AsyncResponseEncodable {
    @Dependency(\.database.employees) var employees

    switch self {
    case .form:
      return try await request.render(mainPage: mainPage) {
        EmployeeForm(shouldShow: true)
      }

    case let .select(context: context):
      return try await request.render {
        try await context.toHTML(employees: employees.fetchAll())
      }

    case .index:
      return try await request.render { try await mainPage(EmployeeForm()) }

    case let .get(id: id):
      guard let employee = try await employees.get(id) else {
        throw Abort(.badRequest, reason: "Employee id not found.")
      }
      return try await request.render(mainPage: mainPage) {
        EmployeeForm(employee: employee)
      }

    case let .create(employee):
      return try await request.render {
        try await EmployeeTable.Row(employee: employees.create(employee))
      }

    case let .delete(id: id):
      try await employees.delete(id)
      return HTTPStatus.ok

    case let .update(id: id, updates: updates):
      return try await request.render {
        try await EmployeeTable.Row(employee: employees.update(id, updates))
      }
    }
  }

}

extension SharedModels.ViewRoute.PurchaseOrderRoute {
  private func mainPage<C: HTML>(
    _ html: C,
    page: Int,
    limit: Int
  ) async throws -> some SendableHTMLDocument where C: Sendable {
    @Dependency(\.database.purchaseOrders) var purchaseOrders
    let page = try await purchaseOrders.fetchPage(.init(page: page, per: limit))
    return MainPage(displayNav: true, route: .purchaseOrders) {
      div(.class("container"), .id("purchase-order-content")) {
        html
        PurchaseOrderTable(page: page)
      }
    }
  }

  private func mainPage<C: HTML>(
    _ html: C
  ) async throws -> some SendableHTMLDocument where C: Sendable {
    try await mainPage(html, page: 1, limit: 25)
  }

  var middleware: [any Middleware]? { viewProtectedMiddleware }

  func handle(request: Vapor.Request) async throws -> any AsyncResponseEncodable {
    @Dependency(\.database.purchaseOrders) var purchaseOrders
    switch self {
    case .form:
      return try await request.render(mainPage: mainPage) {
        PurchaseOrderForm(shouldShow: true)
      }

    case let .search(route):
      return try await route.handle(request: request)

    case let .create(purchaseOrder):
      return try await request.render {
        try await PurchaseOrderTable.Row(purchaseOrder: purchaseOrders.create(purchaseOrder))
      }

    case let .delete(id: id):
      try await purchaseOrders.delete(id)
      return HTTPStatus.ok

    case .index:
      return try await request.render {
        try await mainPage(PurchaseOrderForm())
      }

    case let .get(id: id):
      guard let purchaseOrder = try await purchaseOrders.get(id) else {
        throw Abort(.badRequest, reason: "Purchase order not found.")
      }
      return try await request.render(mainPage: mainPage) {
        PurchaseOrderForm(purchaseOrder: purchaseOrder, shouldShow: true)
      }

    case let .page(page: page, limit: limit):
      return try await request.render {
        try await PurchaseOrderTable.Rows(
          page: purchaseOrders.fetchPage(.init(page: page, per: limit))
        )
      }
    }
  }

}

extension SharedModels.ViewRoute.PurchaseOrderRoute.Search {

  func mainPage(search: PurchaseOrderSearch = .init()) -> some SendableHTMLDocument {
    MainPage(displayNav: true, route: .purchaseOrders) {
      div(.class("container"), .id("purchase-order-content")) {
        search
        PurchaseOrderTable(
          page: .init(items: [], metadata: .init(page: 0, per: 50, total: 0)),
          context: .search
        )
      }
    }
  }

  func handle(request: Vapor.Request) async throws -> any AsyncResponseEncodable {
    @Dependency(\.database) var database
    switch self {
    case let .index(context: context, table: table):
      let html = PurchaseOrderSearch(context: context)
      if table == true || !request.isHtmxRequest {
        return await request.render { mainPage(search: html) }
      }
      return await request.render { html }

    case let .request(context):
      let results = try await database.purchaseOrders.search(context.toDatabaseQuery(), .init(page: 1, per: 25))
      return await request.render {
        PurchaseOrderTable(page: results, context: .search)
      }
    }
  }
}

extension SharedModels.ViewRoute.UserRoute {

  private func mainPage<C: HTML>(_ html: C) async throws -> some SendableHTMLDocument where C: Sendable {
    @Dependency(\.database) var database
    let users = try await database.users.fetchAll()
    return MainPage(displayNav: true, route: .users) {
      div(.class("container")) {
        html
        UserTable(users: users)
      }
    }
  }

  var middleware: [any Middleware]? {
    viewProtectedMiddleware
  }

  func handle(request: Request) async throws -> any AsyncResponseEncodable {
    @Dependency(\.database.users) var users
    switch self {
    case .form:
      return try await request.render(mainPage: mainPage) {
        UserForm(context: .create)
      }

    case let .create(user):
      return try await request.render {
        try await UserTable.Row(user: users.create(user))
      }

    case let .delete(id: id):
      try await users.delete(id)
      return HTTPStatus.ok

    case .index:
      return try await request.render {
        try await mainPage(UserDetail(user: nil))
      }

    case let .get(id: id):
      guard let user = try await users.get(id) else {
        throw Abort(.badRequest, reason: "User not found.")
      }
      return try await request.render(mainPage: mainPage) {
        UserDetail(user: user)
      }

    case let .update(id: id, updates: updates):
      return try await request.render {
        try await UserTable.Row(user: users.update(id, updates))
      }
    }
  }

}

extension SharedModels.ViewRoute.VendorRoute {
  private func mainPage<C: HTML>(_ html: C) async throws -> some SendableHTMLDocument where C: Sendable {
    @Dependency(\.database) var database
    let vendors = try await database.vendors.fetchAll(.withBranches)
    return MainPage(displayNav: true, route: .vendors) {
      div(.class("container"), .id("content")) {
        html
        VendorTable(vendors: vendors)
      }
    }
  }

  var middleware: [any Middleware]? { viewProtectedMiddleware }

  func handle(request: Request) async throws -> any AsyncResponseEncodable {
    @Dependency(\.database) var database

    switch self {
    case .form:
      return try await request.render(mainPage: mainPage) {
        VendorForm(.float(shouldShow: true))
      }

    case .index:
      return try await request.render {
        try await mainPage(VendorForm())
      }

    case let .create(vendor):
      let vendor = try await database.vendors.create(vendor)
      return await request.render {
        div(.class("container"), .id("content")) {
          VendorDetail(vendor: vendor)
          try await VendorTable(vendors: database.vendors.fetchAll(.withBranches))
        }
      }

    case let .delete(id: id):
      try await database.vendors.delete(id)
      return HTTPStatus.ok

    case let .get(id: id):
      guard let vendor = try await database.vendors.get(id, .withBranches) else {
        throw Abort(.badRequest, reason: "Vendor not found.")
      }
      return try await request.render(mainPage: mainPage) {
        VendorDetail(vendor: vendor)
      }

    case let .update(id: id, updates: updates):
      return try await request.render {
        try await VendorDetail(
          vendor: database.vendors.update(id, with: updates, returnWithBranches: true)
        )
      }
    }
  }
}

extension SharedModels.ViewRoute.VendorBranchRoute {

  var middleware: [any Middleware]? { viewProtectedMiddleware }

  // func html() async throws -> any HTML {
  //   @Dependency(\.database) var database
  //
  //   switch self {
  //   case let .index(for: vendorID):
  //     guard let vendorID else {
  //       throw Abort(.badRequest, reason: "Vendor id not supplied")
  //     }
  //     return try await VendorBranchList(
  //       vendorID: vendorID,
  //       branches: database.vendorBranches.fetchAll(.for(vendorID: vendorID))
  //     )
  //
  //   case let .select(context: context):
  //     return try await context.toHTML(branches: database.vendorBranches.fetchAllWithDetail())
  //
  //   case let .create(branch):
  //     return try await VendorBranchList.Row(branch: database.vendorBranches.create(branch))
  //
  //   case let .delete(id: id):
  //     try await database.vendorBranches.delete(id)
  //     return HTTPStatus.ok
  //   }
  // }

  func handle(request: Request) async throws -> any AsyncResponseEncodable {
    @Dependency(\.database) var database

    switch self {
    case let .index(for: vendorID):
      guard let vendorID else {
        throw Abort(.badRequest, reason: "Vendor id not supplied")
      }
      return try await request.render {
        try await VendorBranchList(
          vendorID: vendorID,
          branches: database.vendorBranches.fetchAll(.for(vendorID: vendorID))
        )
      }

    case let .select(context: context):
      return try await request.render {
        try await context.toHTML(branches: database.vendorBranches.fetchAllWithDetail())
      }

    case let .create(branch):
      return try await request.render {
        try await VendorBranchList.Row(branch: database.vendorBranches.create(branch))
      }

    case let .delete(id: id):
      try await database.vendorBranches.delete(id)
      return HTTPStatus.ok
    }
  }
}

extension SharedModels.ViewRoute.PurchaseOrderRoute.Search.Request {

  func toDatabaseQuery() throws -> PurchaseOrder.SearchContext {
    switch context {
    case .employee:
      guard let createdForID else {
        throw Abort(.badRequest, reason: "Employee id not provided")
      }
      return .employee(createdForID)
    case .customer:
      guard let customerSearch, !customerSearch.isEmpty else {
        throw Abort(.badRequest, reason: "Customer search string is empty.")
      }
      return .customer(customerSearch)
    case .vendor:
      guard let vendorBranchID else {
        throw Abort(.badRequest, reason: "Vendor branch id not provided.")
      }
      return .vendor(vendorBranchID)
    }
  }
}

extension SharedModels.ViewRoute.SelectContext {
  func toHTML(employees: [Employee]) -> EmployeeSelect {
    switch self {
    case .purchaseOrderForm:
      return .purchaseOrderForm(employees: employees)
    case .purchaseOrderSearch:
      return .purchaseOrderSearch(employees: employees)
    }
  }

  func toHTML(branches: [VendorBranch.Detail]) -> VendorBranchSelect {
    switch self {
    case .purchaseOrderForm:
      return .purchaseOrderForm(branches: branches)
    case .purchaseOrderSearch:
      return .purchaseOrderSearch(branches: branches)
    }
  }
}