# module_buchungen.R

buchungenUI <- function(id) {
  ns <- NS(id)
  tagList(
    useShinyjs(), 
    h3("Hauptbuchungen"),
    reactableOutput(ns("buchungen_table")),
    hr(),
    h3("Details / Gegenbuchungen"),
    reactableOutput(ns("details_table")),
    br(),
    actionBttn(ns("add_trans"), "Transaktion hinzu", size = "sm", style = "material-flat", color = "warning"),
    actionBttn(ns("del_trans"), "Transaktion Löschen", size = "sm", style = "material-flat", color = "danger"),
    actionBttn(ns("add_detail"), "Detail hinzu", size = "sm", style = "material-flat", color = "success"),
    
    # Das UI-Element des Moduls (auch wenn es leer ist)
    postingModuleUI(ns("posting_modal"))
  )
}

buchungenServer <- function(id, conn,  aktiver_filter = reactive("alle")) {
  moduleServer(id, function(input, output, session) {
    ns <- session$ns
    
    # * Reactive Variablen ----
    postings_data      <- reactiveVal(read_buch_tabelle(conn))
    details_data       <- reactiveVal(NULL)
    selected_trans_id  <- reactiveVal(NULL)
    current_main_idx   <- reactiveVal(NULL)
    reset_trigger      <- reactiveVal(0)  # ← neu: erzwingt Re-render mit Filter-Reset
    modal_trigger      <- reactiveVal(list(post_id = NULL, counter = 0))
    highlighted_valuta <- reactiveVal(NULL)
    
    
    update_db_trigger <- postingModuleServer("posting_modal", conn, selected_trans_id, modal_trigger)
    
    gefilterte_daten <- reactive({
      d <- postings_data()
      switch(aktiver_filter(),
        "giro"  = d |> filter(grepl("0130", account_name)),
        "monat" = d |> filter(
          floor_date(as.Date(valuta), "month") == floor_date(Sys.Date(), "month")
          
        ),
        d
      )
    })
    
    observeEvent(aktiver_filter(), {
      current_main_idx(NULL)
      selected_trans_id(NULL)
      details_data(NULL)
    })
    
    # * Haupttabelle rendern ----
    output$buchungen_table <- renderReactable({
      reset_trigger()
      f_reactable(
        daten           = gefilterte_daten(),  # ← geändert
        coldefs         = coldef_entries_tabelle,
        selection       = "single",
        hoehe           = "60vh",
        defaultSelected = current_main_idx(),
        highlight_valuta = highlighted_valuta()
      )
    })
    
    # * Details-Tabelle laden ----
    sel_details <- reactive(getReactableState("buchungen_table", "selected"))
    observeEvent(sel_details(), ignoreInit = TRUE, {
      req(sel_details())
      highlighted_valuta(gefilterte_daten()[sel_details(), "valuta"])
      current_main_idx(sel_details())
      t_id <- gefilterte_daten()[sel_details(), "entry_id"] |> pull()  # ← geändert
      selected_trans_id(t_id)
      details_data(read_buch_tabelle(conn, trans_id = t_id))
    })
    output$details_table <- renderReactable({
      req(details_data())
      f_reactable(
        details_data(),
        coldefs   = coldef_entries_tabelle,
        selection = "single",
        hoehe     = NULL
      )
    })
    
    # * Detail hinzufügen ----
    observeEvent(input$add_detail, {
      req(selected_trans_id())
      modal_trigger(list(post_id = NULL, counter = modal_trigger()$counter + 1))
    })
    
    # * Detail editieren (Klick auf Detail-Tabelle) ----
    sel_detail <- reactive(getReactableState("details_table", "selected"))
    
    observeEvent(sel_detail(), ignoreInit = TRUE, {
      p_id <- details_data()$id[sel_detail()]
      modal_trigger(list(post_id = p_id, counter = modal_trigger()$counter + 1))
    })
    
    # * DB-Update durch Modal ----
    observeEvent(update_db_trigger(), ignoreInit = TRUE, {
      req(selected_trans_id())
      details_data(read_buch_tabelle(conn, trans_id = selected_trans_id()))
      postings_data(read_buch_tabelle(conn))
      # Kein Re-render nötig – Filter/Sortierung bleibt erhalten
      updateReactable("buchungen_table", data = postings_data())
    })
    
    # * Neue Transaktion ----
    observeEvent(input$add_trans, {
      new_t_id <- max_id(conn, "entries") + 1
      dbxInsert(conn, "entries", data.frame(id = new_t_id))
      p_id1 <- max_id(conn, "postings") + 1
      p_id2 <- p_id1 + 1
      dbxInsert(conn, "postings", data.frame(
        id       = c(p_id1, p_id2),
        entry_id = c(new_t_id, new_t_id),
        amount   = c(0, 0),
        account_id = c(0, 0),
        valuta   = c(Sys.Date(), Sys.Date())
      ))
      ## ** Daten aktualisieren ----
      postings_data(read_buch_tabelle(conn))
      selected_trans_id(new_t_id)
      details_data(read_buch_tabelle(conn, trans_id = new_t_id))
      ## ** Index in neuen Daten suchen ----
      neue_zeile <- which(postings_data()$id == p_id1)
      current_main_idx(neue_zeile)
      ## ** Re-render erzwingen → Filter wird zurückgesetzt, neue Zeile selektiert ----
      reset_trigger(isolate(reset_trigger()) + 1)
      scroll_to_row(ns("buchungen_table"), neue_zeile)
    })
    
    # * Transaktion löschen ----
    observeEvent(input$del_trans, ignoreInit = TRUE, {
      req(selected_trans_id())
      dbxDelete(conn, "postings", where = data.frame(entry_id = selected_trans_id()))
      dbxDelete(conn, "entries",  where = data.frame(id = selected_trans_id()))
      postings_data(read_buch_tabelle(conn))
      current_main_idx(NULL)
      selected_trans_id(NULL)
      details_data(NULL)
      updateReactable("buchungen_table", data = postings_data())
      # details_table re-rendert automatisch weil details_data(NULL) → req() schlägt fehl
    })
  })
}