screen_home_ui <- function(id) {
  ns <- NS(id)
  shiny::tagList(
    shiny::uiOutput(ns("filter_row")),
    shiny::div(class = "mb-3",
      shiny::checkboxInput(ns("show_closed"), "Erledigte anzeigen", value = FALSE)
    ),
    shiny::uiOutput(ns("list_cards")),
    shiny::br(),
    shiny::actionButton(ns("new_btn"),
      shiny::tagList(shiny::icon("plus"), " Neue Liste"),
      class = "btn btn-primary w-100",
      style = "min-height:50px"
    )
  )
}

screen_home_server <- function(id, db) {
  moduleServer(id, function(input, output, session) {
    ns          <- session$ns
    reload      <- reactiveVal(0)
    type_filter <- reactiveVal("")
    expanded    <- reactiveVal(integer(0))

    # ---- Filter chips --------------------------------------------------------
    FILTERS <- list(
      list(lbl = "Alle",      val = ""),
      list(lbl = "Einkaufen", val = "shopping"),
      list(lbl = "Aufgaben",  val = "todo"),
      list(lbl = "Projekte",  val = "project")
    )

    output$filter_row <- renderUI({
      cur <- type_filter()
      shiny::div(class = "d-flex gap-2 mb-3 flex-wrap",
        lapply(seq_along(FILTERS), function(i) {
          f      <- FILTERS[[i]]
          active <- identical(cur, f$val)
          shiny::actionButton(ns(paste0("f_", i)), f$lbl,
            class = if (active) "btn btn-primary btn-sm" else "btn btn-outline-secondary btn-sm"
          )
        })
      )
    })

    observe({
      lapply(seq_along(FILTERS), function(i) {
        local({
          li <- i; val <- FILTERS[[li]]$val
          observeEvent(input[[paste0("f_", li)]], type_filter(val), ignoreInit = TRUE)
        })
      })
    })

    # ---- Data ----------------------------------------------------------------
    lists <- reactive({
      reload()
      db_lists_get_all(db, include_closed = isTRUE(input$show_closed))
    })

    filtered <- reactive({
      ls <- lists()
      tf <- type_filter()
      if (!is.null(tf) && tf != "") ls[ls$type == tf, ] else ls
    })

    # ---- Card interactions ---------------------------------------------------
    observeEvent(input$expand, {
      id  <- as.integer(input$expand)
      cur <- expanded()
      expanded(if (id %in% cur) setdiff(cur, id) else c(cur, id))
    })

    observeEvent(input$item_toggle, {
      req(input$item_toggle)
      db_items_set_checked(db,
        id      = as.integer(input$item_toggle$id),
        checked = isTRUE(input$item_toggle$checked)
      )
      reload(reload() + 1L)
    })

    observeEvent(input$add_item, {
      req(input$add_item)
      txt <- trimws(input$add_item$text %||% "")
      if (nchar(txt) == 0) return()
      db_items_insert(db,
        list_id = as.integer(input$add_item$list_id),
        text    = txt
      )
      reload(reload() + 1L)
    })

    observeEvent(input$close_list, {
      req(input$close_list)
      db_lists_close(db, id = as.integer(input$close_list))
      reload(reload() + 1L)
    })

    observeEvent(input$reopen_list, {
      req(input$reopen_list)
      db_lists_reopen(db, id = as.integer(input$reopen_list))
      reload(reload() + 1L)
    })

    observeEvent(input$delete_list, {
      req(input$delete_list)
      db_lists_delete(db, id = as.integer(input$delete_list))
      expanded(setdiff(expanded(), as.integer(input$delete_list)))
      reload(reload() + 1L)
    })

    # ---- Render cards --------------------------------------------------------
    output$list_cards <- renderUI({
      ls  <- filtered()
      exp <- expanded()

      if (nrow(ls) == 0)
        return(shiny::p(class = "text-muted text-center py-4", "Keine Listen vorhanden."))

      lapply(seq_len(nrow(ls)), function(i) {
        row    <- ls[i, ]
        is_exp <- row$id %in% exp
        is_cls <- !is.na(row$closed_at)
        n_tot  <- as.integer(row$item_count %||% 0L)
        n_chk  <- as.integer(row$checked_count %||% 0L)
        items  <- if (is_exp) db_items_by_list(db, row$id) else data.frame()

        type_cls <- switch(row$type,
          shopping = "bg-warning text-dark",
          todo     = "bg-primary",
          project  = "bg-info text-dark",
          "bg-secondary"
        )
        type_lbl <- switch(row$type,
          shopping = "Einkaufen",
          todo     = "Aufgaben",
          project  = "Projekt",
          row$type
        )

        # Header (always visible, tappable to expand)
        hdr <- shiny::div(
          class   = paste("tap-card d-flex justify-content-between align-items-center py-2 px-3",
                          if (is_cls) "bg-light" else "bg-white"),
          style   = "border-bottom: 1px solid rgba(0,0,0,.125);",
          onclick = sprintf("Shiny.setInputValue('%s', %d, {priority:'event'})", ns("expand"), row$id),
          shiny::div(class = "d-flex align-items-center gap-2 overflow-hidden",
            shiny::HTML(sprintf('<span class="badge %s flex-shrink-0">%s</span>', type_cls, type_lbl)),
            shiny::tags$strong(
              class = paste("text-truncate", if (is_cls) "text-muted" else ""),
              row$name
            ),
            if (!is.na(row$t_shirt_size))
              shiny::HTML(sprintf('<span class="badge bg-secondary flex-shrink-0">%s</span>', row$t_shirt_size))
            else NULL
          ),
          shiny::div(class = "d-flex align-items-center gap-2 flex-shrink-0 ms-2",
            shiny::tags$small(class = "text-muted",
              if (n_tot > 0) sprintf("%d/%d", n_chk, n_tot) else "leer"
            ),
            shiny::icon(if (is_exp) "chevron-up" else "chevron-down", class = "text-muted")
          )
        )

        # Body (only when expanded)
        bdy <- if (is_exp) {
          item_rows <- if (nrow(items) > 0) {
            lapply(seq_len(n_tot), function(j) {
              it <- items[j, ]
              shiny::div(
                class = "item-row d-flex align-items-start gap-2 py-2 px-3",
                shiny::tags$input(
                  type    = "checkbox",
                  class   = "form-check-input mt-1 flex-shrink-0",
                  style   = "width:1.1rem;height:1.1rem;cursor:pointer",
                  checked = if (isTRUE(it$checked)) NA else NULL,
                  onclick = sprintf(
                    "Shiny.setInputValue('%s',{id:%d,checked:this.checked},{priority:'event'})",
                    ns("item_toggle"), it$id
                  )
                ),
                shiny::tags$span(
                  class = if (isTRUE(it$checked))
                    "flex-grow-1 text-muted text-decoration-line-through"
                  else "flex-grow-1",
                  it$text
                )
              )
            })
          } else {
            list(shiny::p(class = "text-muted small px-3 py-2 mb-0", "Noch keine Einträge."))
          }

          inp_id <- sprintf("lk_inp_%d", row$id)
          add_row <- shiny::div(class = "d-flex gap-2 px-3 pt-2 pb-1",
            shiny::tags$input(
              type        = "text",
              id          = inp_id,
              class       = "form-control form-control-sm",
              placeholder = "Neuer Eintrag...",
              onkeyup     = sprintf(
                "if(event.key==='Enter'){var v=this.value.trim();if(v){Shiny.setInputValue('%s',{list_id:%d,text:v,ts:Date.now()},{priority:'event'});this.value='';}}",
                ns("add_item"), row$id
              )
            ),
            shiny::tags$button(
              type    = "button",
              class   = "btn btn-outline-primary btn-sm flex-shrink-0",
              onclick = sprintf(
                "(function(i){var v=i.value.trim();if(v){Shiny.setInputValue('%s',{list_id:%d,text:v,ts:Date.now()},{priority:'event'});i.value='';}})(document.getElementById('%s'))",
                ns("add_item"), row$id, inp_id
              ),
              shiny::icon("plus")
            )
          )

          footer_btns <- shiny::div(
            class = "d-flex justify-content-between align-items-center px-3 py-2 bg-light border-top",
            if (!is_cls) {
              shiny::tags$button(
                type    = "button",
                class   = "btn btn-success btn-sm",
                onclick = sprintf("Shiny.setInputValue('%s',%d,{priority:'event'})", ns("close_list"), row$id),
                shiny::icon("check"), " Erledigt"
              )
            } else {
              shiny::tags$button(
                type    = "button",
                class   = "btn btn-outline-secondary btn-sm",
                onclick = sprintf("Shiny.setInputValue('%s',%d,{priority:'event'})", ns("reopen_list"), row$id),
                shiny::icon("undo"), " Wieder öffnen"
              )
            },
            shiny::tags$button(
              type    = "button",
              class   = "btn btn-outline-danger btn-sm",
              onclick = sprintf(
                "if(confirm('Liste und alle Einträge löschen?'))Shiny.setInputValue('%s',%d,{priority:'event'})",
                ns("delete_list"), row$id
              ),
              shiny::icon("trash")
            )
          )

          shiny::div(
            shiny::tagList(item_rows),
            add_row,
            footer_btns
          )
        } else NULL

        shiny::div(class = "card mb-2 shadow-sm", hdr, bdy)
      })
    })

    # ---- New list modal ------------------------------------------------------
    observeEvent(input$new_btn, {
      shiny::showModal(shiny::modalDialog(
        title  = "Neue Liste",
        footer = shiny::tagList(
          shiny::modalButton("Abbrechen"),
          shiny::actionButton(ns("confirm_new"), "Erstellen", class = "btn-primary")
        ),
        shiny::textInput(ns("new_name"), "Name *"),
        shiny::selectInput(ns("new_type"), "Typ",
          choices  = c("Einkaufen" = "shopping", "Aufgaben" = "todo", "Projekt" = "project"),
          selected = "shopping"
        ),
        shiny::uiOutput(ns("new_extra_ui"))
      ))
    })

    output$new_extra_ui <- renderUI({
      req(input$new_type)
      if (input$new_type == "project") {
        shiny::selectInput(ns("new_size"), "Aufwand (T-Shirt-Größe)",
          choices  = c("XS", "S", "M", "L", "XL"),
          selected = "M"
        )
      }
    })

    observeEvent(input$confirm_new, {
      name <- trimws(input$new_name %||% "")
      if (nchar(name) == 0) {
        shiny::showNotification("Bitte einen Namen eingeben.", type = "warning", duration = 3)
        return()
      }
      t_size <- if (!is.null(input$new_type) && input$new_type == "project")
        input$new_size else NA
      db_lists_insert(db,
        name         = name,
        type         = input$new_type,
        t_shirt_size = t_size
      )
      shiny::removeModal()
      reload(reload() + 1L)
    })
  })
}