function normalizeEntry(value) {
  if (typeof value === "string")
    return value.length > 0 ? { type: "text", text: value } : null

  if (!value || typeof value !== "object") return null

  var type = String(value.type || value.kind || "")
  if (type === "text") {
    var text = String(value.text || "")
    return text.length > 0 ? { type: "text", text: text } : null
  }

  if (type === "image") {
    var path = String(value.path || "")
    if (!path) return null
    return {
      type: "image",
      path: path,
      mime: String(value.mime || "image/png")
    }
  }

  return null
}

function entryKey(entry) {
  if (!entry) return ""
  if (entry.type === "image") return "image:" + String(entry.path || "")
  return "text:" + String(entry.text || "")
}

function parseHistory(raw) {
  try {
    var parsed = JSON.parse(String(raw || "[]"))
    var next = []
    if (!Array.isArray(parsed)) return next

    for (var i = 0; i < parsed.length; i++) {
      var entry = normalizeEntry(parsed[i])
      if (entry) next.push(entry)
    }
    return next
  } catch (e) {
    return []
  }
}

function addEntry(history, entry, limit) {
  var normalized = normalizeEntry(entry)
  var max = limit === undefined || limit === null ? 100 : Number(limit)
  if (isNaN(max)) max = 100
  max = Math.max(0, max)
  if (!normalized) return Array.isArray(history) ? history.slice(0, max) : []
  if (max === 0) return []

  var key = entryKey(normalized)
  var next = [normalized]
  var values = Array.isArray(history) ? history : []

  for (var i = 0; i < values.length && next.length < max; i++) {
    var existing = normalizeEntry(values[i])
    if (!existing || entryKey(existing) === key) continue
    next.push(existing)
  }

  return next
}

function parseEntryJson(line) {
  var raw = String(line || "").trim()
  if (!raw) return null
  try { return normalizeEntry(JSON.parse(raw)) } catch (e) { return null }
}

function searchableText(entry) {
  if (!entry) return ""
  if (entry.type === "image") return "image " + String(entry.mime || "")
  return String(entry.text || "")
}

function previewText(entry) {
  if (!entry) return ""
  if (entry.type === "image") return "Image"
  return String(entry.text || "").replace(/\s+/g, " ")
}

function displayRows(history, query, limit) {
  var values = Array.isArray(history) ? history : []
  var needle = String(query || "").trim().toLowerCase()
  var max = limit === undefined || limit === null ? 50 : Number(limit)
  if (isNaN(max)) max = 50
  max = Math.max(0, max)
  if (max === 0) return []

  var rows = []

  for (var i = 0; i < values.length; i++) {
    var entry = normalizeEntry(values[i])
    if (!entry) continue
    if (needle && searchableText(entry).toLowerCase().indexOf(needle) < 0) continue

    var isImage = entry.type === "image"
    rows.push({
      entryType: entry.type,
      fullText: isImage ? "" : String(entry.text || ""),
      previewText: previewText(entry),
      previewImage: isImage ? String(entry.path || "") : "",
      path: isImage ? String(entry.path || "") : "",
      mime: isImage ? String(entry.mime || "image/png") : "text/plain",
      index: rows.length
    })
    if (rows.length >= max) break
  }

  return rows
}

if (typeof module !== "undefined") {
  module.exports = {
    normalizeEntry: normalizeEntry,
    entryKey: entryKey,
    parseHistory: parseHistory,
    addEntry: addEntry,
    parseEntryJson: parseEntryJson,
    searchableText: searchableText,
    previewText: previewText,
    displayRows: displayRows
  }
}