/**
 * Shared shapes + wording for the audit trail (quote / order / delivery
 * note history). Rows are written by the PB hook
 * pocketbase/pb_hooks/audit_log.pb.js and read by
 * src/lib/server/audit-log-service.ts. Safe to import from client
 * components.
 */

export type AuditParentType = "quote" | "order" | "delivery_note";

export type AuditChange = {
  field: string;
  from: unknown;
  to: unknown;
  /** Append-only text field: `to` holds just the appended part. */
  appended?: boolean;
};

export type AuditEntry = {
  id: string;
  created: string;
  collection: string;
  recordId: string;
  action: string;
  label: string;
  changes: AuditChange[];
  actorName: string;
  actorEmail: string;
  source: string;
  /**
   * For price / markup edits on a quote: the number of the most recent
   * quote PDF generated before this edit (1-based), or null when no PDF
   * existed yet. Drives the "changed after PDF #n" flag.
   */
  afterPdf: number | null;
};

export type AuditSummary = {
  pdfCount: number;
  priceChanges: number;
  markupChanges: number;
  /** Price / markup edits made after at least one PDF went out. */
  changesAfterPdf: number;
  editors: Array<{ name: string; count: number }>;
};

export type AuditTrail = {
  /** False when the audit_log collection hasn't been created yet. */
  enabled: boolean;
  entries: AuditEntry[];
  summary: AuditSummary;
};

export const PRICE_FIELDS = new Set(["cost_price", "selling_price"]);
export const MARKUP_FIELDS = new Set(["markup", "markup_percent"]);
export const MONEY_FIELDS = new Set(["cost_price", "selling_price", "total_amount"]);

const FIELD_LABELS: Record<string, string> = {
  cost_price: "Cost price",
  selling_price: "Selling price",
  markup: "Markup",
  markup_percent: "Markup",
  quantity: "Qty",
  order_qty: "Supplier qty",
  description: "Description",
  po_description: "PO description",
  quote_description: "Quote description",
  supplier: "Supplier",
  status: "Status",
  item_status: "Status",
  customer: "Customer",
  company: "Company",
  company_letterhead: "Letterhead",
  claimed_by: "Claimed by",
  approved_by: "Approved by",
  notes: "Notes",
  quote_notes: "Quote notes",
  is_processed: "Processed",
  in_stock: "In stock",
  order_number: "Order number",
  quote_number: "Quote number",
  delivery_note_number: "Delivery note",
  customer_po: "Customer PO",
  rfq_number: "RFQ number",
  quote: "Linked quote",
  order: "Linked order",
  rep: "Rep",
  invoiced: "Invoiced",
  "order_item_details.invoice": "Invoice",
  "order_item_details.print": "Printed",
  customer_invoice_number: "Invoice number",
  qty_collected: "Qty collected",
  qty_delivered: "Qty delivered",
  qty_invoiced: "Qty invoiced",
  sku: "SKU",
  unit: "Unit",
  validity_days: "Validity (days)",
  is_no_quote: "No-quote letter",
};

export function fieldLabel(field: string): string {
  if (FIELD_LABELS[field]) return FIELD_LABELS[field];
  const leaf = field.split(".").pop() || field;
  const words = leaf.replace(/_/g, " ");
  return words.charAt(0).toUpperCase() + words.slice(1);
}

// Same format as `formatCurrency` in pb-helpers (not imported: that
// module pulls in the browser PB client).
function formatMoney(value: number): string {
  return new Intl.NumberFormat("en-ZA", { style: "currency", currency: "ZAR" }).format(value);
}

/** Human-readable rendering of one side of a change. */
export function formatAuditValue(field: string, value: unknown): string {
  if (value === null || value === undefined || value === "") return "—";
  if (typeof value === "boolean") return value ? "Yes" : "No";
  if (typeof value === "number") {
    if (MONEY_FIELDS.has(field)) return formatMoney(value);
    if (MARKUP_FIELDS.has(field)) return `${value}%`;
    return String(value);
  }
  if (Array.isArray(value)) return value.length ? value.join(", ") : "—";
  if (typeof value === "object") {
    const obj = value as Record<string, unknown>;
    if (field === "order_item_details.invoice" && typeof obj.number === "string") {
      return obj.date ? `${obj.number} (${String(obj.date).slice(0, 10)})` : obj.number;
    }
    if (field === "order_item_details.print") return obj.printed ? "Yes" : "No";
    return JSON.stringify(value);
  }
  const text = String(value);
  // Status slugs read better as words.
  if (field === "status" || field === "item_status") return text.replace(/_/g, " ");
  return text;
}

const ACTION_VERBS: Record<string, Record<string, string>> = {
  quotes: { create: "Created the quote", update: "Updated the quote", delete: "Deleted the quote" },
  quote_items: { create: "Added line", update: "Edited line", delete: "Removed line" },
  quote_attachments: { attachment_added: "Attached", delete: "Removed attachment" },
  orders: { create: "Created the order", update: "Updated the order", delete: "Deleted the order" },
  order_items: { create: "Added line", update: "Edited line", delete: "Removed line" },
  delivery_notes: {
    create: "Created the delivery note",
    update: "Updated the delivery note",
    delete: "Deleted the delivery note",
  },
};

/** One-line headline for an entry, e.g. `Edited line "M16 hex bolt"`. */
export function describeAuditEntry(entry: Pick<AuditEntry, "collection" | "action" | "label">): string {
  if (entry.action === "pdf_generated") return "Generated the quote PDF";
  const verb = ACTION_VERBS[entry.collection]?.[entry.action] ?? `${entry.action} ${entry.collection}`;
  const isHeader = entry.collection === "quotes" || entry.collection === "orders" || entry.collection === "delivery_notes";
  return !isHeader && entry.label ? `${verb} "${entry.label}"` : verb;
}

export const SOURCE_LABELS: Record<string, string> = {
  web: "Dashboard",
  api: "Automation",
  n8n: "n8n",
  agent: "Agent API",
  mcp: "MCP agent",
  server: "Server",
  system: "System",
};