import { ui_locales } from "@ui/ui_template_locale";

export type FileSlot = "csv" | "las_laz" | "prj" | "tfw" | "tif" | "dxf";
export type UploadStatus = "pending" | "uploading" | "completed" | "failed";

export interface SlotConfig {
  slot: FileSlot;
  labelKey: keyof typeof ui_locales;
  icon: string;
  extensions: readonly string[];
  isRequired: boolean;
}

export interface FileSlotState extends SlotConfig {
  file?: File;
  uploadSessionId?: string;
  uploadStatus: UploadStatus;
  progressBytes: number;
  speedMbs: number;
  etaSeconds: number | null;
  error?: string;
}

export interface StoredUploadSession {
  key: string;
  projectId: string;
  slot: FileSlot;
  fileName: string;
  fileSize: number;
  uploadSessionId: string;
  chunkSizeBytes: number;
  totalChunks: number;
  completedChunks: number;
  updatedAt: number;
}

const SLOT_CONFIGS: readonly SlotConfig[] = [
  {
    slot: "csv",
    labelKey: "B03_File_Slot_PlannedRoute",
    icon: "⌁",
    extensions: [".csv"],
    isRequired: true,
  },
  {
    slot: "las_laz",
    labelKey: "B03_File_Slot_PointCloud",
    icon: "●",
    extensions: [".las", ".laz"],
    isRequired: true,
  },
  {
    slot: "prj",
    labelKey: "B03_File_Slot_Projection",
    icon: "◇",
    extensions: [".prj"],
    isRequired: true,
  },
  {
    slot: "tfw",
    labelKey: "B03_File_Slot_RasterCoord",
    icon: "□",
    extensions: [".tfw"],
    isRequired: true,
  },
  {
    slot: "tif",
    labelKey: "B03_File_Slot_TerrainDem",
    icon: "▧",
    extensions: [".tif"],
    isRequired: false,
  },
];

export function getExtension(fileName: string): string {
  const index = fileName.lastIndexOf(".");
  return index >= 0 ? fileName.slice(index).toLowerCase() : "";
}

export function formatBytes(bytes: number): string {
  const gb = bytes / 1024 / 1024 / 1024;
  if (gb >= 1) return `${gb.toFixed(2)} GB`;
  return `${(bytes / 1024 / 1024).toFixed(2)} MB`;
}

export function formatEta(seconds: number | null): string {
  if (seconds === null || !Number.isFinite(seconds)) return "-";
  if (seconds < 60) return `${Math.ceil(seconds)}s`;
  return `${Math.ceil(seconds / 60)}m`;
}

export function makeSessionKey(projectId: string, file: File): string {
  return `b03_upload_${projectId}_${file.name}_${file.size}`;
}

export function initializeSlots(): Map<FileSlot, FileSlotState> {
  const map = new Map<FileSlot, FileSlotState>();
  for (const config of SLOT_CONFIGS) {
    map.set(config.slot, {
      ...config,
      uploadStatus: "pending",
      progressBytes: 0,
      speedMbs: 0,
      etaSeconds: null,
    });
  }
  return map;
}

export function createFileCardTemplate(): HTMLTemplateElement {
  const template = document.createElement("template");
  template.id = "file-card-template";
  template.innerHTML = `
    <article class="b03-file__card b03-file__card--empty">
      <div class="b03-file__card-header">
        <span class="b03-file__card-icon" aria-hidden="true"></span>
        <div class="b03-file__card-heading">
          <strong class="b03-file__card-label"></strong>
          <span class="b03-file__card-ext"></span>
        </div>
        <div class="b03-file__card-badge-container"></div>
        <button class="b03-file__card-remove" type="button"></button>
      </div>
      <div class="b03-file__card-content">
        <button class="b03-file__card-select" type="button"></button>
        <input class="b03-file__slot-input" type="file" />
        <div class="b03-file__file-info">
          <span class="b03-file__file-name"></span>
          <span class="b03-file__file-size"></span>
        </div>
        <div class="b03-file__progress-section">
          <div class="b03-file__progress-bar-container">
            <div class="b03-file__progress-bar"></div>
          </div>
          <div class="b03-file__progress-info">
            <span class="b03-file__progress-bytes"></span>
            <span class="b03-file__progress-speed"></span>
            <span class="b03-file__progress-eta"></span>
          </div>
        </div>
        <div class="b03-file__error-message" role="alert"></div>
      </div>
    </article>
  `;
  return template;
}