Protocol and Message Utilities

/**
 * Identifies if message was sent by container runtime
 * @param message - Message with type property
 * @returns true if message type is MessageType.Operation
 */
function isRuntimeMessage(message: {type: string}): boolean;

/**
 * Determines if message can be coalesced by relay service
 * @param message - Sequenced or unsequenced document message
 * @returns true if message can be coalesced (NoOp or Accept messages)
 */
function canBeCoalescedByService(
  message: ISequencedDocumentMessage | IDocumentMessage
): boolean;

import { 
  isRuntimeMessage, 
  canBeCoalescedByService 
} from "@fluidframework/driver-utils";

// Filter runtime messages
const messages = await getMessages();
const runtimeMessages = messages.filter(isRuntimeMessage);

// Check if messages can be coalesced
const coalescableMessages = messages.filter(canBeCoalescedByService);
console.log(`${coalescableMessages.length} messages can be coalesced`);

/**
 * Converts flat git tree structure to hierarchical snapshot tree
 * @param flatTree - Flat git tree from service
 * @param blobsShaToPathCache - Optional cache mapping blob SHAs to paths
 * @param removeAppTreePrefix - Whether to remove .app/ prefix from paths
 * @returns Hierarchical snapshot tree with extended metadata
 */
function buildGitTreeHierarchy(
  flatTree: IGitTree,
  blobsShaToPathCache?: Map<string, string>,
  removeAppTreePrefix?: boolean
): ISnapshotTreeEx;

/**
 * Returns git file mode string for summary objects
 * @param value - Summary object (tree or blob)
 * @returns Git file mode (FileMode.File or FileMode.Directory)
 */
function getGitMode(value: SummaryObject): string;

/**
 * Returns git object type for summary objects
 * @param value - Summary object (tree or blob)
 * @returns "blob" for files, "tree" for directories
 */
function getGitType(value: SummaryObject): "blob" | "tree";

import { 
  buildGitTreeHierarchy, 
  getGitMode, 
  getGitType 
} from "@fluidframework/driver-utils";

// Convert flat git tree to hierarchical structure
const flatGitTree: IGitTree = {
  entries: [
    { path: ".app/data.json", sha: "abc123", mode: "100644", type: "blob" },
    { path: ".app/config/settings.json", sha: "def456", mode: "100644", type: "blob" },
    { path: ".protocol/quorum.json", sha: "ghi789", mode: "100644", type: "blob" }
  ]
};

const blobCache = new Map<string, string>();
const hierarchicalTree = buildGitTreeHierarchy(
  flatGitTree, 
  blobCache, 
  true // Remove .app prefix
);

// Get git metadata for summary objects
const summaryBlob = { type: SummaryType.Blob, content: "data" };
const summaryTree = { type: SummaryType.Tree, tree: {} };

console.log(getGitMode(summaryBlob)); // "100644"
console.log(getGitType(summaryBlob)); // "blob"
console.log(getGitMode(summaryTree)); // "040000" 
console.log(getGitType(summaryTree)); // "tree"

import { 
  isRuntimeMessage, 
  canBeCoalescedByService 
} from "@fluidframework/driver-utils";

class MessageProcessor {
  processMessageBatch(messages: ISequencedDocumentMessage[]): ProcessedMessages {
    const runtimeMessages: ISequencedDocumentMessage[] = [];
    const systemMessages: ISequencedDocumentMessage[] = [];
    const coalescableMessages: ISequencedDocumentMessage[] = [];
    
    for (const message of messages) {
      if (isRuntimeMessage(message)) {
        runtimeMessages.push(message);
      } else {
        systemMessages.push(message);
      }
      
      if (canBeCoalescedByService(message)) {
        coalescableMessages.push(message);
      }
    }
    
    return {
      runtime: runtimeMessages,
      system: systemMessages,
      coalescable: coalescableMessages,
      total: messages.length
    };
  }
  
  optimizeMessageBatch(messages: ISequencedDocumentMessage[]): ISequencedDocumentMessage[] {
    // Remove coalescable messages that can be optimized away
    return messages.filter(message => !canBeCoalescedByService(message));
  }
}

interface ProcessedMessages {
  runtime: ISequencedDocumentMessage[];
  system: ISequencedDocumentMessage[];
  coalescable: ISequencedDocumentMessage[];
  total: number;
}

import { 
  buildGitTreeHierarchy, 
  getGitMode, 
  getGitType 
} from "@fluidframework/driver-utils";

class GitTreeConverter {
  convertToSnapshot(
    gitTree: IGitTree, 
    shouldRemoveAppPrefix: boolean = false
  ): ConversionResult {
    const blobPathCache = new Map<string, string>();
    
    const snapshotTree = buildGitTreeHierarchy(
      gitTree, 
      blobPathCache, 
      shouldRemoveAppPrefix
    );
    
    return {
      tree: snapshotTree,
      blobPaths: blobPathCache,
      stats: this.calculateStats(gitTree)
    };
  }
  
  generateGitTreeFromSummary(summary: ISummaryTree): GitTreeEntry[] {
    const entries: GitTreeEntry[] = [];
    this.walkSummaryTree(summary, "", entries);
    return entries;
  }
  
  private walkSummaryTree(
    tree: ISummaryTree, 
    basePath: string, 
    entries: GitTreeEntry[]
  ): void {
    for (const [name, value] of Object.entries(tree.tree)) {
      const fullPath = basePath ? `${basePath}/${name}` : name;
      
      entries.push({
        path: fullPath,
        mode: getGitMode(value),
        type: getGitType(value),
        sha: this.generateSha(value) // Would need actual SHA calculation
      });
      
      if (value.type === SummaryType.Tree) {
        this.walkSummaryTree(value, fullPath, entries);
      }
    }
  }
  
  private calculateStats(gitTree: IGitTree): GitTreeStats {
    const stats: GitTreeStats = {
      totalEntries: gitTree.entries.length,
      blobCount: 0,
      treeCount: 0,
      maxDepth: 0
    };
    
    for (const entry of gitTree.entries) {
      if (entry.type === "blob") {
        stats.blobCount++;
      } else if (entry.type === "tree") {
        stats.treeCount++;
      }
      
      const depth = entry.path.split('/').length;
      stats.maxDepth = Math.max(stats.maxDepth, depth);
    }
    
    return stats;
  }
  
  private generateSha(value: SummaryObject): string {
    // Simplified SHA generation - in practice would use proper hashing
    return `sha-${JSON.stringify(value).length}`;
  }
}

interface ConversionResult {
  tree: ISnapshotTreeEx;
  blobPaths: Map<string, string>;
  stats: GitTreeStats;
}

interface GitTreeStats {
  totalEntries: number;
  blobCount: number;
  treeCount: number;
  maxDepth: number;
}

interface GitTreeEntry {
  path: string;
  mode: string;
  type: "blob" | "tree";
  sha: string;
}

import { 
  isRuntimeMessage, 
  canBeCoalescedByService 
} from "@fluidframework/driver-utils";

class MessageStreamProcessor {
  async processMessageStream(
    messageStream: IStream<ISequencedDocumentMessage[]>,
    onRuntimeMessage: (message: ISequencedDocumentMessage) => void,
    onSystemMessage: (message: ISequencedDocumentMessage) => void
  ): Promise<void> {
    while (true) {
      const result = await messageStream.read();
      
      if (result.done) {
        break;
      }
      
      if (result.value) {
        for (const message of result.value) {
          if (isRuntimeMessage(message)) {
            onRuntimeMessage(message);
          } else {
            onSystemMessage(message);
          }
        }
      }
    }
  }
  
  createOptimizedMessageStream(
    sourceStream: IStream<ISequencedDocumentMessage[]>
  ): IStream<ISequencedDocumentMessage[]> {
    const optimizedQueue = new Queue<ISequencedDocumentMessage[]>();
    
    // Process source stream in background
    this.processSourceStream(sourceStream, optimizedQueue);
    
    return optimizedQueue;
  }
  
  private async processSourceStream(
    source: IStream<ISequencedDocumentMessage[]>,
    output: Queue<ISequencedDocumentMessage[]>
  ): Promise<void> {
    try {
      while (true) {
        const result = await source.read();
        
        if (result.done) {
          output.pushDone();
          break;
        }
        
        if (result.value) {
          // Filter out coalescable messages for optimization
          const optimizedBatch = result.value.filter(
            message => !canBeCoalescedByService(message)
          );
          
          if (optimizedBatch.length > 0) {
            output.pushValue(optimizedBatch);
          }
        }
      }
    } catch (error) {
      output.pushError(error);
    }
  }
}