opencode-ide-plugin/packages/opencode/webgui/src/lib/messagesStore.ts

/**
 * Centralized message state mutation utilities
 * Eliminates duplicate array cloning logic and type casting from MessagesProvider
 */

import type { Message, WebguiPart, SDKMessage, TextPart } from "../types/messages"

/**
 * Upsert a message (add new or update existing)
 */
export function upsertMessage(messages: Message[], message: Message): Message[] {
  const index = messages.findIndex((m) => m.info.id === message.info.id)

  if (index >= 0) {
    const updated = [...messages]
    updated[index] = message
    return updated
  }

  return [...messages, message]
}

/**
 * Update message info while preserving parts
 */
export function updateMessageInfo(messages: Message[], messageID: string, info: SDKMessage): Message[] {
  const index = messages.findIndex((m) => m.info.id === messageID)

  if (index >= 0) {
    const updated = [...messages]
    updated[index] = { ...updated[index], info }
    return updated
  }

  // Create new message if not found
  return [...messages, { info, parts: [] }]
}

/**
 * Update message with partial data
 */
export function updateMessage(messages: Message[], messageID: string, update: Partial<Message>): Message[] {
  const index = messages.findIndex((m) => m.info.id === messageID)

  if (index < 0) return messages

  const updated = [...messages]
  updated[index] = { ...updated[index], ...update }
  return updated
}

/**
 * Remove a message by ID
 */
export function removeMessage(messages: Message[], messageID: string): Message[] {
  return messages.filter((m) => m.info.id !== messageID)
}

/**
 * Upsert a part in a message (add new or update existing)
 */
export function upsertPart(messages: Message[], messageID: string, part: WebguiPart): Message[] {
  const messageIndex = messages.findIndex((m) => m.info.id === messageID)

  if (messageIndex < 0) return messages

  const updated = [...messages]
  const message = updated[messageIndex]
  const partIndex = message.parts.findIndex((p) => p.id === part.id)

  if (partIndex >= 0) {
    // Update existing part
    const updatedParts = [...message.parts]
    updatedParts[partIndex] = part
    updated[messageIndex] = { ...message, parts: updatedParts }
  } else {
    // Add new part
    updated[messageIndex] = { ...message, parts: [...message.parts, part] }
  }

  return updated
}

/**
 * Apply a text delta to a part (for streaming)
 */
export function applyPartDelta(messages: Message[], messageID: string, part: WebguiPart, delta: string): Message[] {
  if (part.type !== "text") {
    // For non-text parts, just upsert normally
    return upsertPart(messages, messageID, part)
  }

  const messageIndex = messages.findIndex((m) => m.info.id === messageID)

  if (messageIndex < 0) return messages

  const updated = [...messages]
  const message = updated[messageIndex]
  const partIndex = message.parts.findIndex((p) => p.id === part.id)

  if (partIndex >= 0) {
    // Append delta to existing text part
    const existingPart = message.parts[partIndex]
    if (existingPart.type === "text") {
      const updatedParts = [...message.parts]
      updatedParts[partIndex] = {
        ...existingPart,
        text: (existingPart.text || "") + delta,
      }
      updated[messageIndex] = { ...message, parts: updatedParts }
    }
  } else {
    // New part with delta as initial text
    const newPart: TextPart = { ...(part as TextPart), text: delta }
    updated[messageIndex] = { ...message, parts: [...message.parts, newPart] }
  }

  return updated
}

/**
 * Update a specific part in a message
 */
export function updatePart(messages: Message[], messageID: string, partID: string, update: Partial<WebguiPart>): Message[] {
  const messageIndex = messages.findIndex((m) => m.info.id === messageID)

  if (messageIndex < 0) return messages

  const updated = [...messages]
  const message = updated[messageIndex]
  const partIndex = message.parts.findIndex((p) => p.id === partID)

  if (partIndex < 0) return messages

  const updatedParts = [...message.parts]
  updatedParts[partIndex] = { ...updatedParts[partIndex], ...update } as WebguiPart
  updated[messageIndex] = { ...message, parts: updatedParts }

  return updated
}

/**
 * Remove a part from a message
 */
export function removePart(messages: Message[], messageID: string, partID: string): Message[] {
  const messageIndex = messages.findIndex((m) => m.info.id === messageID)

  if (messageIndex < 0) return messages

  const updated = [...messages]
  const message = updated[messageIndex]
  updated[messageIndex] = {
    ...message,
    parts: message.parts.filter((p) => p.id !== partID),
  }

  return updated
}

/**
 * Get messages for a specific session
 */
export function getMessagesBySession(messages: Message[], sessionID: string): Message[] {
  return messages.filter((m) => m.info.sessionID === sessionID)
}