Discord channel history search with keyword filtering and image detection for /pin command.

Search Functions

Utility module: src/utils/messageSearch.js

Core functions:

• findLastPinCommand(channel, maxMessages) – Locates last /pin command execution
• searchMessagesAfter(channel, afterMessageId, maxMessages) – Fetches messages after reference point
• generateKeywordVariants(keyword) – Creates singular/plural variations
• messageMatchesKeywords(message, keywordVariants) – Tests message content against keywords
• messageHasImages(message) – Detects Midjourney upscaled images
• extractImageMessageIds(channel, keyword, afterMessage, maxResults) – Combines all functions for /pin command

Last Pin Command Search

Purpose:
Finds most recent /pin command execution in channel.

Algorithm:

1. Fetch messages in batches of 100 (Discord limit)
2. Iterate through messages chronologically
3. Check for interaction command name = "pin"
4. Return first matching message
5. Continue pagination if not found

Pagination:

• Uses before parameter for backward pagination
• Maximum 500 messages searched by default
• 100ms delay between batches to prevent rate limiting

Return value:

• Message object if found
• null if no /pin command found in range

Use case:
Establishes search starting point for /pin command.

Message Pagination

Backward pagination:
Uses before parameter to fetch older messages.

Forward pagination:
Uses after parameter to fetch newer messages.

Batch size:
100 messages per fetch (Discord maximum).

Rate limiting:
100ms delay between fetches to prevent API throttling.

Continuation:
Stops when:

• Batch returns zero messages
• Maximum message limit reached
• All available messages fetched

Keyword Variant Generation

Purpose:
Automatically handles singular/plural forms.

Algorithm:

1. Start with lowercase keyword
2. If doesn’t end with ‘s’: Add plural form (keyword + ‘s’)
3. If ends with ‘s’ and length > 1: Add singular form (keyword – ‘s’)

Examples:

• "cat" → ["cat", "cats"]
• "dogs" → ["dogs", "dog"]
• "mouse" → ["mouse", "mouses"] (Note: Not linguistically perfect)

Limitations:

• Simple suffix-based logic
• No irregular plural handling (mouse/mice, child/children)
• No stemming or lemmatization

Keyword Matching

Search locations:

• Message content (message.content)
• Embed descriptions (embed.description)
• Embed titles (embed.title)
• Attachment names (attachment.name)

Match algorithm:

1. Collect all text from search locations
2. Join into single lowercase string
3. Test each keyword variant with includes()
4. Return true if any variant matches

Match type:
Substring match (case-insensitive).

Examples:

• Keyword "cat" matches "I love cats"
• Keyword "dog" matches "doghouse"
• Keyword "art" matches "artificial"

Image Detection

Detection criteria:
Messages must contain:

1. Text "- Image #" in message content (Midjourney format)
2. Actual image attachment or embed

Midjourney format:

• Upscaled images contain "- Image #1", "- Image #2", etc.
• 4-image grid previews do not contain "- Image #"

Image sources:

1. Attachments with image/* content type
2. Embed image property
3. Embed thumbnail property

Exclusion:
4-image grids excluded automatically by "- Image #" requirement.

Purpose:
Ensures found messages contain single upscaled images suitable for pinning.

Message ID Extraction

Purpose:
Main function for /pin command – combines all search capabilities.

Parameters:

• channel – Discord channel to search
• keyword – Search term
• afterMessage – Optional reference message (last /pin command)
• maxResults – Maximum message IDs to return (default 10)

Algorithm:

1. Generate keyword variants (singular/plural)
2. Determine search scope:
   • With afterMessage: Search messages after that point
   • Without afterMessage: Search 100 most recent messages
3. Iterate through messages
4. For each message:
   • Check if has images (Midjourney upscaled format)
   • Check if matches keywords
   • Add message ID to results if both true
5. Stop when maxResults reached or messages exhausted

Return value:
Array of message IDs (strings) matching criteria.

Search limits:

• Maximum 10 results by default (customizable)
• Searches up to 1000 messages when afterMessage provided
• Searches 100 messages when no afterMessage

Search Scope Determination

With previous /pin command:

1. /pin finds last /pin execution
2. Searches messages posted after that point
3. Useful for finding new images since last pinning session

Without previous /pin command:

1. Searches 100 most recent messages
2. Useful for first-time usage in channel

Message ordering:
Messages processed chronologically from reference point forward.

Error Handling

Search failures:

• Logged to console
• Returns empty array
• Does not throw errors

Pagination failures:

• Returns messages collected so far
• Logged to console

Rate limiting:
Built-in delays prevent Discord API rate limits.

Performance

Fetch operations:

• Minimum 1 fetch (100 messages)
• Maximum 10 fetches (1000 messages)
• 100ms delay between fetches = 1 second maximum delay

Processing:

• Linear iteration through messages
• No indexing or caching
• Real-time search on command execution

Memory:
Messages stored in array during search, released after completion.