CREATE TABLE messages (
    id                  BYTEA       NOT NULL CHECK(length(id) = 26),
    channel_id          BYTEA       NOT NULL CHECK(length(channel_id) = 26),
    guild_id            BYTEA       CHECK(length(guild_id) = 26),  -- nullable for DMs
    author_id           BYTEA       NOT NULL CHECK(length(author_id) = 26),

    -- Message content and metadata
    content             TEXT        NOT NULL DEFAULT '',
    timestamp           TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    edited_timestamp    TIMESTAMPTZ,
    tts                 BOOLEAN     NOT NULL DEFAULT FALSE,

    -- Mentions and embeds (as JSON for flexibility)
    mentions            BYTEA[],  -- array of user IDs (could also be TEXT[] if using base58)
    mention_everyone    BOOLEAN     NOT NULL DEFAULT FALSE,
    embeds              JSONB       NOT NULL DEFAULT '[]'::jsonb,
    attachments         BYTEA[],

    -- Reply/reference data (optional)
    reply_message_id    BYTEA       CHECK(length(reply_message_id) = 26),
    application_id      BYTEA       CHECK(length(application_id) = 26),  -- for slash commands

    -- System/interaction message type
    message_type        INTEGER     NOT NULL DEFAULT 0,  -- 0 = default, 1 = reply, 2 = gateway ping, etc.

    -- Thread support
    thread_name         TEXT,
    auto_archive_duration INTEGER,  -- minutes (360, 1440, 4320, 10080)

    -- Audit & integrity
    created_at          TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at          TIMESTAMPTZ NOT NULL DEFAULT NOW(),

    PRIMARY KEY (id)
);

-- Indexes for common query patterns
CREATE INDEX idx_messages_channel_id ON messages (channel_id);
CREATE INDEX idx_messages_channel_id_timestamp ON messages (channel_id, timestamp DESC);
CREATE INDEX idx_messages_author_id ON messages (author_id);
CREATE INDEX idx_messages_guild_id ON messages (guild_id) WHERE guild_id IS NOT NULL;
CREATE INDEX idx_messages_reference_message_id ON messages (reply_message_id);
CREATE INDEX idx_messages_timestamp ON messages (timestamp DESC);