
-- C Nostr Relay Database Schema
\
-- SQLite schema for storing Nostr events with JSON tags support
\
-- Configuration system using config table
\

\
-- Schema version tracking
\
PRAGMA user_version = 7;
\

\
-- Enable foreign key support
\
PRAGMA foreign_keys = ON;
\

\
-- Optimize for performance
\
PRAGMA journal_mode = WAL;
\
PRAGMA synchronous = NORMAL;
\
PRAGMA cache_size = 10000;
\

\
-- Core events table with hybrid single-table design
\
CREATE TABLE events (
\
    id TEXT PRIMARY KEY,                -- Nostr event ID (hex string)
\
    pubkey TEXT NOT NULL,               -- Public key of event author (hex string)
\
    created_at INTEGER NOT NULL,       -- Event creation timestamp (Unix timestamp)
\
    kind INTEGER NOT NULL,              -- Event kind (0-65535)
\
    event_type TEXT NOT NULL CHECK (event_type IN ('regular', 'replaceable', 'ephemeral', 'addressable')),
\
    content TEXT NOT NULL,              -- Event content (text content only)
\
    sig TEXT NOT NULL,                  -- Event signature (hex string)
\
    tags JSON NOT NULL DEFAULT '[]',   -- Event tags as JSON array
\
    first_seen INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))  -- When relay received event
\
);
\

\
-- Core performance indexes
\
CREATE INDEX idx_events_pubkey ON events(pubkey);
\
CREATE INDEX idx_events_kind ON events(kind);
\
CREATE INDEX idx_events_created_at ON events(created_at DESC);
\
CREATE INDEX idx_events_event_type ON events(event_type);
\

\
-- Composite indexes for common query patterns
\
CREATE INDEX idx_events_kind_created_at ON events(kind, created_at DESC);
\
CREATE INDEX idx_events_pubkey_created_at ON events(pubkey, created_at DESC);
\
CREATE INDEX idx_events_pubkey_kind ON events(pubkey, kind);
\

\
-- Schema information table
\
CREATE TABLE schema_info (
\
    key TEXT PRIMARY KEY,
\
    value TEXT NOT NULL,
\
    updated_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
\
);
\

\
-- Insert schema metadata
\
INSERT INTO schema_info (key, value) VALUES
\
    ('version', '7'),
\
    ('description', 'Hybrid Nostr relay schema with event-based and table-based configuration'),
\
    ('created_at', strftime('%s', 'now'));
\

\
-- Helper views for common queries
\
CREATE VIEW recent_events AS
\
SELECT id, pubkey, created_at, kind, event_type, content
\
FROM events
\
WHERE event_type != 'ephemeral'
\
ORDER BY created_at DESC
\
LIMIT 1000;
\

\
CREATE VIEW event_stats AS
\
SELECT 
\
    event_type,
\
    COUNT(*) as count,
\
    AVG(length(content)) as avg_content_length,
\
    MIN(created_at) as earliest,
\
    MAX(created_at) as latest
\
FROM events
\
GROUP BY event_type;
\

\
-- Configuration events view (kind 33334)
\
CREATE VIEW configuration_events AS
\
SELECT 
\
    id,
\
    pubkey as admin_pubkey,
\
    created_at,
\
    content,
\
    tags,
\
    sig
\
FROM events
\
WHERE kind = 33334
\
ORDER BY created_at DESC;
\

\
-- Optimization: Trigger for automatic cleanup of ephemeral events older than 1 hour
\
CREATE TRIGGER cleanup_ephemeral_events
\
    AFTER INSERT ON events
\
    WHEN NEW.event_type = 'ephemeral'
\
BEGIN
\
    DELETE FROM events 
\
    WHERE event_type = 'ephemeral' 
\
    AND first_seen < (strftime('%s', 'now') - 3600);
\
END;
\

\
-- Replaceable event handling trigger
\
CREATE TRIGGER handle_replaceable_events
\
    AFTER INSERT ON events
\
    WHEN NEW.event_type = 'replaceable'
\
BEGIN
\
    DELETE FROM events 
\
    WHERE pubkey = NEW.pubkey 
\
    AND kind = NEW.kind 
\
    AND event_type = 'replaceable'
\
    AND id != NEW.id;
\
END;
\

\
-- Addressable event handling trigger (for kind 33334 configuration events)
\
CREATE TRIGGER handle_addressable_events
\
    AFTER INSERT ON events
\
    WHEN NEW.event_type = 'addressable'
\
BEGIN
\
    -- For kind 33334 (configuration), replace previous config from same admin
\
    DELETE FROM events 
\
    WHERE pubkey = NEW.pubkey 
\
    AND kind = NEW.kind 
\
    AND event_type = 'addressable'
\
    AND id != NEW.id;
\
END;
\

\
-- Relay Private Key Secure Storage
\
-- Stores the relay's private key separately from public configuration
\
CREATE TABLE relay_seckey (
\
    private_key_hex TEXT NOT NULL CHECK (length(private_key_hex) = 64),
\
    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
\
);
\

\
-- Authentication Rules Table for NIP-42 and Policy Enforcement
\
-- Used by request_validator.c for unified validation
\
CREATE TABLE auth_rules (
\
    id INTEGER PRIMARY KEY AUTOINCREMENT,
\
    rule_type TEXT NOT NULL CHECK (rule_type IN ('whitelist', 'blacklist', 'rate_limit', 'auth_required')),
\
    pattern_type TEXT NOT NULL CHECK (pattern_type IN ('pubkey', 'kind', 'ip', 'global')),
\
    pattern_value TEXT,
\
    action TEXT NOT NULL CHECK (action IN ('allow', 'deny', 'require_auth', 'rate_limit')),
\
    parameters TEXT, -- JSON parameters for rate limiting, etc.
\
    active INTEGER NOT NULL DEFAULT 1,
\
    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
\
    updated_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
\
);
\

\
-- Indexes for auth_rules performance
\
CREATE INDEX idx_auth_rules_pattern ON auth_rules(pattern_type, pattern_value);
\
CREATE INDEX idx_auth_rules_type ON auth_rules(rule_type);
\
CREATE INDEX idx_auth_rules_active ON auth_rules(active);
\

\
-- Configuration Table for Table-Based Config Management
\
-- Hybrid system supporting both event-based and table-based configuration
\
CREATE TABLE config (
\
    key TEXT PRIMARY KEY,
\
    value TEXT NOT NULL,
\
    data_type TEXT NOT NULL CHECK (data_type IN ('string', 'integer', 'boolean', 'json')),
\
    description TEXT,
\
    category TEXT DEFAULT 'general',
\
    requires_restart INTEGER DEFAULT 0,
\
    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
\
    updated_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
\
);
\

\
-- Indexes for config table performance
\
CREATE INDEX idx_config_category ON config(category);
\
CREATE INDEX idx_config_restart ON config(requires_restart);
\
CREATE INDEX idx_config_updated ON config(updated_at DESC);
\

\
-- Trigger to update config timestamp on changes
\
CREATE TRIGGER update_config_timestamp
\
    AFTER UPDATE ON config
\
    FOR EACH ROW
\
BEGIN
\
    UPDATE config SET updated_at = strftime('%s', 'now') WHERE key = NEW.key;
\
END;
\

\
-- Insert default configuration values
\
INSERT INTO config (key, value, data_type, description, category, requires_restart) VALUES
\
    ('relay_description', 'A C Nostr Relay', 'string', 'Relay description', 'general', 0),
\
    ('relay_contact', '', 'string', 'Relay contact information', 'general', 0),
\
    ('relay_software', 'https://github.com/laanwj/c-relay', 'string', 'Relay software URL', 'general', 0),
\
    ('relay_version', '1.0.0', 'string', 'Relay version', 'general', 0),
\
    ('relay_port', '8888', 'integer', 'Relay port number', 'network', 1),
\
    ('max_connections', '1000', 'integer', 'Maximum concurrent connections', 'network', 1),
\
    ('auth_enabled', 'false', 'boolean', 'Enable NIP-42 authentication', 'auth', 0),
\
    ('nip42_auth_required_events', 'false', 'boolean', 'Require auth for event publishing', 'auth', 0),
\
    ('nip42_auth_required_subscriptions', 'false', 'boolean', 'Require auth for subscriptions', 'auth', 0),
\
    ('nip42_auth_required_kinds', '[]', 'json', 'Event kinds requiring authentication', 'auth', 0),
\
    ('nip42_challenge_expiration', '600', 'integer', 'Auth challenge expiration seconds', 'auth', 0),
\
    ('pow_min_difficulty', '0', 'integer', 'Minimum proof-of-work difficulty', 'validation', 0),
\
    ('pow_mode', 'optional', 'string', 'Proof-of-work mode', 'validation', 0),
\
    ('nip40_expiration_enabled', 'true', 'boolean', 'Enable event expiration', 'validation', 0),
\
    ('nip40_expiration_strict', 'false', 'boolean', 'Strict expiration mode', 'validation', 0),
\
    ('nip40_expiration_filter', 'true', 'boolean', 'Filter expired events in queries', 'validation', 0),
\
    ('nip40_expiration_grace_period', '60', 'integer', 'Expiration grace period seconds', 'validation', 0),
\
    ('max_subscriptions_per_client', '25', 'integer', 'Maximum subscriptions per client', 'limits', 0),
\
    ('max_total_subscriptions', '1000', 'integer', 'Maximum total subscriptions', 'limits', 0),
\
    ('max_filters_per_subscription', '10', 'integer', 'Maximum filters per subscription', 'limits', 0),
\
    ('max_event_tags', '2000', 'integer', 'Maximum tags per event', 'limits', 0),
\
    ('max_content_length', '100000', 'integer', 'Maximum event content length', 'limits', 0),
\
    ('max_message_length', '131072', 'integer', 'Maximum WebSocket message length', 'limits', 0),
\
    ('default_limit', '100', 'integer', 'Default query limit', 'limits', 0),
\
    ('max_limit', '5000', 'integer', 'Maximum query limit', 'limits', 0);
\

\
-- Persistent Subscriptions Logging Tables (Phase 2)
\
-- Optional database logging for subscription analytics and debugging
\

\
-- Subscription events log
\
CREATE TABLE subscription_events (
\
    id INTEGER PRIMARY KEY AUTOINCREMENT,
\
    subscription_id TEXT NOT NULL,           -- Subscription ID from client
\
    client_ip TEXT NOT NULL,                 -- Client IP address
\
    event_type TEXT NOT NULL CHECK (event_type IN ('created', 'closed', 'expired', 'disconnected')),
\
    filter_json TEXT,                        -- JSON representation of filters (for created events)
\
    events_sent INTEGER DEFAULT 0,           -- Number of events sent to this subscription
\
    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
\
    ended_at INTEGER,                        -- When subscription ended (for closed/expired/disconnected)
\
    duration INTEGER                         -- Computed: ended_at - created_at
\
);
\

\
-- Subscription metrics summary
\
CREATE TABLE subscription_metrics (
\
    id INTEGER PRIMARY KEY AUTOINCREMENT,
\
    date TEXT NOT NULL,                      -- Date (YYYY-MM-DD)
\
    total_created INTEGER DEFAULT 0,         -- Total subscriptions created
\
    total_closed INTEGER DEFAULT 0,          -- Total subscriptions closed
\
    total_events_broadcast INTEGER DEFAULT 0, -- Total events broadcast
\
    avg_duration REAL DEFAULT 0,            -- Average subscription duration
\
    peak_concurrent INTEGER DEFAULT 0,       -- Peak concurrent subscriptions
\
    updated_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
\
    UNIQUE(date)
\
);
\

\
-- Event broadcasting log (optional, for detailed analytics)
\
CREATE TABLE event_broadcasts (
\
    id INTEGER PRIMARY KEY AUTOINCREMENT,
\
    event_id TEXT NOT NULL,                  -- Event ID that was broadcast
\
    subscription_id TEXT NOT NULL,           -- Subscription that received it
\
    client_ip TEXT NOT NULL,                 -- Client IP
\
    broadcast_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
\
    FOREIGN KEY (event_id) REFERENCES events(id)
\
);
\

\
-- Indexes for subscription logging performance
\
CREATE INDEX idx_subscription_events_id ON subscription_events(subscription_id);
\
CREATE INDEX idx_subscription_events_type ON subscription_events(event_type);
\
CREATE INDEX idx_subscription_events_created ON subscription_events(created_at DESC);
\
CREATE INDEX idx_subscription_events_client ON subscription_events(client_ip);
\

\
CREATE INDEX idx_subscription_metrics_date ON subscription_metrics(date DESC);
\

\
CREATE INDEX idx_event_broadcasts_event ON event_broadcasts(event_id);
\
CREATE INDEX idx_event_broadcasts_sub ON event_broadcasts(subscription_id);
\
CREATE INDEX idx_event_broadcasts_time ON event_broadcasts(broadcast_at DESC);
\

\
-- Trigger to update subscription duration when ended
\
CREATE TRIGGER update_subscription_duration
\
    AFTER UPDATE OF ended_at ON subscription_events
\
    WHEN NEW.ended_at IS NOT NULL AND OLD.ended_at IS NULL
\
BEGIN
\
    UPDATE subscription_events
\
    SET duration = NEW.ended_at - NEW.created_at
\
    WHERE id = NEW.id;
\
END;
\

\
-- View for subscription analytics
\
CREATE VIEW subscription_analytics AS
\
SELECT
\
    date(created_at, 'unixepoch') as date,
\
    COUNT(*) as subscriptions_created,
\
    COUNT(CASE WHEN ended_at IS NOT NULL THEN 1 END) as subscriptions_ended,
\
    AVG(CASE WHEN duration IS NOT NULL THEN duration END) as avg_duration_seconds,
\
    MAX(events_sent) as max_events_sent,
\
    AVG(events_sent) as avg_events_sent,
\
    COUNT(DISTINCT client_ip) as unique_clients
\
FROM subscription_events
\
GROUP BY date(created_at, 'unixepoch')
\
ORDER BY date DESC;
\

\
-- View for current active subscriptions (from log perspective)
\
CREATE VIEW active_subscriptions_log AS
\
SELECT
\
    subscription_id,
\
    client_ip,
\
    filter_json,
\
    events_sent,
\
    created_at,
\
    (strftime('%s', 'now') - created_at) as duration_seconds
\
FROM subscription_events
\
WHERE event_type = 'created'
\
AND subscription_id NOT IN (
\
    SELECT subscription_id FROM subscription_events
\
    WHERE event_type IN ('closed', 'expired', 'disconnected')
\
);
\

\
-- Database Statistics Views for Admin API
\
-- Event kinds distribution view
\
CREATE VIEW event_kinds_view AS
\
SELECT
\
    kind,
\
    COUNT(*) as count,
\
    ROUND(COUNT(*) * 100.0 / (SELECT COUNT(*) FROM events), 2) as percentage
\
FROM events
\
GROUP BY kind
\
ORDER BY count DESC;
\

\
-- Top pubkeys by event count view
\
CREATE VIEW top_pubkeys_view AS
\
SELECT
\
    pubkey,
\
    COUNT(*) as event_count,
\
    ROUND(COUNT(*) * 100.0 / (SELECT COUNT(*) FROM events), 2) as percentage
\
FROM events
\
GROUP BY pubkey
\
ORDER BY event_count DESC
\
LIMIT 10;
\

\
-- Time-based statistics view
\
CREATE VIEW time_stats_view AS
\
SELECT
\
    'total' as period,
\
    COUNT(*) as total_events,
\
    COUNT(DISTINCT pubkey) as unique_pubkeys,
\
    MIN(created_at) as oldest_event,
\
    MAX(created_at) as newest_event
\
FROM events
\
UNION ALL
\
SELECT
\
    '24h' as period,
\
    COUNT(*) as total_events,
\
    COUNT(DISTINCT pubkey) as unique_pubkeys,
\
    MIN(created_at) as oldest_event,
\
    MAX(created_at) as newest_event
\
FROM events
\
WHERE created_at >= (strftime('%s', 'now') - 86400)
\
UNION ALL
\
SELECT
\
    '7d' as period,
\
    COUNT(*) as total_events,
\
    COUNT(DISTINCT pubkey) as unique_pubkeys,
\
    MIN(created_at) as oldest_event,
\
    MAX(created_at) as newest_event
\
FROM events
\
WHERE created_at >= (strftime('%s', 'now') - 604800)
\
UNION ALL
\
SELECT
\
    '30d' as period,
\
    COUNT(*) as total_events,
\
    COUNT(DISTINCT pubkey) as unique_pubkeys,
\
    MIN(created_at) as oldest_event,
\
    MAX(created_at) as newest_event
\
FROM events
\
WHERE created_at >= (strftime('%s', 'now') - 2592000);

#endif /* SQL_SCHEMA_H */
