likwid/backend/migrations/20260126270000_self_moderation_rules.sql

-- ============================================================================
-- SELF-MODERATION RULES PLUGIN
-- Configurable community rules with automatic escalation and voting on sanctions
-- ============================================================================

-- ============================================================================
-- COMMUNITY RULES
-- Configurable rules that communities can define
-- ============================================================================

CREATE TYPE rule_severity AS ENUM ('info', 'warning', 'minor', 'major', 'critical');
CREATE TYPE rule_scope AS ENUM ('content', 'behavior', 'voting', 'participation', 'meta');

CREATE TABLE community_rules (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    community_id UUID NOT NULL REFERENCES communities(id) ON DELETE CASCADE,
    
    -- Rule definition
    code VARCHAR(50) NOT NULL,
    title VARCHAR(200) NOT NULL,
    description TEXT NOT NULL,
    scope rule_scope NOT NULL DEFAULT 'behavior',
    severity rule_severity NOT NULL DEFAULT 'warning',
    
    -- Rule behavior
    is_active BOOLEAN NOT NULL DEFAULT TRUE,
    requires_human_review BOOLEAN NOT NULL DEFAULT TRUE,
    auto_detection_enabled BOOLEAN NOT NULL DEFAULT FALSE,
    detection_patterns JSONB, -- For automated detection
    
    -- Sanctions
    default_sanction_type VARCHAR(50),
    default_sanction_duration_hours INT,
    escalation_multiplier DECIMAL(3,2) NOT NULL DEFAULT 1.5,
    max_escalation_level INT NOT NULL DEFAULT 3,
    
    -- Voting on sanctions
    allow_community_vote BOOLEAN NOT NULL DEFAULT FALSE,
    vote_threshold DECIMAL(5,4) NOT NULL DEFAULT 0.6667, -- 2/3 majority
    vote_quorum DECIMAL(5,4) NOT NULL DEFAULT 0.10,
    vote_duration_hours INT NOT NULL DEFAULT 48,
    
    -- Metadata
    created_by UUID REFERENCES users(id),
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    version INT NOT NULL DEFAULT 1,
    
    UNIQUE(community_id, code)
);

CREATE INDEX idx_community_rules_community ON community_rules(community_id);
CREATE INDEX idx_community_rules_active ON community_rules(community_id, is_active) WHERE is_active = true;
CREATE INDEX idx_community_rules_scope ON community_rules(community_id, scope);

COMMENT ON TABLE community_rules IS 'Community-defined moderation rules';

-- ============================================================================
-- RULE VIOLATIONS
-- Reported or detected rule violations
-- ============================================================================

CREATE TYPE violation_status AS ENUM (
    'reported',      -- Initial report
    'under_review',  -- Being reviewed by moderator
    'pending_vote',  -- Community vote in progress
    'confirmed',     -- Violation confirmed
    'dismissed',     -- Report dismissed
    'appealed',      -- Under appeal
    'resolved'       -- Sanction applied and completed
);

CREATE TABLE rule_violations (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    community_id UUID NOT NULL REFERENCES communities(id) ON DELETE CASCADE,
    rule_id UUID NOT NULL REFERENCES community_rules(id),
    
    -- Violation details
    target_user_id UUID NOT NULL REFERENCES users(id),
    target_content_id UUID,
    target_content_type VARCHAR(50),
    
    -- Reporter
    reported_by UUID REFERENCES users(id),
    reported_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    report_reason TEXT,
    report_evidence JSONB,
    
    -- Status tracking
    status violation_status NOT NULL DEFAULT 'reported',
    escalation_level INT NOT NULL DEFAULT 0,
    
    -- Review
    reviewed_by UUID REFERENCES users(id),
    reviewed_at TIMESTAMPTZ,
    review_notes TEXT,
    
    -- Community vote (if applicable)
    vote_proposal_id UUID REFERENCES proposals(id),
    vote_started_at TIMESTAMPTZ,
    vote_ended_at TIMESTAMPTZ,
    vote_result JSONB,
    
    -- Resolution
    resolved_at TIMESTAMPTZ,
    resolution_type VARCHAR(50), -- sanction_applied, dismissed, appealed_overturned
    resolution_notes TEXT,
    
    -- Audit
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE INDEX idx_rule_violations_community ON rule_violations(community_id);
CREATE INDEX idx_rule_violations_target ON rule_violations(target_user_id);
CREATE INDEX idx_rule_violations_status ON rule_violations(status);
CREATE INDEX idx_rule_violations_rule ON rule_violations(rule_id);
CREATE INDEX idx_rule_violations_pending ON rule_violations(community_id, status) 
    WHERE status IN ('reported', 'under_review', 'pending_vote');

COMMENT ON TABLE rule_violations IS 'Tracked rule violations and their resolution';

-- ============================================================================
-- SANCTIONS
-- Applied sanctions for violations
-- ============================================================================

CREATE TYPE sanction_type AS ENUM (
    'warning',           -- Official warning
    'content_removal',   -- Remove offending content
    'temporary_mute',    -- Cannot post/comment temporarily
    'temporary_suspend', -- Cannot access community temporarily
    'voting_suspension', -- Cannot vote temporarily
    'permanent_ban',     -- Permanent community ban
    'custom'            -- Custom sanction
);

CREATE TYPE sanction_status AS ENUM (
    'pending',    -- Awaiting application
    'active',     -- Currently in effect
    'completed',  -- Duration expired
    'lifted',     -- Manually lifted early
    'appealed'    -- Overturned on appeal
);

CREATE TABLE sanctions (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    violation_id UUID NOT NULL REFERENCES rule_violations(id),
    community_id UUID NOT NULL REFERENCES communities(id) ON DELETE CASCADE,
    target_user_id UUID NOT NULL REFERENCES users(id),
    
    -- Sanction details
    sanction_type sanction_type NOT NULL,
    severity_level INT NOT NULL DEFAULT 1,
    description TEXT,
    
    -- Duration
    starts_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    duration_hours INT,
    expires_at TIMESTAMPTZ,
    
    -- Status
    status sanction_status NOT NULL DEFAULT 'active',
    
    -- Applied by
    applied_by UUID REFERENCES users(id),
    applied_via VARCHAR(50) NOT NULL DEFAULT 'manual', -- manual, vote, auto
    
    -- Lifting/Appeal
    lifted_at TIMESTAMPTZ,
    lifted_by UUID REFERENCES users(id),
    lift_reason TEXT,
    
    -- Audit
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    ledger_entry_id UUID -- Reference to moderation ledger
);

CREATE INDEX idx_sanctions_violation ON sanctions(violation_id);
CREATE INDEX idx_sanctions_target ON sanctions(target_user_id);
CREATE INDEX idx_sanctions_community ON sanctions(community_id);
CREATE INDEX idx_sanctions_status ON sanctions(status);
CREATE INDEX idx_sanctions_active ON sanctions(target_user_id, status, expires_at) 
    WHERE status = 'active';

COMMENT ON TABLE sanctions IS 'Applied sanctions for rule violations';

-- ============================================================================
-- USER VIOLATION HISTORY
-- Aggregated view of user's violation history
-- ============================================================================

CREATE TABLE user_violation_summary (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    user_id UUID NOT NULL REFERENCES users(id),
    community_id UUID NOT NULL REFERENCES communities(id) ON DELETE CASCADE,
    
    -- Counts
    total_violations INT NOT NULL DEFAULT 0,
    confirmed_violations INT NOT NULL DEFAULT 0,
    dismissed_violations INT NOT NULL DEFAULT 0,
    
    -- Sanctions
    total_sanctions INT NOT NULL DEFAULT 0,
    active_sanctions INT NOT NULL DEFAULT 0,
    warnings_count INT NOT NULL DEFAULT 0,
    mutes_count INT NOT NULL DEFAULT 0,
    suspensions_count INT NOT NULL DEFAULT 0,
    
    -- Escalation tracking
    current_escalation_level INT NOT NULL DEFAULT 0,
    last_violation_at TIMESTAMPTZ,
    last_sanction_at TIMESTAMPTZ,
    
    -- Good standing calculation
    days_since_last_violation INT,
    is_in_good_standing BOOLEAN NOT NULL DEFAULT TRUE,
    
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE(user_id, community_id)
);

CREATE INDEX idx_user_violation_summary_user ON user_violation_summary(user_id);
CREATE INDEX idx_user_violation_summary_community ON user_violation_summary(community_id);

COMMENT ON TABLE user_violation_summary IS 'Aggregated violation history per user per community';

-- ============================================================================
-- ESCALATION RULES
-- Define how sanctions escalate with repeated violations
-- ============================================================================

CREATE TABLE escalation_rules (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    community_id UUID NOT NULL REFERENCES communities(id) ON DELETE CASCADE,
    rule_id UUID REFERENCES community_rules(id) ON DELETE CASCADE,
    
    -- Escalation level
    level INT NOT NULL,
    
    -- Sanction for this level
    sanction_type sanction_type NOT NULL,
    duration_hours INT,
    additional_actions JSONB,
    
    -- Conditions
    cooldown_days INT NOT NULL DEFAULT 90, -- Days before escalation resets
    
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE(community_id, rule_id, level)
);

CREATE INDEX idx_escalation_rules_community ON escalation_rules(community_id);
CREATE INDEX idx_escalation_rules_rule ON escalation_rules(rule_id);

COMMENT ON TABLE escalation_rules IS 'Escalation ladder for repeated violations';

-- ============================================================================
-- HELPER FUNCTIONS
-- ============================================================================

-- Calculate escalation level for a user/rule combination
CREATE OR REPLACE FUNCTION calculate_escalation_level(
    p_user_id UUID,
    p_community_id UUID,
    p_rule_id UUID
) RETURNS INT AS $$
DECLARE
    v_level INT;
    v_cooldown_days INT;
BEGIN
    -- Get the escalation cooldown
    SELECT COALESCE(MAX(cooldown_days), 90) INTO v_cooldown_days
    FROM escalation_rules
    WHERE community_id = p_community_id AND (rule_id = p_rule_id OR rule_id IS NULL);
    
    -- Count confirmed violations within cooldown period
    SELECT COUNT(*) INTO v_level
    FROM rule_violations
    WHERE target_user_id = p_user_id
      AND community_id = p_community_id
      AND rule_id = p_rule_id
      AND status = 'confirmed'
      AND resolved_at > NOW() - (v_cooldown_days || ' days')::INTERVAL;
    
    RETURN v_level;
END;
$$ LANGUAGE plpgsql;

-- Get appropriate sanction for escalation level
CREATE OR REPLACE FUNCTION get_escalated_sanction(
    p_community_id UUID,
    p_rule_id UUID,
    p_level INT
) RETURNS TABLE (
    sanction_type sanction_type,
    duration_hours INT
) AS $$
BEGIN
    -- Try rule-specific escalation
    RETURN QUERY
    SELECT er.sanction_type, er.duration_hours
    FROM escalation_rules er
    WHERE er.community_id = p_community_id
      AND er.rule_id = p_rule_id
      AND er.level = p_level
    LIMIT 1;
    
    IF NOT FOUND THEN
        -- Try community default escalation
        RETURN QUERY
        SELECT er.sanction_type, er.duration_hours
        FROM escalation_rules er
        WHERE er.community_id = p_community_id
          AND er.rule_id IS NULL
          AND er.level = p_level
        LIMIT 1;
    END IF;
    
    IF NOT FOUND THEN
        -- Default escalation ladder
        RETURN QUERY
        SELECT 
            CASE p_level
                WHEN 1 THEN 'warning'::sanction_type
                WHEN 2 THEN 'temporary_mute'::sanction_type
                WHEN 3 THEN 'temporary_suspend'::sanction_type
                ELSE 'permanent_ban'::sanction_type
            END,
            CASE p_level
                WHEN 1 THEN NULL::INT
                WHEN 2 THEN 24
                WHEN 3 THEN 168
                ELSE NULL
            END;
    END IF;
END;
$$ LANGUAGE plpgsql;

-- Apply a sanction
CREATE OR REPLACE FUNCTION apply_sanction(
    p_violation_id UUID,
    p_sanction_type sanction_type,
    p_duration_hours INT,
    p_applied_by UUID,
    p_applied_via VARCHAR(50)
) RETURNS UUID AS $$
DECLARE
    v_violation rule_violations%ROWTYPE;
    v_sanction_id UUID;
    v_expires_at TIMESTAMPTZ;
BEGIN
    -- Get violation details
    SELECT * INTO v_violation FROM rule_violations WHERE id = p_violation_id;
    
    -- Calculate expiration
    IF p_duration_hours IS NOT NULL THEN
        v_expires_at := NOW() + (p_duration_hours || ' hours')::INTERVAL;
    END IF;
    
    -- Create sanction
    INSERT INTO sanctions (
        violation_id, community_id, target_user_id,
        sanction_type, duration_hours, expires_at,
        applied_by, applied_via
    ) VALUES (
        p_violation_id, v_violation.community_id, v_violation.target_user_id,
        p_sanction_type, p_duration_hours, v_expires_at,
        p_applied_by, p_applied_via
    ) RETURNING id INTO v_sanction_id;
    
    -- Update violation status
    UPDATE rule_violations
    SET status = 'resolved',
        resolved_at = NOW(),
        resolution_type = 'sanction_applied'
    WHERE id = p_violation_id;
    
    -- Update user summary
    INSERT INTO user_violation_summary (user_id, community_id, confirmed_violations, total_sanctions, last_sanction_at)
    VALUES (v_violation.target_user_id, v_violation.community_id, 1, 1, NOW())
    ON CONFLICT (user_id, community_id) DO UPDATE SET
        confirmed_violations = user_violation_summary.confirmed_violations + 1,
        total_sanctions = user_violation_summary.total_sanctions + 1,
        last_sanction_at = NOW(),
        updated_at = NOW();
    
    RETURN v_sanction_id;
END;
$$ LANGUAGE plpgsql;

-- Check and expire sanctions
CREATE OR REPLACE FUNCTION expire_sanctions() RETURNS INT AS $$
DECLARE
    v_count INT;
BEGIN
    UPDATE sanctions
    SET status = 'completed'
    WHERE status = 'active'
      AND expires_at IS NOT NULL
      AND expires_at < NOW();
    
    GET DIAGNOSTICS v_count = ROW_COUNT;
    RETURN v_count;
END;
$$ LANGUAGE plpgsql;

-- Check if user has active sanction
CREATE OR REPLACE FUNCTION user_has_active_sanction(
    p_user_id UUID,
    p_community_id UUID,
    p_sanction_type sanction_type DEFAULT NULL
) RETURNS BOOLEAN AS $$
BEGIN
    RETURN EXISTS (
        SELECT 1 FROM sanctions
        WHERE target_user_id = p_user_id
          AND community_id = p_community_id
          AND status = 'active'
          AND (p_sanction_type IS NULL OR sanction_type = p_sanction_type)
          AND (expires_at IS NULL OR expires_at > NOW())
    );
END;
$$ LANGUAGE plpgsql;

-- ============================================================================
-- DEFAULT ESCALATION RULES
-- ============================================================================

-- These will be created per-community when needed

-- ============================================================================
-- VIEWS
-- ============================================================================

CREATE OR REPLACE VIEW pending_violations AS
SELECT 
    rv.id,
    rv.community_id,
    c.name AS community_name,
    cr.code AS rule_code,
    cr.title AS rule_title,
    cr.severity,
    rv.target_user_id,
    tu.username AS target_username,
    rv.reported_by,
    ru.username AS reporter_username,
    rv.status,
    rv.reported_at,
    rv.report_reason
FROM rule_violations rv
JOIN communities c ON c.id = rv.community_id
JOIN community_rules cr ON cr.id = rv.rule_id
JOIN users tu ON tu.id = rv.target_user_id
LEFT JOIN users ru ON ru.id = rv.reported_by
WHERE rv.status IN ('reported', 'under_review', 'pending_vote')
ORDER BY 
    CASE cr.severity 
        WHEN 'critical' THEN 1 
        WHEN 'major' THEN 2 
        WHEN 'minor' THEN 3 
        WHEN 'warning' THEN 4 
        ELSE 5 
    END,
    rv.reported_at;

CREATE OR REPLACE VIEW active_sanctions_view AS
SELECT 
    s.id,
    s.community_id,
    c.name AS community_name,
    s.target_user_id,
    u.username AS target_username,
    s.sanction_type::text,
    s.severity_level,
    s.starts_at,
    s.expires_at,
    s.status::text,
    CASE 
        WHEN s.expires_at IS NULL THEN NULL
        ELSE EXTRACT(EPOCH FROM (s.expires_at - NOW())) / 3600
    END AS hours_remaining
FROM sanctions s
JOIN communities c ON c.id = s.community_id
JOIN users u ON u.id = s.target_user_id
WHERE s.status = 'active'
ORDER BY s.starts_at DESC;

-- ============================================================================
-- PLUGIN REGISTRATION
-- ============================================================================

INSERT INTO plugins (name, description, version, is_core, is_active, settings_schema)
VALUES (
    'self_moderation_rules',
    'Community-configurable moderation rules with automatic escalation, voting on sanctions, and transparent governance of governance.',
    '1.0.0',
    false,
    true,
    jsonb_build_object(
        'type', 'object',
        'properties', jsonb_build_object(
            'default_vote_duration_hours', jsonb_build_object(
                'type', 'integer',
                'title', 'Default Vote Duration',
                'description', 'Default hours for community votes on sanctions',
                'default', 48,
                'minimum', 12,
                'maximum', 168
            ),
            'auto_expire_sanctions', jsonb_build_object(
                'type', 'boolean',
                'title', 'Auto-expire Sanctions',
                'description', 'Automatically expire sanctions when duration ends',
                'default', true
            ),
            'escalation_cooldown_days', jsonb_build_object(
                'type', 'integer',
                'title', 'Escalation Cooldown',
                'description', 'Days of good behavior before escalation level resets',
                'default', 90,
                'minimum', 30,
                'maximum', 365
            ),
            'require_evidence', jsonb_build_object(
                'type', 'boolean',
                'title', 'Require Evidence',
                'description', 'Require evidence attachment when reporting violations',
                'default', false
            ),
            'allow_anonymous_reports', jsonb_build_object(
                'type', 'boolean',
                'title', 'Allow Anonymous Reports',
                'description', 'Allow members to report violations anonymously',
                'default', false
            )
        )
    )
) ON CONFLICT (name) DO UPDATE SET
    version = EXCLUDED.version,
    description = EXCLUDED.description;