sojorn/go-backend/internal/database/migrations/20260205000002_user_appeal_system.up.sql

-- User Appeal System Migration
-- Creates tables for tracking user violations, appeals, and ban management

-- User Violations Table
CREATE TABLE IF NOT EXISTS user_violations (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    moderation_flag_id UUID NOT NULL REFERENCES moderation_flags(id) ON DELETE CASCADE,
    violation_type VARCHAR(20) NOT NULL CHECK (violation_type IN ('hard_violation', 'soft_violation')),
    violation_reason TEXT NOT NULL,
    severity_score DECIMAL(3,2) NOT NULL CHECK (severity_score >= 0.0 AND severity_score <= 1.0),
    is_appealable BOOLEAN NOT NULL DEFAULT false,
    appeal_deadline TIMESTAMP WITH TIME ZONE,
    status VARCHAR(20) NOT NULL DEFAULT 'active' CHECK (status IN ('active', 'appealed', 'upheld', 'overturned', 'expired')),
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
);

-- User Appeals Table
CREATE TABLE IF NOT EXISTS user_appeals (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    user_violation_id UUID NOT NULL REFERENCES user_violations(id) ON DELETE CASCADE,
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    appeal_reason TEXT NOT NULL,
    appeal_context TEXT,
    evidence_urls JSONB DEFAULT '[]',
    status VARCHAR(20) NOT NULL DEFAULT 'pending' CHECK (status IN ('pending', 'reviewing', 'approved', 'rejected', 'withdrawn')),
    reviewed_by UUID REFERENCES directus_users(id),
    review_decision TEXT,
    reviewed_at TIMESTAMP WITH TIME ZONE,
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
);

-- User Violation History (for tracking patterns)
CREATE TABLE IF NOT EXISTS user_violation_history (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    violation_date DATE NOT NULL,
    total_violations INTEGER NOT NULL DEFAULT 0,
    hard_violations INTEGER NOT NULL DEFAULT 0,
    soft_violations INTEGER NOT NULL DEFAULT 0,
    appeals_filed INTEGER NOT NULL DEFAULT 0,
    appeals_upheld INTEGER NOT NULL DEFAULT 0,
    appeals_overturned INTEGER NOT NULL DEFAULT 0,
    current_status VARCHAR(20) NOT NULL DEFAULT 'active' CHECK (current_status IN ('active', 'suspended', 'banned')),
    ban_expiry TIMESTAMP WITH TIME ZONE,
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    UNIQUE(user_id, violation_date)
);

-- Appeal Guidelines (configurable rules)
CREATE TABLE IF NOT EXISTS appeal_guidelines (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    violation_type VARCHAR(20) NOT NULL,
    max_appeals_per_month INTEGER NOT NULL DEFAULT 3,
    appeal_window_hours INTEGER NOT NULL DEFAULT 72,
    auto_ban_threshold INTEGER NOT NULL DEFAULT 5,
    hard_violation_ban_threshold INTEGER NOT NULL DEFAULT 2,
    is_active BOOLEAN NOT NULL DEFAULT true,
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
);

-- Insert default appeal guidelines
INSERT INTO appeal_guidelines (violation_type, max_appeals_per_month, appeal_window_hours, auto_ban_threshold, hard_violation_ban_threshold)
VALUES 
('hard_violation', 0, 0, 5, 2),
('soft_violation', 3, 72, 8, 3)
ON CONFLICT DO NOTHING;

-- Indexes for performance
CREATE INDEX IF NOT EXISTS idx_user_violations_user_id ON user_violations(user_id);
CREATE INDEX IF NOT EXISTS idx_user_violations_status ON user_violations(status);
CREATE INDEX IF NOT EXISTS idx_user_violations_created_at ON user_violations(created_at);
CREATE INDEX IF NOT EXISTS idx_user_appeals_user_id ON user_appeals(user_id);
CREATE INDEX IF NOT EXISTS idx_user_appeals_status ON user_appeals(status);
CREATE INDEX IF NOT EXISTS idx_user_violation_history_user_id ON user_violation_history(user_id);
CREATE INDEX IF NOT EXISTS idx_user_violation_history_date ON user_violation_history(violation_date);

-- Functions to automatically detect violation type and create violations
CREATE OR REPLACE FUNCTION create_user_violation(
    p_user_id UUID,
    p_moderation_flag_id UUID,
    p_flag_reason TEXT,
    p_scores JSONB
) RETURNS UUID AS $$
DECLARE
    v_violation_id UUID;
    v_violation_type TEXT;
    v_severity DECIMAL;
    v_is_appealable BOOLEAN;
    v_appeal_deadline TIMESTAMP WITH TIME ZONE;
BEGIN
    -- Determine violation type based on scores and reason
    CASE 
        WHEN p_flag_reason IN ('hate') AND (p_scores->>'hate')::DECIMAL > 0.8 THEN
            BEGIN
                v_violation_type := 'hard_violation';
                v_severity := (p_scores->>'hate')::DECIMAL;
                v_is_appealable := false;
                v_appeal_deadline := NULL;
            END;
        WHEN p_flag_reason IN ('hate', 'violence', 'sexual') AND (p_scores->>'hate')::DECIMAL > 0.6 THEN
            BEGIN
                v_violation_type := 'hard_violation';
                v_severity := GREATEST((p_scores->>'hate')::DECIMAL, (p_scores->>'greed')::DECIMAL, (p_scores->>'delusion')::DECIMAL);
                v_is_appealable := false;
                v_appeal_deadline := NULL;
            END;
        ELSE
            BEGIN
                v_violation_type := 'soft_violation';
                v_severity := GREATEST((p_scores->>'hate')::DECIMAL, (p_scores->>'greed')::DECIMAL, (p_scores->>'delusion')::DECIMAL);
                v_is_appealable := true;
                v_appeal_deadline := NOW() + (SELECT appeal_window_hours FROM appeal_guidelines WHERE violation_type = 'soft_violation' AND is_active = true LIMIT 1) * INTERVAL '1 hour';
            END;
    END CASE;
    
    -- Create the violation record
    INSERT INTO user_violations (user_id, moderation_flag_id, violation_type, violation_reason, severity_score, is_appealable, appeal_deadline)
    VALUES (p_user_id, p_moderation_flag_id, v_violation_type, p_flag_reason, v_severity, v_is_appealable, v_appeal_deadline)
    RETURNING id INTO v_violation_id;
    
    -- Update violation history
    INSERT INTO user_violation_history (user_id, violation_date, total_violations, hard_violations, soft_violations)
    VALUES (p_user_id, CURRENT_DATE, 1, 
            CASE WHEN v_violation_type = 'hard_violation' THEN 1 ELSE 0 END,
            CASE WHEN v_violation_type = 'soft_violation' THEN 1 ELSE 0 END)
    ON CONFLICT (user_id, violation_date) 
    DO UPDATE SET
        total_violations = user_violation_history.total_violations + 1,
        hard_violations = user_violation_history.hard_violations + CASE WHEN v_violation_type = 'hard_violation' THEN 1 ELSE 0 END,
        soft_violations = user_violation_history.soft_violations + CASE WHEN v_violation_type = 'soft_violation' THEN 1 ELSE 0 END,
        updated_at = NOW();
    
    -- Check for auto-ban conditions
    PERFORM check_user_ban_status(p_user_id);
    
    RETURN v_violation_id;
END;
$$ LANGUAGE plpgsql;

-- Function to check if user should be banned
CREATE OR REPLACE FUNCTION check_user_ban_status(p_user_id UUID) RETURNS BOOLEAN AS $$
DECLARE
    v_hard_count INTEGER;
    v_total_count INTEGER;
    v_ban_threshold INTEGER;
    v_hard_ban_threshold INTEGER;
BEGIN
    -- Get counts from last 30 days
    SELECT COUNT(*), SUM(CASE WHEN violation_type = 'hard_violation' THEN 1 ELSE 0 END)
    INTO v_total_count, v_hard_count
    FROM user_violations 
    WHERE user_id = p_user_id 
    AND created_at >= NOW() - INTERVAL '30 days';
    
    -- Get thresholds
    SELECT auto_ban_threshold, hard_violation_ban_threshold
    INTO v_ban_threshold, v_hard_ban_threshold
    FROM appeal_guidelines 
    WHERE is_active = true 
    LIMIT 1;
    
    -- Check ban conditions
    IF v_hard_count >= v_hard_ban_threshold OR v_total_count >= v_ban_threshold THEN
        -- Ban the user
        UPDATE users 
        SET status = 'banned', updated_at = NOW()
        WHERE id = p_user_id;
        
        -- Update violation history
        UPDATE user_violation_history 
        SET current_status = 'banned', updated_at = NOW()
        WHERE user_id = p_user_id AND violation_date = CURRENT_DATE;
        
        RETURN true;
    END IF;
    
    RETURN false;
END;
$$ LANGUAGE plpgsql;

-- Add to Directus collections
INSERT INTO directus_collections (collection, icon, note, hidden, singleton) VALUES 
('user_violations', 'warning', 'User violations and moderation records', false, false),
('user_appeals', 'gavel', 'User appeals for moderation decisions', false, false),
('user_violation_history', 'history', 'Daily violation history for users', false, false),
('appeal_guidelines', 'settings', 'Configurable appeal system guidelines', false, false)
ON CONFLICT (collection) DO NOTHING;