-- ============================================================================
-- GOVERNANCE ANALYTICS PLUGIN
-- Participation metrics, delegation distribution, decision load analytics
-- No individual ranking - focuses on aggregate health metrics
-- ============================================================================

-- ============================================================================
-- PARTICIPATION SNAPSHOTS
-- Periodic snapshots of participation metrics
-- ============================================================================

CREATE TABLE participation_snapshots (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    community_id UUID NOT NULL REFERENCES communities(id) ON DELETE CASCADE,
    snapshot_date DATE NOT NULL,
    snapshot_type VARCHAR(50) NOT NULL DEFAULT 'daily', -- daily, weekly, monthly
    
    -- Member counts
    total_members INT NOT NULL DEFAULT 0,
    active_members INT NOT NULL DEFAULT 0, -- Active in period
    new_members INT NOT NULL DEFAULT 0,
    churned_members INT NOT NULL DEFAULT 0,
    
    -- Proposal metrics
    proposals_created INT NOT NULL DEFAULT 0,
    proposals_passed INT NOT NULL DEFAULT 0,
    proposals_rejected INT NOT NULL DEFAULT 0,
    proposals_active INT NOT NULL DEFAULT 0,
    
    -- Voting metrics
    votes_cast INT NOT NULL DEFAULT 0,
    unique_voters INT NOT NULL DEFAULT 0,
    avg_votes_per_proposal DECIMAL(10,2),
    voter_turnout_rate DECIMAL(5,4), -- percentage
    
    -- Discussion metrics
    comments_created INT NOT NULL DEFAULT 0,
    unique_commenters INT NOT NULL DEFAULT 0,
    avg_comments_per_proposal DECIMAL(10,2),
    
    -- Delegation metrics
    active_delegations INT NOT NULL DEFAULT 0,
    delegation_depth_avg DECIMAL(5,2),
    delegation_concentration DECIMAL(5,4), -- Gini-like measure
    
    -- Engagement score (aggregate, not individual)
    engagement_score DECIMAL(5,2),
    
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE(community_id, snapshot_date, snapshot_type)
);

CREATE INDEX idx_participation_snapshots_community ON participation_snapshots(community_id);
CREATE INDEX idx_participation_snapshots_date ON participation_snapshots(snapshot_date);
CREATE INDEX idx_participation_snapshots_lookup ON participation_snapshots(community_id, snapshot_date DESC);

COMMENT ON TABLE participation_snapshots IS 'Periodic participation metrics snapshots';

-- ============================================================================
-- DELEGATION ANALYTICS
-- Aggregate delegation network analysis (no individual tracking)
-- ============================================================================

CREATE TABLE delegation_analytics (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    community_id UUID NOT NULL REFERENCES communities(id) ON DELETE CASCADE,
    topic_id UUID, -- Optional topic filtering
    snapshot_date DATE NOT NULL,
    
    -- Network metrics
    total_delegations INT NOT NULL DEFAULT 0,
    unique_delegators INT NOT NULL DEFAULT 0,
    unique_delegates INT NOT NULL DEFAULT 0,
    
    -- Chain analysis
    max_chain_depth INT NOT NULL DEFAULT 0,
    avg_chain_depth DECIMAL(5,2),
    delegation_cycles_detected INT NOT NULL DEFAULT 0,
    
    -- Concentration metrics (no individual data)
    top_10_delegate_share DECIMAL(5,4), -- Share of votes held by top 10 delegates
    herfindahl_index DECIMAL(7,6), -- Market concentration measure
    effective_delegates INT, -- Number of delegates holding 50% of delegated power
    
    -- Activity
    delegations_created INT NOT NULL DEFAULT 0,
    delegations_revoked INT NOT NULL DEFAULT 0,
    
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE(community_id, topic_id, snapshot_date)
);

CREATE INDEX idx_delegation_analytics_community ON delegation_analytics(community_id);
CREATE INDEX idx_delegation_analytics_topic ON delegation_analytics(topic_id);

COMMENT ON TABLE delegation_analytics IS 'Aggregate delegation network metrics';

-- ============================================================================
-- DECISION LOAD METRICS
-- Track governance workload and throughput
-- ============================================================================

CREATE TABLE decision_load_metrics (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    community_id UUID NOT NULL REFERENCES communities(id) ON DELETE CASCADE,
    period_start DATE NOT NULL,
    period_end DATE NOT NULL,
    
    -- Workload
    proposals_in_pipeline INT NOT NULL DEFAULT 0,
    proposals_needing_review INT NOT NULL DEFAULT 0,
    proposals_in_voting INT NOT NULL DEFAULT 0,
    
    -- Throughput
    decisions_made INT NOT NULL DEFAULT 0,
    avg_decision_time_hours DECIMAL(10,2),
    median_decision_time_hours DECIMAL(10,2),
    
    -- Quality indicators
    proposals_requiring_revision INT NOT NULL DEFAULT 0,
    revision_rate DECIMAL(5,4),
    quorum_achievement_rate DECIMAL(5,4),
    
    -- Bottlenecks
    stalled_proposals INT NOT NULL DEFAULT 0,
    bottleneck_phase VARCHAR(50),
    
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE(community_id, period_start, period_end)
);

CREATE INDEX idx_decision_load_community ON decision_load_metrics(community_id);

COMMENT ON TABLE decision_load_metrics IS 'Governance workload and throughput metrics';

-- ============================================================================
-- VOTING METHOD ANALYTICS
-- Compare effectiveness of different voting methods
-- ============================================================================

CREATE TABLE voting_method_analytics (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    community_id UUID NOT NULL REFERENCES communities(id) ON DELETE CASCADE,
    voting_method VARCHAR(50) NOT NULL,
    period_start DATE NOT NULL,
    period_end DATE NOT NULL,
    
    -- Usage
    proposals_using_method INT NOT NULL DEFAULT 0,
    total_votes_cast INT NOT NULL DEFAULT 0,
    
    -- Participation
    avg_turnout DECIMAL(5,4),
    avg_time_to_decide_hours DECIMAL(10,2),
    
    -- Outcomes
    decisive_results INT NOT NULL DEFAULT 0, -- Clear winner
    close_results INT NOT NULL DEFAULT 0, -- Narrow margins
    tie_results INT NOT NULL DEFAULT 0,
    
    -- Satisfaction proxy (based on post-vote engagement)
    post_decision_engagement_rate DECIMAL(5,4),
    appeal_rate DECIMAL(5,4),
    
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE(community_id, voting_method, period_start, period_end)
);

CREATE INDEX idx_voting_method_analytics_community ON voting_method_analytics(community_id);

COMMENT ON TABLE voting_method_analytics IS 'Voting method effectiveness comparison';

-- ============================================================================
-- HEALTH INDICATORS
-- Overall governance health dashboard data
-- ============================================================================

CREATE TABLE governance_health_indicators (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    community_id UUID NOT NULL REFERENCES communities(id) ON DELETE CASCADE,
    calculated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    
    -- Participation health (0-100)
    participation_score DECIMAL(5,2),
    participation_trend VARCHAR(20), -- improving, stable, declining
    
    -- Inclusion health
    inclusion_score DECIMAL(5,2),
    new_voice_ratio DECIMAL(5,4), -- New participants in decisions
    
    -- Efficiency health
    efficiency_score DECIMAL(5,2),
    decision_velocity DECIMAL(10,2), -- Decisions per week
    
    -- Legitimacy health
    legitimacy_score DECIMAL(5,2),
    avg_quorum_margin DECIMAL(5,4), -- How much above quorum
    
    -- Delegation health
    delegation_health_score DECIMAL(5,2),
    power_concentration_risk VARCHAR(20), -- low, medium, high
    
    -- Overall
    overall_health_score DECIMAL(5,2),
    recommendations JSONB,
    
    UNIQUE(community_id, calculated_at)
);

CREATE INDEX idx_health_indicators_community ON governance_health_indicators(community_id);
CREATE INDEX idx_health_indicators_time ON governance_health_indicators(community_id, calculated_at DESC);

COMMENT ON TABLE governance_health_indicators IS 'Composite governance health metrics';

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

-- Calculate participation snapshot for a community
CREATE OR REPLACE FUNCTION calculate_participation_snapshot(
    p_community_id UUID,
    p_date DATE DEFAULT CURRENT_DATE
) RETURNS UUID AS $$
DECLARE
    v_snapshot_id UUID;
    v_total_members INT;
    v_active_members INT;
    v_proposals_created INT;
    v_votes_cast INT;
    v_unique_voters INT;
    v_active_delegations INT;
BEGIN
    -- Get member counts
    SELECT COUNT(*) INTO v_total_members
    FROM community_members WHERE community_id = p_community_id;
    
    -- Active members (any activity in last 30 days)
    SELECT COUNT(DISTINCT user_id) INTO v_active_members
    FROM (
        SELECT author_id AS user_id FROM proposals 
        WHERE community_id = p_community_id AND created_at > p_date - INTERVAL '30 days'
        UNION
        SELECT user_id FROM votes v
        JOIN proposals p ON p.id = v.proposal_id
        WHERE p.community_id = p_community_id AND v.created_at > p_date - INTERVAL '30 days'
        UNION
        SELECT author_id FROM comments c
        JOIN proposals p ON p.id = c.proposal_id
        WHERE p.community_id = p_community_id AND c.created_at > p_date - INTERVAL '30 days'
    ) activity;
    
    -- Proposals in period
    SELECT COUNT(*) INTO v_proposals_created
    FROM proposals 
    WHERE community_id = p_community_id 
      AND created_at::DATE = p_date;
    
    -- Votes in period
    SELECT COUNT(*), COUNT(DISTINCT user_id) 
    INTO v_votes_cast, v_unique_voters
    FROM votes v
    JOIN proposals p ON p.id = v.proposal_id
    WHERE p.community_id = p_community_id 
      AND v.created_at::DATE = p_date;
    
    -- Active delegations
    SELECT COUNT(*) INTO v_active_delegations
    FROM delegations
    WHERE community_id = p_community_id
      AND (expires_at IS NULL OR expires_at > NOW());
    
    -- Insert snapshot
    INSERT INTO participation_snapshots (
        community_id, snapshot_date, snapshot_type,
        total_members, active_members,
        proposals_created, votes_cast, unique_voters,
        active_delegations,
        voter_turnout_rate,
        engagement_score
    ) VALUES (
        p_community_id, p_date, 'daily',
        v_total_members, v_active_members,
        v_proposals_created, v_votes_cast, v_unique_voters,
        v_active_delegations,
        CASE WHEN v_total_members > 0 THEN v_unique_voters::DECIMAL / v_total_members ELSE 0 END,
        CASE WHEN v_total_members > 0 THEN v_active_members::DECIMAL / v_total_members * 100 ELSE 0 END
    )
    ON CONFLICT (community_id, snapshot_date, snapshot_type) DO UPDATE SET
        total_members = EXCLUDED.total_members,
        active_members = EXCLUDED.active_members,
        proposals_created = EXCLUDED.proposals_created,
        votes_cast = EXCLUDED.votes_cast,
        unique_voters = EXCLUDED.unique_voters,
        active_delegations = EXCLUDED.active_delegations,
        voter_turnout_rate = EXCLUDED.voter_turnout_rate,
        engagement_score = EXCLUDED.engagement_score
    RETURNING id INTO v_snapshot_id;
    
    RETURN v_snapshot_id;
END;
$$ LANGUAGE plpgsql;

-- Calculate delegation concentration (Herfindahl Index)
CREATE OR REPLACE FUNCTION calculate_delegation_concentration(
    p_community_id UUID
) RETURNS DECIMAL AS $$
DECLARE
    v_hhi DECIMAL;
    v_total_delegated DECIMAL;
BEGIN
    -- Get total delegated voting power
    SELECT COALESCE(SUM(voting_power), 0) INTO v_total_delegated
    FROM delegations
    WHERE community_id = p_community_id
      AND (expires_at IS NULL OR expires_at > NOW());
    
    IF v_total_delegated = 0 THEN
        RETURN 0;
    END IF;
    
    -- Calculate HHI (sum of squared market shares)
    SELECT COALESCE(SUM(POWER(delegate_share, 2)), 0) INTO v_hhi
    FROM (
        SELECT 
            delegate_id,
            SUM(voting_power)::DECIMAL / v_total_delegated AS delegate_share
        FROM delegations
        WHERE community_id = p_community_id
          AND (expires_at IS NULL OR expires_at > NOW())
        GROUP BY delegate_id
    ) shares;
    
    RETURN v_hhi;
END;
$$ LANGUAGE plpgsql;

-- Calculate governance health score
CREATE OR REPLACE FUNCTION calculate_governance_health(
    p_community_id UUID
) RETURNS UUID AS $$
DECLARE
    v_health_id UUID;
    v_participation_score DECIMAL;
    v_efficiency_score DECIMAL;
    v_delegation_score DECIMAL;
    v_overall_score DECIMAL;
    v_hhi DECIMAL;
    v_power_risk VARCHAR(20);
BEGIN
    -- Participation score (based on recent activity)
    SELECT COALESCE(AVG(engagement_score), 50) INTO v_participation_score
    FROM participation_snapshots
    WHERE community_id = p_community_id
      AND snapshot_date > CURRENT_DATE - INTERVAL '30 days';
    
    -- Efficiency score (based on decision throughput)
    SELECT COALESCE(
        100 - (COALESCE(AVG(avg_decision_time_hours), 168) / 168 * 50), -- Penalize slow decisions
        50
    ) INTO v_efficiency_score
    FROM decision_load_metrics
    WHERE community_id = p_community_id
      AND period_end > CURRENT_DATE - INTERVAL '30 days';
    
    -- Delegation health
    v_hhi := calculate_delegation_concentration(p_community_id);
    v_delegation_score := 100 - (v_hhi * 100); -- Lower HHI = better
    
    -- Determine power concentration risk
    v_power_risk := CASE
        WHEN v_hhi > 0.25 THEN 'high'
        WHEN v_hhi > 0.15 THEN 'medium'
        ELSE 'low'
    END;
    
    -- Overall score (weighted average)
    v_overall_score := (v_participation_score * 0.4 + v_efficiency_score * 0.3 + v_delegation_score * 0.3);
    
    -- Insert health record
    INSERT INTO governance_health_indicators (
        community_id,
        participation_score,
        participation_trend,
        efficiency_score,
        delegation_health_score,
        power_concentration_risk,
        overall_health_score,
        recommendations
    ) VALUES (
        p_community_id,
        v_participation_score,
        'stable', -- Would need trend calculation
        v_efficiency_score,
        v_delegation_score,
        v_power_risk,
        v_overall_score,
        jsonb_build_array(
            CASE WHEN v_participation_score < 50 THEN 'Consider outreach to increase participation' END,
            CASE WHEN v_efficiency_score < 50 THEN 'Review workflow to reduce decision time' END,
            CASE WHEN v_power_risk = 'high' THEN 'High delegation concentration - encourage diverse delegation' END
        )
    )
    RETURNING id INTO v_health_id;
    
    RETURN v_health_id;
END;
$$ LANGUAGE plpgsql;

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

CREATE OR REPLACE VIEW community_health_dashboard AS
SELECT 
    c.id AS community_id,
    c.name AS community_name,
    ghi.overall_health_score,
    ghi.participation_score,
    ghi.efficiency_score,
    ghi.delegation_health_score,
    ghi.power_concentration_risk,
    ghi.calculated_at AS last_calculated,
    ps.total_members,
    ps.active_members,
    ps.voter_turnout_rate
FROM communities c
LEFT JOIN LATERAL (
    SELECT * FROM governance_health_indicators
    WHERE community_id = c.id
    ORDER BY calculated_at DESC
    LIMIT 1
) ghi ON true
LEFT JOIN LATERAL (
    SELECT * FROM participation_snapshots
    WHERE community_id = c.id
    ORDER BY snapshot_date DESC
    LIMIT 1
) ps ON true;

CREATE OR REPLACE VIEW participation_trends AS
SELECT 
    community_id,
    snapshot_date,
    total_members,
    active_members,
    ROUND(active_members::DECIMAL / NULLIF(total_members, 0) * 100, 2) AS active_rate,
    votes_cast,
    unique_voters,
    voter_turnout_rate,
    engagement_score,
    LAG(engagement_score) OVER (PARTITION BY community_id ORDER BY snapshot_date) AS prev_engagement,
    engagement_score - LAG(engagement_score) OVER (PARTITION BY community_id ORDER BY snapshot_date) AS engagement_change
FROM participation_snapshots
WHERE snapshot_type = 'daily'
ORDER BY community_id, snapshot_date DESC;

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

INSERT INTO plugins (name, description, version, is_core, is_active, settings_schema)
VALUES (
    'governance_analytics',
    'Aggregate governance analytics including participation metrics, delegation distribution, and decision load tracking. No individual ranking - focuses on community health.',
    '1.0.0',
    false,
    true,
    jsonb_build_object(
        'type', 'object',
        'properties', jsonb_build_object(
            'snapshot_frequency', jsonb_build_object(
                'type', 'string',
                'title', 'Snapshot Frequency',
                'description', 'How often to calculate participation snapshots',
                'enum', ARRAY['hourly', 'daily', 'weekly'],
                'default', 'daily'
            ),
            'health_check_frequency', jsonb_build_object(
                'type', 'string',
                'title', 'Health Check Frequency',
                'description', 'How often to calculate governance health',
                'enum', ARRAY['daily', 'weekly'],
                'default', 'weekly'
            ),
            'retention_days', jsonb_build_object(
                'type', 'integer',
                'title', 'Data Retention',
                'description', 'Days to retain detailed analytics data',
                'default', 365,
                'minimum', 30
            ),
            'public_dashboard', jsonb_build_object(
                'type', 'boolean',
                'title', 'Public Dashboard',
                'description', 'Make analytics dashboard visible to all members',
                'default', true
            )
        )
    )
) ON CONFLICT (name) DO UPDATE SET
    version = EXCLUDED.version,
    description = EXCLUDED.description;