-- RBAC System Migration for PostgreSQL
-- Migration: 003_rbac_system
-- Database: PostgreSQL

-- User categories table
CREATE TABLE IF NOT EXISTS user_categories (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    name VARCHAR(100) NOT NULL UNIQUE,
    description TEXT,
    parent_id UUID REFERENCES user_categories(id) ON DELETE CASCADE,
    metadata JSONB,
    is_active BOOLEAN NOT NULL DEFAULT true,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

-- User tags table
CREATE TABLE IF NOT EXISTS user_tags (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    name VARCHAR(100) NOT NULL UNIQUE,
    description TEXT,
    color VARCHAR(7), -- hex color code
    metadata JSONB,
    is_active BOOLEAN NOT NULL DEFAULT true,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

-- User category assignments
CREATE TABLE IF NOT EXISTS user_category_assignments (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    category_id UUID NOT NULL REFERENCES user_categories(id) ON DELETE CASCADE,
    assigned_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    assigned_by UUID REFERENCES users(id),
    expires_at TIMESTAMPTZ,
    UNIQUE(user_id, category_id)
);

-- User tag assignments
CREATE TABLE IF NOT EXISTS user_tag_assignments (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    tag_id UUID NOT NULL REFERENCES user_tags(id) ON DELETE CASCADE,
    assigned_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    assigned_by UUID REFERENCES users(id),
    expires_at TIMESTAMPTZ,
    UNIQUE(user_id, tag_id)
);

-- Access rules table
CREATE TABLE IF NOT EXISTS access_rules (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    name VARCHAR(255) NOT NULL,
    description TEXT,
    resource_type VARCHAR(50) NOT NULL, -- 'database', 'file', 'directory', 'content', 'api'
    resource_name VARCHAR(500) NOT NULL, -- supports wildcards
    action VARCHAR(50) NOT NULL, -- 'read', 'write', 'delete', 'execute'
    priority INTEGER NOT NULL DEFAULT 0, -- higher priority rules evaluated first
    is_active BOOLEAN NOT NULL DEFAULT true,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

-- Role requirements for access rules
CREATE TABLE IF NOT EXISTS access_rule_roles (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    rule_id UUID NOT NULL REFERENCES access_rules(id) ON DELETE CASCADE,
    role_id UUID NOT NULL REFERENCES user_roles(id) ON DELETE CASCADE,
    UNIQUE(rule_id, role_id)
);

-- Permission requirements for access rules
CREATE TABLE IF NOT EXISTS access_rule_permissions (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    rule_id UUID NOT NULL REFERENCES access_rules(id) ON DELETE CASCADE,
    permission_name VARCHAR(100) NOT NULL,
    resource_scope VARCHAR(255), -- optional scope for permission
    UNIQUE(rule_id, permission_name, resource_scope)
);

-- Category requirements for access rules
CREATE TABLE IF NOT EXISTS access_rule_categories (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    rule_id UUID NOT NULL REFERENCES access_rules(id) ON DELETE CASCADE,
    category_id UUID NOT NULL REFERENCES user_categories(id) ON DELETE CASCADE,
    requirement_type VARCHAR(20) NOT NULL DEFAULT 'required', -- 'required', 'denied'
    UNIQUE(rule_id, category_id, requirement_type)
);

-- Tag requirements for access rules
CREATE TABLE IF NOT EXISTS access_rule_tags (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    rule_id UUID NOT NULL REFERENCES access_rules(id) ON DELETE CASCADE,
    tag_id UUID NOT NULL REFERENCES user_tags(id) ON DELETE CASCADE,
    requirement_type VARCHAR(20) NOT NULL DEFAULT 'required', -- 'required', 'denied'
    UNIQUE(rule_id, tag_id, requirement_type)
);

-- Permission cache for performance
CREATE TABLE IF NOT EXISTS user_permission_cache (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    resource_type VARCHAR(50) NOT NULL,
    resource_name VARCHAR(500) NOT NULL,
    action VARCHAR(50) NOT NULL,
    access_result VARCHAR(20) NOT NULL, -- 'allow', 'deny', 'require_additional_auth'
    cache_key VARCHAR(255) NOT NULL,
    expires_at TIMESTAMPTZ NOT NULL,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE(user_id, cache_key)
);

-- RBAC configuration table for storing TOML configs
CREATE TABLE IF NOT EXISTS rbac_configs (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    name VARCHAR(100) NOT NULL UNIQUE,
    description TEXT,
    config_data JSONB NOT NULL,
    is_active BOOLEAN NOT NULL DEFAULT true,
    version INTEGER NOT NULL DEFAULT 1,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

-- Audit log for access attempts
CREATE TABLE IF NOT EXISTS access_audit_log (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    user_id UUID REFERENCES users(id) ON DELETE SET NULL,
    resource_type VARCHAR(50) NOT NULL,
    resource_name VARCHAR(500) NOT NULL,
    action VARCHAR(50) NOT NULL,
    access_result VARCHAR(20) NOT NULL,
    rule_id UUID REFERENCES access_rules(id) ON DELETE SET NULL,
    ip_address INET,
    user_agent TEXT,
    session_id VARCHAR(255),
    additional_context JSONB,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

-- Create indexes for performance
CREATE INDEX IF NOT EXISTS idx_user_categories_name ON user_categories(name);
CREATE INDEX IF NOT EXISTS idx_user_categories_parent ON user_categories(parent_id);
CREATE INDEX IF NOT EXISTS idx_user_categories_active ON user_categories(is_active);

CREATE INDEX IF NOT EXISTS idx_user_tags_name ON user_tags(name);
CREATE INDEX IF NOT EXISTS idx_user_tags_active ON user_tags(is_active);

CREATE INDEX IF NOT EXISTS idx_user_category_assignments_user ON user_category_assignments(user_id);
CREATE INDEX IF NOT EXISTS idx_user_category_assignments_category ON user_category_assignments(category_id);
CREATE INDEX IF NOT EXISTS idx_user_category_assignments_expires ON user_category_assignments(expires_at);

CREATE INDEX IF NOT EXISTS idx_user_tag_assignments_user ON user_tag_assignments(user_id);
CREATE INDEX IF NOT EXISTS idx_user_tag_assignments_tag ON user_tag_assignments(tag_id);
CREATE INDEX IF NOT EXISTS idx_user_tag_assignments_expires ON user_tag_assignments(expires_at);

CREATE INDEX IF NOT EXISTS idx_access_rules_resource ON access_rules(resource_type, resource_name);
CREATE INDEX IF NOT EXISTS idx_access_rules_action ON access_rules(action);
CREATE INDEX IF NOT EXISTS idx_access_rules_priority ON access_rules(priority DESC);
CREATE INDEX IF NOT EXISTS idx_access_rules_active ON access_rules(is_active);

CREATE INDEX IF NOT EXISTS idx_access_rule_roles_rule ON access_rule_roles(rule_id);
CREATE INDEX IF NOT EXISTS idx_access_rule_roles_role ON access_rule_roles(role_id);

CREATE INDEX IF NOT EXISTS idx_access_rule_permissions_rule ON access_rule_permissions(rule_id);
CREATE INDEX IF NOT EXISTS idx_access_rule_permissions_name ON access_rule_permissions(permission_name);

CREATE INDEX IF NOT EXISTS idx_access_rule_categories_rule ON access_rule_categories(rule_id);
CREATE INDEX IF NOT EXISTS idx_access_rule_categories_category ON access_rule_categories(category_id);

CREATE INDEX IF NOT EXISTS idx_access_rule_tags_rule ON access_rule_tags(rule_id);
CREATE INDEX IF NOT EXISTS idx_access_rule_tags_tag ON access_rule_tags(tag_id);

CREATE INDEX IF NOT EXISTS idx_user_permission_cache_user ON user_permission_cache(user_id);
CREATE INDEX IF NOT EXISTS idx_user_permission_cache_key ON user_permission_cache(cache_key);
CREATE INDEX IF NOT EXISTS idx_user_permission_cache_expires ON user_permission_cache(expires_at);

CREATE INDEX IF NOT EXISTS idx_rbac_configs_name ON rbac_configs(name);
CREATE INDEX IF NOT EXISTS idx_rbac_configs_active ON rbac_configs(is_active);

CREATE INDEX IF NOT EXISTS idx_access_audit_log_user ON access_audit_log(user_id);
CREATE INDEX IF NOT EXISTS idx_access_audit_log_resource ON access_audit_log(resource_type, resource_name);
CREATE INDEX IF NOT EXISTS idx_access_audit_log_created ON access_audit_log(created_at);

-- Add triggers for updated_at columns
CREATE TRIGGER update_user_categories_updated_at
    BEFORE UPDATE ON user_categories
    FOR EACH ROW EXECUTE FUNCTION update_updated_at_column();

CREATE TRIGGER update_user_tags_updated_at
    BEFORE UPDATE ON user_tags
    FOR EACH ROW EXECUTE FUNCTION update_updated_at_column();

CREATE TRIGGER update_access_rules_updated_at
    BEFORE UPDATE ON access_rules
    FOR EACH ROW EXECUTE FUNCTION update_updated_at_column();

CREATE TRIGGER update_rbac_configs_updated_at
    BEFORE UPDATE ON rbac_configs
    FOR EACH ROW EXECUTE FUNCTION update_updated_at_column();

-- Function to clean up expired permission cache
CREATE OR REPLACE FUNCTION cleanup_expired_permission_cache()
RETURNS INTEGER AS $$
DECLARE
    deleted_count INTEGER;
BEGIN
    DELETE FROM user_permission_cache WHERE expires_at < NOW();
    GET DIAGNOSTICS deleted_count = ROW_COUNT;
    RETURN deleted_count;
END;
$$ LANGUAGE plpgsql;

-- Function to get user categories (including inherited)
CREATE OR REPLACE FUNCTION get_user_categories(user_uuid UUID)
RETURNS TABLE(category_name VARCHAR(100)) AS $$
BEGIN
    RETURN QUERY
    WITH RECURSIVE category_tree AS (
        -- Direct categories
        SELECT uc.name, uc.parent_id
        FROM user_categories uc
        JOIN user_category_assignments uca ON uc.id = uca.category_id
        WHERE uca.user_id = user_uuid
          AND uc.is_active = true
          AND (uca.expires_at IS NULL OR uca.expires_at > NOW())

        UNION ALL

        -- Parent categories
        SELECT uc.name, uc.parent_id
        FROM user_categories uc
        JOIN category_tree ct ON uc.id = ct.parent_id
        WHERE uc.is_active = true
    )
    SELECT DISTINCT ct.name
    FROM category_tree ct;
END;
$$ LANGUAGE plpgsql;

-- Function to get user tags
CREATE OR REPLACE FUNCTION get_user_tags(user_uuid UUID)
RETURNS TABLE(tag_name VARCHAR(100)) AS $$
BEGIN
    RETURN QUERY
    SELECT ut.name
    FROM user_tags ut
    JOIN user_tag_assignments uta ON ut.id = uta.tag_id
    WHERE uta.user_id = user_uuid
      AND ut.is_active = true
      AND (uta.expires_at IS NULL OR uta.expires_at > NOW());
END;
$$ LANGUAGE plpgsql;

-- Insert default categories
INSERT INTO user_categories (name, description) VALUES
('admin', 'Administrative access category'),
('editor', 'Content editing access category'),
('viewer', 'Read-only access category'),
('finance', 'Financial data access category'),
('hr', 'Human resources access category'),
('it', 'Information technology access category')
ON CONFLICT (name) DO NOTHING;

-- Insert default tags
INSERT INTO user_tags (name, description, color) VALUES
('sensitive', 'Access to sensitive data', '#ff0000'),
('public', 'Public data access', '#00ff00'),
('internal', 'Internal data access', '#ffff00'),
('confidential', 'Confidential data access', '#ff8800'),
('restricted', 'Restricted access', '#8800ff'),
('temporary', 'Temporary access', '#00ffff')
ON CONFLICT (name) DO NOTHING;

-- Insert default RBAC configuration
INSERT INTO rbac_configs (name, description, config_data) VALUES
('default', 'Default RBAC configuration', '{
    "rules": [
        {
            "id": "admin_full_access",
            "resource_type": "Database",
            "resource_name": "*",
            "allowed_roles": ["Admin"],
            "allowed_permissions": [],
            "required_categories": [],
            "required_tags": [],
            "deny_categories": [],
            "deny_tags": [],
            "is_active": true
        },
        {
            "id": "editor_content_access",
            "resource_type": "Database",
            "resource_name": "content*",
            "allowed_roles": ["Editor"],
            "allowed_permissions": ["WriteContent"],
            "required_categories": ["editor"],
            "required_tags": [],
            "deny_categories": [],
            "deny_tags": ["restricted"],
            "is_active": true
        }
    ],
    "default_permissions": {
        "Database": ["ReadContent"],
        "File": ["ReadFile"]
    },
    "category_hierarchies": {
        "admin": ["editor", "viewer"],
        "editor": ["viewer"]
    },
    "tag_hierarchies": {
        "public": ["internal"],
        "internal": ["confidential"],
        "confidential": ["restricted"]
    },
    "cache_ttl_seconds": 300
}')
ON CONFLICT (name) DO NOTHING;