-- ============================================================================
-- Migration 042 — A4 Fase 4.2: Competenze (skill / requisiti ruolo / competenze
-- possedute / mappatura corsi) + base per gap competenze e alert->azione.
-- ----------------------------------------------------------------------------
-- 4 tabelle ADDITIVE. Idempotente (CREATE TABLE IF NOT EXISTS). Applicare con la
-- STESSA connessione PDO dell'app (host MySQL servito da php-fpm), via runner.
--
-- Ancoraggio normativo (docs/DESIGN_A4_RELATIONAL.md sez.3/4): PR.AT-01 (tutti),
-- PR.AT-02 (solo soggetti essenziali), GV.RR-04 (cyber nelle pratiche HR).
--
-- NOTA architetturale: l'alert "gap competenza -> azione" RIUSA il workflow
-- NCR/CAPA gia esistente (tabelle non_conformities + capa_actions, mig.004).
-- NON esiste alcuna tabella 'corrective_actions' (nome errato nel design): le
-- azioni sono capa_actions, figlie obbligatorie di una non_conformity. Quindi
-- questa migration NON crea/altera tabelle azioni: ancora il gap alla NCR via
-- non_conformities.source_entity_type='competence_gap' + source_entity_id.
-- ============================================================================

-- Catalogo competenze. organization_id NULL = competenza globale di sistema
-- (visibile a tutte le org, come i corsi globali).
CREATE TABLE IF NOT EXISTS skills (
    id INT AUTO_INCREMENT PRIMARY KEY,
    organization_id INT NULL,
    name VARCHAR(150) NOT NULL,
    area VARCHAR(100) NULL,
    description TEXT NULL,
    created_by INT NULL,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (organization_id) REFERENCES organizations(id) ON DELETE CASCADE,
    FOREIGN KEY (created_by) REFERENCES users(id) ON DELETE SET NULL,
    INDEX idx_skills_org (organization_id),
    INDEX idx_skills_area (area)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

-- Competenze RICHIESTE da un ruolo dell'organigramma (m2m ruolo<->skill).
CREATE TABLE IF NOT EXISTS role_skills (
    id INT AUTO_INCREMENT PRIMARY KEY,
    organization_id INT NOT NULL,
    role_id INT NOT NULL,
    skill_id INT NOT NULL,
    required_level TINYINT NOT NULL DEFAULT 3,
    created_by INT NULL,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (organization_id) REFERENCES organizations(id) ON DELETE CASCADE,
    FOREIGN KEY (role_id) REFERENCES org_roles(id) ON DELETE CASCADE,
    FOREIGN KEY (skill_id) REFERENCES skills(id) ON DELETE CASCADE,
    FOREIGN KEY (created_by) REFERENCES users(id) ON DELETE SET NULL,
    UNIQUE KEY uk_role_skill (role_id, skill_id),
    INDEX idx_role_skills_org (organization_id),
    INDEX idx_role_skills_skill (skill_id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

-- Competenze POSSEDUTE da un utente (m2m utente<->skill). acquired_via_course_id
-- collega eventualmente la competenza al corso che l'ha erogata (registro corsi).
CREATE TABLE IF NOT EXISTS user_skills (
    id INT AUTO_INCREMENT PRIMARY KEY,
    organization_id INT NOT NULL,
    user_id INT NOT NULL,
    skill_id INT NOT NULL,
    level TINYINT NOT NULL DEFAULT 1,
    acquired_via_course_id INT NULL,
    evidence VARCHAR(500) NULL,
    assessed_at DATETIME NULL,
    created_by INT NULL,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (organization_id) REFERENCES organizations(id) ON DELETE CASCADE,
    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE,
    FOREIGN KEY (skill_id) REFERENCES skills(id) ON DELETE CASCADE,
    FOREIGN KEY (acquired_via_course_id) REFERENCES training_courses(id) ON DELETE SET NULL,
    FOREIGN KEY (created_by) REFERENCES users(id) ON DELETE SET NULL,
    UNIQUE KEY uk_user_skill (organization_id, user_id, skill_id),
    INDEX idx_user_skills_user (user_id),
    INDEX idx_user_skills_skill (skill_id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

-- Mappatura competenza <-> corso che la eroga (m2m). Il corso puo essere globale
-- (training_courses.organization_id NULL) o dell'org.
CREATE TABLE IF NOT EXISTS skill_course_map (
    id INT AUTO_INCREMENT PRIMARY KEY,
    skill_id INT NOT NULL,
    training_course_id INT NOT NULL,
    created_by INT NULL,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (skill_id) REFERENCES skills(id) ON DELETE CASCADE,
    FOREIGN KEY (training_course_id) REFERENCES training_courses(id) ON DELETE CASCADE,
    FOREIGN KEY (created_by) REFERENCES users(id) ON DELETE SET NULL,
    UNIQUE KEY uk_skill_course (skill_id, training_course_id),
    INDEX idx_skill_course_course (training_course_id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;