-- Exercise media library and versioned training-plan content.
-- Apply to an existing database after backing it up.

CREATE TABLE exercises (
    id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    exercise_uuid CHAR(36) NOT NULL UNIQUE,
    slug VARCHAR(100) NOT NULL UNIQUE,
    title_ar VARCHAR(160) NOT NULL,
    title_en VARCHAR(160) NULL,
    instructions_ar JSON NOT NULL,
    target_muscles JSON NOT NULL,
    equipment JSON NOT NULL,
    difficulty ENUM('beginner', 'intermediate', 'advanced') NOT NULL DEFAULT 'beginner',
    movement_type ENUM('strength', 'mobility', 'cardio', 'recovery') NOT NULL,
    gif_url VARCHAR(500) NULL,
    gif_poster_url VARCHAR(500) NULL,
    duration_seconds SMALLINT UNSIGNED NULL,
    repetitions VARCHAR(80) NULL,
    safety_notes_ar JSON NOT NULL,
    alternative_exercise_id BIGINT UNSIGNED NULL,
    is_published BOOLEAN NOT NULL DEFAULT FALSE,
    content_revision INT UNSIGNED NOT NULL DEFAULT 1,
    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    INDEX idx_exercises_public (is_published, movement_type, difficulty),
    CONSTRAINT fk_exercise_alternative FOREIGN KEY (alternative_exercise_id) REFERENCES exercises(id) ON DELETE SET NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

CREATE TABLE training_plans (
    id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    plan_uuid CHAR(36) NOT NULL UNIQUE,
    slug VARCHAR(100) NOT NULL UNIQUE,
    title_ar VARCHAR(160) NOT NULL,
    summary_ar TEXT NOT NULL,
    goal ENUM('general_fitness', 'weight_management', 'mobility', 'endurance') NOT NULL,
    level ENUM('beginner', 'intermediate', 'advanced') NOT NULL,
    weeks_duration TINYINT UNSIGNED NOT NULL,
    source_notes JSON NULL,
    safety_notes_ar JSON NOT NULL,
    is_published BOOLEAN NOT NULL DEFAULT FALSE,
    content_revision INT UNSIGNED NOT NULL DEFAULT 1,
    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    INDEX idx_plans_public (is_published, goal, level)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

CREATE TABLE training_plan_sessions (
    id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    plan_id BIGINT UNSIGNED NOT NULL,
    week_number TINYINT UNSIGNED NOT NULL,
    day_number TINYINT UNSIGNED NOT NULL,
    title_ar VARCHAR(160) NOT NULL,
    session_type ENUM('strength', 'walking', 'mobility', 'rest') NOT NULL,
    duration_minutes SMALLINT UNSIGNED NOT NULL DEFAULT 0,
    intensity ENUM('easy', 'moderate', 'vigorous') NOT NULL DEFAULT 'easy',
    notes_ar TEXT NULL,
    sort_order SMALLINT UNSIGNED NOT NULL DEFAULT 0,
    UNIQUE KEY uq_plan_week_day (plan_id, week_number, day_number),
    CONSTRAINT fk_plan_sessions_plan FOREIGN KEY (plan_id) REFERENCES training_plans(id) ON DELETE CASCADE,
    INDEX idx_plan_sessions_order (plan_id, week_number, sort_order)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

CREATE TABLE training_session_exercises (
    session_id BIGINT UNSIGNED NOT NULL,
    exercise_id BIGINT UNSIGNED NOT NULL,
    sort_order SMALLINT UNSIGNED NOT NULL DEFAULT 0,
    sets TINYINT UNSIGNED NULL,
    reps VARCHAR(60) NULL,
    duration_seconds SMALLINT UNSIGNED NULL,
    rest_seconds SMALLINT UNSIGNED NOT NULL DEFAULT 45,
    PRIMARY KEY (session_id, exercise_id),
    CONSTRAINT fk_session_exercises_session FOREIGN KEY (session_id) REFERENCES training_plan_sessions(id) ON DELETE CASCADE,
    CONSTRAINT fk_session_exercises_exercise FOREIGN KEY (exercise_id) REFERENCES exercises(id) ON DELETE RESTRICT
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;