coursehub/schema.sql

-- CourseHub schema (MySQL / MariaDB)
CREATE DATABASE IF NOT EXISTS coursehub CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
USE coursehub;

CREATE TABLE IF NOT EXISTS users (
    id            INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    username      VARCHAR(50)  NOT NULL UNIQUE,
    password_hash VARCHAR(255) NOT NULL,
    created_at    TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
) ENGINE=InnoDB;

-- Small key/value store for app-wide facts (currently: when the last scan ran).
CREATE TABLE IF NOT EXISTS app_meta (
    k          VARCHAR(64) PRIMARY KEY,
    v          VARCHAR(255) NOT NULL,
    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
        ON UPDATE CURRENT_TIMESTAMP
) ENGINE=InnoDB;

-- One row per directory found under VIDEOS_ROOT.
-- `path` is the relative path from VIDEOS_ROOT, e.g. "Course 1/Intro".
-- thumbnail_video_id/thumbnail_generated_at are only ever set on top-level
-- (course) folders — see generateThumbnails() — and have no FK to videos
-- (that would make folders<->videos a circular reference); a stale pointer
-- is harmless and self-corrects on the next scan.
CREATE TABLE IF NOT EXISTS folders (
    id                     INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    parent_id              INT UNSIGNED NULL,
    name                   VARCHAR(255) NOT NULL,
    path                   VARCHAR(700) NOT NULL UNIQUE,
    depth                  INT UNSIGNED NOT NULL DEFAULT 0,
    sort_order             INT UNSIGNED NOT NULL DEFAULT 0,
    is_missing             TINYINT(1) NOT NULL DEFAULT 0,
    thumbnail_video_id     INT UNSIGNED NULL,
    thumbnail_generated_at TIMESTAMP NULL,
    created_at             TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
    CONSTRAINT fk_folders_parent FOREIGN KEY (parent_id)
        REFERENCES folders(id) ON DELETE CASCADE,
    INDEX idx_folders_parent (parent_id)
) ENGINE=InnoDB;

CREATE TABLE IF NOT EXISTS videos (
    id               INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    folder_id        INT UNSIGNED NOT NULL,
    name             VARCHAR(255) NOT NULL,   -- display name, filename without .mp4
    filename         VARCHAR(255) NOT NULL,
    path             VARCHAR(700) NOT NULL UNIQUE,  -- relative path incl. filename
    size_bytes       BIGINT UNSIGNED NOT NULL DEFAULT 0,
    duration_seconds FLOAT NULL,              -- filled in by the player on first load
    sort_order       INT UNSIGNED NOT NULL DEFAULT 0,
    is_missing       TINYINT(1) NOT NULL DEFAULT 0,
    created_at       TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
    CONSTRAINT fk_videos_folder FOREIGN KEY (folder_id)
        REFERENCES folders(id) ON DELETE CASCADE,
    INDEX idx_videos_folder (folder_id)
) ENGINE=InnoDB;

-- One row per "*_quiz_solved.txt" file found next to the videos.
-- Questions/options are parsed from the file on demand; only the count is
-- cached here for progress math.
CREATE TABLE IF NOT EXISTS quizzes (
    id            INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    folder_id     INT UNSIGNED NOT NULL,
    name          VARCHAR(255) NOT NULL,   -- filename without the _quiz_solved.txt suffix
    filename      VARCHAR(255) NOT NULL,
    path          VARCHAR(700) NOT NULL UNIQUE,
    num_questions INT UNSIGNED NOT NULL DEFAULT 0,
    sort_order    INT UNSIGNED NOT NULL DEFAULT 0,
    is_missing    TINYINT(1) NOT NULL DEFAULT 0,
    created_at    TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
    CONSTRAINT fk_quizzes_folder FOREIGN KEY (folder_id)
        REFERENCES folders(id) ON DELETE CASCADE,
    INDEX idx_quizzes_folder (folder_id)
) ENGINE=InnoDB;

-- Per-user quiz results. completed = every question answered correctly
-- in a single attempt (sticky).
CREATE TABLE IF NOT EXISTS quiz_progress (
    user_id         INT UNSIGNED NOT NULL,
    quiz_id         INT UNSIGNED NOT NULL,
    best_score      INT UNSIGNED NOT NULL DEFAULT 0,
    last_score      INT UNSIGNED NOT NULL DEFAULT 0,
    total_questions INT UNSIGNED NOT NULL DEFAULT 0,
    attempts        INT UNSIGNED NOT NULL DEFAULT 0,
    completed       TINYINT(1) NOT NULL DEFAULT 0,
    updated_at      TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
        ON UPDATE CURRENT_TIMESTAMP,
    PRIMARY KEY (user_id, quiz_id),
    CONSTRAINT fk_qp_user FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE,
    CONSTRAINT fk_qp_quiz FOREIGN KEY (quiz_id) REFERENCES quizzes(id) ON DELETE CASCADE
) ENGINE=InnoDB;

-- Per-user playback state: resume position + completion flag.
CREATE TABLE IF NOT EXISTS video_progress (
    user_id          INT UNSIGNED NOT NULL,
    video_id         INT UNSIGNED NOT NULL,
    position_seconds FLOAT NOT NULL DEFAULT 0,
    duration_seconds FLOAT NULL,
    completed        TINYINT(1) NOT NULL DEFAULT 0,
    updated_at       TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
        ON UPDATE CURRENT_TIMESTAMP,
    PRIMARY KEY (user_id, video_id),
    CONSTRAINT fk_vp_user  FOREIGN KEY (user_id)  REFERENCES users(id)  ON DELETE CASCADE,
    CONSTRAINT fk_vp_video FOREIGN KEY (video_id) REFERENCES videos(id) ON DELETE CASCADE,
    INDEX idx_vp_user_updated (user_id, updated_at)
) ENGINE=InnoDB;