-- This schema supports the phase-1 hybrid proof of concept.
-- The database stores centrally managed configuration only: templates,
-- lookup values, image policy, export settings, and lightweight app flags.
-- Completed reports are intentionally excluded from the server in this phase;
-- they remain browser-local artifacts exported by the client.

CREATE DATABASE IF NOT EXISTS check_list CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

USE check_list;

-- Template identity stays separate from version rows so a single checklist can
-- publish multiple definitions over time while preserving a stable code.
CREATE TABLE IF NOT EXISTS templates (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  code VARCHAR(100) NOT NULL,
  name VARCHAR(200) NOT NULL,
  description TEXT NULL,
  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (id),
  UNIQUE KEY uq_templates_code (code)
);

-- Each template version stores a full JSON definition snapshot. That keeps the
-- frontend contract simple because the client can render a form from one payload
-- without performing additional joins or reconstruction logic.
CREATE TABLE IF NOT EXISTS template_versions (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  template_id BIGINT UNSIGNED NOT NULL,
  version_number INT NOT NULL,
  status ENUM('draft', 'active', 'retired') NOT NULL DEFAULT 'draft',
  definition_json JSON NOT NULL,
  published_at DATETIME NULL,
  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (id),
  UNIQUE KEY uq_template_version (template_id, version_number),
  KEY idx_template_versions_template_status (template_id, status),
  CONSTRAINT fk_template_versions_template
    FOREIGN KEY (template_id) REFERENCES templates (id)
    ON DELETE CASCADE
);

-- Lookup sets support dropdown-style fields in a normalized way. The template
-- JSON references the set by code, while individual values remain editable as
-- data rather than hardcoded frontend options.
CREATE TABLE IF NOT EXISTS lookup_sets (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  code VARCHAR(100) NOT NULL,
  name VARCHAR(200) NOT NULL,
  is_active TINYINT(1) NOT NULL DEFAULT 1,
  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (id),
  UNIQUE KEY uq_lookup_sets_code (code)
);

CREATE TABLE IF NOT EXISTS lookup_values (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  lookup_set_id BIGINT UNSIGNED NOT NULL,
  value VARCHAR(100) NOT NULL,
  label VARCHAR(200) NOT NULL,
  sort_order INT NOT NULL DEFAULT 0,
  is_default TINYINT(1) NOT NULL DEFAULT 0,
  is_active TINYINT(1) NOT NULL DEFAULT 1,
  PRIMARY KEY (id),
  UNIQUE KEY uq_lookup_value (lookup_set_id, value),
  KEY idx_lookup_values_lookup_set (lookup_set_id),
  CONSTRAINT fk_lookup_values_lookup_set
    FOREIGN KEY (lookup_set_id) REFERENCES lookup_sets (id)
    ON DELETE CASCADE
);

-- Image rules are server-managed so administrators can tighten or relax client
-- behavior, such as size limits or attachment counts, without changing browser
-- code. The client reads the active row and enforces it locally.
CREATE TABLE IF NOT EXISTS image_rules (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  code VARCHAR(100) NOT NULL,
  name VARCHAR(200) NOT NULL,
  allowed_mime_types_json JSON NOT NULL,
  max_file_size_bytes INT UNSIGNED NOT NULL,
  max_width_px INT UNSIGNED NOT NULL,
  max_height_px INT UNSIGNED NOT NULL,
  jpeg_quality INT UNSIGNED NOT NULL,
  oversize_behavior ENUM('auto_optimize', 'warn_then_optimize', 'block') NOT NULL DEFAULT 'auto_optimize',
  max_attachments_per_field INT UNSIGNED NOT NULL DEFAULT 5,
  is_active TINYINT(1) NOT NULL DEFAULT 1,
  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (id),
  UNIQUE KEY uq_image_rules_code (code)
);

-- Export profiles represent the eventual shape of the generated ZIP/XLSX output.
-- The current PoC only reads this information, but separating it now makes later
-- export customization easier.
CREATE TABLE IF NOT EXISTS export_profiles (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  code VARCHAR(100) NOT NULL,
  name VARCHAR(200) NOT NULL,
  zip_image_dir VARCHAR(100) NOT NULL DEFAULT 'images',
  excel_sheet_name VARCHAR(100) NOT NULL DEFAULT 'Checklist',
  include_template_version TINYINT(1) NOT NULL DEFAULT 1,
  include_export_timestamp TINYINT(1) NOT NULL DEFAULT 1,
  is_active TINYINT(1) NOT NULL DEFAULT 1,
  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (id),
  UNIQUE KEY uq_export_profiles_code (code)
);

-- Small application settings that do not justify dedicated tables are stored as
-- JSON key/value pairs. This keeps the schema lean during the PoC phase while
-- still allowing centrally managed frontend behavior.
CREATE TABLE IF NOT EXISTS app_config (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  config_key VARCHAR(100) NOT NULL,
  config_value_json JSON NOT NULL,
  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (id),
  UNIQUE KEY uq_app_config_key (config_key)
);

-- Submitted reports are stored server-side for centralized review and archival.
-- The browser creates reports locally first; this table receives them when the
-- operator explicitly submits. The report_uuid links back to the browser-local
-- report ID so resubmissions are idempotent via ON DUPLICATE KEY UPDATE.
CREATE TABLE IF NOT EXISTS reports (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  report_uuid CHAR(36) NOT NULL,
  report_number VARCHAR(100) NOT NULL,
  template_code VARCHAR(100) NOT NULL,
  template_version INT NOT NULL,
  status ENUM('draft', 'in_progress', 'ready_for_export', 'exported', 'archived') NOT NULL DEFAULT 'draft',
  answers_json JSON NOT NULL,
  submitted_at DATETIME NULL,
  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (id),
  UNIQUE KEY uq_reports_uuid (report_uuid),
  KEY idx_reports_template (template_code, template_version),
  KEY idx_reports_status (status)
);

-- The audit log captures every administrative mutation so the team can trace
-- when configuration changed and what the previous value was. Each row stores
-- the entity type, the entity identifier, the action, and JSON snapshots of
-- the old and new values.
CREATE TABLE IF NOT EXISTS audit_log (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  entity_type VARCHAR(100) NOT NULL,
  entity_code VARCHAR(200) NOT NULL,
  action VARCHAR(50) NOT NULL,
  old_value_json JSON NULL,
  new_value_json JSON NULL,
  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (id),
  KEY idx_audit_entity (entity_type, entity_code)
);