-- +goose Up
-- Layout modules: what each area of a blog (header, columns, footer) shows.
CREATE TABLE modules (
    id          bigserial PRIMARY KEY,
    blog_id     bigint NOT NULL REFERENCES blogs(id) ON DELETE CASCADE,
    area        text NOT NULL CHECK (area IN ('header', 'left', 'right', 'above', 'below', 'footer')),
    kind        text NOT NULL CHECK (kind IN ('title', 'logo', 'menu', 'archive', 'recent', 'html', 'rss', 'text', 'sitemap')),
    title       text NOT NULL DEFAULT '',
    body        text NOT NULL DEFAULT '',
    count       integer NOT NULL DEFAULT 5,
    sort_order  integer NOT NULL DEFAULT 0,
    created_at  timestamptz NOT NULL DEFAULT now(),
    updated_at  timestamptz NOT NULL DEFAULT now()
);
CREATE INDEX modules_blog ON modules (blog_id, area, sort_order, id);

-- The menu: blog pages and custom links in one ordered list.
CREATE TABLE menu_items (
    id          bigserial PRIMARY KEY,
    blog_id     bigint NOT NULL REFERENCES blogs(id) ON DELETE CASCADE,
    page_id     bigint REFERENCES pages(id) ON DELETE CASCADE,
    label       text NOT NULL DEFAULT '',
    url         text NOT NULL DEFAULT '',
    sort_order  integer NOT NULL DEFAULT 0,
    CHECK (page_id IS NOT NULL OR url <> '')
);
CREATE UNIQUE INDEX menu_items_page ON menu_items (page_id) WHERE page_id IS NOT NULL;
CREATE INDEX menu_items_blog ON menu_items (blog_id, sort_order, id);

-- Existing blogs keep the menu they had: pages marked "show in menu", in menu
-- order, with the home page only if the theme included it.
INSERT INTO menu_items (blog_id, page_id, sort_order)
SELECT p.blog_id, p.id, row_number() OVER (PARTITION BY p.blog_id ORDER BY p.nav_order, p.id) - 1
FROM pages p JOIN blogs b ON b.id = p.blog_id
WHERE p.show_in_nav AND (NOT p.is_home OR coalesce((b.theme->>'nav_show_home')::boolean, true));
ALTER TABLE pages DROP COLUMN show_in_nav;

-- ...and the layout their theme described.
INSERT INTO modules (blog_id, area, kind, sort_order)
SELECT id, 'header', 'title', CASE WHEN theme->>'nav_position' = 'top-bar' THEN 1 ELSE 0 END
FROM blogs WHERE coalesce((theme->>'header_show_title')::boolean, true);
INSERT INTO modules (blog_id, area, kind, sort_order)
SELECT id, 'header', 'menu', CASE WHEN theme->>'nav_position' = 'top-bar' THEN 0 ELSE 1 END
FROM blogs WHERE coalesce(theme->>'nav_position', 'below-header') <> 'left-sidebar';
INSERT INTO modules (blog_id, area, kind, sort_order)
SELECT id, 'left', 'menu', 0 FROM blogs WHERE theme->>'nav_position' = 'left-sidebar';
INSERT INTO modules (blog_id, area, kind, body, sort_order)
SELECT id, 'footer', 'text', theme->>'footer_text', 0 FROM blogs WHERE coalesce(theme->>'footer_text', '') <> '';
INSERT INTO modules (blog_id, area, kind, sort_order)
SELECT id, 'footer', 'rss', 1 FROM blogs WHERE coalesce((theme->>'footer_show_rss')::boolean, true);

-- +goose Down
ALTER TABLE pages ADD COLUMN show_in_nav boolean NOT NULL DEFAULT true;
UPDATE pages SET show_in_nav = EXISTS (SELECT 1 FROM menu_items m WHERE m.page_id = pages.id);
DROP TABLE menu_items;
DROP TABLE modules;