food-ai/backend/migrations/009_create_translation_tables.sql

-- +goose Up

-- ---------------------------------------------------------------------------
-- recipe_translations
-- Stores per-language overrides for the catalog recipe fields that contain
-- human-readable text (title, description, ingredients list, step descriptions).
-- The base `recipes` row always holds the English (canonical) content.
-- ---------------------------------------------------------------------------
CREATE TABLE recipe_translations (
    recipe_id   UUID        NOT NULL REFERENCES recipes(id) ON DELETE CASCADE,
    lang        VARCHAR(10) NOT NULL,
    title       VARCHAR(500),
    description TEXT,
    ingredients JSONB,
    steps       JSONB,
    PRIMARY KEY (recipe_id, lang)
);

CREATE INDEX idx_recipe_translations_recipe_id ON recipe_translations (recipe_id);

-- ---------------------------------------------------------------------------
-- saved_recipe_translations
-- Stores per-language translations for user-saved (AI-generated) recipes.
-- The base `saved_recipes` row always holds the English canonical content.
-- Translations are generated on demand by the AI layer and recorded here.
-- ---------------------------------------------------------------------------
CREATE TABLE saved_recipe_translations (
    saved_recipe_id UUID        NOT NULL REFERENCES saved_recipes(id) ON DELETE CASCADE,
    lang            VARCHAR(10) NOT NULL,
    title           VARCHAR(500),
    description     TEXT,
    ingredients     JSONB,
    steps           JSONB,
    generated_at    TIMESTAMPTZ NOT NULL DEFAULT now(),
    PRIMARY KEY (saved_recipe_id, lang)
);

CREATE INDEX idx_saved_recipe_translations_recipe_id ON saved_recipe_translations (saved_recipe_id);

-- ---------------------------------------------------------------------------
-- ingredient_translations
-- Stores per-language names (and optional aliases) for ingredient mappings.
-- The base `ingredient_mappings` row holds the English canonical name.
-- ---------------------------------------------------------------------------
CREATE TABLE ingredient_translations (
    ingredient_id UUID        NOT NULL REFERENCES ingredient_mappings(id) ON DELETE CASCADE,
    lang          VARCHAR(10) NOT NULL,
    name          VARCHAR(255) NOT NULL,
    aliases       JSONB        NOT NULL DEFAULT '[]'::jsonb,
    PRIMARY KEY (ingredient_id, lang)
);

CREATE INDEX idx_ingredient_translations_ingredient_id ON ingredient_translations (ingredient_id);

-- ---------------------------------------------------------------------------
-- Migrate existing Russian data from _ru columns into the translation tables.
-- ---------------------------------------------------------------------------

-- Recipe translations: title_ru / description_ru at the row level, plus the
-- embedded name_ru / unit_ru fields inside the ingredients JSONB array, and
-- description_ru inside the steps JSONB array.
INSERT INTO recipe_translations (recipe_id, lang, title, description, ingredients, steps)
SELECT
    id,
    'ru',
    title_ru,
    description_ru,
    -- Rebuild ingredients array with Russian name/unit substituted in.
    CASE
        WHEN jsonb_array_length(ingredients) > 0 THEN (
            SELECT COALESCE(
                jsonb_agg(
                    jsonb_build_object(
                        'spoonacular_id', elem->>'spoonacular_id',
                        'mapping_id',     elem->>'mapping_id',
                        'name',           COALESCE(NULLIF(elem->>'name_ru', ''), elem->>'name'),
                        'amount',         (elem->>'amount')::numeric,
                        'unit',           COALESCE(NULLIF(elem->>'unit_ru', ''), elem->>'unit'),
                        'optional',       (elem->>'optional')::boolean
                    )
                ),
                '[]'::jsonb
            )
            FROM jsonb_array_elements(ingredients) AS elem
        )
        ELSE NULL
    END,
    -- Rebuild steps array with Russian description substituted in.
    CASE
        WHEN jsonb_array_length(steps) > 0 THEN (
            SELECT COALESCE(
                jsonb_agg(
                    jsonb_build_object(
                        'number',        (elem->>'number')::int,
                        'description',   COALESCE(NULLIF(elem->>'description_ru', ''), elem->>'description'),
                        'timer_seconds', elem->'timer_seconds',
                        'image_url',     elem->>'image_url'
                    )
                ),
                '[]'::jsonb
            )
            FROM jsonb_array_elements(steps) AS elem
        )
        ELSE NULL
    END
FROM recipes
WHERE title_ru IS NOT NULL;

-- Ingredient translations: canonical_name_ru.
INSERT INTO ingredient_translations (ingredient_id, lang, name)
SELECT id, 'ru', canonical_name_ru
FROM   ingredient_mappings
WHERE  canonical_name_ru IS NOT NULL;

-- +goose Down
DROP TABLE IF EXISTS ingredient_translations;
DROP TABLE IF EXISTS saved_recipe_translations;
DROP TABLE IF EXISTS recipe_translations;