import type Database from 'better-sqlite3';
import type { Ingredient, Recipe, Step } from '$lib/types';

type RecipeRow = {
  id: number;
  title: string;
  description: string | null;
  source_url: string | null;
  source_domain: string | null;
  image_path: string | null;
  servings_default: number | null;
  servings_unit: string | null;
  prep_time_min: number | null;
  cook_time_min: number | null;
  total_time_min: number | null;
  cuisine: string | null;
  category: string | null;
};

function ensureTagIds(db: Database.Database, names: string[]): number[] {
  const insert = db.prepare('INSERT OR IGNORE INTO tag(name) VALUES (?)');
  const select = db.prepare('SELECT id FROM tag WHERE name = ?');
  const ids: number[] = [];
  for (const name of names) {
    const trimmed = name.trim();
    if (!trimmed) continue;
    insert.run(trimmed);
    const row = select.get(trimmed) as { id: number };
    ids.push(row.id);
  }
  return ids;
}

function refreshFts(db: Database.Database, recipeId: number): void {
  // Trigger the AFTER UPDATE trigger which rebuilds the FTS row with current ingredients + tags.
  db.prepare('UPDATE recipe SET title = title WHERE id = ?').run(recipeId);
}

export function insertRecipe(db: Database.Database, recipe: Recipe): number {
  const tx = db.transaction((): number => {
    const info = db
      .prepare(
        `INSERT INTO recipe
          (title, description, source_url, source_domain, image_path,
           servings_default, servings_unit,
           prep_time_min, cook_time_min, total_time_min,
           cuisine, category)
         VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`
      )
      .run(
        recipe.title,
        recipe.description,
        recipe.source_url,
        recipe.source_domain,
        recipe.image_path,
        recipe.servings_default,
        recipe.servings_unit,
        recipe.prep_time_min,
        recipe.cook_time_min,
        recipe.total_time_min,
        recipe.cuisine,
        recipe.category
      );
    const id = Number(info.lastInsertRowid);

    const insIng = db.prepare(
      `INSERT INTO ingredient(recipe_id, position, quantity, unit, name, note, raw_text, section_heading)
       VALUES (?, ?, ?, ?, ?, ?, ?, ?)`
    );
    for (const ing of recipe.ingredients) {
      insIng.run(id, ing.position, ing.quantity, ing.unit, ing.name, ing.note, ing.raw_text, ing.section_heading);
    }

    const insStep = db.prepare(
      'INSERT INTO step(recipe_id, position, text) VALUES (?, ?, ?)'
    );
    for (const step of recipe.steps) {
      insStep.run(id, step.position, step.text);
    }

    const tagIds = ensureTagIds(db, recipe.tags);
    const linkTag = db.prepare(
      'INSERT OR IGNORE INTO recipe_tag(recipe_id, tag_id) VALUES (?, ?)'
    );
    for (const tid of tagIds) linkTag.run(id, tid);

    refreshFts(db, id);
    return id;
  });
  return tx();
}

export function getRecipeById(db: Database.Database, id: number): Recipe | null {
  const row = db
    .prepare(
      `SELECT id, title, description, source_url, source_domain, image_path,
              servings_default, servings_unit,
              prep_time_min, cook_time_min, total_time_min,
              cuisine, category
         FROM recipe WHERE id = ?`
    )
    .get(id) as RecipeRow | undefined;
  if (!row) return null;

  const ingredients = db
    .prepare(
      `SELECT position, quantity, unit, name, note, raw_text, section_heading
         FROM ingredient WHERE recipe_id = ? ORDER BY position`
    )
    .all(id) as Ingredient[];

  const steps = db
    .prepare('SELECT position, text FROM step WHERE recipe_id = ? ORDER BY position')
    .all(id) as Step[];

  const tagRows = db
    .prepare(
      `SELECT t.name FROM tag t
         JOIN recipe_tag rt ON rt.tag_id = t.id
        WHERE rt.recipe_id = ?
        ORDER BY t.name`
    )
    .all(id) as { name: string }[];

  return {
    id: row.id,
    title: row.title,
    description: row.description,
    source_url: row.source_url,
    source_domain: row.source_domain,
    image_path: row.image_path,
    servings_default: row.servings_default,
    servings_unit: row.servings_unit,
    prep_time_min: row.prep_time_min,
    cook_time_min: row.cook_time_min,
    total_time_min: row.total_time_min,
    cuisine: row.cuisine,
    category: row.category,
    ingredients,
    steps,
    tags: tagRows.map((t) => t.name)
  };
}

export function getRecipeIdBySourceUrl(
  db: Database.Database,
  url: string
): number | null {
  const row = db.prepare('SELECT id FROM recipe WHERE source_url = ?').get(url) as
    | { id: number }
    | undefined;
  return row?.id ?? null;
}

export function deleteRecipe(db: Database.Database, id: number): void {
  db.prepare('DELETE FROM recipe WHERE id = ?').run(id);
}

export type RecipeMetaPatch = {
  title?: string;
  description?: string | null;
  servings_default?: number | null;
  servings_unit?: string | null;
  prep_time_min?: number | null;
  cook_time_min?: number | null;
  total_time_min?: number | null;
  cuisine?: string | null;
  category?: string | null;
};

export function updateRecipeMeta(
  db: Database.Database,
  id: number,
  patch: RecipeMetaPatch
): void {
  const fields: string[] = [];
  const values: unknown[] = [];
  for (const key of [
    'title',
    'description',
    'servings_default',
    'servings_unit',
    'prep_time_min',
    'cook_time_min',
    'total_time_min',
    'cuisine',
    'category'
  ] as const) {
    if (patch[key] !== undefined) {
      fields.push(`${key} = ?`);
      values.push(patch[key]);
    }
  }
  if (fields.length === 0) return;
  fields.push('updated_at = CURRENT_TIMESTAMP');
  db.prepare(`UPDATE recipe SET ${fields.join(', ')} WHERE id = ?`).run(...values, id);
}

export function updateImagePath(
  db: Database.Database,
  id: number,
  filename: string | null
): void {
  db.prepare('UPDATE recipe SET image_path = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?').run(
    filename,
    id
  );
}

export function replaceIngredients(
  db: Database.Database,
  recipeId: number,
  ingredients: Ingredient[]
): void {
  const tx = db.transaction(() => {
    db.prepare('DELETE FROM ingredient WHERE recipe_id = ?').run(recipeId);
    const ins = db.prepare(
      `INSERT INTO ingredient(recipe_id, position, quantity, unit, name, note, raw_text, section_heading)
       VALUES (?, ?, ?, ?, ?, ?, ?, ?)`
    );
    for (const ing of ingredients) {
      ins.run(recipeId, ing.position, ing.quantity, ing.unit, ing.name, ing.note, ing.raw_text, ing.section_heading);
    }
    refreshFts(db, recipeId);
  });
  tx();
}

export function replaceSteps(
  db: Database.Database,
  recipeId: number,
  steps: Step[]
): void {
  const tx = db.transaction(() => {
    db.prepare('DELETE FROM step WHERE recipe_id = ?').run(recipeId);
    const ins = db.prepare(
      'INSERT INTO step(recipe_id, position, text) VALUES (?, ?, ?)'
    );
    for (const step of steps) {
      ins.run(recipeId, step.position, step.text);
    }
  });
  tx();
}