neiam /gitgud

defmodule GitGud.Repo.Migrations.CreatePullRequests do
  use Ecto.Migration

  def change do
    create table(:pull_requests) do
      add :repository_id, references(:repositories, on_delete: :delete_all), null: false
      add :author_id, references(:users, on_delete: :nilify_all)
      add :number, :integer, null: false
      add :title, :string, null: false, size: 255
      add :body, :text
      # open | closed | merged
      add :state, :string, null: false, default: "open"

      # Branch references (short names). Source = the head; target = where
      # the PR will be merged into.
      add :source_ref, :string, null: false, size: 250
      add :target_ref, :string, null: false, size: 250

      # SHA snapshots — refreshed when the PR is rebased / new commits land.
      add :head_sha, :binary, null: false
      add :base_sha, :binary, null: false

      # Cached mergeability probe.
      # nil = not yet probed; true/false = result of last probe.
      add :mergeable, :boolean
      add :mergeable_checked_at, :utc_datetime

      add :closed_at, :utc_datetime
      add :merged_at, :utc_datetime
      add :merged_by_id, references(:users, on_delete: :nilify_all)
      add :merge_commit_sha, :binary

      timestamps(type: :utc_datetime)
    end

    create unique_index(:pull_requests, [:repository_id, :number])
    create index(:pull_requests, [:repository_id, :state])
    create index(:pull_requests, [:author_id])

    execute """
            ALTER TABLE pull_requests
              ADD COLUMN search_vector tsvector
              GENERATED ALWAYS AS (
                setweight(to_tsvector('english', coalesce(title, '')), 'A') ||
                setweight(to_tsvector('english', coalesce(body, '')), 'B')
              ) STORED;
            """,
            "ALTER TABLE pull_requests DROP COLUMN search_vector;"

    create index(:pull_requests, [:search_vector], using: :gin)

    create table(:pr_comments) do
      add :pull_request_id, references(:pull_requests, on_delete: :delete_all), null: false
      add :author_id, references(:users, on_delete: :nilify_all)
      add :body, :text, null: false
      # Optional inline review anchor — file + line within head_sha.
      # When both are nil, it's a top-level discussion comment.
      add :file_path, :string
      add :line, :integer
      add :commit_sha, :binary

      timestamps(type: :utc_datetime)
    end

    create index(:pr_comments, [:pull_request_id, :inserted_at])

    create table(:pr_reviews) do
      add :pull_request_id, references(:pull_requests, on_delete: :delete_all), null: false
      add :reviewer_id, references(:users, on_delete: :nilify_all), null: false
      # approved | changes_requested | commented
      add :state, :string, null: false
      add :body, :text

      timestamps(type: :utc_datetime)
    end

    create index(:pr_reviews, [:pull_request_id])
  end
end