-- B01拥有作品身份、动态档案版本及稳定章节目录。
CREATE TABLE public.muse_work (
    work_id text PRIMARY KEY,
    author_id text NOT NULL,
    current_revision bigint NOT NULL CHECK(current_revision>0),
    directory_revision bigint NOT NULL DEFAULT 0 CHECK(directory_revision>=0)
);
CREATE TABLE public.muse_work_version (
    work_id text NOT NULL REFERENCES public.muse_work(work_id),
    revision bigint NOT NULL CHECK(revision>0),
    content jsonb NOT NULL,
    schema_binding jsonb NOT NULL,
    content_hash text NOT NULL,
    created_at timestamptz NOT NULL DEFAULT clock_timestamp(),
    PRIMARY KEY(work_id,revision)
);
CREATE TABLE public.muse_chapter (
    chapter_id text PRIMARY KEY,
    work_id text NOT NULL REFERENCES public.muse_work(work_id),
    title text NOT NULL,
    position integer NOT NULL CHECK(position>0),
    UNIQUE(work_id,position) DEFERRABLE INITIALLY DEFERRED
);
CREATE TABLE public.muse_directory_version (
    work_id text NOT NULL REFERENCES public.muse_work(work_id),
    revision bigint NOT NULL CHECK(revision>=0),
    chapters jsonb NOT NULL,
    nodes jsonb NOT NULL DEFAULT '[]',
    created_at timestamptz NOT NULL DEFAULT clock_timestamp(),
    PRIMARY KEY(work_id,revision)
);
ALTER TABLE public.muse_work ADD CONSTRAINT work_current_version_fk
    FOREIGN KEY(work_id,current_revision) REFERENCES public.muse_work_version(work_id,revision)
    DEFERRABLE INITIALLY DEFERRED;
ALTER TABLE public.muse_work ADD CONSTRAINT work_current_directory_fk
    FOREIGN KEY(work_id,directory_revision) REFERENCES public.muse_directory_version(work_id,revision)
    DEFERRABLE INITIALLY DEFERRED;
-- 明确选定的探索来源属于B01；保留不可变快照，不将方向选择当作规划确认。
CREATE TABLE public.muse_exploration_selection (
    work_id text PRIMARY KEY REFERENCES public.muse_work(work_id),
    current_revision bigint NOT NULL CHECK(current_revision>0)
);
CREATE TABLE public.muse_exploration_selection_version (
    work_id text NOT NULL REFERENCES public.muse_work(work_id),
    revision bigint NOT NULL CHECK(revision>0),
    snapshot jsonb NOT NULL,
    selected_by text NOT NULL,
    selected_at timestamptz NOT NULL DEFAULT clock_timestamp(),
    PRIMARY KEY(work_id,revision)
);
ALTER TABLE public.muse_exploration_selection ADD CONSTRAINT selection_current_version_fk
    FOREIGN KEY(work_id,current_revision) REFERENCES public.muse_exploration_selection_version(work_id,revision)
    DEFERRABLE INITIALLY DEFERRED;
CREATE TABLE public.muse_plan (
    plan_id text PRIMARY KEY,
    work_id text NOT NULL REFERENCES public.muse_work(work_id),
    type_id text NOT NULL,
    chapter_id text REFERENCES public.muse_chapter(chapter_id),
    node_id text,
    current_revision bigint NOT NULL CHECK(current_revision>0)
);
CREATE TABLE public.muse_plan_version (
    plan_id text NOT NULL REFERENCES public.muse_plan(plan_id),
    revision bigint NOT NULL CHECK(revision>0),
    request jsonb NOT NULL,
    content jsonb NOT NULL,
    content_hash text NOT NULL,
    schema_binding jsonb NOT NULL,
    source_dependencies jsonb NOT NULL,
    author_id text NOT NULL,
    created_at timestamptz NOT NULL DEFAULT clock_timestamp(),
    PRIMARY KEY(plan_id,revision)
);
ALTER TABLE public.muse_plan ADD CONSTRAINT plan_current_version_fk
    FOREIGN KEY(plan_id,current_revision) REFERENCES public.muse_plan_version(plan_id,revision)
    DEFERRABLE INITIALLY DEFERRED;
CREATE TABLE public.muse_plan_candidate (
    candidate_id uuid PRIMARY KEY,
    work_id text NOT NULL REFERENCES public.muse_work(work_id),
    plan_id text NOT NULL,
    current_revision bigint NOT NULL CHECK(current_revision>0)
);
CREATE TABLE public.muse_plan_candidate_version (
    candidate_id uuid NOT NULL REFERENCES public.muse_plan_candidate(candidate_id),
    revision bigint NOT NULL CHECK(revision>0),
    request jsonb NOT NULL,
    content jsonb NOT NULL,
    source_dependencies jsonb NOT NULL,
    candidate_hash text NOT NULL,
    PRIMARY KEY(candidate_id,revision)
);
ALTER TABLE public.muse_plan_candidate ADD CONSTRAINT plan_candidate_current_version_fk
    FOREIGN KEY(candidate_id,current_revision) REFERENCES public.muse_plan_candidate_version(candidate_id,revision)
    DEFERRABLE INITIALLY DEFERRED;