-- 数据演进：隔离目标身份与迁移来源/回执；不代替任何业务域的实体或候选表。
CREATE TABLE public.muse_legacy_target (
    singleton boolean PRIMARY KEY DEFAULT true CHECK (singleton),
    target_id uuid NOT NULL UNIQUE,
    system_identifier text NOT NULL,
    data_directory text NOT NULL,
    host text NOT NULL,
    port integer NOT NULL CHECK (port BETWEEN 1 AND 65535),
    database_name text NOT NULL,
    database_oid oid NOT NULL,
    role_name text NOT NULL CHECK (role_name='muse_app'),
    run_purpose public.muse_purpose NOT NULL CHECK (run_purpose='production'),
    created_at timestamptz NOT NULL DEFAULT clock_timestamp()
);
-- 应用角色不能把任意已有库自行标为隔离目标。
REVOKE ALL ON public.muse_legacy_target FROM muse_app, muse_eval;
GRANT SELECT ON public.muse_legacy_target TO muse_app;

CREATE TABLE public.muse_legacy_import_record (
    author_id text NOT NULL,
    run_purpose public.muse_purpose NOT NULL CHECK (run_purpose='production'),
    source_key text NOT NULL CHECK (length(source_key)>0),
    source_hash text NOT NULL CHECK (source_hash ~ '^[0-9a-f]{64}$'),
    mapping_hash text NOT NULL CHECK (mapping_hash ~ '^[0-9a-f]{64}$'),
    original jsonb NOT NULL CHECK (jsonb_typeof(original)='object'),
    command_id text NOT NULL,
    route jsonb NOT NULL CHECK (jsonb_typeof(route)='object'),
    frozen_request jsonb,
    state text NOT NULL DEFAULT 'reserved'
        CHECK (state IN ('reserved','mapped','historical','quarantined')),
    reason_code text NOT NULL DEFAULT '',
    targets jsonb NOT NULL DEFAULT '[]'::jsonb CHECK (jsonb_typeof(targets)='array'),
    receipt jsonb,
    created_at timestamptz NOT NULL DEFAULT clock_timestamp(),
    updated_at timestamptz NOT NULL DEFAULT clock_timestamp(),
    PRIMARY KEY (author_id, source_key),
    UNIQUE (author_id, command_id),
    CHECK (state <> 'mapped' OR
           (frozen_request IS NOT NULL AND receipt IS NOT NULL AND jsonb_array_length(targets)>0)),
    CHECK (state = 'mapped' OR (receipt IS NULL AND targets='[]'::jsonb))
);

REVOKE DELETE ON public.muse_legacy_import_record FROM muse_app;

CREATE FUNCTION public.muse_guard_legacy_import_record() RETURNS trigger
LANGUAGE plpgsql AS $$
BEGIN
    IF (NEW.author_id, NEW.run_purpose, NEW.source_key, NEW.source_hash,
        NEW.mapping_hash, NEW.original, NEW.command_id, NEW.route)
       IS DISTINCT FROM
       (OLD.author_id, OLD.run_purpose, OLD.source_key, OLD.source_hash,
        OLD.mapping_hash, OLD.original, OLD.command_id, OLD.route) THEN
        RAISE EXCEPTION '迁移来源、映射与命令身份不可改写';
    END IF;
    IF OLD.frozen_request IS NOT NULL AND NEW.frozen_request IS DISTINCT FROM OLD.frozen_request THEN
        RAISE EXCEPTION '迁移目标请求已经冻结';
    END IF;
    IF OLD.state <> 'reserved' AND
       (NEW.state, NEW.reason_code, NEW.targets, NEW.receipt, NEW.frozen_request)
       IS DISTINCT FROM
       (OLD.state, OLD.reason_code, OLD.targets, OLD.receipt, OLD.frozen_request) THEN
        RAISE EXCEPTION '迁移终态及回执不可改写';
    END IF;
    NEW.updated_at := clock_timestamp();
    RETURN NEW;
END;
$$;
CREATE TRIGGER muse_legacy_import_record_guard
BEFORE UPDATE ON public.muse_legacy_import_record
FOR EACH ROW EXECUTE FUNCTION public.muse_guard_legacy_import_record();