-- Pivot Forecast schema install
-- Run once against target database: psql -d <db> -f setup_sql/01_schema.sql

CREATE SCHEMA IF NOT EXISTS pf;

CREATE TABLE IF NOT EXISTS pf.source (
    id             serial PRIMARY KEY,
    schema         text NOT NULL,
    tname          text NOT NULL,
    label          text,
    status         text NOT NULL DEFAULT 'active',  -- active | archived
    default_layout jsonb,                            -- Perspective view config used as the per-source default
    created_at     timestamptz NOT NULL DEFAULT now(),
    created_by     text,
    UNIQUE (schema, tname)
);

-- backfill columns for existing installs
ALTER TABLE pf.source ADD COLUMN IF NOT EXISTS default_layout jsonb;

-- pf.dim_period: run setup_sql/gen_dim_period.sql to create and populate

CREATE TABLE IF NOT EXISTS pf.col_meta (
    id          serial PRIMARY KEY,
    source_id   integer NOT NULL REFERENCES pf.source(id) ON DELETE CASCADE,
    cname       text NOT NULL,
    label       text,
    role        text NOT NULL DEFAULT 'ignore',   -- dimension | value | units | date | ignore
    is_key      boolean NOT NULL DEFAULT false,   -- true = usable in WHERE slice
    dim_group   text,                             -- groups functionally dependent columns
    dim_period_col text,                          -- pf.dim_period column this dimension derives from
    in_grain    boolean NOT NULL DEFAULT false,   -- true = column defines the display grain
    opos        integer,
    UNIQUE (source_id, cname)
);

-- backfill columns for existing installs (must follow the CREATE above)
ALTER TABLE pf.col_meta ADD COLUMN IF NOT EXISTS dim_group text;
ALTER TABLE pf.col_meta ADD COLUMN IF NOT EXISTS dim_period_col text;
ALTER TABLE pf.col_meta ADD COLUMN IF NOT EXISTS in_grain boolean NOT NULL DEFAULT false;

CREATE TABLE IF NOT EXISTS pf.version (
    id              serial PRIMARY KEY,
    source_id       integer NOT NULL REFERENCES pf.source(id) ON DELETE RESTRICT,
    name            text NOT NULL,
    description     text,
    status          text NOT NULL DEFAULT 'open',               -- open | closed
    exclude_iters   jsonb NOT NULL DEFAULT '["reference"]'::jsonb,
    created_at      timestamptz NOT NULL DEFAULT now(),
    created_by      text,
    closed_at       timestamptz,
    closed_by       text,
    UNIQUE (source_id, name)
);

CREATE TABLE IF NOT EXISTS pf.log (
    id          bigserial PRIMARY KEY,
    version_id  integer NOT NULL REFERENCES pf.version(id) ON DELETE CASCADE,
    pf_user     text NOT NULL,
    stamp       timestamptz NOT NULL DEFAULT now(),
    operation   text NOT NULL,   -- baseline | reference | scale | recode | clone
    slice       jsonb,
    params      jsonb,
    note        text,
    tag         text            -- initiative label, e.g. 'reduce_spend'; groups
                                -- adjustments into a bridge from baseline to current
);

-- adding tags to an install that predates them
ALTER TABLE pf.log ADD COLUMN IF NOT EXISTS tag text;
CREATE INDEX IF NOT EXISTS log_tag_idx ON pf.log (tag) WHERE tag IS NOT NULL;

-- seed tags for loads that predate the column: a baseline/reference note is the
-- segment's name ('Open Orders', 'Prior Year'), which is exactly what tag holds.
-- Adjustment notes are free text, not labels, so they are left alone.
UPDATE pf.log
SET tag = note
WHERE TRUE
    AND tag IS NULL
    AND note IS NOT NULL
    AND note <> ''
    AND operation IN ('baseline', 'reference');

-- What a segment contributes to, independent of pf_iter.
--
-- pf_iter answers "can operations write to these rows"; bucket answers "does this
-- belong in the forecast number". Those are not the same question -- Open Orders is
-- loaded as reference so nothing adjusts it, yet it is part of the forecast -- so
-- neither can be derived from the other.
--
-- Free text with suggested values (Forecast / Prior Year / Prior Prior Year / Plan)
-- rather than an enum, so a new banner does not need a migration. Blank by default:
-- until a segment is labelled, the pivot falls back to showing its own name.
ALTER TABLE pf.log ADD COLUMN IF NOT EXISTS bucket text;
CREATE INDEX IF NOT EXISTS log_bucket_idx ON pf.log (bucket) WHERE bucket IS NOT NULL;

-- Master data for a dim_group: one row per key value, with its sibling columns.
--
-- The source is transactional and often a view over all history, so deriving a
-- member list from it is both slow and wrong -- slow because it means scanning
-- millions of rows, wrong because it can only describe what was transacted and
-- has no way to say a part is discontinued or that a new one exists before it
-- has sold. This table is the app's own list, refreshed from the source but
-- curatable independently of it.
CREATE TABLE IF NOT EXISTS pf.dim_member (
    source_id    integer NOT NULL REFERENCES pf.source(id) ON DELETE CASCADE,
    dim_group    text    NOT NULL,   -- matches pf.col_meta.dim_group
    key_value    text    NOT NULL,   -- the is_key column's value
    attrs        jsonb   NOT NULL DEFAULT '{}'::jsonb,  -- the sibling columns
    is_active    boolean NOT NULL DEFAULT true,
    source_seen  boolean NOT NULL DEFAULT true,  -- present in the source at last refresh
    added_at     timestamptz NOT NULL DEFAULT now(),
    updated_at   timestamptz NOT NULL DEFAULT now(),
    refreshed_at timestamptz,
    PRIMARY KEY (source_id, dim_group, key_value)
);

CREATE INDEX IF NOT EXISTS dim_member_active_idx
    ON pf.dim_member (source_id, dim_group) WHERE is_active;

-- generated operation SQL per source, stored after col_meta is configured
CREATE TABLE IF NOT EXISTS pf.sql (
    id           serial PRIMARY KEY,
    source_id    integer NOT NULL REFERENCES pf.source(id) ON DELETE CASCADE,
    operation    text NOT NULL,  -- get_data | baseline | reference | scale | recode | clone | undo
    sql          text NOT NULL,
    generated_at timestamptz NOT NULL DEFAULT now(),
    UNIQUE (source_id, operation)
);