map and chainage calculation

db/init.sql

@@ -222,3 +222,90 @@ CREATE TABLE IF NOT EXISTS project_folders (
     folder     TEXT NOT NULL,   -- directory part of rel_path ('' = project root)
     PRIMARY KEY (project_id, folder)
 );
+
+-- ---------------------------------------------------------------------------
+-- GPS pipeline (map view + chainage). A background sweep extracts each video's
+-- GPS track with exiftool (dashcam Doc{N} samples), one video at a time:
+--   gps_status: 'pending' → 'ok' (track stored) | 'none' (no GPS metadata)
+--                        | 'error' (exiftool/mount failure, see gps_error)
+-- The RAW track is immutable once scanned; a kept "Viterbi" correction goes to
+-- gps_track_corrected (map/chainage prefer it, raw is never modified).
+-- Track format: [[lat, lon, t_s], ...] (t_s = seconds from first sample).
+-- ---------------------------------------------------------------------------
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_status     TEXT NOT NULL DEFAULT 'pending';
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_track      JSONB;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_len_m      DOUBLE PRECISION;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_error      TEXT;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_scanned_at TIMESTAMPTZ;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_track_corrected JSONB;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_corrected_by    TEXT;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_corrected_at    TIMESTAMPTZ;
+-- Human-readable summary of what the correction did ("2 spikes · start stitched …").
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_corrected_note  TEXT;
+-- Data-quality + continuity metadata from the raw scan: absolute epoch of the
+-- first/last GPS fix (lets consecutive files stitch across a missing start),
+-- raw sample count and the largest inter-fix gap (dropout visibility).
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_start_epoch  DOUBLE PRECISION;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_end_epoch    DOUBLE PRECISION;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_sample_count INTEGER;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS gps_max_gap_s    DOUBLE PRECISION;
+-- Real media duration read from the container by the exiftool scan. Load-bearing for
+-- the stitch guard: an inter-file gap is only "missing start" when the track covers
+-- LESS than the file's duration — otherwise the camera simply wasn't recording.
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS duration_s DOUBLE PRECISION;
+CREATE INDEX IF NOT EXISTS idx_videos_gps ON videos(gps_status) WHERE gps_status = 'pending';
+
+-- ---------------------------------------------------------------------------
+-- Road types: admin-defined per-project labels (LHS/RHS/MCW/Servicelane, …)
+-- assigned to videos. Injected into the export/claim JSON as `road_type` and
+-- re-stamped on push (server-authoritative).
+-- ---------------------------------------------------------------------------
+CREATE TABLE IF NOT EXISTS project_road_types (
+    project_id INTEGER NOT NULL REFERENCES projects(id) ON DELETE CASCADE,
+    name       TEXT NOT NULL,
+    PRIMARY KEY (project_id, name)
+);
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS road_type TEXT NOT NULL DEFAULT '';
+
+-- ---------------------------------------------------------------------------
+-- Chainage (linear referencing with piecewise-linear calibration).
+-- chainage_points = admin-entered client calibration pairs (lat/lon ↔ chainage).
+-- Optional road_type tag scopes a point to one calibration group (LHS vs RHS are
+-- separate routes); '' = usable by any group.
+-- Per video:
+--   sr_chainage_*  = ACTUAL measured position along the GPS route (immutable,
+--                    regenerated only from GPS — never admin-editable)
+--   chainage_*     = client-calibrated values (error distributed between
+--                    consecutive control points)
+--   route_seq      = position of the video along the calibrated route
+-- ---------------------------------------------------------------------------
+CREATE TABLE IF NOT EXISTS chainage_points (
+    id         SERIAL PRIMARY KEY,
+    project_id INTEGER NOT NULL REFERENCES projects(id) ON DELETE CASCADE,
+    lat        DOUBLE PRECISION NOT NULL,
+    lon        DOUBLE PRECISION NOT NULL,
+    chainage_m DOUBLE PRECISION NOT NULL,
+    note       TEXT NOT NULL DEFAULT '',
+    road_type  TEXT NOT NULL DEFAULT '',
+    created_by TEXT NOT NULL DEFAULT '',
+    created_at TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+CREATE INDEX IF NOT EXISTS idx_chainage_points_project ON chainage_points(project_id);
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS chainage_start_m    DOUBLE PRECISION;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS chainage_end_m      DOUBLE PRECISION;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS sr_chainage_start_m DOUBLE PRECISION;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS sr_chainage_end_m   DOUBLE PRECISION;
+ALTER TABLE videos ADD COLUMN IF NOT EXISTS route_seq           INTEGER;
+
+-- The piecewise-linear calibration itself (per project + group), persisted at
+-- recompute time as sorted [s_m, chainage_m] anchors. Needed to evaluate chainage at
+-- ANY route position later — e.g. frame-exact per-annotation chainage in exports.
+CREATE TABLE IF NOT EXISTS chainage_calibrations (
+    project_id  INTEGER NOT NULL REFERENCES projects(id) ON DELETE CASCADE,
+    road_type   TEXT NOT NULL DEFAULT '',
+    anchors     JSONB NOT NULL,
+    route_len_m DOUBLE PRECISION NOT NULL DEFAULT 0,
+    computed_by TEXT NOT NULL DEFAULT '',
+    computed_at TIMESTAMPTZ NOT NULL DEFAULT now(),
+    PRIMARY KEY (project_id, road_type)
+);