Implement WeatherNews.fix_conflict(db, schedule)

- Compare a schedule against what's in the database.
- If schedule changes have been made,
  + record the cancellation
  + update the schedule to reflect the new reality

src/WeatherNews.jl

@@ -26,7 +26,11 @@ TITLES = Dict(
 
 function massage_fn(zone, leading_zero)
     td = Date(now(tz"Asia/Tokyo"))
-    zero_adjustment = if leading_zero 0 else 1 end
+    zero_adjustment = if leading_zero
+        0
+    else
+        1
+    end
     ymd = yearmonthday(td)
     zn = ZonedDateTime(now(), localzone())
     return function massage(item)
@@ -86,4 +90,34 @@ function update_schedule_with_live_video(db)
     )
 end
 
+"""
+TODO - Given a schedule, check the database for conflicting entries and fix them.
+
+This usually happens when a caster has to be rescheduled due to unforseen circumstances.
+"""
+function fix_conflict(db, schedule)
+    casters = DB.find_all_casters(db)
+    cid = eachrow(casters) |> rows -> map(x -> (x[:n] => x[:id]), rows) |> Dict
+    cname = eachrow(casters) |> rows -> map(x -> (x[:id] => x[:n]), rows) |> Dict
+    # iterate through schedule
+    for s in schedule
+        # find a db schedule row with the same jst
+        dbs = DB.find_schedule_by_jst(db, string(s[:t]))
+        if ismissing(dbs)
+            continue
+        end
+        # check if the caster matches
+        if cid[s[:caster]] != dbs[:caster_id]
+            # if the caster doesn't match,
+            #   add an entry to the cancellation table
+            #   update the schedule row with a new caster
+            #     the new caster may be NULL in rare cases
+            @info ("$(dbs[:id]) $(cname[dbs[:caster_id]]):$(dbs[:caster_id]) replaced by $(s[:caster]):$(cid[s[:caster]])")
+            DB.cancel_schedule(db, dbs[:id], cid[s[:caster]])
+        else
+            @debug "$(dbs[:id]) $(s[:caster]) matches"
+        end
+    end
+end
+
 end

src/db.jl

@@ -17,6 +17,14 @@ function find_or_create_caster(db, n)
     end
 end
 
+"""
+Find all casters
+"""
+function find_all_casters(db)
+    sql_select = "SELECT * FROM CASTER"
+    return DBInterface.execute(db, sql_select) |> DataFrame
+end
+
 """
 Find a segment by short name `n`.
 """
@@ -52,26 +60,16 @@ function insert_schedule(db, row)
     end
 end
 
-"""
-TODO - Given a schedule, check the database for conflicting entries and fix them.
-
-This usually happens when a caster has to be rescheduled due to unforseen circumstances.
-"""
-function fix_conflict(db, schedule)
-    # iterate through schedule
-    # find a db schedule row with the same jst
-    # check if the caster matches
-    # if the caster doesn't match,
-    #   add an entry to the cancellation table
-    #   update the schedule row with a new caster
-    #     the new caster may be NULL in rare cases
-end
-
 """
 Return a row from the schedule based on its `jst` time.
 """
 function find_schedule_by_jst(db, jst)
-    return DBInterface.execute(db, "SELECT * FROM schedule WHERE jst = ? LIMIT 1", [jst]) |> DataFrame
+    df = DBInterface.execute(db, "SELECT * FROM schedule WHERE jst = ? LIMIT 1", [jst]) |> DataFrame
+    if size(df, 1) == 0
+        return missing
+    else
+        return eachrow(df)[1]
+    end
 end
 
 """
@@ -87,3 +85,24 @@ function update_schedule_with_video(db, jst, video_id)
         return false
     end
 end
+
+"""
+Cancel a schedule, and replace the entry with a new caster (or none at all).
+"""
+function cancel_schedule(db, schedule_id, new_caster_id)
+    sql_insert = "INSERT INTO cancellation SELECT id, caster_id, segment_id, jst FROM schedule WHERE id = ?"
+    sql_update = "UPDATE schedule SET caster_id = ? WHERE id = ?"
+    try
+        DBInterface.transaction(
+            function()
+                DBInterface.execute(db, sql_insert, [schedule_id])
+                DBInterface.execute(db, sql_update, [new_caster_id, schedule_id])
+            end,
+            db
+        )
+    catch e
+        @debug e
+        return false
+    end
+    return true
+end