DB_NAME=census
DB_USER=postgres
TIGER_SRID=4269
SHAPELY_URL=http://pypi.python.org/packages/source/S/Shapely/Shapely-1.0.14.tar.gz


# Dark magic. We set these makefile variables to be the result of the
# 'shell' function. The shell function, in turn, executes a Python
# script which determines the locations of these files.
SHP2PGSQL := $(shell bin/find_file_paths --root /usr --single shp2pgsql)
POSTGIS_SQL := $(shell bin/find_file_paths --root /usr lwpostgis.sql postgis.sql)
SPATIAL_REF_SYS_SQL := $(shell bin/find_file_paths --root /usr spatial_ref_sys.sql)

# Necessary to run test/data without prerequisites.
#
.PHONY : test data lib


# The default task, since it comes first in the list.
#
all: clean lib test


test:
	./bin/run_tests


# Download or check out any third-party libraries.
lib:
	if [ ! -d lib/Shapely ]; then  			\
		wget -O shapely.tar.gz $(SHAPELY_URL);  \
		tar -xvzf shapely.tar.gz -C lib/    ;   \
		rm shapely.tar.gz;                      \
		mv lib/Shapely* lib/Shapely;            \
	fi;


# Remove byte-compiled python code.
#
clean:
	find ./ -name '*.pyc' -print0 | xargs -0 rm -f


data:
	bin/download_data


# There is a small issue here with the blocks_db and lines_db
# targets. Each of these requires that the database exists, and might
# therefore depend on the newdb target. However, if /each/ of them
# depends on newdb, the database will be dropped twice and the data
# from one of {blocks, lines} would be lost.
#
# We therefore assume that the database already exists when blocks_db
# or lines_db are initiated.
blocks_db: data blocks_table
# All Blocks
#
# The table already exists, so we can append to it, and we don't have
# to create the GiST index.
	for state in data/census2000/*; do                  \
		$(SHP2PGSQL)		                    \
			-a                                  \
	                -s $(TIGER_SRID)		    \
		        -D				    \
	                $$state/blocks/*.shp                \
	          	tiger_blocks                        \
		  	| psql -U $(DB_USER) -d $(DB_NAME); \
	done;

# Summary File 1
#
# Run all of the geo (uf1) files through the import script. This has
# to happen after the blocks import since we impose a foreign key
# restriction.
	for state in data/census2000/*; do                  	    \
		bin/sf1blocks2sql $$state/sf1/*.uf1 sf1_blocks      \
                          | psql -U $(DB_USER) -d $(DB_NAME)        \
                          > /dev/null;				    \
	done;

# Run the query to combine the two blocks tables, and drop the
# constituents.
	psql -U $(DB_USER) \
	     -d $(DB_NAME) \
	     -f sql/combine-block-tables.sql


lines_db: data tiger_lines_table
# All Lines
#
# Since the table and index already exist, we can utilize -a,
# and leave -I out.
	for state in data/census2000/*; do                  	    \
		for shapefile in $$state/lines/*.shp; do       	    \
			echo "Importing $$shapefile.";		    \
			$(SHP2PGSQL)		                    \
				-a                                  \
			        -s $(TIGER_SRID)                    \
		          	$$shapefile                         \
		          	tiger_lines                         \
				| bin/filter-transactions           \
				| psql -U $(DB_USER) -d $(DB_NAME)  \
				> /dev/null;			    \
		done;						    \
	done;



# This imports the Tiger data using shp2pgsql. The shapefiles
# should exist, since this task depends on the "data" task, which
# downloads said shapefiles.
#
# After the TIGER import is done, we use the sf1blocks2sql script to
# parse and import the geographic header record information.
#
db: newdb blocks_data lines_data
	# Do nothing except fulfill our prerequisites.



# First, we drop and re-create the DB_NAME database (or schema,
# whatever). Then, we add PL/pgSQL support to the database.
#
# At that point, we import the two PostGIS files, postgis.sql and
# spatial_ref_sys.sql. The postgis.sql file contains the geometry
# functions, while spatial_ref_sys.sql contains a table of SRIDs, and
# their associated properties. PostGIS requires both.
#
newdb:
# Ignore the result of dropdb when it fails.
	dropdb -U $(DB_USER) $(DB_NAME) || true
	createdb -U $(DB_USER) $(DB_NAME)
	createlang -U $(DB_USER) plpgsql $(DB_NAME)

	psql -d $(DB_NAME)     \
             -U $(DB_USER)     \
             -f $(POSTGIS_SQL) \
             > /dev/null

	psql -d $(DB_NAME)             \
             -U $(DB_USER)             \
             -f $(SPATIAL_REF_SYS_SQL) \
	     > /dev/null


# This just runs the SQL script to create the sf1_blocks table.
sf1_blocks_table:
	psql -d $(DB_NAME)                      \
             -U $(DB_USER)                      \
             -f sql/create-sf1_blocks-table.sql \
	     > /dev/null


# Create the tiger_blocks table, and create its GiST index. Having the
# table already exist makes importing via shp2pgsql much easier.
# Any blocks file will work as an argument.
tiger_blocks_table:
	$(SHP2PGSQL)							  \
		-p                                                        \
		-I                                                        \
	        -s $(TIGER_SRID)                                          \
		data/census2000/maryland/blocks/tl_2009_24_tabblock00.shp \
		tiger_blocks						  \
		| psql -U $(DB_USER) -d $(DB_NAME)                        \
                > /dev/null

# Create the "blocks" table, which is the result of joining
# the tiger_blocks and sf1_blocks tables.
blocks_table: tiger_blocks_table sf1_blocks_table
	psql -U $(DB_USER) \
	     -d $(DB_NAME) \
	     -f sql/create-blocks-table.sql


# Prepare the tiger_lines table, and create the GiST index on its
# geometry column. Any lines shapefile will do here.
tiger_lines_table:
	$(SHP2PGSQL)						       \
		-p                                                     \
		-I                                                     \
	        -s $(TIGER_SRID)                    		       \
		data/census2000/maryland/lines/tl_2009_24510_edges.shp \
		tiger_lines					       \
		| psql -U $(DB_USER) -d $(DB_NAME)                     \
                > /dev/null

# Add a unique index on the "tlid" column.
	psql -U $(DB_USER) \
             -d $(DB_NAME) \
             -f sql/create_tlid_unique_index.sql