build: add -ldl linker flag, recursive source discovery, and API test targets to Makefile

Makefile

@@ -5,7 +5,7 @@
 CC = gcc
 CFLAGS = -Wall -Wextra -Wpedantic -Wshadow -O2 -I./include
 CFLAGS += -fstack-protector-strong -D_FORTIFY_SOURCE=2
-LDFLAGS = -lX11 -lXext -lXinerama -lXrandr -lXft -lfontconfig -ldbus-1 -lcurl -lm -lpthread -lXtst -lXi
+LDFLAGS = -lX11 -lXext -lXinerama -lXrandr -lXft -lfontconfig -ldbus-1 -lcurl -lm -lpthread -lXtst -lXi -ldl
 
 # Directories
 SRC_DIR = src
@@ -13,9 +13,9 @@ INC_DIR = include
 BUILD_DIR = build
 BIN_DIR = bin
 
-# Find all source files automatically
-SRCS = $(wildcard $(SRC_DIR)/*.c)
-OBJS = $(SRCS:$(SRC_DIR)/%.c=$(BUILD_DIR)/%.o)
+# Find all source files automatically (including subdirectories)
+SRCS = $(shell find $(SRC_DIR) -name '*.c' -type f)
+OBJS = $(patsubst $(SRC_DIR)/%.c,$(BUILD_DIR)/%.o,$(SRCS))
 DEPS = $(OBJS:.o=.d)
 
 # Output binary
@@ -78,6 +78,11 @@ help:
 	@echo "  make deps     - Install dependencies (needs sudo)"
 	@echo "  make help     - Show this help"
 	@echo ""
+	@echo "API TESTING:"
+	@echo "  make test         - Run API integration tests"
+	@echo "  make test-quick   - Run quick tests (skip OCR)"
+	@echo "  make test-coverage- Run tests with coverage report"
+	@echo ""
 	@echo "AFTER INSTALL:"
 	@echo "  1. Log out of your current session"
 	@echo "  2. At login screen, select 'DWN' as your session"
@@ -108,6 +113,7 @@ $(TARGET): $(OBJS) | $(BIN_DIR)
 # Compile each source file
 $(BUILD_DIR)/%.o: $(SRC_DIR)/%.c | $(BUILD_DIR)
 	@echo "Compiling $<..."
+	@mkdir -p $(dir $@)
 	@$(CC) $(CFLAGS) -MMD -MP -c $< -o $@
 
 # Create build directory
@@ -271,6 +277,60 @@ deps:
 		exit 1; \
 	fi
 
+# =============================================================================
+# API INTEGRATION TESTS
+# =============================================================================
+
+TEST_PORT ?= 18777
+TEST_DISPLAY ?= :99
+
+.PHONY: test test-quick test-coverage test-isolated
+
+test:
+	@echo "Running API integration tests..."
+	@echo "Note: DWN must be running with API enabled (port 8777)"
+	@cd tests && python -m pytest -v
+
+test-quick:
+	@echo "Running quick API tests (skipping OCR)..."
+	@cd tests && python -m pytest -v -x --ignore=test_ocr_commands.py
+
+test-coverage:
+	@echo "Running API tests with coverage..."
+	@cd tests && python -m pytest --cov=. --cov-report=term-missing
+
+test-isolated: $(TARGET)
+	@echo "Starting isolated DWN test instance on port $(TEST_PORT)..."
+	@-kill $$(cat /tmp/dwn_test_dwn.pid 2>/dev/null) 2>/dev/null; true
+	@-kill $$(cat /tmp/dwn_test_xephyr.pid 2>/dev/null) 2>/dev/null; true
+	@rm -f /tmp/dwn_test_xephyr.pid /tmp/dwn_test_dwn.pid /tmp/dwn_test.log
+	@sleep 1
+	@Xephyr $(TEST_DISPLAY) -screen 1280x720 2>/dev/null & echo $$! > /tmp/dwn_test_xephyr.pid
+	@sleep 2
+	@DISPLAY=$(TEST_DISPLAY) $(TARGET) -p $(TEST_PORT) > /tmp/dwn_test.log 2>&1 & echo $$! > /tmp/dwn_test_dwn.pid
+	@sleep 3
+	@for i in 1 2 3 4 5; do \
+		if curl -s http://localhost:$(TEST_PORT)/api/status >/dev/null 2>&1; then \
+			echo "DWN API ready on port $(TEST_PORT)"; \
+			break; \
+		fi; \
+		echo "Waiting for DWN API... ($$i/5)"; \
+		sleep 1; \
+	done
+	@if ! curl -s http://localhost:$(TEST_PORT)/api/status >/dev/null 2>&1; then \
+		echo "ERROR: DWN API not responding. Check /tmp/dwn_test.log"; \
+		cat /tmp/dwn_test.log 2>/dev/null | tail -50; \
+		kill $$(cat /tmp/dwn_test_dwn.pid 2>/dev/null) 2>/dev/null || true; \
+		kill $$(cat /tmp/dwn_test_xephyr.pid 2>/dev/null) 2>/dev/null || true; \
+		exit 1; \
+	fi
+	@DWN_TEST_PORT=$(TEST_PORT) python -m pytest tests/ -v; \
+	EXIT_CODE=$$?; \
+	kill $$(cat /tmp/dwn_test_dwn.pid 2>/dev/null) 2>/dev/null || true; \
+	kill $$(cat /tmp/dwn_test_xephyr.pid 2>/dev/null) 2>/dev/null || true; \
+	rm -f /tmp/dwn_test_xephyr.pid /tmp/dwn_test_dwn.pid; \
+	exit $$EXIT_CODE
+
 # =============================================================================
 # CODE QUALITY (for developers)
 # =============================================================================