Implement working proof of concept

src/wireviz/wv_cli.py

@@ -1,17 +1,26 @@
 import os
+from pathlib import Path
 import sys
 
 import click
 
-import wireviz.wireviz
+from wireviz import APP_NAME, __version__
+import wireviz.wireviz as wv
+from wireviz.wv_helper import open_file_read
+
 
 @click.command()
 @click.argument('filepath', nargs=-1)
+@click.option('-f', '--format', default='hpst')
 @click.option('-p', '--prepend', default=None)
-@click.option('-o', '--output', default='hpst')
+@click.option('-o', '--output-file', default=None)
 @click.option('-V', '--version', is_flag=True, default=False)
-def main(filepath, prepend, output, version):
-    print('WireViz!')
+def main(filepath, format, prepend, output_file, version):
+    print()
+    print(f'{APP_NAME} {__version__}')
+    if version:
+        return  # print version number only and exit
+
     # get list of files
     try:
         _ = iter(filepath)
@@ -20,8 +29,47 @@ def main(filepath, prepend, output, version):
     else:
         filepaths = list(filepath)
 
-    for f in filepaths:
-        print(f)
+    # determine output formats
+    format_codes = {'p': 'png', 's': 'svg', 't': 'tsv', 'c': 'csv', 'h': 'html', 'P': 'pdf'}
+    return_types = []
+    for code in format:
+        if code in format_codes:
+            return_types.append(format_codes[code])
+        else:
+            raise Exception(f'Unknown output format: {code}')
+    return_types = tuple(sorted(set(return_types)))
+    return_types_str = f'[{"|".join(return_types)}]' if len(return_types) > 1 else return_types[0]
+
+    # check prepend file
+    if prepend:
+        prepend = Path(prepend)
+        if not prepend.exists():
+            raise Exception(f'File does not exist:\n{prepend}')
+        print('Prepend file:', prepend)
+
+        with open_file_read(prepend) as file_handle:
+            prepend_input = file_handle.read() + '\n'
+    else:
+        prepend_input = ''
+
+    # run WireVIz on each input file
+    for file in filepaths:
+        file = Path(file)
+        if not file.exists():
+            raise Exception(f'File does not exist:\n{file}')
+
+        file_out = file.with_suffix('') if not output_file else output_file
+
+        print('Input file:  ', file)
+        print('Output file: ', f'{file_out}.{return_types_str}')
+
+        with open_file_read(file) as file_handle:
+            yaml_input = file_handle.read()
+
+        yaml_input = prepend_input + yaml_input
+
+        wv.parse(yaml_input, file_out=file_out)
+
     print()
 
 if __name__ == '__main__':