1 files changed, 149 insertions, 0 deletions
diff --git a/src/main/lsp/format.c b/src/main/lsp/format.c
new file mode 100644
index 0000000..2019a90
--- /dev/null
+++ b/src/main/lsp/format.c
@@ -0,0 +1,149 @@
+#include "format.h"
+
+#include "completion.h"
+#include "dged/buffer.h"
+#include "dged/buffer_view.h"
+#include "dged/minibuffer.h"
+#include "dged/settings.h"
+#include "dged/window.h"
+#include "main/completion.h"
+#include "main/lsp.h"
+
+struct formatted_buffer {
+  struct buffer *buffer;
+  bool save;
+};
+
+static uint32_t get_tab_width(struct buffer *buffer) {
+  struct setting *tw = lang_setting(&buffer->lang, "tab-width");
+  if (tw == NULL) {
+    tw = settings_get("editor.tab-width");
+  }
+
+  uint32_t tab_width = 4;
+  if (tw != NULL && tw->value.type == Setting_Number) {
+    tab_width = tw->value.data.number_value;
+  }
+  return tab_width;
+}
+
+static bool use_tabs(struct buffer *buffer) {
+  struct setting *ut = lang_setting(&buffer->lang, "use-tabs");
+  if (ut == NULL) {
+    ut = settings_get("editor.use-tabs");
+  }
+
+  bool use_tabs = false;
+  if (ut != NULL && ut->value.type == Setting_Bool) {
+    use_tabs = ut->value.data.bool_value;
+  }
+
+  return use_tabs;
+}
+
+static struct formatting_options options_from_lang(struct buffer *buffer) {
+  return (struct formatting_options){
+      .tab_size = get_tab_width(buffer),
+      .use_spaces = !use_tabs(buffer),
+  };
+}
+
+void handle_format_response(struct lsp_server *server,
+                            struct lsp_response *response, void *userdata) {
+
+  text_edit_vec edits = text_edits_from_json(&response->value.result);
+  struct formatted_buffer *buffer = (struct formatted_buffer *)userdata;
+
+  pause_completion();
+  if (!VEC_EMPTY(&edits)) {
+    apply_edits_buffer(server, buffer->buffer, edits, NULL);
+
+    if (buffer->save) {
+      buffer_to_file(buffer->buffer);
+    }
+  }
+  resume_completion();
+
+  text_edits_free(edits);
+  free(buffer);
+}
+
+static void format_buffer(struct lsp_server *server, struct buffer *buffer,
+                          bool save) {
+  struct formatted_buffer *b =
+      (struct formatted_buffer *)calloc(1, sizeof(struct formatted_buffer));
+  b->buffer = buffer;
+  b->save = save;
+
+  uint64_t id = new_pending_request(server, handle_format_response, b);
+  struct versioned_text_document_identifier doc =
+      versioned_identifier_from_buffer(buffer);
+
+  struct document_formatting_params params = {
+      .text_document.uri = doc.uri,
+      .options = options_from_lang(buffer),
+  };
+
+  struct s8 json_payload = document_formatting_params_to_json(&params);
+  lsp_send(lsp_backend(server),
+           lsp_create_request(id, s8("textDocument/formatting"), json_payload));
+
+  versioned_text_document_identifier_free(&doc);
+  s8delete(json_payload);
+}
+
+void format_document(struct lsp_server *server, struct buffer *buffer) {
+  format_buffer(server, buffer, false);
+}
+
+void format_document_save(struct lsp_server *server, struct buffer *buffer) {
+  format_buffer(server, buffer, true);
+}
+
+void format_region(struct lsp_server *server, struct buffer *buffer,
+                   struct region region) {
+  struct formatted_buffer *b =
+      (struct formatted_buffer *)calloc(1, sizeof(struct formatted_buffer));
+  b->buffer = buffer;
+  b->save = false;
+
+  uint64_t id = new_pending_request(server, handle_format_response, b);
+  struct versioned_text_document_identifier doc =
+      versioned_identifier_from_buffer(buffer);
+
+  struct document_range_formatting_params params = {
+      .text_document.uri = doc.uri,
+      .range = region_to_lsp(buffer, region, server),
+      .options = options_from_lang(buffer),
+  };
+
+  struct s8 json_payload = document_range_formatting_params_to_json(&params);
+  lsp_send(lsp_backend(server),
+           lsp_create_request(id, s8("textDocument/formatting"), json_payload));
+
+  versioned_text_document_identifier_free(&doc);
+  s8delete(json_payload);
+}
+
+int32_t format_cmd(struct command_ctx ctx, int argc, const char **argv) {
+  (void)ctx;
+  (void)argc;
+  (void)argv;
+
+  struct buffer_view *bv = window_buffer_view(windows_get_active());
+
+  struct lsp_server *server = lsp_server_for_lang_id(bv->buffer->lang.id);
+  if (server == NULL) {
+    return 0;
+  }
+
+  struct region reg = region_new(bv->dot, bv->mark);
+  if (bv->mark_set && region_has_size(reg)) {
+    buffer_view_clear_mark(bv);
+    format_region(server, bv->buffer, reg);
+  } else {
+    format_document(server, bv->buffer);
+  }
+
+  return 0;
+}