Remove hard coded bodystruct path everywhere

Aerc usually used the path []int{1} if it didn't know what the proper path is.
However this only works for multipart messages and breaks if it isn't one.

This patch removes all the hard coding and extracts the necessary helpers to lib.

commands/msg/forward.go

@@ -10,6 +10,7 @@ import (
 	"path"
 	"strings"
 
+	"git.sr.ht/~sircmpwn/aerc/lib"
 	"git.sr.ht/~sircmpwn/aerc/models"
 	"git.sr.ht/~sircmpwn/aerc/widgets"
 	"git.sr.ht/~sircmpwn/aerc/worker/types"
@@ -137,12 +138,10 @@ func (forward) Execute(aerc *widgets.Aerc, args []string) error {
 		}
 
 		// TODO: add attachments!
-		part := findPlaintext(msg.BodyStructure, nil)
+		part := lib.FindPlaintext(msg.BodyStructure, nil)
 		if part == nil {
-			part = findFirstNonMultipart(msg.BodyStructure, nil)
+			part = lib.FindFirstNonMultipart(msg.BodyStructure, nil)
-			if part == nil {
+			// if it's still nil here, we don't have a multipart msg, that's fine
-				part = []int{1}
-			}
 		}
 		store.FetchBodyPart(msg.Uid, part, func(reader io.Reader) {
 			buf := new(bytes.Buffer)

commands/msg/recall.go

@@ -8,6 +8,7 @@ import (
 	"github.com/emersion/go-message/mail"
 	"github.com/pkg/errors"
 
+	"git.sr.ht/~sircmpwn/aerc/lib"
 	"git.sr.ht/~sircmpwn/aerc/models"
 	"git.sr.ht/~sircmpwn/aerc/widgets"
 	"git.sr.ht/~sircmpwn/aerc/worker/types"
@@ -107,12 +108,11 @@ func (Recall) Execute(aerc *widgets.Aerc, args []string) error {
 		part *models.BodyStructure
 	)
 	if len(msgInfo.BodyStructure.Parts) != 0 {
-		path = findPlaintext(msgInfo.BodyStructure, path)
+		path = lib.FindPlaintext(msgInfo.BodyStructure, path)
 	}
 	part, err = msgInfo.BodyStructure.PartAtIndex(path)
 	if part == nil || err != nil {
 		part = msgInfo.BodyStructure
-		path = []int{1}
 	}
 
 	store.FetchBodyPart(msgInfo.Uid, path, func(reader io.Reader) {

commands/msg/reply.go

@@ -10,6 +10,7 @@ import (
 
 	"git.sr.ht/~sircmpwn/getopt"
 
+	"git.sr.ht/~sircmpwn/aerc/lib"
 	"git.sr.ht/~sircmpwn/aerc/models"
 	"git.sr.ht/~sircmpwn/aerc/widgets"
 )
@@ -169,14 +170,12 @@ func (reply) Execute(aerc *widgets.Aerc, args []string) error {
 			template = aerc.Config().Templates.QuotedReply
 		}
 
-		part := findPlaintext(msg.BodyStructure, nil)
+		part := lib.FindPlaintext(msg.BodyStructure, nil)
 		if part == nil {
 			// mkey... let's get the first thing that isn't a container
-			part = findFirstNonMultipart(msg.BodyStructure, nil)
+			// if that's still nil it's either not a multipart msg (ok) or
-			if part == nil {
+			// broken (containers only)
-				// give up, use whatever is first
+			part = lib.FindFirstNonMultipart(msg.BodyStructure, nil)
-				part = []int{1}
-			}
 		}
 		store.FetchBodyPart(msg.Uid, part, func(reader io.Reader) {
 			buf := new(bytes.Buffer)

commands/msg/utils.go

@@ -2,7 +2,6 @@ package msg
 
 import (
 	"errors"
-	"strings"
 
 	"git.sr.ht/~sircmpwn/aerc/commands"
 	"git.sr.ht/~sircmpwn/aerc/lib"
@@ -49,34 +48,3 @@ func (h *helper) messages() ([]*models.MessageInfo, error) {
 	}
 	return commands.MsgInfoFromUids(store, uid)
 }
-
-func findPlaintext(bs *models.BodyStructure, path []int) []int {
-	for i, part := range bs.Parts {
-		cur := append(path, i+1)
-		if strings.ToLower(part.MIMEType) == "text" &&
-			strings.ToLower(part.MIMESubType) == "plain" {
-			return cur
-		}
-		if strings.ToLower(part.MIMEType) == "multipart" {
-			if path := findPlaintext(part, cur); path != nil {
-				return path
-			}
-		}
-	}
-	return nil
-}
-
-func findFirstNonMultipart(bs *models.BodyStructure, path []int) []int {
-	for i, part := range bs.Parts {
-		cur := append(path, i+1)
-		mimetype := strings.ToLower(part.MIMEType)
-		if mimetype != "multipart" {
-			return path
-		} else if mimetype == "multipart" {
-			if path := findPlaintext(part, cur); path != nil {
-				return path
-			}
-		}
-	}
-	return nil
-}

lib/structure_helpers.go

@@ -0,0 +1,38 @@
+package lib
+
+import (
+	"strings"
+
+	"git.sr.ht/~sircmpwn/aerc/models"
+)
+
+func FindPlaintext(bs *models.BodyStructure, path []int) []int {
+	for i, part := range bs.Parts {
+		cur := append(path, i+1)
+		if strings.ToLower(part.MIMEType) == "text" &&
+			strings.ToLower(part.MIMESubType) == "plain" {
+			return cur
+		}
+		if strings.ToLower(part.MIMEType) == "multipart" {
+			if path := FindPlaintext(part, cur); path != nil {
+				return path
+			}
+		}
+	}
+	return nil
+}
+
+func FindFirstNonMultipart(bs *models.BodyStructure, path []int) []int {
+	for i, part := range bs.Parts {
+		cur := append(path, i+1)
+		mimetype := strings.ToLower(part.MIMEType)
+		if mimetype != "multipart" {
+			return path
+		} else if mimetype == "multipart" {
+			if path := FindFirstNonMultipart(part, cur); path != nil {
+				return path
+			}
+		}
+	}
+	return nil
+}

widgets/msgviewer.go

@@ -180,7 +180,7 @@ func createSwitcher(acct *AccountView, switcher *PartSwitcher,
 
 	if len(msg.BodyStructure().Parts) == 0 {
 		switcher.selected = 0
-		pv, err := NewPartViewer(acct, conf, msg, msg.BodyStructure(), []int{1})
+		pv, err := NewPartViewer(acct, conf, msg, msg.BodyStructure(), nil)
 		if err != nil {
 			return err
 		}

worker/lib/parse.go

@@ -21,8 +21,9 @@ var dateRe = regexp.MustCompile(`(((Mon|Tue|Wed|Thu|Fri|Sat|Sun))[,]?\s[0-9]{1,2
 	`([0-9]{4})\s([0-9]{2}):([0-9]{2})(:([0-9]{2}))?\s([\+|\-][0-9]{4})\s?`)
 
 func FetchEntityPartReader(e *message.Entity, index []int) (io.Reader, error) {
-	if len(index) < 1 {
+	if len(index) == 0 {
-		return nil, fmt.Errorf("no part to read")
+		// non multipart, simply return everything
+		return bufReader(e)
 	}
 	if mpr := e.MultipartReader(); mpr != nil {
 		idx := 0
@@ -41,10 +42,7 @@ func FetchEntityPartReader(e *message.Entity, index []int) (io.Reader, error) {
 			}
 		}
 	}
-	if index[0] != 1 {
+	return nil, fmt.Errorf("FetchEntityPartReader: unexpected code reached")
-		return nil, fmt.Errorf("cannont return non-first part of non-multipart")
-	}
-	return bufReader(e)
 }
 
 //TODO: the UI doesn't seem to like readers which aren't buffers

worker/maildir/search.go

@@ -10,6 +10,7 @@ import (
 
 	"git.sr.ht/~sircmpwn/getopt"
 
+	"git.sr.ht/~sircmpwn/aerc/lib"
 	"git.sr.ht/~sircmpwn/aerc/models"
 )
 
@@ -138,7 +139,12 @@ func (w *Worker) searchKey(key uint32, criteria *searchCriteria,
 	}
 	if parts&BODY > 0 {
 		// TODO: select which part to search, maybe look for text/plain
-		reader, err := message.NewBodyPartReader([]int{1})
+		mi, err := message.MessageInfo()
+		if err != nil {
+			return false, err
+		}
+		path := lib.FindFirstNonMultipart(mi.BodyStructure, nil)
+		reader, err := message.NewBodyPartReader(path)
 		if err != nil {
 			return false, err
 		}