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.

8 files changed, 62 insertions, 54 deletions

diff --git a/commands/msg/forward.go b/commands/msg/forward.go
index 5f4da5cf..3ff0194f 100644
--- a/commands/msg/forward.go
+++ b/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)
-			if part == nil {
-				part = []int{1}
-			}
+			part = lib.FindFirstNonMultipart(msg.BodyStructure, nil)
+			// if it's still nil here, we don't have a multipart msg, that's fine
 		}
 		store.FetchBodyPart(msg.Uid, part, func(reader io.Reader) {
 			buf := new(bytes.Buffer)
diff --git a/commands/msg/recall.go b/commands/msg/recall.go
index 7c9ac193..5212041e 100644
--- a/commands/msg/recall.go
+++ b/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) {
diff --git a/commands/msg/reply.go b/commands/msg/reply.go
index 1deab316..6fd61413 100644
--- a/commands/msg/reply.go
+++ b/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 part == nil {
-				// give up, use whatever is first
-				part = []int{1}
-			}
+			// mkey... let's get the first thing that isn't a container
+			// if that's still nil it's either not a multipart msg (ok) or
+			// broken (containers only)
+			part = lib.FindFirstNonMultipart(msg.BodyStructure, nil)
 		}
 		store.FetchBodyPart(msg.Uid, part, func(reader io.Reader) {
 			buf := new(bytes.Buffer)
diff --git a/commands/msg/utils.go b/commands/msg/utils.go
index 5eb5fe53..cad0f82e 100644
--- a/commands/msg/utils.go
+++ b/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
-}
diff --git a/lib/structure_helpers.go b/lib/structure_helpers.go
new file mode 100644
index 00000000..21159a2b
--- /dev/null
+++ b/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
+}
diff --git a/widgets/msgviewer.go b/widgets/msgviewer.go
index f06b787f..a7b9fd61 100644
--- a/widgets/msgviewer.go
+++ b/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
 		}
diff --git a/worker/lib/parse.go b/worker/lib/parse.go
index ded7a83b..a14a6d33 100644
--- a/worker/lib/parse.go
+++ b/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 {
-		return nil, fmt.Errorf("no part to read")
+	if len(index) == 0 {
+		// 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("cannont return non-first part of non-multipart")
-	}
-	return bufReader(e)
+	return nil, fmt.Errorf("FetchEntityPartReader: unexpected code reached")
 }
 
 //TODO: the UI doesn't seem to like readers which aren't buffers
diff --git a/worker/maildir/search.go b/worker/maildir/search.go
index 005f6faa..ad3a45f3 100644
--- a/worker/maildir/search.go
+++ b/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
 		}