1 files changed, 142 insertions, 0 deletions
diff --git a/pkg/shell/state.go b/pkg/shell/state.go
new file mode 100644
index 0000000..ea62604
--- /dev/null
+++ b/pkg/shell/state.go
@@ -0,0 +1,142 @@
+package shell
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/jpappel/atlas/pkg/query"
+)
+
+type ValueType int
+
+const (
+	INVALID ValueType = iota
+	STRING
+	TOKENS
+	CLAUSE
+)
+
+type Value struct {
+	Type ValueType
+	Val  any
+}
+
+type State map[string]Value
+
+func (v Value) String() string {
+	switch v.Type {
+	case STRING:
+		s, ok := v.Val.(string)
+		if !ok {
+			return "Corrupted Type (expected string)"
+		}
+		return s
+	case TOKENS:
+		ts, ok := v.Val.([]query.Token)
+		if !ok {
+			return "Corrupted Type (expected []query.Token)"
+		}
+		return query.TokensStringify(ts)
+	case CLAUSE:
+		rootClause, ok := v.Val.(*query.Clause)
+		if !ok {
+			return "Corrupted Type (expected query.Clause)"
+		}
+		return rootClause.String()
+	case INVALID:
+		return "Invalid"
+	}
+	return fmt.Sprintf("Unknown @ %p", v.Val)
+}
+
+func (s State) String() string {
+	b := strings.Builder{}
+
+	for k, v := range s {
+		b.WriteString(k)
+		b.WriteByte(':')
+		switch v.Type {
+		case INVALID:
+			b.WriteString(" Invalid")
+		case STRING:
+			b.WriteString(" String")
+		case TOKENS:
+			b.WriteString(" Tokens")
+		case CLAUSE:
+			b.WriteString(" Clause")
+		default:
+			fmt.Fprintf(&b, " Unknown (%d)", v.Val)
+		}
+		b.WriteByte('\n')
+	}
+
+	return b.String()
+}
+
+func (s State) CmdTokenize(input string) (Value, bool) {
+	if len(input) == 0 {
+		return Value{}, false
+	}
+
+	var rawQuery string
+	if input[0] == '`' {
+		rawQuery = input[1:]
+	} else {
+		variable, ok := s[input]
+		if !ok {
+			fmt.Fprintln(os.Stderr, "Cannot tokenize: no variable with name", input)
+			return Value{}, false
+		} else if variable.Type != STRING {
+			fmt.Fprintln(os.Stderr, "Cannot tokenize: variable is not a string")
+			return Value{}, false
+		}
+
+		rawQuery, ok = variable.Val.(string)
+		if !ok {
+			fmt.Fprintln(os.Stderr, "Cannot tokenize: type corruption")
+			fmt.Fprintln(os.Stderr, "Type corruption, expected string")
+			panic("Type corruption")
+		}
+	}
+	tokens := query.Lex(rawQuery)
+	return Value{TOKENS, tokens}, true
+}
+
+func (s State) CmdParse(args string) (Value, error) {
+	if len(args) == 0 {
+		return Value{}, errors.New("no arguments for parse")
+	}
+
+	var tokens []query.Token
+	if tokenizeArgs, found := strings.CutPrefix(args, "tokenize "); found {
+		val, ok := s.CmdTokenize(tokenizeArgs)
+		if !ok {
+			return Value{}, errors.New("error occured during tokenization")
+		}
+		tokens = val.Val.([]query.Token)
+	} else {
+		variable, ok := s[args]
+		if !ok {
+			fmt.Fprintln(os.Stderr, "Cannot parse: no variable with name", args)
+			return Value{}, errors.New("variable does not exist")
+		} else if variable.Type != TOKENS {
+			fmt.Fprintln(os.Stderr, "Cannot parse: variable is not []query.Tokens")
+			return Value{}, errors.New("bad variable type")
+		}
+
+		tokens, ok = variable.Val.([]query.Token)
+		if !ok {
+			fmt.Fprintln(os.Stderr, "Cannot parse: type corruption")
+			fmt.Fprintln(os.Stderr, "Type corruption, expected []query.Tokens")
+			panic("Type corruption")
+		}
+	}
+
+	clause, err := query.Parse(tokens)
+	if err != nil {
+		return Value{}, err
+	}
+	return Value{CLAUSE, *clause}, err
+}