Implement 3-Layer GMPL → MUIO Conversion Pipeline (Parser, Interpreter, Transformer)

API/Classes/Case/GMPLParser.py

@@ -0,0 +1,333 @@
+"""
+Phase 1 — Pure GMPL syntax extraction.
+
+Parses a GMPL data file (.txt / .dat) into structured objects without
+semantic interpretation.  Every ``set`` and ``param`` declaration is
+captured, including multi-slice blocks, headerless tables, and empty
+param bodies.
+
+Public API
+----------
+    GMPLParser.parse_file(path)   → GMPLParseResult
+    GMPLParser.parse_string(text) → GMPLParseResult
+"""
+
+from __future__ import annotations
+
+import re
+from dataclasses import dataclass, field
+from pathlib import Path
+from typing import Optional, Union
+
+# ────────────────────────────────────────────────────────────
+# Data structures
+# ────────────────────────────────────────────────────────────
+
+@dataclass
+class RowEntry:
+    """One data row: a key string followed by numeric values."""
+    key: str
+    values: list[Union[int, float]]
+
+
+@dataclass
+class SliceBlock:
+    """
+    One slice of a ``param`` declaration.
+
+    *   ``header`` – the square-bracket header tokens, e.g. ``["RE1","*","*"]``.
+        ``None`` for headerless tables.
+    *   ``column_labels`` – the column names after ``:`` on the header line.
+    *   ``rows`` – the data rows.
+    """
+    header: Optional[list[str]] = None
+    column_labels: list[str] = field(default_factory=list)
+    rows: list[RowEntry] = field(default_factory=list)
+
+
+@dataclass
+class ParsedParam:
+    """A complete ``param`` declaration with its name, default, and slices."""
+    name: str
+    default: Optional[Union[int, float]] = None
+    slices: list[SliceBlock] = field(default_factory=list)
+
+
+@dataclass
+class GMPLParseResult:
+    """Bag holding every ``set`` and ``param`` extracted from a GMPL file."""
+    sets: dict[str, list[str]] = field(default_factory=dict)
+    params: list[ParsedParam] = field(default_factory=list)
+
+    # convenience
+    def param_names(self) -> list[str]:
+        return [p.name for p in self.params]
+
+    def summary(self) -> str:
+        lines = [f"Sets  : {len(self.sets)}"]
+        for sn, sv in self.sets.items():
+            lines.append(f"  {sn} ({len(sv)}) : {sv[:6]}{'...' if len(sv) > 6 else ''}")
+        lines.append(f"Params: {len(self.params)}")
+        for p in self.params:
+            total_rows = sum(len(s.rows) for s in p.slices)
+            lines.append(f"  {p.name} (default={p.default}, slices={len(p.slices)}, rows={total_rows})")
+        return "\n".join(lines)
+
+
+# ────────────────────────────────────────────────────────────
+# Tokeniser helpers
+# ────────────────────────────────────────────────────────────
+
+_COMMENT_RE = re.compile(r"#.*")
+
+def _strip_comments(text: str) -> str:
+    return _COMMENT_RE.sub("", text)
+
+def _tokenise(text: str) -> list[str]:
+    """Split GMPL text into semicolon-terminated statements."""
+    clean = _strip_comments(text)
+    parts = clean.split(";")
+    return [p.strip() for p in parts if p.strip()]
+
+def _try_number(s: str) -> Union[int, float, str]:
+    """Try to cast *s* to int or float; fall back to the original string."""
+    try:
+        v = float(s)
+        return int(v) if v == int(v) else v
+    except (ValueError, OverflowError):
+        return s
+
+
+# ────────────────────────────────────────────────────────────
+# Parser
+# ────────────────────────────────────────────────────────────
+
+class GMPLParser:
+    """
+    Pure-syntax GMPL parser.
+
+    Usage::
+
+        result = GMPLParser.parse_file("utopia.txt")
+        print(result.summary())
+    """
+
+    # ── public ──────────────────────────────────────────────
+    @staticmethod
+    def parse_file(path: str | Path) -> GMPLParseResult:
+        """Parse a ``.txt`` / ``.dat`` GMPL file and return structured result."""
+        text = Path(path).read_text(encoding="utf-8", errors="replace")
+        return GMPLParser.parse_string(text)
+
+    @staticmethod
+    def parse_string(text: str) -> GMPLParseResult:
+        """Parse raw GMPL text and return structured result."""
+        result = GMPLParseResult()
+        stmts = _tokenise(text)
+        for stmt in stmts:
+            first = stmt.split()[0].lower() if stmt.split() else ""
+            if first == "end":
+                break
+            if first == "set":
+                GMPLParser._parse_set(stmt, result)
+            elif first == "param":
+                GMPLParser._parse_param(stmt, result)
+        return result
+
+    # ── set ─────────────────────────────────────────────────
+    @staticmethod
+    def _parse_set(stmt: str, result: GMPLParseResult) -> None:
+        tokens = stmt.split()
+        name = tokens[1]
+        # find := position
+        body = ""
+        for i, t in enumerate(tokens):
+            if ":=" in t:
+                # Handle glued tokens like "YEAR:="
+                after = t.split(":=", 1)[1]
+                rest = tokens[i + 1 :]
+                body = (after + " " + " ".join(rest)).strip()
+                break
+        members = [m for m in body.split() if m]
+        result.sets[name] = members
+
+    # ── param ──────────────────────────────────────────────
+    @staticmethod
+    def _parse_param(stmt: str, result: GMPLParseResult) -> None:
+        tokens = stmt.split()
+        name = tokens[1]
+
+        # extract default
+        default_val: Optional[Union[int, float]] = None
+        for i, t in enumerate(tokens):
+            if t.lower() == "default":
+                dv = _try_number(tokens[i + 1])
+                if isinstance(dv, (int, float)):
+                    default_val = dv
+                break
+
+        # find := position
+        assign_pos = None
+        for i, t in enumerate(tokens):
+            if ":=" in t:
+                assign_pos = i
+                break
+
+        if assign_pos is None:
+            # declaration only, no data
+            result.params.append(ParsedParam(name=name, default=default_val))
+            return
+
+        # Rejoin everything after := (handle glued tokens)
+        glued_after = tokens[assign_pos].split(":=", 1)[1]
+        body_tokens = ([glued_after] if glued_after else []) + tokens[assign_pos + 1 :]
+        body = " ".join(body_tokens).strip()
+
+        if not body:
+            result.params.append(ParsedParam(name=name, default=default_val))
+            return
+
+        # Split into slices by `[` headers
+        slices = GMPLParser._split_slices(body)
+        parsed = ParsedParam(name=name, default=default_val)
+        for sl in slices:
+            parsed.slices.append(GMPLParser._parse_slice_block(sl))
+        result.params.append(parsed)
+
+    @staticmethod
+    def _split_slices(body: str) -> list[str]:
+        """Split param body into per-slice strings."""
+        # Find all '[' positions
+        bracket_positions = [m.start() for m in re.finditer(r"\[", body)]
+        if not bracket_positions:
+            return [body]
+
+        result = []
+        # Anything before first bracket is a headerless slice
+        prefix = body[: bracket_positions[0]].strip()
+        if prefix:
+            result.append(prefix)
+
+        for i, pos in enumerate(bracket_positions):
+            end = bracket_positions[i + 1] if i + 1 < len(bracket_positions) else len(body)
+            result.append(body[pos:end].strip())
+
+        return result
+
+    @staticmethod
+    def _parse_slice_block(text: str) -> SliceBlock:
+        """Parse one slice block into a SliceBlock object."""
+        block = SliceBlock()
+
+        # Extract header if present
+        if text.startswith("["):
+            bracket_end = text.index("]")
+            header_str = text[1:bracket_end]
+            block.header = [h.strip() for h in header_str.split(",")]
+            text = text[bracket_end + 1 :].strip()
+
+        # Look for colon separator (column labels)
+        if ":" in text:
+            parts = text.split(":")
+            # Column labels are between first and second ':'
+            if len(parts) >= 3:
+                # header : col1 col2 ... : \n row data
+                col_part = parts[1].strip()
+                block.column_labels = col_part.split()
+                # Rejoin remaining for rows
+                row_text = ":".join(parts[2:]).strip()
+                # Handle `:=` at start of row_text
+                if row_text.startswith("="):
+                    row_text = row_text[1:].strip()
+            elif len(parts) == 2:
+                # Might be `key : val` pairs or `:=` continuation
+                left = parts[0].strip()
+                right = parts[1].strip()
+                if right.startswith("="):
+                    # it's `:=` continuation
+                    row_text = right[1:].strip()
+                    # If left has column labels
+                    col_tokens = left.split()
+                    if col_tokens:
+                        block.column_labels = col_tokens
+                else:
+                    row_text = text
+            else:
+                row_text = text
+        else:
+            row_text = text
+
+        # Parse rows
+        if row_text:
+            GMPLParser._parse_rows(row_text, block)
+
+        return block
+
+    @staticmethod
+    def _parse_rows(text: str, block: SliceBlock) -> None:
+        """Parse row data into RowEntry objects."""
+        # Tokenize by whitespace
+        tokens = text.split()
+        if not tokens:
+            return
+
+        n_cols = len(block.column_labels) if block.column_labels else 0
+
+        if n_cols > 0:
+            # Table format: key val1 val2 ... valN
+            i = 0
+            while i < len(tokens):
+                key = tokens[i]
+                i += 1
+                vals = []
+                while len(vals) < n_cols and i < len(tokens):
+                    v = _try_number(tokens[i])
+                    if isinstance(v, (int, float)):
+                        vals.append(v)
+                        i += 1
+                    else:
+                        break
+                if vals:
+                    block.rows.append(RowEntry(key=key, values=vals))
+        else:
+            # Headerless: key value pairs or single values
+            i = 0
+            while i < len(tokens):
+                key = tokens[i]
+                i += 1
+                vals = []
+                while i < len(tokens):
+                    v = _try_number(tokens[i])
+                    if isinstance(v, (int, float)):
+                        vals.append(v)
+                        i += 1
+                    else:
+                        break
+                if vals:
+                    block.rows.append(RowEntry(key=key, values=vals))
+
+
+# ────────────────────────────────────────────────────────────
+# CLI entry point
+# ────────────────────────────────────────────────────────────
+
+if __name__ == "__main__":
+    import sys
+
+    if len(sys.argv) < 2:
+        print("Usage: python GMPLParser.py <data_file.txt>")
+        sys.exit(1)
+
+    result = GMPLParser.parse_file(sys.argv[1])
+    print(result.summary())
+    print("\n" + "=" * 60 + "\n")
+
+    for p in result.params[:10]:
+        print(f"\nparam {p.name} (default={p.default}):")
+        for si, s in enumerate(p.slices):
+            print(f"  slice[{si}]: header={s.header}")
+            print(f"    columns: {s.column_labels}")
+            for r in s.rows[:3]:
+                print(f"    {r}")
+            if len(s.rows) > 3:
+                print(f"    ... ({len(s.rows)} rows total)")