#include "ast.h"

#include <stdlib.h>
#include <stdio.h>

#include "util.h"

const char* SyntaxKindString(SyntaxKind syntaxKind)
{
    switch(syntaxKind)
    {
        case AccessExpression: return "AccessExpression";
        case AllocExpression: return "Alloc";
        case Assignment: return "Assignment";
        case BinaryExpression: return "BinaryExpression";
        case Comment: return "Comment";
        case CustomTypeNode: return "CustomTypeNode";
        case Declaration: return "Declaration";
        case Expression: return "Expression";
        case ForLoop: return "ForLoop";
        case DeclarationSequence: return "DeclarationSequence";
        case FunctionArgumentSequence: return "FunctionArgumentSequence";
        case FunctionCallExpression: return "FunctionCallExpression";
        case FunctionDeclaration: return "FunctionDeclaration";
        case FunctionModifiers: return "FunctionModifiers";
        case FunctionSignature: return "FunctionSignature";
        case FunctionSignatureArguments: return "FunctionSignatureArguments";
        case Identifier: return "Identifier";
        case IfStatement: return "If";
        case IfElseStatement: return "IfElse";
        case Number: return "Number";
        case PrimitiveTypeNode: return "PrimitiveTypeNode";
        case ReferenceTypeNode: return "ReferenceTypeNode";
        case Return: return "Return";
        case StatementSequence: return "StatementSequence";
        case StaticModifier: return "StaticModifier";
        case StringLiteral: return "StringLiteral";
        case StructDeclaration: return "StructDeclaration";
        case Type: return "Type";
        case UnaryExpression: return "UnaryExpression";
        default: return "Unknown";
    }
}

uint8_t IsPrimitiveType(
    Node *typeNode
) {
    return typeNode->children[0]->syntaxKind == PrimitiveTypeNode;
}

Node* MakePrimitiveTypeNode(
    PrimitiveType type
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = PrimitiveTypeNode;
    node->primitiveType = type;
    node->childCount = 0;
    return node;
}

Node* MakeCustomTypeNode(
    char *name
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = CustomTypeNode;
    node->value.string = strdup(name);
    node->childCount = 0;
    return node;
}

Node* MakeReferenceTypeNode(
    Node *typeNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = ReferenceTypeNode;
    node->childCount = 1;
    node->children = (Node**) malloc(sizeof(Node*));
    node->children[0] = typeNode;
    return node;
}

Node* MakeTypeNode(
    Node* typeNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = Type;
    node->childCount = 1;
    node->children = (Node**) malloc(sizeof(Node*));
    node->children[0] = typeNode;
    return node;
}

Node* MakeIdentifierNode(
    const char *id
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = Identifier;
    node->value.string = strdup(id);
    node->childCount = 0;
    return node;
}

Node* MakeNumberNode(
    const char *numberString
) {
    char *ptr;
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = Number;
    node->value.number = strtoul(numberString, &ptr, 10);
    node->childCount = 0;
    return node;
}

Node* MakeStringNode(
    const char *string
) {
    size_t slen = strlen(string);
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = StringLiteral;
    node->value.string = strndup(string + 1, slen - 2);
    node->childCount = 0;
    return node;
}

Node* MakeStaticNode()
{
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = StaticModifier;
    node->childCount = 0;
    return node;
}

Node* MakeFunctionModifiersNode(
    Node **pModifierNodes,
    uint32_t modifierCount
) {
    uint32_t i;
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = FunctionModifiers;
    node->childCount = modifierCount;
    if (modifierCount > 0)
    {
        node->children = malloc(sizeof(Node*) * node->childCount);
        for (i = 0; i < modifierCount; i += 1)
        {
            node->children[i] = pModifierNodes[i];
        }
    }

    return node;
}

Node* MakeUnaryNode(
    UnaryOperator operator,
    Node *child
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = UnaryExpression;
    node->operator.unaryOperator = operator;
    node->children = malloc(sizeof(Node*));
    node->children[0] = child;
    node->childCount = 1;
    return node;
}

Node* MakeBinaryNode(
    BinaryOperator operator,
    Node *left,
    Node *right
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = BinaryExpression;
    node->operator.binaryOperator = operator;
    node->children = malloc(sizeof(Node*) * 2);
    node->children[0] = left;
    node->children[1] = right;
    node->childCount = 2;
    return node;
}

Node* MakeDeclarationNode(
    Node* typeNode,
    Node* identifierNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = Declaration;
    node->children = (Node**) malloc(sizeof(Node*) * 2);
    node->childCount = 2;
    node->children[0] = typeNode;
    node->children[1] = identifierNode;
    return node;
}

Node* MakeAssignmentNode(
    Node *left,
    Node *right
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = Assignment;
    node->childCount = 2;
    node->children = malloc(sizeof(Node*) * 2);
    node->children[0] = left;
    node->children[1] = right;
    return node;
}

Node* StartStatementSequenceNode(
    Node *statementNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = StatementSequence;
    node->children = (Node**) malloc(sizeof(Node*));
    node->childCount = 1;
    node->children[0] = statementNode;
    return node;
}

Node* AddStatement(
    Node* statementSequenceNode,
    Node *statementNode
) {
    statementSequenceNode->children = realloc(statementSequenceNode->children, sizeof(Node*) * (statementSequenceNode->childCount + 1));
    statementSequenceNode->children[statementSequenceNode->childCount] = statementNode;
    statementSequenceNode->childCount += 1;
    return statementSequenceNode;
}

Node* MakeReturnStatementNode(
    Node *expressionNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = Return;
    node->children = (Node**) malloc(sizeof(Node*));
    node->childCount = 1;
    node->children[0] = expressionNode;
    return node;
}

Node* MakeReturnVoidStatementNode()
{
    Node *node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = ReturnVoid;
    node->childCount = 0;
    node->children = NULL;
    return node;
}

Node *StartFunctionSignatureArgumentsNode(
    Node *argumentNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = FunctionSignatureArguments;
    node->childCount = 1;
    node->children = (Node**) malloc(sizeof(Node*));
    node->children[0] = argumentNode;
    return node;
}

Node* AddFunctionSignatureArgumentNode(
    Node *argumentsNode,
    Node *argumentNode
) {
    argumentsNode->children = realloc(argumentsNode->children, sizeof(Node*) * (argumentsNode->childCount + 1));
    argumentsNode->children[argumentsNode->childCount] = argumentNode;
    argumentsNode->childCount += 1;
    return argumentsNode;
}

Node *MakeEmptyFunctionSignatureArgumentsNode()
{
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = FunctionSignatureArguments;
    node->childCount = 0;
    node->children = NULL;
    return node;
}

Node* MakeFunctionSignatureNode(
    Node *identifierNode,
    Node* typeNode,
    Node* arguments,
    Node* modifiersNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = FunctionSignature;
    node->childCount = 4;
    node->children = (Node**) malloc(sizeof(Node*) * (node->childCount));
    node->children[0] = identifierNode;
    node->children[1] = typeNode;
    node->children[2] = arguments;
    node->children[3] = modifiersNode;
    return node;
}

Node* MakeFunctionDeclarationNode(
    Node* functionSignatureNode,
    Node* functionBodyNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = FunctionDeclaration;
    node->childCount = 2;
    node->children = (Node**) malloc(sizeof(Node*) * 2);
    node->children[0] = functionSignatureNode;
    node->children[1] = functionBodyNode;
    return node;
}

Node* MakeStructDeclarationNode(
    Node *identifierNode,
    Node *declarationSequenceNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = StructDeclaration;
    node->childCount = 2;
    node->children = (Node**) malloc(sizeof(Node*) * 2);
    node->children[0] = identifierNode;
    node->children[1] = declarationSequenceNode;
    return node;
}

Node* StartDeclarationSequenceNode(
    Node *declarationNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = DeclarationSequence;
    node->children = (Node**) malloc(sizeof(Node*));
    node->childCount = 1;
    node->children[0] = declarationNode;
    return node;
}

Node* AddDeclarationNode(
    Node *declarationSequenceNode,
    Node *declarationNode
) {
    declarationSequenceNode->children = realloc(declarationSequenceNode->children, sizeof(Node*) * (declarationSequenceNode->childCount + 1));
    declarationSequenceNode->children[declarationSequenceNode->childCount] = declarationNode;
    declarationSequenceNode->childCount += 1;
    return declarationSequenceNode;
}

Node* StartFunctionArgumentSequenceNode(
    Node *argumentNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = FunctionArgumentSequence;
    node->childCount = 1;
    node->children = (Node**) malloc(sizeof(Node*));
    node->children[0] = argumentNode;
    return node;
}

Node* AddFunctionArgumentNode(
    Node *argumentSequenceNode,
    Node *argumentNode
) {
    argumentSequenceNode->children = realloc(argumentSequenceNode->children, sizeof(Node*) * (argumentSequenceNode->childCount + 1));
    argumentSequenceNode->children[argumentSequenceNode->childCount] = argumentNode;
    argumentSequenceNode->childCount += 1;
    return argumentSequenceNode;
}

Node *MakeEmptyFunctionArgumentSequenceNode()
{
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = FunctionArgumentSequence;
    node->childCount = 0;
    node->children = NULL;
    return node;
}

Node* MakeFunctionCallExpressionNode(
    Node *identifierNode,
    Node *argumentSequenceNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = FunctionCallExpression;
    node->children = (Node**) malloc(sizeof(Node*) * 2);
    node->childCount = 2;
    node->children[0] = identifierNode;
    node->children[1] = argumentSequenceNode;
    return node;
}

Node* MakeAccessExpressionNode(
    Node *accessee,
    Node *accessor
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = AccessExpression;
    node->children = (Node**) malloc(sizeof(Node*) * 2);
    node->childCount = 2;
    node->children[0] = accessee;
    node->children[1] = accessor;
    return node;
}

Node* MakeAllocNode(Node *typeNode)
{
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = AllocExpression;
    node->childCount = 1;
    node->children = (Node**) malloc(sizeof(Node*));
    node->children[0] = typeNode;
    return node;
}

Node* MakeIfNode(
    Node *expressionNode,
    Node *statementSequenceNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = IfStatement;
    node->childCount = 2;
    node->children = (Node**) malloc(sizeof(Node*));
    node->children[0] = expressionNode;
    node->children[1] = statementSequenceNode;
    return node;
}

Node* MakeIfElseNode(
    Node *ifNode,
    Node *statementSequenceNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = IfElseStatement;
    node->childCount = 2;
    node->children = (Node**) malloc(sizeof(Node*));
    node->children[0] = ifNode;
    node->children[1] = statementSequenceNode;
    return node;
}

Node* MakeForLoopNode(
    Node *identifierNode,
    Node *startNumberNode,
    Node *endNumberNode,
    Node *statementSequenceNode
) {
    Node* node = (Node*) malloc(sizeof(Node));
    node->syntaxKind = ForLoop;
    node->childCount = 4;
    node->children = (Node**) malloc(sizeof(Node*) * 4);
    node->children[0] = identifierNode;
    node->children[1] = startNumberNode;
    node->children[2] = endNumberNode;
    node->children[3] = statementSequenceNode;
    return node;
}

static const char* PrimitiveTypeToString(PrimitiveType type)
{
    switch (type)
    {
        case Int: return "Int";
        case UInt: return "UInt";
        case Bool: return "Bool";
        case Void: return "Void";
    }

    return "Unknown";
}

static void PrintBinaryOperator(BinaryOperator expression)
{
    switch (expression)
    {
        case Add:
            printf("+");
            break;

        case Subtract:
            printf("-");
            break;

        case Multiply:
            printf("*");
            break;
    }
}

static void PrintNode(Node *node, int tabCount)
{
    uint32_t i;
    for (i = 0; i < tabCount; i += 1)
    {
        printf("  ");
    }

    printf("%s: ", SyntaxKindString(node->syntaxKind));
    switch (node->syntaxKind)
    {
        case BinaryExpression:
            PrintBinaryOperator(node->operator.binaryOperator);
            break;

        case Declaration:
            break;

        case CustomTypeNode:
            printf("%s", node->value.string);
            break;

        case PrimitiveTypeNode:
            printf("%s", PrimitiveTypeToString(node->primitiveType));
            break;

        case Identifier:
            printf("%s", node->value.string);
            break;

        case Number:
            printf("%lu", node->value.number);
            break;
    }

    printf("\n");
}

void PrintTree(Node *node, uint32_t tabCount)
{
    uint32_t i;
    PrintNode(node, tabCount);
    for (i = 0; i < node->childCount; i += 1)
    {
        PrintTree(node->children[i], tabCount + 1);
    }
}

TypeTag* MakeTypeTag(Node *node) {
    if (node == NULL) {
        fprintf(stderr, "wraith: Attempted to call MakeTypeTag on null value.\n");
        return NULL;
    }

    TypeTag *tag = (TypeTag*)malloc(sizeof(TypeTag));
    switch (node->syntaxKind) {
        case Type:
            tag = MakeTypeTag(node->children[0]);
            break;

        case PrimitiveTypeNode:
            tag->type = Primitive;
            tag->value.primitiveType = node->primitiveType;
            break;

        case ReferenceTypeNode:
            tag->type = Reference;
            tag->value.referenceType = MakeTypeTag(node->children[0]);
            break;

        case CustomTypeNode:
            tag->type = Custom;
            tag->value.customType = strdup(node->value.string);
            break;

        case Declaration:
            tag = MakeTypeTag(node->children[0]);
            break;

        case StructDeclaration:
            tag->type = Custom;
            tag->value.customType = strdup(node->children[0]->value.string);
            break;

        case FunctionDeclaration:
            tag = MakeTypeTag(node->children[0]->children[1]);
            break;

        default:
            fprintf(stderr, 
                    "wraith: Attempted to call MakeTypeTag on"
                    " node with unsupported SyntaxKind: %s\n",
                    SyntaxKindString(node->syntaxKind));
            return NULL;
    }
    return tag;
}

char* TypeTagToString(TypeTag *tag) {
    if (tag == NULL) {
        fprintf(stderr, "wraith: Attempted to call TypeTagToString with null value\n");
        return NULL;
    }

    switch (tag->type) {
        case Unknown:
            return "Unknown";
        case Primitive:
            return PrimitiveTypeToString(tag->value.primitiveType);
        case Reference: {
            char *inner = TypeTagToString(tag->value.referenceType);
            size_t innerStrLen = strlen(inner);
            char *result = malloc(sizeof(char) * (innerStrLen + 5));
            sprintf(result, "Ref<%s>", inner);
            free(inner);
            return result;
        }
        case Custom:
            return tag->value.customType;
    }
}

void AddTypeTags(Node *ast) 
{
    fprintf(stderr, "wraith: AddTypeTags not implemented yet.\n");
}