namespace pxt.patching {

export function computePatches(version: string, kind?: string): ts.pxtc.UpgradePolicy[] {

const patches = pxt.appTarget.compile ? pxt.appTarget.compile.patches : undefined;

if (!patches) return undefined;

const v = pxt.semver.tryParse(version || "0.0.0") || pxt.semver.tryParse("0.0.0");

let r: ts.pxtc.UpgradePolicy[] = [];

Object.keys(patches)

.filter(rng => pxt.semver.inRange(rng, v))

.forEach(rng => r = r.concat(patches[rng]));

if (kind)

r = r.filter(p => p.type == kind);

return r.length ? r : undefined;

}

export function upgradePackageReference(pkgTargetVersion: string, pkg: string, val: string): string {

if (val != "*") return pkg;

const upgrades = pxt.patching.computePatches(pkgTargetVersion, "package");

let newPackage = pkg;

if (upgrades) {

upgrades.forEach(rule => {

Object.keys(rule.map).forEach(match => {

if (newPackage == match) {

newPackage = rule.map[match];

}

});

});

}

return newPackage;

}

export function patchJavaScript(pkgTargetVersion: string, fileContents: string): string {

const upgrades = pxt.patching.computePatches(pkgTargetVersion);

let updatedContents = fileContents;

if (upgrades) {

upgrades.filter(u => u.type === "api").forEach(rule => {

Object.keys(rule.map).forEach(match => {

const regex = new RegExp(match, 'g');

updatedContents = updatedContents.replace(regex, rule.map[match]);

});

});

upgrades.filter(u => u.type === "userenum").forEach(rule => {

Object.keys(rule.map).forEach(enumName => {

const declRegex = new RegExp("enum\\s+" + enumName + "\\s*{", 'gm');

updatedContents = updatedContents.replace(declRegex, `enum ${rule.map[enumName]} {`);

const usageRegex = new RegExp(`(^|[^_a-zA-Z0-9])${enumName}(\\s*\\.)`, 'g');

updatedContents = updatedContents.replace(usageRegex, `$1${rule.map[enumName]}$2`);

});

});

}

return updatedContents;

}

}